UNDIFFERENTIATED CARCINOMA OF THE MAJOR SALIVARY-GLANDS

BAGKGROUND. Undifferentiated carcinoma of the salivary glands is a rar e disease, the incidence of which is highest among the Inuit of GreenI and and North America. It was demonstrated to be closely related to Ep stein- Barr virus (EBV) infection. However, the relation of EBV to thi s tumor has not been studied to any great extent here in Taiwan becaus e of the small number of cases. METHODS. Twelve cases of undifferentia ted carcinoma of the salivary glands from the period 1977-1996 were re trieved from the cancer registry at National Taiwan University Hospita l. The clinical data were analyzed retrospectively based on the medica l records. Eleven formalin fixed, paraffin embedded tissue sections we re used for in situ hybridization with an antisense probe complementar y to EBV-encoded RNA 1 (EBER1). RESULTS. Ten of 12 tumors originated f rom the parotid gland and 2 from the submandibular gland. The patients ' ages ranged from 22 to 63 years, with an average of 38.1 years. One patient was lost to follow-up, 2 patients died of metastatic disease, and the remaining 9 patients were all alive and disease free at last f ollow-up. The actuarial 5-year survival rate was 79.8%. In situ hybrid ization demonstrated EBER1 in 9 of the undifferentiated carcinomas wit h lymphoid stroma, but EBER1 was not demonstrated in the other 2 tumor s without lymphoid stroma. CONCLUSIONS. Undifferentiated carcinoma wit h lymphoid stroma of the major salivary glands is closely associated w ith EBV. The mainstay of treatment is surgery and postoperative radiot herapy. The outcomes in this series were good except for two elderly p atients who died of rapid and progressive distant metastases. (C) 1997 American Cancer Society.