Background: The role of chemotherapy given concurrently with thoracic three-dimensional radiotherapy for stage IV non-small cell lung cancer (NSCLC) is not well defined. We performed this study to investigate overall survival and toxicity in patients with stage IV NSCLC treated with this modality.
Methods: From 2003 to 2010, 201 patients were enrolled in this study. All patients received chemotherapy with concurrent thoracic three-dimensional radiotherapy. The study endpoints were the assessment of overall survival (OS) and acute toxicity.
Results: For all patients, the median survival time (MST) was 10.0 months, and the 1-, 2- and 3-year OS rates were 40.2%, 16.4%, and 9.6%, respectively. The MST was 14.0 months for patients who received a total radiation dose ≥63 Gy to the primary tumor, whereas it was 8.0 months for patients who received a total dose <63 Gy (P = 0.000). On multivariate analysis, a total dose ≥63 Gy, a single site of metastatic disease, and undergoing ≥4 cycles of chemotherapy were independent prognostic factors for better OS (P = 0.007, P = 0.014, and P = 0.038, respectively); radiotherapy involving metastatic sites was a marginally significant prognostic factor (P = 0.063). When the whole group was subdivided into patients with metastasis at a single site and multiple sites, a higher radiation dose to the primary tumor remained a significant prognostic factor for improved OS. For patients who received ≥4 cycles of chemotherapy, high radiation dose remained of benefit for OS (P = 0.001). Moreover, for the subgroup that received <4 chemotherapy cycles, the radiation dose was of marginal statistical significance regarding OS (P = 0.063). Treatment-related toxicity was found to be acceptable.
Conclusions: Radiation dose to primary tumor, the number of metastatic sites, and the number of chemotherapy cycles were independent prognostic factors for OS in stage IV NSCLC patients treated with concurrent chemoradiotherapy. In addition to systemic chemotherapy, aggressive thoracic radiotherapy was shown to play an important role in improving OS.
Trial registration: Registered on (ChiCTR-TNC-10001026).