[Metachronous cancers after treatment for undifferentiated nasopharyngeal carcinoma].

Objective: To collect second cancers occurring in the head and neck area after treatment by chemotherapy and/or radiotherapy for undifferentiated nasopharyngeal carcinoma in Tunisia.
Patients and Methods: This is a retrospective study of patients developing second cancers after treatment for nasopharyngeal UCNT by radiotherapy and/or chemotherapy. To be retained in this study, second tumour had to be histologically different from the initial UCNT, localised in the irradiated area and occurring after a minimal delay of 3 years.
Results: We collect 11 cases of second cancers occurring among 2346 patients treated from 1984 to 2001 in Tunisia (0.46%). Patients have been treated for nasopharyngeal UCNT mainly advanced T3-T4 (72%) or N2-N3 (63%). Median age was 20 years (11 to 48) with a sex-ratio of 0.3 (3 M/8 F). Treatment protocol included primary chemotherapy in 4 cases (adriamycin-cisplatin) or adjuvant (in 4) associated to the loco-regional irradiation at a mean dose of 72 Gy (70 to 75). Median delay of second cancer occurrence was 9 years (3 to 17). Tumors were epidermoid carcinomas in 4 cases, fibrosarcomas (2), osteosarcomas (2), glioblastoma (1) and basocellular carcinomas in 2. Second tumors have been treated by surgery alone in 4 cases and chemotherapy alone in 7 patients. No patient have been reirradiated. Median survival was 17 months, 4 patients died and 7 are still alive including 4 in complete remission (24+, 36, 36 and 48+ months) and 3 with progressing disease (8, 16 and 18 months).
Conclusion: Even very rare, second cancers after treatment for UCNT need to be detected and have a poor prognosis.