CPA Melanoma

Sudden Death from Primary Cerebral Melanoma: Clinical Signs and Pathological Observations

Primary cerebral tumors rarely provoke sudden death. The incidence is often underestimated with reported frequencies in the range of 0.02 to 2.1% in medicolegal autopsy series. Furthermore, primary cerebral melanoma is an uncommon neoplasm. It represents approximately 1% of all melanoma cases and 0.07% of all brain tumors. This neoplasm is very aggressive, and its annual incidence is about 1 in 10 million people. In the present study, a 20-year-old male was admitted to hospital with vomiting, headache, paresthesia and aggressive behavior. A computed tomography (CT) scan of the head was performed showing a hyperdense nodule in the right parietal lobe with inflammation of the Silvian fissure. A complete autopsy was performed 48 h after death. A blackish material was displayed on the skull base, and posterior fossa. Microscopic examination diagnosed primary brain melanoma. A systematic review of the literature was also performed where no previous analogous cases were found. The forensic pathologist rarely encounters primary cerebral melanoma, and for these reasons, it seemed appropriate to describe this case as presenting aspecific clinical symptoms and leading to sudden unexpected death. Histopathological observations are reported and discussed to explain this surprising sudden death caused by a primary cerebral melanoma.

Bilateral Internal Auditory Canal Metastasis of Colon Carcinoma Mimicking Neurofibromatosis Type II: A Case Report and Literature Review

BACKGROUND

The vast majority of cerebellopontine angle tumors are benign with a favorable prognosis. Metastatic tumors occurring in the cerebellopontine angle are extremely rare. Herein, we report a case of colon carcinoma metastasis to the bilateral internal auditory canals.

CASE DESCRIPTION

A 59-year-old man presented with a 2-week history of binaural hearing loss. One year before admission, he was diagnosed with colon carcinoma and underwent surgical resection combined with chemotherapy. Physical examination showed complete hearing loss in bilateral ears and bilateral facial palsy. Magnetic resonance imaging of the brain revealed nodules in the bilateral internal auditory canals. Middle-ear computed tomography demonstrated soft-tissue masses extending into the bilateral internal auditory canals. A diagnosis of neurofibromatosis type II was suspected. A unilateral surgical resection of the cerebellopontine angle tumor was performed. Postoperatively, the hearing loss and facial palsy remained unchanged. Pathologic examination showed metastatic, poorly differentiated carcinoma. The patient was diagnosed with metastatic colon carcinoma in the bilateral internal auditory canals. The patient refused radiotherapy and chemotherapy. The tumor progressed rapidly, and the patient developed dysphagia and choking 1 month later. The patient died of respiratory and circulatory failure 2 months after the surgery.

CONCLUSIONS

Clinicians should be aware of metastatic tumors in the internal auditory canals. Comprehensive clinicoradiologic evaluation should be highlighted. A history of malignancy and rapidly progressive hearing loss and facial palsy may suggest the diagnosis of metastasis to the internal auditory canal. The definitive diagnosis still depends on histopathologic examination.

Melanoma Mimicking Malignant Peripheral Nerve Sheath Tumor with Spread to the Cerebellopontine Angle: Utility of Next-Generation Sequencing in Diagnosis

Cutaneous spindle cell malignancy is associated with a broad differential diagnosis, particularly in the absence of a known primary melanocytic lesion. We present an unusually challenging patient who presented with clinical symptoms involving cranial nerves VII and VIII and a parotid-region mass, which was S100-positive while lacking in melanocytic pigment and markers. Over a year after resection of the parotid mass, both a cutaneous primary lentigo maligna melanoma and a metastatic CP angle melanoma were diagnosed in the same patient, prompting reconsideration of the diagnosis in the original parotid-region mass. Next-generation sequencing of a panel of cancer-associated genes demonstrated 19 identical, clinically significant mutations as well as a high tumor mutation burden in both the parotid-region and CP angle tumors, indicating a metastatic relationship between the two and a melanocytic identity of the parotid-region tumor.

The 'full-blown' MRI of sudden hearing loss: 3D FLAIR in a patient with bilateral metastases in the internal auditory canals

We report a case of a 57-year-old man with bilateral masses in the internal auditory canal. The peculiar findings at magnetic resonance imaging with tridimensional fluid-attenuated inversion recovery sequence combined with clinical data provided new insights into understanding the pathophysiology of the hearing loss.

