| Additional Info: |
After positive biopsies show recurrent tumor, the patient underwent a third operation, a total rhinectomy with left thigh split thickness skin graft and submental node dissection. This was her third surgery.
As shown, this poorly differentiated tumor is seen infiltrating into both bone and cartilage. This is a sinonasal undifferentiated carcinoma (SNUC). As recognized by the WHO, SNUC is a clinicopathologically distinct carcinoma with highly aggressive behavior, uncertain histogenesis, often abruptly presenting with locally extensive disease.
SNUC is an uncommon tumor with fewer than 100 reported cases. It is more common in men with median presentation in the 6th decade. It presents with nasal obstruction, epistaxis, proptosis, visual disturbances, facial pain, and symptomatic facial nerve involvement.
SNUC is thought to arise from the Schneiderian epithelium (ectodermal in derivation). Immunohistochemistry suggest a possible link to Olfactory epithelium. SNUC may occupy a histopathologic medium between poorly differentiated SCC and neuroendocrine carcinoma.
There are no known etiologic factors. Some cases are positive for EBV RNA, but majority of cases are negative. Some cases reported following radiation for nasopharyngeal carcinoma. Association with smoking and nickel exposure has been reported. RB gene deletion has been implicated in development of SNUC.
|