Pattern of Local Failure and its Risk Factors of Locally Advanced Non-small Cell Lung Cancer Treated With Concurrent Chemo-radiotherapy.

Background/aim: The treatment outcome of locally advanced non-small cell lung cancer (LA-NSCLC) has been improved over the past years but local failure is still common for these patients. The purpose of this study is to analyze the pattern of local failure and its risk factor of concurrent chemo-radiotherapy (CCRT) for locally advanced LA-NSCLC.

Patients And Methods: We evaluated 77 patients treated with CCRT for LA-NSCLC from July 2007 to December 2017 at our institution. Most of the patients were treated with 60 Gy in 30 fractions of radiotherapy and concurrent chemotherapy. The median follow-up time was 26 months.

Results: Among the 77 patients, 50 developed progressive disease during follow-up, including 14 with only local recurrence (LR), 10 with only distant metastasis and 26 with both. Of the 14 patients with only LR, 12 had primary tumor recurrence and 2 had recurrence in lymph nodes. A primary tumor volume of 50 cm3 was identified as the optimal cut-off value that was significantly correlated with primary tumor recurrence and overall survival.

Conclusion: Primary tumor recurrence without lymph node and distant metastasis was observed in 12 patients (16%). Primary tumor volume of 50 cm3 was the optimal cut-off value for the prediction of primary tumor recurrence.