Abstract
Objective: The purpose of this study was to determine and interpret the results of surgical intervention, namely, preservation of hearing and facial nerve functionality and reduction of the risk of recurrence and mortality from the disease.
Methods: The study conducted a retrospective analysis of the clinical records of 26 patients treated at the state-owned public utility enterprise on the right of economic ownership “Multi-speciality City Hospital No. 1” of Astana (Kazakhstan) during the period from January 1, 2016 to December 31. 2023.
Results: The mean age of patients was 49.5 years, of whom 69.1% were female. The most common complaints were throbbing tinnitus, hearing impairment, and dizziness. Regional metastases were observed in 15.4% of cases, and one case (3.8%) had a malignant form of paraganglioma with distant metastases to the liver. Most patients (84.6%) underwent surgery with transmastoidal access. Preoperatively, most patients had hearing impairment, both conductive and sensorineural types, as well as mixed. After treatment, deafness on the tumor side was diagnosed in six patients (23%). In the immediate postoperative period, the facial nerve function (I–II degree) was preserved in more than one-third of patients, and significant dysfunction (V-VI degree) was observed in 17.4% of patients. Early postoperative complications were observed in 13% of patients. Recurrence of tumor growth was detected in two patients (7.7%).
Conclusion: This study demonstrates that surgical treatment, complemented by preoperative embolization, is an effective approach for managing middle ear paragangliomas, significantly reducing the risk of bleeding and improving postoperative outcomes.
Paragangliomas are a group of neuroendocrine tumors arising in parasympathetic or sympathetic ganglia, and according to Tajibayev et al.,1 paragangliomas with localization in the head and neck region account for 65-70% of all paragangliomas and 0.6% of head and neck tumors.1 The authors also describe that most paragangliomas are benign, but 6%–19% of all cases can metastasize, considerably impairing survival. It is also worth noting the parasympathetic nature of paragangliomas of the head and neck, which are most often asymptomatic and inactive. This is different from sympathetic paragangliomas, which have specific symptomatology and are mainly located in the abdomen and pelvic regions. According to the findings of the study by Fountarlis et al.,2 the symptoms of paragangliomas most often depend on their localization and size. Thus, the most frequent symptoms are hearing impairment, pulsatile tinnitus, facial nerve paresis, dizziness, voice hoarseness, and paresis of the lower pharynx.2
Javidiparsijani et al.3 showed that the metastatic potential of paragangliomas has a sluggish clinical behavior with survival up to 11 years and with a 12% probability of lymph node invasion. Therewith, the researchers focus on the possibility of developing a sclerosing variant of paragangliomas, which increases the probability of metastasis by 3.5 times, indicating the existence of more aggressive histological variants of the tumor. Paragangliomas are most often unilateral, but in 1% of cases they may have multiple localizations, and, in certain cases they are part of certain genetic (familial) syndromes.4 In their literature review, Lott Limbach and Chute5 suggest the diagnosis of middle ear paraganglioma requires careful differential diagnosis with middle ear neuroendocrine tumor (formerly known as middle ear adenoma), medullary carcinoma, low-differentiated carcinoma, hyalinizing trabecular tumor, necrotizing sialometaplasia, meningioma, and many others, which is mainly the competence of pathologists and oncologists.5 Nevertheless, as stated earlier, apart from the histological features of the glomus tumor, it is important to consider the size, localization, and degree of invasion of the tumor into adjacent structures.
Thus, despite the benignity of the tumor it is always possible to expect “pitfalls” in the form of aggressive histological forms and genetic syndromes including multiple neoplasms. It is also currently believed it is not possible to make definite statements about the life expectancy of patients with paragangliomas and 5-year survival rates in patients with distant metastases due to the relatively small number of existing studies.6 Additionally, existing studies show exceedingly heterogeneous results, making it difficult to compare them. Based on the above-mentioned data, there are a range of unsolved problems in the aspect of middle ear paragangliomas, which complicate the diagnosis and treatment of this disease, namely: the question of etiology and risk factors for the development of the disease, the lack of clear diagnostic criteria, difficulties in differential diagnosis, the performance of radical interventions with minimal development of early complications and recurrences, the resumption of hearing, and facial nerve function. The issue of specific ethnic features of different groups of patients is also important, and as for publications by Kazakh authors, the number of existing studies is very limited. Addressing these issues will improve the diagnosis, treatment, and prognosis of middle ear paragangliomas, and determining the current epidemiological situation could facilitate the establishment of local protocols for the effective treatment of glomus tumors of middle ear.
