Outcomes of Prophylactic Cranial Radiotherapy in Small-Cell Lung Cancer: A Retrospective Analysis

Objective: In this study, a retrospective trial was done to determine the rate of development of brain metastasis in small-cell lung cancer patients treated with concomitant chemoradiotherapy or after chemotherapy chest radiotherapy and then prophylactic cranial radiotherapy and to evaluate the overall survival of the patients and compare it with literature data.

Methods: In this study, patients who were diagnosed with small-cell lung cancer between 2014 and 2022, who received concomitant chemoradiotherapy or thoracic radiotherapy after chemotherapy, whose disease was stable or in remission, without brain metastases, who did not receive cranial radiotherapy before, and who received 25 Gy (2.5 Gy/10) fraction undergoing prophylactic cranial radiotherapy were included. A total of 87 patients were included in this study.

Results: Of the 87 patients, 9 (10%) patients were female and 78 (90%) were male, with a mean age of 62.17 ± 8.33 (range: 41-80) years. The median follow-up was 23 months (range: 5–82 months). Brain metastases developed in 21 (24%) of the patients. The time between thoracic radiotherapy and prophylactic cranial radiotherapy in these patients was 1.92 ± 1.89 (range: 0-7) months. The time between prophylactic cranial radiotherapy and brain metastasis was 8.64 ± 7.3 (range: 2–30) months. The mean overall survival time of all patients was 33.47 ± 5.06 months (confidence interval, 23.66-43.28), and the median overall survival was 18 ± 2.67 (95% confidence interval, 12.74-23.25) months. The 1-, 2-, 3-, and 5-year overall survival rates were 84.7%, 49.2%, 36.3%, and 12.5%, respectively.

Conclusion: Prophylactic cranial radiotherapy is now used to treat both limited and extensive-stage small-cell lung cancer that responds to initial therapy. With combined therapy, the risk of thoracic recurrence is reduced, and as a result, brain metastases become one of the main types of recurrence. Our study demonstrates that prophylactic cranial radiotherapy is a low-risk, safe treatment option for small-cell lung cancer patients to avoid brain metastases. However, additional long-term, large-scale studies are needed to back up these findings and draw firm conclusions.

Cite this article as: Kandaz M, