Late metastasis of breast adenocarcinoma into internal auditory canal and cerebellopontine angle: case report

Abstract

-A case of metastasis of breast adenocarcinoma into the internal auditory canal (IAC) and cerebellopontine angle (CPA) is presented, which appeared 16 years after primary tumor had been treated by surgery and radiation therapy. The 66-year old patient was considered cured from the primary disease, when she started with a rapidly developing hearing loss and intermittent facial palsy. Magnetic resonance image (MRI) displayed an intra-and extracanalicular tumor mass, which radiologically resembled a vestibular schwannoma. Surgery was performed and histopathological studies showed an adenocarcinoma compatible with breast origin. Metastasis is a rare occurrence within the IAC and CPA. Clinical history of severe facial palsy will rise suspicion of malignant tumor in spite of the radiological findings.KEY WORDS: adenocarcinoma, breast cancer, cerebello-pontine angle, internal auditory canal, metastasis.Metástase tardia de adenocarcinoma de mama para o canal auditivo interno e ângulo ponto-cerebelar: Metástase tardia de adenocarcinoma de mama para o canal auditivo interno e ângulo ponto-cerebelar: Metástase tardia de adenocarcinoma de mama para o canal auditivo interno e ângulo ponto-cerebelar: Metástase tardia de adenocarcinoma de mama para o canal auditivo interno e ângulo ponto-cerebelar: Metástase tardia de adenocarcinoma de mama para o canal auditivo interno e ângulo ponto-cerebelar: relato de caso relato de caso relato de caso relato de caso relato de caso RESUMO -Um caso de metástase de adenocarcinoma de mama para o canal auditivo interno e ângulo pontocerebelar é apresentado. A metástase ocorreu após 16 anos do tumor primário ter sido tratado com cirurgia e radioterapia. A paciente de 66 anos foi considerada curada de sua doença primária, quando apresentou perda auditiva de progressão rápida associada a paralisia facial intermitente. Ressonância magnética demonstrou uma lesão expansiva intra e extracanalicular, cujo aspecto radiológico lembrava schwannoma do vestibular. A paciente foi submetida a cirurgia e investigação histopatológica confirmou tratar-se de metástase. Metástase é uma rara ocorrência dentro do canal auditivo interno e ângulo ponto-cerebelar. História clínica de paralisia facial severa aumentará a suspeita de lesão maligna apesar dos achados radiológicos. PALAVRAS-CHAVE: adenocarcinoma, ângulo ponto-cerebelar, canal auditivo interno, metástase, tumor de mama. The most common lesion of internal auditory canal (IAC) and cerebellopontine angle (CPA) is vestibular schwannoma, which represents 91 per cent of all cases 1 . Other lesions at this site include meningioma, epidermoid cyst, schwannoma of facial nerve, secondary cholesteatoma, lipoma, angioma and cysts. Malignant tumor account for less than one per cent of all lesions.We describe a rare case of a metastasis of a breast cancer within the IAC, which resembled radiologically a vestibular schwannoma. The tumor appeared 16 years after primary tumor had been treated successfully without signs of recurrence hitherto. CASEA 66-year-old woma...

Peripheral facial palsy caused by neoplastic meningitis

“…A total of 22 cases, including the six cases from our series, were reviewed. The primary tumor site, initial symptoms, and brain MRI findings were summarized in Table . The most frequent accompanying symptom was hearing loss, followed by pain in the head and neck region.…”

Intracanalicular facial nerve metastasis presenting as a benign tumor in the internal auditory canal

“…In our case the involvement of the intracanalicular dura was quite limited and not detected on MRI. In the two previously reported isolated intracanalicular metastasis, one lesion simulated a facial schwanoma [2], while the other diagnosed on an air-contrast CT simulated an acoustic schwanoma; moreover, postcontrast CT scan detected multiple CNS metastases [3].…”

“…Metastases involving the IAC are rare. We report here an exceptional isolated metastasis to the facial nerve without temporal bone involvement [1][2][3].…”

“…Primary metastasis to the facial nerve is a quite uncommon occurrence, with less than ten case reports available [1][2][3]. More globally, malignant disease involving the IAC accounts for less than 1% of all lesions among which metastases remain a rare occurrence [1].…”

“…The imaging reports of intracanalicular metastases are sparse [1][2][3]. Except for associated bony lytic lesions, most of the reported cases were bilateral or associated with other localizations such as cerebromeningeal metastases [3].…”