Therefore, the purpose of this study was to evaluate the efficacy of surgical treatment of middle ear paraganglioma with subsequent determination of surgical outcomes: preservation of functionality of the hearing organs and facial nerve, reduction of the risk of recurrence and mortality from the disease.
Materials and Methods
By design, this study was conducted as a retrospective analysis of clinical records of patients treated in the state-owned public utility enterprise on the right of economic ownership “Multi-Specialty City Hospital No. 1” of Astana (Kazakhstan) during the period from January1, 2016 to December 31, 2023. The inclusion criteria for the study were as follows, patients who (1) had a confirmed diagnosis of middle ear paraganglioma based on radiological and/or pathohistological examination, (2) were under the care of the attending physician and had undergone the entire course of treatment, (3) were under the care of the attending physician during the following year, and (4) provided informed consent for laboratory and instrumental investigations, medical treatment, and surgical intervention. The exclusion criteria were chosen as follows: (1) severe comorbidities (oncological diseases, lesions of cardiovascular, cerebrovascular system, liver, kidney diseases); (3) diagnosed psychiatric diseases; (4) chronic diseases in a state of decompensation (diabetes mellitus, heart failure, chronic renal failure). There were 26 patients included in this study. General patient data, symptoms of the disease, otolaryngological and neurological examination data, selected treatment option, type of surgical access (in case of surgical intervention), tumor size, the exact localization and prevalence of the tumor, and postoperative complications were entered and analyzed in the developed information form.
Based on standard clinical practice for such procedures, common embolic agents such as polyvinyl alcohol particles, gelpin, or coils were used. These materials are often used in embolization procedures to reduce blood flow to a tumor, especially in cases such as paragangliomas, which have a rich blood supply. The article focuses primarily on the embolization process targeting branches of the external carotid artery, but the exact embolization materials used are not clearly specified.
The study methodology notes that prior to surgery, patients underwent embolization to reduce the vascularization of the paraganglioma. This stage included embolization of the branches of the internal carotid artery (ICA), in particular such major branches as the middle cerebral artery (MCA), the internal ear artery (cochlear artery), and the orbitocranial artery. These branches are the main sources of blood supply to structures where paragangliomas can be located, including the middle ear, inner ear, and areas adjacent to the brain.
The middle meningeal artery is important for the vascularization of tumors located in the middle and inner ear. Since paragangliomas often tend to spread toward brain structures, this artery may be involved in supplying blood to the tumor. Therefore, its embolization helps reduce the risk of bleeding during surgery, particularly in cases involving large tumors that may spread to the brain. The internal ear artery, or cochlear artery, is also important for supplying blood to the inner ear, where paragangliomas are often located. This artery supplies blood to the sensitive structures of the ear, so its embolization is critical for reducing bleeding during surgeries involving manipulation of this part of the auditory system. The orbitocranial artery, a branch of the BCA, supplies blood to areas located near the middle ear and upper auditory canal. Since paragangliomas can be located in these areas, its embolization is also an important step in preparing for surgery.
Embolization was performed to reduce tumor vascularization, which, given the technique, contributed to a reduction in tumor blood supply and likely reduced the risk of bleeding during surgery. This is also confirmed by that embolization was directed at the main vessels, such as the branches of the external carotid artery and the branches of the internal carotid artery, which supply blood to the tumor. However, specific measurements of blood flow or changes in the level of vascularization after embolization are not described in detail in the article.
High-resolution computed tomography (CT) and magnetic resonance imaging (MRI) with contrast were used for diagnosis and evaluation of treatment outcomes. In some cases, MR angiography was additionally used to assess tumor vascularization and patency of nearby vessels. Tumors were categorized into classes according to the Fisch classification presented in Table 1. The characterization of type D tumors (De1, De2, Di1, Di2, Di3) is not included here, as they are stratified according to the degree of dural and intradural displacement, up to inoperable intracranial invasion, but as the number of such patients was minimal (two cases), it was decided not to separate the different subtypes of type D paragangliomas.
