The records of 759 patients with nasopharyngeal carcinoma were reviewed. Fifteen of them also suffered from another malignant neoplasm. All patients had histological confirmation of the nasopharyngeal carcinoma and the other malignant neoplasm. There was no predilection for the second malignant neoplasms to arise from the bronchus. Although the observed number of second malignant neoplasms was not significantly different from the expected number (p greater than 0.05) computed by the patient-month approach, in 1 patient the second malignant neoplasm may be causally related to the previous treatment of nasopharyngeal carcinoma by radiotherapy.