Substantial imbalance that is never eliminated with propensity score matched analyses in comparing surgery to stereotactic body radiotherapy for patients with early-stage non-small cell lung cancer

Local Control Correlates with Overall Survival in Radiotherapy for Early-stage Non-small Cell Lung Cancer: A Systematic Review

PURPOSE

Local control (LC) is an important outcome of local cancer therapy, besides overall survival (OS). We conducted a comprehensive literature search to investigate whether a high LC rate contributes to good OS in radiotherapy for early-stage non-small cell lung cancer (ES-NSCLC).

MATERIALS AND METHODS

Studies in patients receiving radiotherapy for peripheral ES-NSCLC, mainly staged as T1-2N0M0 were included for a systematic review. Relevant information was collected including, dose fractionation, T stage, median age, 3-year LC, cancer-specific survival (CSS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and OS. Correlations between outcomes and clinical variables were evaluated.

RESULTS

After screening, 101 data points from 87 studies including 13,435 patients were selected for the quantitative synthesis. Univariate meta-regression analysis revealed that the coefficients between the 3-year LC and 3-year DFS, DMFS, CSS, and OS were 0.753 (95% confidence interval (CI): 0.307-1.199; p<0.001), 0.360 (95% CI: 0.128-0.593; p=0.002), 0.766 (95% CI: 0.489-1.044; p<0.001), and 0.574 (95% CI: 0.275-0.822; p<0.001), respectively. Multivariate analysis revealed that the 3-year LC (coefficient, 0.561; 95% CI: 0.254-0.830; p<0.001) and T1 proportion (coefficient, 0.207; 95% CI: 0.030-0.385; p=0.012) were significantly associated with the 3-year OS and CSS (coefficient for 3-year LC, 0.720; 95% CI: 0.468-0.972; p<0.001 and T1 proportion, 0.002; 95% CI: 0.000-0.003; p=0.012). Toxicities ≥grade 3 were low (3.4%).

CONCLUSIONS

Three-year LC was correlated with three-year OS in patients receiving radiotherapy for ES-NSCLC. A 5% increase in 3-year LC is expected to improve the 3-year CSS and OS rates by 3.8% and 2.8%, respectively.

Role of Stereotactic Radiation Therapy in Operable and Inoperable Early-Stage Non-small Cell Lung Cancer

OPINION STATEMENT

Radiation therapy is becoming an increasingly important part of non-small cell lung cancer (NSCLC) management. Approximately 60% of all cancer patients require radiation therapy (RT) as part of their treatment. For lung cancer, this number is even higher, reaching approximately 77% of all patients, from radical to palliative modalities of RT. This percentage may even be underestimated, as it may not account for the more recent use of RT in oligometastatic lung cancer patients. Thus, we can estimate that each year there will be approximately 21,890 new lung cancer patients in the USA requiring RT. These numbers are expected to continue to rise, as lung cancer radiation techniques continue to improve. There is growing interest in determining the best treatment options for early-stage NSCLC patients. There is well-established data showing the benefit of RT for inoperable patients, and more recent encouraging data even in operable patients.