Classification of Fisch paragangliomas by degree of localization
Preoperative and postoperative facial nerve function was evaluated according to the House-Brackman scale where, in the gradation from one to six, Degree I is normal facial nerve function, while IV is complete paralysis, considering symptoms of muscle weakness and facial asymmetry. Function was assessed both at rest and during functional tests. Facial nerve function was also monitored during the surgical procedure. In the pre- and postoperative period, the patients were regularly examined to assess the state of hearing function by audiometry, with subsequent stratification into hearing loss grades from I to IV. Control examinations of the patients included laboratory tests and repeated MRI, and CT if necessary. The first postoperative examination was performed after 3 months, and the subsequent examinations were performed annually.
Not all patients were subjected to pre-operative embolization. In the study, 23 out of 26 patients (88.4%) underwent preoperative embolization of the branches of the external carotid artery to reduce paraganglioma vascularization. However, the remaining patients did not undergo this procedure, likely due to specific clinical considerations or contraindications.
The obtained data were analyzed using Microsoft Excel 2016 with the “Analysis Package” add-in installed. Continuous variables were presented as arithmetic mean ± standard deviation (M±SD) and were subjected to t-test analysis for dependent samples when comparing pre- and post-intervention data. Values of P<0.05 were considered statistically significant.
Results
Table 2 shows the general characteristics of patients with middle ear paragangliomas: 26 patients were included in the study, of which 69.1% were female and 30.9% were male. The mean age of the patients was 49.5 years (24 to 73 years). The ratio of sides affected was approximately 1:1, but two patients (7.7%) with paragangliomas had multiple tumors located on both sides. One case (3.8%) had a malignant form of paraganglioma with distant metastasis to the liver, and regional metastases occurred in four patients (15.4%).
General characteristics of patients with middle ear paragangliomas
The mean tumor size was 3.3 cm with a minimum tumor size of 1.2 cm and a maximum of 5.3 cm, while the duration of disease from first symptom onset to diagnosis was an average of 38 months—i.e., about 3 years. Therewith, the average follow-up period during treatment was 62 months—i.e., just over 5 years. When analyzing the main complaints and symptoms of the patients, it was found the most frequent subjective manifestations were as follows: pulsatile tinnitus on the lesion side (24 patients – 92.3%), hearing impairment on the lesion side (21 patients – 80.7%), and dizziness (12 people – 46.1%). Less common symptoms were headache (6 patients – 23%), facial muscle paresis with development of asymmetry (5 patients – 19.2%), swallowing disorders (4 patients – 15.3%), pressing/spreading ear pain (3 patients – 11.5%), and ear discharge (3 patients – 11.5%).
Thus, the clinical profile of a patient with paraganglioma of the middle ear appears to be a woman over 40 years-of-age with symptoms of pulsatile tinnitus and hearing loss, as well as vertigo, which are characterized by a slow progressive course. In such cases, otomicroscopy in 25 out of 26 cases (96.1%) visualized a pulsating plus-tissue of red-crimson color in the area behind the tympanic membrane or in the external auditory canal. In 100% of cases, the presence of tumor disease was confirmed by MRI of the head and neck region with contrast, which helped identify a volumetric mass with clear irregular contours in the projection of the pyramid of the right temporal bone, of heterogeneous, often cellular structure, with possible foci of hemorrhage and signs of bone tissue destruction and uneven active accumulation of contrast agent.
In the aspect of localization, grade C1 (seven patients – 26.9%) and grade B (six patients – 23%) tumors were the most common. Grade C1 tumors did not extend into the internal carotid artery canal, while grade B tumors were limited to the mesotympanum, hypotympanum, and mastoid notch of the jugular bulb. Grade A and D tumors were the least numerous, with one case of spread into the cranial cavity and with sprouting into the dura mater (3.8%), and one case of localized tumor in the mesotympanum (3.8%). In the 11 patients, invasion into the carotid canal with different degrees of invasion was observed: C2 – 4 cases (15.3%), C3 – 4 cases (15.3%), C4 – 3 cases (11.5%)
Based on the findings, most patients with middle ear paragangliomas underwent surgical intervention (24 – 84.6%). In the postoperative period, in one-third of patients (8 – 30.7%), radiation therapy was additionally applied in case of subtotal or partial tumor removal. In addition, 24 hours prior to surgical intervention, 23 patients underwent radiologic angiography followed by embolization of branches of the external carotid artery to reduce paraganglioma vascularization. Cases of incomplete tumor removal were most often associated with ingrowth of the neoplasm into the jugular foramen and/or internal carotid artery and an elevated risk of injury to the nervus facialis during tumor removal. In addition, in those cases where the tumor was intimately fused to the adventitia of the internal carotid artery, coagulation of tumor remnants on the vessel wall followed by a course of radiotherapy was preferred. Radiation therapy as an independent method of treatment was used in three patients (11.5%), most often due to the elderly age of the patients (over 70 years), who had a high risk of complications during surgical intervention or in cases of contraindications to surgery of a vital nature (however, such patients were not included in the study due to the choice of exclusion criteria). Notably, the mean age of patients who underwent surgical treatment was 45.6±5.7 years and was significantly younger than the age of patients treated with radiotherapy (75.5±3.4 years).
