Double and multiple primary cancers in an adult head and neck radiation therapy clinic.

The records of 321 consecutive patients referred to the Radiation Oncology Center between January 1, 1980, and December 30, 1982, for head and neck cancers were reviewed to determine the incidence of other cancers. Two hundred sixty-two patients have had a single primary cancer in the head and neck region. Fifty-nine patients (18%) have had more than one cancer. These 59 patients have had 68 other cancers. While other head and neck cancers lead the list of second primaries, second cancers also occurred in the esophagus, lung, genitourinary system and elsewhere. Twenty cancers had occurred prior to the patient developing head and neck cancer. Thirty-two cancers were synchronous with the head and neck cancer; 16 have been metachronous. These numbers emphasize that patients with head and neck cancers are in a cancer-prone group that develops a variety of other cancers. These findings have important implications in work-up, radiation treatment planning, treatment goals and follow-up programs.