CNSC-100. DE NOVO PRIMARY INTRACRANIAL SQUAMOUS CELL CARCINOMA MANAGED WITH MULTIMODALITY TREATMENT: A CASE REPORT

Abstract Primary intracranial squamous cell carcinoma (SCC) is a rare disease entity that is usually derived from the malignant transformation of an epidermoid cyst. Even less common is the primary intracranial SCC that arises de novo, with only 11 patients reported in literature. Most patients are managed with surgery and radiotherapy. We report a 37-year-old female who presented with a 3-year history of ear fullness and decreased hearing on the right, initially diagnosed and managed as chronic sinusitis. Three years from the onset of otologic symptoms, she also experienced right hemifacial numbness and paresthesia. A cranial magnetic resonance imaging (MRI) with contrast revealed a right middle cranial fossa mass, along the right petroclival region, for which a meningioma was initially considered. She underwent right pterional craniotomy and excision of tumor. Histopathology results showed a non-keratinizing squamous cell carcinoma of the undifferentiated type. Two months after the surgery, she developed new neurologic symptoms of right peripheral facial palsy and gait imbalance. Neuroimaging confirmed tumor recurrence. An MRI of the nasopharynx, transnasal flexible endoscopy, and a whole-body positron emission tomography and computed tomography (PET/CT) scan did not show evidence of a tumor elsewhere. She underwent chemotherapy with cisplatin, etoposide, and cyclophosphamide (CCE protocol) for four cycles followed by radiation therapy, with a significant decrease in the size of the tumor and improvement of her craniopathies. The patient remains stable three months from completion of treatment. This case illustrates a rare case of primary intracranial SCC arising de novo and the success of multi-modality treatment. Due to the rarity of this disease entity and with limited literature available, the standard treatment modality is yet to be identified. More studies are needed to optimize the management of this rare and aggressive tumor.