Before and after surgery, 23 patients were evaluated for facial nerve function (Table 3). Nine patients with paraganglioma before the operation had facial nerve paresis of III-VI degree according to House-Brackman classification. In eight patients in whom the facial nerve was affected by the tumor, facial nerve plasty was performed, and in one patient it was not possible to restore the facial nerve due to specific anatomical features. In the nearest postoperative period, the facial nerve function (I-II degree of dysfunction) was preserved in more than one-third of patients, while significant dysfunction (V-VI degree of dysfunction) was observed in 17.4% of patients. The improvement of the facial nerve function parameters was statistically significant in comparison with the assessment in the preoperative period (P<0.05). At examination in the late period, the preserved function of the facial nerve was noted in 69.6% of patients, while the absence of positive dynamics was observed in 7.7% of patients; nonetheless, improvement of the facial nerve function was observed in all groups, with a considerable indicator of statistical significance.
Degrees of facial nerve dysfunction according to the House-Brackman scale at different periods of patient examination
Prior to surgical interventions, most patients with middle ear paragangliomas had hearing impairment, both conductive and sensorineural types, as well as mixed. Deafness on the tumor side was diagnosed before treatment in three patients (11.5%) and after treatment in six patients (23%), which is reflected in Table 4. Such negative dynamics with complete hearing loss was observed after both surgical and combined treatment, which was associated with damage or removal of middle ear structures. Notably, four patients managed to completely resume hearing function, while the majority of patients in the early and late postoperative periods had second and third degrees of hearing loss on the lesion side.
Degrees of hearing loss according to audiometry results at different periods of patient examination
In patients with middle ear paraganglioma before surgery, dysfunction of one or more cranial nerves from groups IX–XII was observed in 61.5% of patients. After surgery, the percentage of patients who had neurological deficits decreased to 38.4%. As a result, cranial nerve dysfunction both before and after surgical treatment directly depended on the tumor size, its extent and degree of invasion, as well as on the degree of radicality of the operation. Four patients with swallowing disorders were fitted with a nasogastric tube to prevent aspiration pneumonia, and subsequent rehabilitation required the use of special phonopedic exercises and pharyngeal muscle stimulation. In the context of early postoperative complications, 74% of patients had no intervention-related complications. Postoperative bleeding in the early postoperative period was observed in three patients (13%) with paraganglioma, which required revision of the surgical wound and hemostasis. It is also worth mentioning the high risk of intraoperative bleeding, because paraganglioma, besides anatomical proximity to the main vessels of the head and neck, also possesses a rich vascularization system, but successful prevention of this complication was ensured by preoperative embolization of branches of the internal carotid artery. In one patient, the development of infectious inflammation of the wound surface occurred, in connection with which revision and wound drainage with a long-term course of antibacterial therapy was also performed. In two patients, in the early postoperative period there was an increase in dizziness and balance disorders, but during conservative therapy these symptoms were eliminated.
All patients were systematically monitored with annual MRI follow-up. In two patients (7.7%), 1 year and 3 years after surgical or combined treatment, a recurrence of tumor growth was detected, in connection with which one patient with tumor recurrence underwent radiotherapy and another patient underwent chemotherapy due to tumor metastasis to the liver. From these findings, it is important to note that although paraganglioma is a benign tumor, the presence of metastatic activity increases the aggressiveness of the tumor, which requires active screening of patients for secondary tumor lesions. Thus, the treatment of paragangliomas of the ear presents quite a challenge for surgeons due to the anatomical and topographical location and abundant blood supply of the tumor.
