The results and prognosis of different treatment modalities for solitary metastatic lung tumor from nasopharyngeal carcinoma: a retrospective study of 105 cases.

Background and Objective: Nasopharyngeal carcinoma (NPC) is known for its propensity for distant metastases. Lung metastasis is one of the most important causes of death for patients with NPC. Solitary metastatic lung tumor from NPC is a distinctive group associated with a better survival. This study was to find a more effective treatment modality and prognostic factors for the group.
Methods: Clinical data of 105 cases of solitary metastatic lung tumor from NPC were retrospectively analyzed. Survival rate was calculated by the Kaplan-Meier method. The difference of survival between the patients treated by different modalities was evaluated by the log-rank test. The Cox univariate and multivariate analyses of gender, age, pathologic type, stage, adjuvant chemotherapy, evaluation of treatment for NPC, disease-free interval, size of metastatic tumor, pulmonary hilar and/or mediastinal lymph node metastasis, treatment modalities, recurrent distant metastases and/or relapse of NPC were conducted.
Results: The local control rate was 53.8% in chemotherapy group, 88.0% in radiotherapy ± chemotherapy group, and 96.4% in operation ± chemotherapy group (P < 0.01). The most promising progression-free survival (PFS) and overall survival (OS) were obtained with operation ± chemotherapy and followed by radiotherapy ± chemotherapy. Both of them showed much better efficacy than chemotherapy (P < 0.001). The Cox multivariate analysis showed that recurrent distant metastases and/or relapse of NPC affected the survival (OR = 2.087, 95% CI = 1.277-3.410, P = 0.003). The T stage of NPC, size of metastatic tumor, hilar and/or mediastinal lymph node metastasis, and the treatment modality were independent prognostic factors.
Conclusions: Operation ± chemotherapy and radiotherapy ± chemotherapy are better treatment of solitary metastatic lung tumor from NPC, which could improve the local control and prolong the PFS and OS. Chemotherapy is recommended for patients with higher T stage of NPC, size of metastatic tumor ≥ 3 cm, pulmonary hilar and/or mediastinal lymph node metastasis.