Role of Adjuvant Thoracic Radiation Therapy and Full Dose Chemotherapy in pN2 Non-small Cell Lung Cancer: Elucidation Based on Single Institute Experience

The efficacy of postoperative radiotherapy for patients with non-small cell lung cancer: An updated systematic review and meta-analysis

The controversy over the efficacy of postoperative radiotherapy (PORT) has existed for a long time. The present study reassessed the overall survival (OS) and disease-free survival (DFS) data to investigate whether PORT can improve survival in resectable non-small cell lung cancer (NSCLC) patients. The following databases were used to perform literature search: PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Embase (from January 1, 1986 to July 5, 2021). The results of overall survival (OS) and disease-free survival (DFS) were calculated as hazard ratio (HR). Confidence intervals are chosen with 95% confidence intervals. A total of 12 RCTs and 19 retrospective cohort studies were found to meet the inclusion criteria. A significant DFS improvement was detected in the PORT group (4111 patients from 15 studies), although statistical difference was not detected for OS between the non-PORT and PORT groups (31 studies, 49,342 total patients). PORT prolonged OS in patients undergoing PORT plus postoperative chemotherapy (POCT) and in pN2 patients. Patients with a median radiation dose of 50.4 Gy and a median radiation dose of 54 Gy had a better OS after PORT. However, if the total radiotherapy dose went up to 60 Gy, PORT increased the risk of death in NSCLC patients. Significant difference in OS was not found in the results of studies with regard to treatment methods, pathologic stages, study type, radiation beam quality, and radiation dose. Patients undergoing postoperative chemoradiotherapy and pN2 patients can benefit from PORT. Patients exposed to median radiation doses of 50.4 and 54 Gy demonstrated relatively good efficacy. For patients with non-small-cell lung cancer, PORT has not been proven to extend OS, but its effect on DFS remains strong.

The effect of adjuvant chemoradiotherapy on survival after R0 resection for stage III-N2 nonsmall cell lung cancer: A meta-analysis

BACKGROUND

Adjuvant chemotherapy is still the standard treatment for stage III-N2 nonsmall cell lung cancer after R0 resection, and it is still controversial whether conventional adjuvant radiotherapy is needed. We used meta-analysis to try to answer whether adjuvant postoperative chemoradiotherapy (POCRT) can bring survival benefits to patients with stage III-N2 nonsmall cell lung cancer after R0 resection.

METHODS

Up to June 25, 2021, the databases of PubMed, Embase, Cochrane Library, CNKI, and Wanfang were searched, and clinical studies on POCRT for stage III-N2 nonsmall cell lung cancer were included. RevMan5.4 software was used for meta-analysis.

RESULTS

A total of 8959 patients were included in 5 randomized controlled trials and 17 retrospective studies. The results of the meta-analysis showed that POCRT could improve 3 and 5 years overall survival (OS) rate (OR = 1.52, 95%CI: 1.05-2.20; OR = 1.30, 95%CI: 1.16-1.46), 3 and 5 years disease-free survival (DFS) rate (OR = 1.34, 95%CI: 1.01-1.76; OR = 1.74, 95%CI: 1.43-2.12), and 5-year locoregional recurrence-free survival (LRFS) rate (OR = 2.69, 95%CI: 1.76-4.11) in patients with stage III-N2 nonsmall cell lung cancer compared with adjuvant postoperative chemotherapy (POCT) alone. But could not improve 5-year distant metastasis-free survival (DMFS) rate (OR = 1.14, 95%CI: 0.52-2.52). The results of subgroup analysis showed that postoperative sequential chemoradiotherapy could improve the 3 and 5 years OS rate (OR = 2.06, 95%CI: 1.22-3.46; OR = 1.39, 95%CI: 1.21-1.59). Three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT) can improve the 3 and 5 years OS rate (OR = 1.80, 95%CI: 1.09-2.99; OR = 1.31, 95%CI: 1.04-1.66). In addition, POCRT could improve the 3-year OS rate (OR = 1.88, 95%CI: 1.21-2.92) in patients with N2 single-station lymph node metastasis compared with POCT alone.

CONCLUSION

Compared with POCT alone, adjuvant POCRT can significantly improve the overall survival rate of patients with NSCLC after R0 resection of stage III-N2, especially in patients with N2 single-station lymph node metastasis. Accurate radiotherapy techniques such as 3DCRT or IMRT are recommended, and postoperative sequential chemoradiotherapy is the best treatment mode.