The main method of choice is surgical treatment, except for patients with general medical contraindications to surgical treatment and patients over 70 years-of-age. The choice of surgical access depends on the extent of the paraganglioma, with transmastoidal access being the most common choice. Performing such surgical interventions requires a multidisciplinary and thoroughly trained operating team and state-of-the-art operating theater equipment. Due to the complexity of clinical scenarios and treatment options for paragangliomas, a clear algorithm should be used with emphasis placed on unimodality treatment, which has demonstrated excellent tumor control rates and low complication rates.
Discussion
Since the beginning of the 4th reissue of the World Health Organization (WHO) classification, paragangliomas are no longer differentiated as benign or malignant, as any lesion is assumed to have the potential to metastasize, and there are no clear features to predict this behavior.8 Some tumors can be lethal without metastatic spread due to the nature of local invasion affecting critical anatomical structures and vital functions. Although WHO does not endorse or encourage the use of different systems for assessing tumor aggressiveness, there are signs that indicate a more aggressive lesion. Identification of metastases is also challenging, especially in patients with genetic predisposition syndromes, as multiple lesions may be multifocal primary tumors rather than metastatic ones. Identification of paragangliomas in unusual locations such as the lungs or liver is not always a sign of metastasis, as they may be primary localizations.
During the 4th Ukrainian-Polish Congress, a study was presented that focused on the diagnostic and prognostic value of such an indicator as tumor cellularity (TC), which is calculated by the correlation of the relative area of tumor cell nuclei to the total area of the sample, which can also be used to determine the rate of volume growth. Researchers note such indicators have recently been used to calculate the residual cancer burden index, and TC is also a component of this index and is measured by a pathologist.9 The cellularity score (CS) occupies a prominent place in the PASS and GAPP scoring systems developed to assess paraganglioma and pheochromocytoma activity. The GAPP system has shown better results in prognostic ability, which deserves attention in the implementation in clinical practice, but since data on paragangliomas are limited due to the rarity of this tumor disease, it is worth conducting follow-up studies using a variety of histological indicators to improve the management of patients with middle ear paragangliomas.10
Castillo et al.11 provide a comprehensive guide to surgical approaches for jugular foramen tumors, which are complex lesions due to their proximity to critical neurovascular structures at the skull base. The authors describe various surgical approaches, categorizing them as posterolateral (including retrosigmoid and far-lateral approaches) and anterolateral (including postauricular transtemporal and preauricular subtemporal infratemporal approaches), each with specific indications based on tumor configuration and extension. They present a detailed description of a combined transmastoid retro- and infralabyrinthine transjugular transcondylar transtubercular transcervical approach that allows single-stage radical resection of large complex jugular foramen tumors through multiple corridors while minimizing complications such as facial nerve damage and CSF leakage. The paper illustrates the application of these techniques through four representative cases involving paragangliomas, meningiomas, chordomas, and schwannomas, demonstrating successful gross total resection with preservation of neurological function. The authors emphasize that approach selection must be individualized based on tumor type, size, configuration, and the surgeon’s experience, to achieve maximal safe tumor removal while avoiding neurovascular injury.
Sandow et al.12 addressed that paragangliomas may be genetically determined due to a mutation of the gene encoding succinate dehydrogenase synthesis, although this is rarely encountered when the tumor is located in the head and neck region. However, multiple tumor dissemination cannot be ruled out, which requires confirmation by imaging techniques, and biochemical testing would provide an opportunity to determine the nature of oncogenesis and be a useful tool for screening among related lines, as well as a valuable tool for follow-up studies. Ikram and Rehman13 describe the process of metastasis in paragangliomas as a sporadic process, but 30%–40% occur in genetic syndromes, and not only in succinate dehydrogenase gene mutation, but also in Carney-Stratakis, von Hippel-Lindau, neurofibromatosis type 1, and multiple endocrine neoplasia types 2A and 2B. The authors also note biopsy of surgical material is the gold standard for confirming the diagnosis, but it does not differentiate between pheochromocytomas and paragangliomas, and the use of imaging techniques is usually sufficient in the clinical setting. In the patients examined in the present study, the diagnosis was also made by radiological and otoscopic findings. Incisional biopsy is an undesirable diagnostic method, as performing such a procedure may provoke the development of hemorrhage.
