CANCERS IN MULTIPLE PRIMARY SITES

Seventy-six patients with multiple primary cancers have been found among 9180 cancer patients admitted to the Center of Oncology and Nuclear Medicine, Okmeydani Hospital, Istanbul, Turkey between 1980 and 1984. Overall incidence of multiple primary cancers (MPC) among all cancer patients was 0.83%. The majority of the patients were male in both MPC and all patients, i.e. 64.5% and 63.1%, respectively. In MPC patients, the great majority of the patients was in the 51-70 years age group (57.9%) at the time of initial cancer diagnosis. Combination of larynx cancer and lung cancer was the most commonly seen combination. It was followed by lip cancer-larynx cancer (6.6%), skin cancer-larynx cancer and skin cancer-lung cancer (5.3%), breast cancer-ovary cancer and breast cancer-endometrium cancer (4%) combinations. Larynx cancer was the most commonly seen multiple primary cancer component in all patients (46%) and in male patients (61.2%). It was followed by lung cancer, i.e. 39.5% in all patients and 55.1% in male patients. In female patients, breast cancer was a component in 63% of the cases. In eleven patients, two cancers were diagnosed concurrently. In other cases, the interval between two cancers varied between 1 month and 30 years. The mean interval was 4.1 +/- 0.6 years (median 3.0 years). In 62% of the cases, the interval between two canters was shorter than 3 years. Smoking rate was 75.5% in male patients whereas it was only 18.5% in females. In larynx cancer-lung cancer patients, smoking rate was 81.2% and reached 83.3% when lip cancers were included. Mean follow-up after second primary cancer was 1.5 +/- 0.2 years (median of 9 months, range 0.1-11 years). Seventeen patients were found to be disease free at their last followup (22.4%). The prognosis for female patients with MPC appeared to be better (p = 0.055). Age of the patients at the time of initial cancer diagnosis was another important factor to predict the overall prognosis in MPC. Patients less than or equal to 50 years old at the time of first cancer diagnosis did significantly better than the other patients, p = 0.001. Time interval between two primary cancers was significantly correlated with the overall survival. Patients who developed a secondary primary tumor within two years after the first one did significantly worse, p < 0.001.