Intracranial metastasis from primary spinal primitive neuroectodermal tumor
A 22-year-old female presented with a one month history of headache and left hemiparesis in March 2010. On examination, she had grade 4/5 power in left upper and lower limbs. Contrast enhanced computed tomography (CECT) of the brain revealed enhanced hyperdense solitary right parietal parasagittal tumor []. In April 2003, she was diagnosed to have primary spinal PNET at C6-D2 level with dumbell like extension into the thoracic cavity [Figures and ]. She underwent right posterolateral thoracotomy and excision of the tumor at another institution. Pathological examination of the tumor confirmed the tumor was pPNET. Immunohistochemistry (IHC) for CD99 was positive. Surgery was followed by radiotherapy (with 57.6Gy) to the right neck, superior mediastinum and the right upper lung. Chemotherapy with ifosfamide, adriamycin, and etoptoside was administered for seven cycles. Positron emission tomography (PET) scan done 5 years after the treatment for spinal PNET, in December 2008 revealed no residual lesion or metastasis [].\nRight frontoparietal parasagittal craniotomy was done for the solitary parietal parasagittal tumor detected by CECT. It was found to be highly vascular and was present adjacent to the motor cortex, infiltrating into the dura. Near-total excision of the tumor was done leaving a thin rim of tumor along the superior sagittal sinus. The infiltrated dura was resected and duraplasty done.\nHistopathological examination revealed a densely cellular infiltrate of loosely cohesive, mitotically active cells arranged in sheets and lobules with minimal intervening stroma []. The tumor also shows perivascular necrosis, with pseudorosette formation and organized hemorrhage. The individual cells had scanty cytoplasm, with round to oval nuclei, coarse chromatin and conspicuous nucleoli in some cells. Tumor cells showed focal Periodic Acid Schiff (PAS) positivity. IHC stains for tumor cells showed membranous positivity for CD99 []. Fluorescent insitu hybridization analysis (FISH) for translocation (11; 22) (q24; q12) was not done in this case, as it was not available locally. These findings were consistent with pPNET/Ewing's sarcoma (ES).\nThe patient had mild worsening of motor power on the left side to 3/5 after surgery, which gradually recovered in two months. She received postoperative radiotherapy of 40 Gy/250 cgy/16 Frs to brain and five cycles of chemotherapy with ifosfamide and etoposide. CECT scan of brain was done nine months after surgery; it showed no residual or recurrent disease []. Follow-up visit at 20 months after the surgery showed that she was normal with no recurrence of disease.