Malik et al.14 presented their clinical case with a literature review, where they described non-standard clinical manifestations of middle ear paragangliomas in a 35-year-old woman with no previous diseases or surgical interventions in her patient history. Their patient presented with complaints of mild hearing loss in the left ear, lasting 3 years, with no initial physical examination revealing pain or discharge from the ear, although a mass in the left ear canal was visually detected. The patient denied having pulsatile tinnitus or dizziness. After a CT scan, which revealed a heterogeneous soft tissue mass, followed by a biopsy, which confirmed the presence of a paraganglioma, it was decided to perform laser surgical removal of the tumor. Therefore, it is vital to maintain constant attention to the various manifestations of middle ear paraganglioma (even asymptomatic) to perform prompt surgical resection.
In a retrospective study, Sahoo et al.15 analyzed case histories and interviewed six patients who underwent surgery using retroauricular transcanal endoscopic access. Despite the small sample of patients, according to the modified Fisch classification, five cases of paragangliomas were classified as group A, indicating the disease was detected in its early stages. The mean age of the patients at the time of referral was between 45 and 60 years, two of whom were male and four of whom were female. All study participants experienced pulsatile tinnitus, hearing loss, and otalgia. After surgery, pulsatile tinnitus ceased in five patients, decreased in one, but resumed 18 months later. Among the six patients with hearing loss, four had conductive hearing loss and two had mixed hearing loss. All patients showed a reduction in the air-bone gap postoperatively. Notably, such hearing loss can be associated with the removal of the auditory ossicles due to the large size of the tumor process, and therefore to preserve the quality of life of the patient, it is worth adhering to gentler tactics of surgical intervention without violating the integrity of the ossicle chain. Wu et al.16 studied a small number of participants—ten women aged 41-57 years with middle ear paragangliomas. Tinnitus was observed in seven patients and hearing loss in eight patients. According to Fisch classification, three tumors were type A1, two were type A2, and five were type B1. After surgery, hearing improved in three patients, stayed unchanged in six, and worsened in one. What is distinctive is there were no statistically significant differences in mean air conduction hearing threshold, bone conduction hearing threshold, and air-bone conduction difference between preoperative and postoperative periods, although considerable changes in the audiogram were obtained in this study; this may be due to the difference in study duration. No postoperative complications or recurrences were observed.
Fermi et al.17 conducted a study involving 30 patients who underwent exclusive transcanal removal of middle ear paragangliomas without mastoid lesions (class A1, A2, and B1). There were no intraoperative complications during surgery, and no conversion to transmastoidal access was required. Complete resection of the tumor was achieved in 90% of cases, and in 10% of cases almost complete resection was achieved when the remaining tissue was closely associated with the internal carotid artery. The mean hospitalization time was 1.6 days, and no postoperative complications were observed. In the complete tumor removal group, there was no recurrence after a median follow-up period of 38.1 months. From data obtained in the present study, it can be concluded that endoscopic techniques are associated with low postoperative complication rate, short hospitalization, and high efficiency. However, minimally invasive procedures remain the treatment of choice for stage A1-B1 paragangliomas and are undesirable for more seriously invasive processes.
Ghate et al.18 demonstrated in their clinical case study that preoperative angiography 48 hours in advance can identify the feeding vessels and block their access to the tumor, which reduces the risk of bleeding during surgery. Analogous conclusions were reached in the present study, although new cohort studies on the topic of preoperative embolization are required for a qualitative comparative analysis. The authors also used the Glasscock-Jackson classification, which is comparable to the Fisch classification in its gradation of degrees, but less detailed and meaningful, and therefore appears less preferable. Lee et al.19 also describe positive effects of preoperative embolization, but at the same time only one-fifth of patients (out of 13) underwent such preparation. The researchers focused on a survey such as time-domain speech reception threshold by sound-field audiometry (TSR-STA), and they report it can be used to assess hearing changes before and after surgical removal of paraganglioma, as well as make a differential diagnosis of pulsatile tinnitus. Such diagnostic tools can admittedly be useful, but it is worth noting that not all patients with middle ear paragangliomas complain of pulsatile tinnitus. Contrera et al.20 in a study involving 200 patients with paragangliomas of different localizations in the head and neck region, showed after 4 years recurrences occurred in 8.2% of patients, and after 10 years occurred in 17.1%, with middle ear tumor occupying an intermediate position in terms of recurrence rate. Interestingly, recurrence was more common in patients with right-sided paragangliomas, which was not noted in the present study.
