Endolymphatic sac papillary tumor (Heffner tumor)

Impact of an Endolymphatic Sac Tumor on Subjective and Objective Audiovestibular Function

OBJECTIVE

This study reports subjective and objective audiovestibular function in patients diagnosed with an endolymphatic sac tumor (ELST), to evaluate the clinical implication of vestibular testing in ELST patients.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary referral center/university hospital.

PATIENTS

Five patients diagnosed with unilateral ELST.

INTERVENTION

Subjective and objective audiovestibular tests; pure-tone average; speech discrimination score; the Video Head Impulse Test; the cervical vestibular evoked myogenic potential test; the caloric irrigation test; the Speech, Spatial and Qualities of Hearing Scale; the Tinnitus Handicap Inventory; and the Dizziness Handicap Inventory.

MAIN OUTCOME MEASURE

Findings and characteristics of both subjective and objective audiovestibular functions.

RESULTS

The mean pure-tone average and the mean speech discrimination score were 49 dB HL and 68% on the tumor ear and 13 dB HL and 99% contralaterally. The mean Speech, Spatial and Qualities of Hearing Scale score was 84, and the mean Tinnitus Handicap Inventory score was 64. Caloric testing showed a mean unilateral weakness of 80%. The Video Head Impulse Test of the lateral semicircular canal revealed refixation saccades on all tumor ears and an average gain value of 0.75 on the tumor ear versus 0.94 contralaterally. No cervical vestibular evoked myogenic potentials were elicited on the tumor side, whereas all but one was elicited contralaterally. The average Dizziness Handicap Inventory score was 47.

CONCLUSION

A characteristic pattern of abnormal caloric findings, refixation saccades, and normal vestibulo-ocular reflex gain alongside sensorineural hearing loss on the tumor ear was identified. Asymmetric sensorineural hearing loss in any patient should lead to objective vestibular evaluation to strengthen not only a targeted tumor surveillance strategy and the indication for imaging, but also the design of vestibular rehabilitation. In addition, vestibular findings may guide the choice of surgical approach.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumours: Tumours of the Ear

In the recently published 5th Edition of the World Health Organisation Classification of Head and Neck Tumours, there are relatively few changes to report in terms of nomenclature in lesions of ear and temporal bone and fewer developments in molecular pathogenesis in comparison to other sites, particularly in sinonasal tract. Ear and temporal bone tumours are rare and biopsy material is limited. As a result, resources in the literature are scarce with few large series, no controlled clinical trials and the approaches to staging and management are not standardised. New entities are difficult to characterise. The number of entries has, however, increased for tumours of the ear and temporal bone (thirteen) compared to the 4th Edition (eleven). Some lesions previously included in the 4th Edition considered to have no site-specific features have been excluded to be discussed elsewhere and other benign lesions that are specific to this site have been included. The tumours and tumour-like entities of ear and temporal bone are discussed here mindful that the chapter in the 5th edition better correlates disease processes with clinical information and imaging and as far as possible standardises nomenclature.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Familial Tumor Syndromes

The initiative of the 5th edition of the WHO classification of the Head and Neck Tumours establishing a new section dedicated to familial/heritable tumor syndromes with tumors and lesions in the head and neck region was much needed to better understand the tumours, diseases, and associated syndromes, as well as establish recommendations for monitoring and treating these patients. (WHO Classification of Tumours Editorial Board. Head and Neck tumours. Lyon (France): International Agency for Research on Cancer; 2022. https://publications.iarc.fr/ ). Within the newly established chapter on genetic tumor syndromes, we have described the main manifestations on the head and neck region in 15 syndromes. This review highlights the important findings within these syndromes, especially on the update on syndromes with tumors involving the head and neck region, as Gorlin syndrome/nevoid basal cell carcinoma syndrome associated with odontogenic keratocysts; Brooke-Spiegler syndrome/familial cylindromatosis and the associated membranous-type salivary gland basal cell adenoma, PTEN hamartoma tumor syndrome/Cowden syndrome with associated facial skin and mucosal lesions and characteristic multinodular thyroid lesions, Von Hippel Lindau syndrome and the associated middle ear endolymphatic sac tumor, as well as the fascinating genetic aspects of the diverse Head and Neck Paragangliomas. We will also discuss hyperparathyroidism-jaw tumor syndrome is characterized by parathyroid tumors in association with fibro-osseous jaw tumors, as well as head and neck desmoid tumors associated with familial adenomatous polyposis with Gardner syndrome variant familial, multicentric head and neck squamous cell carcinoma, tuberous sclerosis and neurofibromatosis type 1-associated head and neck lesions.

CAIX and pax-8 Commonly Immunoreactive in Endolymphatic Sac Tumors: A Clinicopathologic Study of 26 Cases with Differential Considerations for Metastatic Renal Cell Carcinoma in von Hippel-Lindau Patients

