Survival statistics for multiple primaries in head and neck cancer.

The recognition of a second primary carcinoma in a patient with known head and neck cancer is considered a poor prognostic sign. However, its true implication for patient survival is not known. A retrospective 10-year study showed that second primary malignancies developed in 207 of 875 patients. Second primary malignancies were most commonly associated with glottic index tumors, followed by floor of mouth tumors. The second primary was most likely to occur at a time interval of 1.5 years from diagnosis of the index tumor. Second primary neoplasms were more likely to develop in patients whose original head and neck tumor was stage I or II, or whose histopathology showed well or moderately well differentiation. Patients with head and neck cancer in whom a second upper aerodigestive tract tumor develops have a 75% chance of 1-year survival, but only a 25% chance of 5-year survival. The average time from diagnosis of second primary to the time of death was 2.3 years. If we are to increase the survival time of our patients with head and neck cancer, we must consider that a second primary will develop in one of four patients. We must therefore consider the high risk of second primary malignancy when formulating the original treatment plan for a patient manifesting his or her first head and neck cancer.