Cisplatin and 5-fluorouracil as induction chemotherapy followed by radiation therapy in metastatic squamous cell carcinoma of an unknown primary tumor localized to the neck. A phase II study.

12 patients with metastatic squamous cell carcinoma of an unknown primary tumor localized to the neck were treated with induction chemotherapy and radiotherapy. Median age was 54 years (range, 39-68 years) and male to female ratio was 2:1. Five (42%) patients had N3 disease and 7 (58%) had N2 disease. Induction chemotherapy consisted of cisplatin 60 mg/m2, days 1 and 2 and 5-fluorouracil (5-FU), 500 mg/m2, days 3 and 4. Cycles were repeated every 4 weeks to a total of 3 cycles. After 4 weeks rest, patients underwent radiation therapy. It was given to all possible sites of the primary tumor (nasopharynx, pyriform sinus, and the base of the tongue). The radiation therapy dosage planned to the whole neck, nasopharynx, and supraclavicular area was 45 Gy in 24 daily fractions in 5 weeks, increasing to 60-70 Gy to the metastatic site. We observed 9 (75%) complete responses and 1 (8%) partial response. 7 (58%) patients are currently with no evidence of disease. Median survival time for all patients is 36 months (range, 14+ to 56 months), while median survival time for N3 patients was 32 months (range, 26-56 months). Toxicities were predominantly mild to moderate nausea and vomiting and mucositis. This combined modality appears to be effective and feasible in treatment of metastatic squamous cell carcinoma of an unknown primary tumor localized to the neck.