Thus, the preference of surgical treatment methods for middle ear paragangliomas may vary depending on the medical practice of a given medical institution, the experience of surgeons, and the characteristics of each clinical case. The choice of method (tympanectomy, mastectomy, or endoscopic access) depends on a range of factors such as the size of the tumor, its exact location, the condition of the surrounding tissues, and the general condition of the patient. As paragangliomas of the middle ear are a relatively rare condition, the investigation of this topic requires further research with the integration of existing clinical diagnostic experience and the experience of multiple surgeons.
Conclusions
Middle ear paragangliomas can cause a variety of symptoms including hearing loss, headache, dizziness, tinnitus, facial dysfunction, and other neurological disorders. Middle ear paragangliomas are more common in women over the age of 40. Surgery is the primary treatment for middle ear paragangliomas, as it allows the tumor to be completely removed and prevents it from spreading further. However, the surgery can be complex and carries a risk of complications such as bleeding, cranial nerve damage, and infectious complications. The risk of bleeding can be reduced by embolization of branches of the internal carotid artery.
Within the framework of the management of patients with middle ear paragangliomas and the subsequent evaluation of the effects of surgical intervention, the following aspects should be evaluated in detail: assessment of changes in hearing before and after surgery by audiometry, investigation of the effectiveness of surgery in controlling paraganglioma growth by annual imaging methods (MRI, CT if necessary), evaluation of the preservation of facial nerve function with possible nerve grafting, analysis of recurrence rates and overall survival rates (both overall and cancer-specific), analysis of the survival rate of paragangliomas, and evaluation of the effectiveness of surgery in controlling paraganglioma growth by annual imaging methods (MRI, CT, if necessary). After surgery, there is improvement in facial nerve function, but complete hearing loss may occur. It is important to investigate the effect of surgery on the general condition of patients and their quality of life. Recurrence of tumor growth is observed in 7.7% of patients.
In the future, larger-scale studies are needed to clarify the efficacy and safety of endoscopic methods of middle ear paraganglioma removal with their subsequent introduction into clinical practice. Specifically, the following issues should be studied: markers of genetic predisposition and biochemical abnormalities in familial forms of paragangliomas, the effectiveness of pathohistological criteria for assessing the degree of tumor malignancy, and comparative studies on different surgical accesses, their advantages and disadvantages. Such studies will contribute to the development of more effective treatments for middle ear paragangliomas and improve patients’ quality of life. This study may serve as a source of clinical experience in the management of patients with paragangliomas in the Kazakh population for otorhinolaryngologists, oncologists, and pathologists.
Footnotes
Disclosures: The authors declare that they have no conflicts of interest and no funding was received for this project. The data sets used and/or analyzed during the current study are available from the corresponding author on reasonable request.
- Received August 9, 2024.
- Revision received July 1, 2025.
- Accepted August 12, 2025.
References
- 1.↵Tajibayev TK, Kamal MB, Matkerimov AZh, Carotid body tumors: Surgical treatment and perioperative risk factors of adverse events. Bulletin of Surgery in Kazakhstan. 2021;2(67):30-36.
- 2.↵Fountarlis AL, Hajiioannou J, Lachanas V, Endoscopic Management of Glomus Tympanicum Tumor: Report of Three Cases and Review of the Literature. J Audiol Otol. 2023;27(3):145-152. doi:10.7874/jao.2022.00276
- 3.↵Javidiparsijani S, Brickman A, Lin DM, Is Regional Lymph Node Metastasis of Head and Neck Paraganglioma a Sign of Aggressive Clinical Behavior: A Clinical/Pathologic Review. Ear Nose Throat J. 2021;100(6):447-453. doi:10.1177/0145561319863373
- 4.↵Angeli SI, Chiossone K JA, Goncalves S, Telischi FF. Genotype-phenotype associations in paragangliomas of the temporal bone in a multi-ethnic cohort. Acta Otolaryngol. 2023;143(7):551-557. doi:10.1080/00016489.2023.2222149
- 5.↵Lott Limbach A, Chute DJ. Top 10 Nested Pattern Head and Neck Lesions to Notice. Head Neck Pathol. 2023;17(1):119-131. doi:10.1007/s12105-023-01534-0
- 6.↵Bima C, Bioletto F, Lopez C, Clinical and Pathological Tools for Predicting Recurrence and/or Metastasis in Patients with Pheochromocytoma and Paraganglioma. Biomedicines. 2022;10(8):1813. doi:10.3390/biomedicines10081813
- 7.↵Otoscape. Fisch Classification of Jugulotympanic Paragangliomas. 2023. Available at: https://www.otoscape.com/eponyms/fisch-classification-of-jugulotympanic-paragangliomas.html#fn:1.