Endolymphatic sac tumors (ELSTs) are rare, slowly growing temporal bone neoplasms which show a high association with von Hippel-Lindau (VHL) syndrome. The immunohistochemistry evaluation of these papillary-cystic neoplasms frequently raises the differential diagnosis with renal cell carcinoma, among other metastatic neoplasms, whether in VHL patients or not. A cohort of 26 patients with ELSTs were evaluated for histologic features, immunohistochemistry findings, and association with VHL. Standard immunohistochemistry evaluation was performed. Sixteen females and 10 males ranging in age from 10 to 69 years (mean 44; VHL mean: 32) at initial presentation, comprised the cohort of patients. Most (86%) experienced hearing changes or inner ear symptoms (vertigo, dizziness), with an average duration of symptoms for 39 months (range 2-240 months). The tumors were an average of 2.9 cm (range 0.4-8 cm), with 14 left, 11 right sided and one bilateral tumor. Nine patients had documented VHL, with 3 patients having a concurrent or subsequent clear cell renal cell carcinoma. Patients were followed an average of 6.2 years (available in 24 patients): 19 alive without disease, 7.5 years; 2 dead without disease, 1.2 years; and 3 alive with disease, 3.1 years. The neoplastic cells show the following immunohistochemistry findings: AE1/AE3, EMA, CK7, CAIX, GLUT1, VEGF: 100% of cases tested were positive; pax-8: 85% of cases positive; CD10 and RCC: 0% of cases reactive. Based on this cohort of 26 patients with ELST, 9 of whom had VHL, the strong pax-8 and CAIX should be used in conjunction with negative CD10 and RCC to help exclude a metastatic renal cell carcinoma. As CAIX is an enzyme overexpressed in hypoxia and hypoxia inducible factor is what VHL protein regulates, this is an expected, although previously unreported finding. Whether part of VHL or not, VHL mutations may be a somatic rather than germline finding in the tumors, a possible further explanation for the CAIX reaction.

Extraneuraxial Hemangioblastoma: Clinicopathologic Features and Review of the Literature

Extraneuraxial hemangioblastoma occurs in nervous paraneuraxial structures, somatic tissues, and visceral organs, as part of von Hippel-Lindau disease (VHLD) or in sporadic cases. The VHL gene plausibly plays a key role in the initiation and tumorigenesis of both central nervous system and extraneuraxial hemangioblastoma, therefore, the underlying molecular and genetic mechanisms of the tumor growth are initially reviewed. The clinical criteria for the diagnosis of VHLD are summarized, with emphasis on the distinction of sporadic hemangioblastoma from the form fruste of VHLD (eg, hemangioblastoma-only VHLD). The world literature on the topic of extraneuraxial hemangioblastomas has been comprehensively reviewed with ∼200 cases reported to date: up to 140 paraneuraxial, mostly of proximal spinal nerve roots, and 65 peripheral, 15 of soft tissue, 6 peripheral nerve, 5 bone, and 39 of internal viscera, including 26 renal and 13 nonrenal. A handful of possible yet uncertain cases from older literature are not included in this review. The clinicopathologic features of extraneuraxial hemangioblastoma are selectively presented by anatomic site of origin, and the differential diagnosis is emphasized in these subsets. Reference is made also to 10 of the authors' personal cases of extraneuraxial hemangioblastomas, which include 4 paraneuraxial and 6 peripheral (2 soft tissue hemangioblastoma and 4 renal).

History of the Endolymphatic Sac: From Anatomy to Surgery

OBJECTIVES

To evaluate the historical descriptive origins of the anatomy of endolymphatic sac (ELS), its initial dilation description, its association with tumors, and lastly its surgical implication.

METHODS

A collection of historical and contemporary references, and selected textbooks were compiled spanning the 18th century to present day with specific focus on the description of the ELS, ELS dilation, and ELS tumors (ELSTs).

RESULTS

Domenico Cotugno describes the ELS in 1760. Carl Hasse introduces the term endolymphatic sac (saccus endolymphaticus) in 1873, which has remained in use till today. Carlo Mondini, in 1791, describes ELS dilation. Georges Portmann proposes opening the ELS for the treatment of Ménière's disease (MD) in 1926. In 1984, the first reported case of an ELST is described with pathology consisting of an adenoma. Four years later, in 1988, the first report is published suggesting ELSTs in direct association to von Hippel-Lindau disease.

CONCLUSION

Domenico Cotugno is precise in describing the ELS in 1760. A timeline of important events relating to the ELS is presented. These include ELS dilation, surgical opening of the ELS for Meniere's, and ELSTs relating to von Hippel-Lindau disease.

von Hippel-Lindau disease: surveillance strategy for endolymphatic sac tumors

PURPOSE

: Up to 16% of patients with the hereditary von Hippel-Lindau disease develop endolymphatic sac tumors of the inner ear. Early diagnosis and treatment of endolymphatic sac tumors can prevent audiovestibular morbidity, but optimal endolymphatic sac tumor surveillance strategy has yet to be determined. We aimed to evaluate endolymphatic sac tumor surveillance to determine the best surveillance strategy.

METHODS

: In a national prospective study, 40 VHL mutation carriers were interviewed about audiovestibular symptoms and had audiological examinations and magnetic resonance imaging of the inner ear. Further, we performed a meta-analysis including all reported endolymphatic sac tumor von Hippel-Lindau disease cases in the literature (N = 140 with 156 endolymphatic sac tumors).

RESULTS

: In the prospective study, endolymphatic sac tumors were suspected based on audiovestibular symptoms, audiometry, and magnetic resonance imaging in 34%, 30%, and 12.5% of subjects, respectively. In total, more than 90% of radiologically diagnosed endolymphatic sac tumors were associated with abnormal audiometric findings. No endolymphatic sac tumor genotype-phenotype correlations were found.

CONCLUSION

: We recommend annual audiometry as a first-line endolymphatic sac tumor screening tool, and in countries where periodic surveillance magnetic resonance imaging of the central nervous system is performed, specific images of the inner ear should be included. Audiometric abnormalities in patients with von Hippel-Lindau disease without magnetic resonance imaging-visible endolymphatic sac tumors could be due to microscopic endolymphatic sac tumors. Determination of audiometric endolymphatic sac tumor characteristics could further target screening and improve endolymphatic sac tumor diagnosis.