Primary melanoma of the petrous temporal bone

Melanoma is a malignant tumor of melanocytes that is predominantly found in the skin. In rare cases, it arises from mucosal melanocytes. We describe a case of a solitary melanoma of the petrous apex of the temporal bone in a 67-year-old woman who presented with sudden hearing loss, aural fullness, and headaches, all on the right side. Magnetic resonance imaging identified a mass located at the right petrous apex; the lesion was hyperintense on T1-weighted imaging and isointense on T2 weighting, and it enhanced brightly with gadolinium contrast. The patient underwent removal of the lesion via a transcochlear approach with facial nerve translocation. Intra- and postoperative pathology identified a poorly differentiated malignancy consistent with a melanoma. Further investigations found no evidence of metastasis. Given a concern for residual disease, the patient was treated with radiation to the primary site. To the best of our knowledge, only 1 other case of primary melanoma of the petrous apex has been described in the literature.

High rate of bilaterality in internal auditory canal metastases

PURPOSE

Presentation of three cases of metastatic carcinoma to the internal auditory canal bilaterally, as well as a systematic review of the literature regarding the characteristics of these lesions.

MATERIALS AND METHODS

Using a MEDLINE Ovid search (1946-2015), we identified and reviewed 102 cases of metastatic carcinoma to the internal auditory canal. Metrics recorded include: patient age, sex, tumor type, laterality, past oncologic history, co-occurring metastatic sites, clinical findings, radiographic findings, therapy received, and outcome. Cases of unilateral versus bilateral IAC were compared.

RESULTS

Remarkably, 52.9% reported cases of internal auditory canal metastases have bilateral occurrence. The most common primary tumor sites for internal auditory canal metastases were lung (21.2%), skin (18.6%), and breast (16.7%), with lung and skin cancers having the highest rates of bilateral metastasis. Meningeal metastasis occurred at a much higher rate in bilateral cases (47.2%) versus unilateral cases (8.5%). Brain parenchymal metastasis also occurred at a higher rate in bilateral cases (38.2%) versus unilateral cases (19.2%). Outcomes for cases of internal auditory canal metastases are generally poor, with 56.3% of unilateral cases and 86.1% of bilateral cases reporting patient death within 5 years from diagnosis.

CONCLUSIONS

In cases of internal auditory canal metastasis, clinicians should carefully assess for not only contralateral disease but also additional metastatic disease of the central nervous system. Rapid-onset hearing loss, tinnitus, vertigo, or facial palsy should raise suspicion for internal auditory canal metastasis, particularly in patients with a known oncologic history.

Peripheral facial palsy caused by neoplastic meningitis

OBJECTIVES/HYPOTHESIS

To describe the clinical presentation of peripheral facial palsy caused by neoplastic meningitis.

STUDY DESIGN

Retrospective case series.

METHODS

Retrospective review, including accompanying symptoms and magnetic resonance imaging (MRI) findings.

RESULTS

Between January and December 2011, six patients were diagnosed with peripheral facial palsy caused by neoplastic meningitis. The patient age at presentation ranged from 56 to 77 years. The tumor origins were as follows: malignant lymphoma (n = 3), lung cancer (n = 2), and kidney cancer (n = 1). In three patients, sudden sensorineural hearing loss accompanied the facial palsy. Three patients were judged to be tumor-free at the onset of the facial palsy. In two patients, the malignancy was not diagnosed at the onset of facial palsy and hearing loss. Only one patient was diagnosed as having a tumor at the onset of the facial palsy. On the MRI, a mass lesion was detected in the internal auditory canals (IAC) of four patients; one had a solitary IAC tumor. In this patient, the diagnosis required a histopathological study using a translabyrinthine approach. In the other two patients, the facial nerve was enhanced with gadolinium, but it was difficult to differentiate the observed condition from Bell's palsy. In these patients, repeated cytological studies led to the correct diagnoses.

CONCLUSIONS

The clinical symptoms and MRI findings of peripheral facial palsy caused by neoplastic meningitis sometimes mimic those of benign facial palsy.

Primary melanoma of the cochlea with cerebellopontine extension and leptomeningeal spread

BACKGROUND

Less than 1 per cent of tumours occurring in the region encompassing the internal auditory canal and the cerebellopontine angle are malignant. Primary central nervous system melanomas arising from this region are exceptionally rare and are often initially misdiagnosed as acoustic neuromas.

METHODS

We present a 71-year-old man with acute vestibular disturbance and unilateral hearing loss. Magnetic resonance imaging demonstrated a mass, thought to be a cochlear nerve schwannoma, involving the cochlea and the internal auditory canal. At surgery, a pigmented mass adherent to the facial nerve was visualised, and the observed histopathology was consistent with a malignant melanoma. No extracranial site for the primary tumour was found, suggestive of a primary central nervous system melanoma.

RESULTS

Despite surgical resection and adjuvant radiotherapy, the patient re-presented with extensive leptomeningeal disease 16 months later.

