MON-919 Primary Neuroendocrine Tumor of the Central Nervous Sistem, a Case Report and Literature Review

Neuroendocrine Neoplasms are rare, with an incidence of 5 to 100,000 inhabitants, constituting 1% of all malignancies, presenting high survival rates in general, even in metastatic diseases. However, in those poorly differentiated, as in the following case, survival is around 4% in 5 years. We will describe a case of primary neuroendocrine tumor in the brain, of which is uncommon in the literature. Clinical case A 26 years women was referred to the ER of Santa Casa de São Paulo, in January 2019, to be evaluated by neurosurgery, due to progressive left hemiparesis and headache for 3 months, which got worse in 4 days. On CT scan, there was a 6 x 6 cm solid-cystic, expansive, lesion in the right frontal lobe, with perilesional edema and contralateral midline 1.3cm deviation and subfalcine herniation. Thus, the tumor was resected soon, with anatomopathological analysis showing poorly differentiated tumor of cells with scarce cytoplasm, hyperchromatic nuclei and high mitotic activity. Immunohistochemical analysis finds 50% Ki67, with focal p53, TTF1, CD99, CD 56 and synaptophysin positivity. The main hypotheses, then, consisted of Neuroendocrine Carcinoma. Four months after surgery, the patient reported worsening deficit, headache, pain, weight loss, being referred to the Emergency Room, once more. In RM an expansive lesion was found 6.6 x 4.4 cm, in the right frontoparietal surgical cavity, edema, compression and 0,4 cm midline deviation. The patient was once again submitted to emergency neurosurgery, with microsurgical resection. The pathology was identical to the previous one. We proceed with hormonal evaluation, regarding to Medular Thyroid carcinoma, Gastrinoma, Insulinoma, Pheochromocytoma, Carcinoid tumor and others. Imaging exams were also performed to investigate other primary sites: no changes in CT scan of the chest and abdomen and PET CT FDG. However, this one showed recurrence of the intracranial lesion, with three sites of involvement, all hypermetabolic: one of 4.1 x 2.9 cm (SUV 4.9) and another of 3.9 x 3.3 cm (SUV 8, 4) in the right frontoparietal region and medial nodule to the right thalamus of 1.2 cm (SUV 6.1). Patient currently maintain left hemiparesis, frequent pain, taking carbamazepine due to epileptic seizures, and considerable weight loss. She has an important limitation of daily activities and basic self-care, with 50% Karnofsky scale. Due to relapse, palliative radiotherapy was initiated in the region of the tumors. Conclusion The patient had a poor outcome in relation to cancer, with little possibility of treatment due to poor tumor differentiation and poor performance status.