Sinonasal Nuclear Protein Testis Midline Carcinoma: Case Report with a Review of the Literature

Background Nuclear protein testis (NUT) midline carcinoma is a rare undifferentiated epithelial malignancy of the upper midline structures. Most often arising in the thorax or head and neck in young patients, NUT carcinoma is highly aggressive and associated with high mortality. Despite treatment, the average survival time is less than 1 year, with overall survival of 19% at 2 years. There is little consensus on the optimal treatment regimen, including the role for surgery. We report two successful cases of sinonasal NUT midline carcinoma treated with upfront surgery followed by adjuvant chemoradiation.

Case Patient 1 is a 43-year-old man who presented with 1 month of nasal congestion. Clinical examination revealed edema and polypoid material in the middle meatus. Office biopsy was most consistent with squamous cell carcinoma including bony infiltration and perineural invasion. Imaging revealed erosion of the midportion of the inferior turbinate. The patient was taken to the operating room for resection; final pathology revealed NUT midline carcinoma of left maxilla. The patient was taken for subsequent surgery to provide wider oncologic margins. The patient underwent subsequent radiation and low-dose cisplatin.

Patient 2 is a 32-year-old woman who presented at 26 weeks’ gestation with unilateral nasal obstruction and sinus pressure. Clinical examination showed a large exophytic mass filling the right nasal cavity. Imaging demonstrated a right sinonasal mass with gross orbital bone and skull base invasion. Office biopsy was most consistent with squamous cell carcinoma. The patient underwent surgical resection including orbital exenteration, which achieved wide local excision and oncologic margins. Final pathology revealed NUT midline carcinoma. The patient received adjuvant radiation and cisplatin. Both patients are doing well more than 3 years after completing treatment without signs of recurrence.

Discussion Optimal management of the newly described NUT midline carcinoma remains an area of active research. Patients of any age can be affected and clinical manifestations remain poorly defined. Previously classified as poorly differentiated or undifferentiated carcinoma, NUT midline carcinoma continues to be a challenge to identify histologically, with tumors often initially misidentified on office biopsy. In the face of rapid disease progression, treatment regimens for NUT midline carcinoma remain broadly variable. Although most patients undergo trimodality therapy, the role of surgery remains poorly defined; recurrences are common, with surgical margins often widely involved by the tumor. We present two cases of young patients who received complete oncologic resection and timely adjuvant chemoradiotherapy with successful disease control. We discuss the clinical nuances of evaluation, pearls of optimizing surgical resection and adjuvant therapies, and consider current research of this poorly understood malignancy.