CONCLUSION

Malignant tumours in the internal auditory canal and cerebellopontine angle region are rare. Early diagnosis and management are aided by recognition of characteristic factors such as a history of prior malignancy, atypical magnetic resonance imaging findings and accelerated audiovestibular symptoms. Despite the presented patient's outcome, total surgical resection with post-operative radiotherapy remains the recommended treatment.

Metastatic tumours mimicking vestibular schwannoma

In this review of the literature we discuss the rare occurrence of metastatic tumours mimicking bilateral vestibular schwannoma and present an own case with pancreatic signet-ring cell carcinoma as primary tumour.

Asymptomatic cerebellopontine angle and lateral ventricle metastases from renal cell carcinoma: case report and literature review

Tumors rarely metastasize to the cerebellopontine angle. We report the first instance of simultaneous metastasis of renal cell carcinoma to the cerebellopontine angle and the lateral ventricle. A 51-year-old man presented with anemia and fatigue owing to stomach metastases from renal cell carcinoma 8 years after undergoing partial left nephrectomy for grade II clear cell renal carcinoma and radical right nephrectomy for grade III clear cell renal carcinoma. He also suffered metastases to the lung, both adrenal glands, the L-3 vertebra, and the brain (asymptomatic, but revealed by magnetic resonance imaging): a 1-cm (maximum diameter) mass in the left medullary cistern and a 2-cm (maximum diameter) mass in the right lateral ventricle trigone. Both brain lesions were treated with stereotactic radiosurgery, followed by gross-total resection of the right trigonal mass 7 months later. Both tumors shrank significantly, but the patient died from progressive systemic cancer 1 year after diagnosis of brain metastasis.

Pathology of the vestibulocochlear nerve

Imaging of the vestibulocochlear nerve has evolved dramatically over the past few decades. The imaging specialist now is involved in the diagnosis of far more diagnostic entities than ever before. With this increased involvement comes the responsibility to increase collective knowledge regarding the pathophysiology of these diagnostic entities. This article is organized in a conventional way and covers congenital deformity of the internal auditory canal, neoplastic and pseudoneoplastic lesions, with special detailed emphasis on schwannoma of the eight cranial nerves (acoustic neuroma), nonneoplastic IAC/CPA pathology, including vascular loops, and numerous additional differential diagnostic entities, with particular emphasis on non-neoplastic meningeal disease. Lesions of the auditory pathway and an overview of cochlear implant surgery are also included in this discussion.

Bilateral malignant melanoma metastases to the internal auditory canal/cerebellopontine angle: surgical management and preservation of function

✓Although intracranial metastases of malignant melanomas are common, localization at the cerebellopontine angle (CPA) or in the internal auditory canal (IAC) is rare, and bilateral presentation especially so. We present the case of a 46-year-old Caucasian woman with bilateral IAC/CPA lesions and a prior history of malignant melanoma on the right leg. During preoperative investigations, the presence of the bilateral IAC/CPA lesions along with several radiologically identified lesions along the neural axis led to the suspicion that she had neurofibromatosis Type 2 despite her history of malignant melanoma and the lack of characteristic skin lesions and family history. Histopathological analysis of the resected lesion confirmed the intraoperative diagnosis of bilateral CPA malignant melanoma metastases. Surgical removal of the tumors via the retrosigmoid approach with preservation of normal bilateral facial nerve function and unilateral serviceable hearing, combined with control of the systemic disease, provided this patient with a near-normal quality of life for at least 42 months after the initial diagnosis of melanoma.

Bilateral Cerebellopontine Angle Metastatic Melanoma: A Case Report

Although melanoma accounts for approximately 1% of all malignancies, melanoma metastases to the cerebellopontine angles (CPAs) are exceedingly rare. Here we describe a patient with melanoma metastases to the internal auditory canals and CPAs who presented with a remote history of cutaneous melanoma. This patient had a rapidly progressive hearing loss, vestibulopathy, and facial nerve dysfunction. Magnetic resonance imaging demonstrated bilateral, enhancing CPA lesions but was otherwise nonspecific. The diagnosis required a careful history, unilateral surgical resection for tissue acquisition, and histopathologic confirmation. A search for primary cutaneous melanoma at the time of presentation was negative. However, the history of cutaneous melanoma 8 years earlier distinguishes this patient's metastatic disease from solitary primary intracranial melanoma, an equally rare disease. Treatment consists of surgical excision, radiation, chemotherapy, and immunotherapy. The prognosis for patients with melanoma metastases is generally poor, but isolated reports of long-term survival have been described. Metastatic disease to the CPAs must be included in the differential diagnosis for any patient presenting with rapid-onset VIIth or VIIIth cranial nerve symptoms.