A Primary Capicua Transcriptional Repressor (CIC)-Rearranged Round Cell Sarcoma of the Neck: A Case Report and Literature Review

This is a case report of a CIC-rearranged sarcoma located in the neck. Our patient was a 36 year-old-woman with unremarkable past medical history who presented with a left lateralized neck mass evolving for one year without other signs. The physical examination showed a bulky left cervical mass of 12cm long axis, with infected and necrotic areas. There was no palpable lymph nodes. A computed tomography (CT) scan was performed and confirmed the suspicious nature of the lesion and did not show distant metastasis. Histology (completed with Fluorescence in situ Hybridization (FISH) analysis) of a biopsy confirmed the diagnosis of round cell sarcoma with CIC rearrangement. As the tumor was unresectable, we started with chemotherapy but the tumor progressed after three cycles. The patient could not receive a second line chemotherapy because of the deterioration of the general condition and died after 1 month. In conclusion, CIC-rearranged sarcoma is a rare tumor and has a poorer prognosis than the classic Ewing Sarcoma (ES). Its treatment is still challenging. More research is needed to establish the optimal treatment strategies.