Oligometastases in AJCC stage IVc nasopharyngeal carcinoma: A subset with better overall survival.

Background The purpose of this study was to analyze the patterns of metastasis and therapeutic approaches in American Joint Committee on Cancer (AJCC) stage IVc nasopharyngeal carcinoma (NPC). Methods A retrospective analysis of 263 patients with stage IVc NPC revealed the incidence of bone, liver, and lung metastases was 67.7%, 32.3%, and 16.0%, respectively. All patients received chemotherapy; 160 patients received radiotherapy (RT) to the primary tumor. Results The factors associated with poor overall survival (OS) were Karnofsky Performance Scale (KPS) ≤70, liver metastasis, multiple-organ metastasis, ≥6 lesions, no RT to the primary tumor, and <4 chemotherapy cycles. Two subgroups of M1 disease were divided into: M1a (oligometastases) = single-organ metastases or 1 to 5 lesions; and M1b = multiple-organ metastases or ≥6 lesions. The 5-year OS rates for M1a and M1b were 38.7% versus 7.0%, respectively. Conclusion Patients with oligometastases have significantly better OS than patients with widespread metastases. Long-term disease-free survival can be achieved in selected patients with oligometastases after systemic chemotherapy and definitive RT. © 2016 Wiley Periodicals, Inc. Head Neck 38:1152–1157, 2016