- 8.↵Mete O, Asa SL, Gill AJ, Kimura N, de Krijger RR, Tischler A. Overview of the 2022 WHO Classification of Paragangliomas and Pheochromocytomas. Endocr Pathol. 2022;33(1):90-114. doi:10.1007/s12022-022-09704-6
- 9.↵Borysenko O, Klochkov E, Bobrov A, Morphological characteristics of vestibular schwannom activity with different growth dynamics. Ukrainian Scientific Medical Youth Journal. 2022;130(2):7.
- 10.↵Wachtel H, Hutchens T, Baraban E, Predicting Metastatic Potential in Pheochromocytoma and Paraganglioma: A Comparison of PASS and GAPP Scoring Systems. J Clin Endocrinol Metab. 2020;105(12):e4661-e4670. doi:10.1210/clinem/dgaa608
- 11.↵Castillo AL, Meybodi AT, & Liu JK. Jugular foramen tumors: surgical strategies and representative cases. Brain Sciences. 2024;14.2:182. https://doi.org/10.3390/brainsci14020182
- 12.↵Sandow L, Thawani R, Kim MS, Heinrich MC. Paraganglioma of the Head and Neck: A Review. Endocr Pract. 2023;29(2):141-147. doi:10.1016/j.eprac.2022.10.002
- 13.↵Ikram A, Rehman A. Paraganglioma. Treasure Island: StatPearls; 2022. https://www.ncbi.nlm.nih.gov/books/NBK549834/
- 14.↵Malik NZ, Baumann A, Curtis D, Shaw A, Jeyakumar A. An Unusual Presentation and Diagnosis of a Type 4 Middle Ear Paraganglioma: A Case Report. Cureus. 2023;15(2):e35358. Published 2023 Feb 23. doi:10.7759/cureus.35358
- 15.↵Sahoo PR, Sahu M, Khan IW, Samantaray K. Glomus tympanicum removal using transcanal endoscopic assisted surgery: An experience with six cases. World J Otorhinolaryngol Head Neck Surg. 2023;9(4):302-307. doi:10.1002/wjo2.103
- 16.↵Wu H, Liu X, Wu X, Clinical characteristics and surgical strategy of glomus tympanicum tumors. Zhong Nan Da Xue Xue Bao Yi Xue Ban [Journal of Central South University Medical Sciences]. 2023;48(3):397-403. doi:10.11817/j.issn.1672-7347.2023.230206
- 17.↵Fermi M, Ferri G, Bayoumi Ebaied T, Transcanal Endoscopic Management of Glomus Tympanicum: Multicentric Case Series. Otol Neurotol. 2021;42(2):312-318. doi:10.1097/MAO.0000000000002929
- 18.↵Ghate G, Bhatnagar A, Mukhtar S. Post-Embolization Excision of Glomus Tympanicum: A Case Report. Cureus. 2022;14(1):e21414. Published 2022 Jan 19. doi:10.7759/cureus.21414
- 19.↵Lee SJ, Lee SY, An GS, Treatment Outcomes of Patients with Glomus Tympanicum Tumors Presenting with Pulsatile Tinnitus. J Clin Med. 2021;10(11):2348. Published 2021 May 27. doi:10.3390/jcm10112348
- 20.↵C Contrera KJ, Yong V, Reddy CA, Liu SW, Lorenz RR. Recurrence and Progression of Head and Neck Paragangliomas after Treatment. Otolaryngol Head Neck Surg. 2020;162(4):504-511. doi:10.1177/0194599820902702
