Neuroendocrine neoplasms of the middle ear: Unpredictable tumor behavior and tendency for recurrence

Abstract

Background Middle ear adenomatous neuroendocrine tumors (MEANTs) are rare temporal bone tumors. This study evaluates its clinical behavior and therapy outcome. Method Retrospective case review in a tertiary referral center evaluating histopathology, immunohistochemistry, treatment, and outcome. Results Nine patients were diagnosed with MEANT. One patient presented with locally invasive tumor and underwent extensive en‐bloc tumor resection with adjuvant radiotherapy. Seven of eight patients with locally non‐aggressive tumor confined to the tympanomastoid space underwent tumor resection. Two patients were disease‐free, five presented recurrence, even after apparent successful surgery. All tumors showed neuroendocrine features. Histopathology and immunohistochemistry did not yield prognostic tumor characteristics. Conclusion MEANTs are rare tumors with uncertain biological behavior and subsequent unpredictable clinical course. The preferred treatment is complete surgical tumor resection. They have a high tendency for recurrence, irrespective of negative intermediary surgery. As of yet, there are no prognostic biomarkers, including histopathology and immunohistochemistry.

Late Recurrence of a Rare Middle Ear Neuroendocrine Tumor With an Intracranial Extension to the Temporal Fossa: A Case Report

“…Other clinical manifestations such as blockage, aural fullness, otalgia, tinnitus, or vertigo may occur, depending greatly on the size, location, and infiltration of the tumor. Facial nerve paresis has also been reported, which could be more related to anatomical abnormalities or local compression rather than an invasion of the tumor [7][8][9]. Differential diagnosis of middle ear masses with progressive hearing loss includes middle ear otitis, cholesteatoma, acoustic neuroma (schwannoma), meningioma with glandular structure, encephalocele, rhabdomyosarcoma, jugulotympanic paraganglioma, endolymphatic papillary tumor, and adenocarcinoma.…”

“…These findings were consistent with neuroendocrine tumors in the existing literature and differentiated MeNET from other tumors, such as paraganglioma, the most common tumor in the middle ear, but immunohistochemically should be negative for keratins and have sustentacular cells positive for S100. The most recent reviews do not suggest any reliable, based on consensus, histopathological or immunohistochemical markers that predict tumor behavior and overall clinical outcome; therefore, a long-term follow-up is recommended [9]. Current MeNET classification is incomplete; however, historically, two large studies have suggested ways to classify MeNETs: one according to immunohistochemical markers and the presence of metastasis and another based on TNMS.…”

“…In our case, the patient had recurrent otitis media, the first preoperative temporal bone CT suggested chronic otitis media, and further surgical intervention was required to clear this suspicion. In some cases, single-photon emission computerized tomography (SPECT) or positron emission tomography (PET) scans can be used as a diagnostic tool for metastasized disease [ 9 ]. The imaging features are non-specific and still relatively ill-defined since they are based on scarce case reports.…”

“…The mean follow-up time published before 2018 was approximately 55 months. The most recent and larger study of nine patients by van der Lans et al, with a median of 155 months follow-up time, proposed that an even higher percentage (71%) of patients had recurrent MeNET after being treated for local and non-aggressive tumor [ 9 ]. However, in this article, recurrence and invasion into the dura mater of the middle cranial fossa were not mentioned.…”

Middle Ear Cavity and Mastoid Neuroendocrine Tumor Presenting as Otomastoiditis with Cholesteatoma: A Clinicoradiological and Histopathological Correlation

“…This study reported an unpredictable tumor behavior, a high tendency for recurrence, and lack of predictive histopathological/immunohistochemical markers in MEANTs. 19 …”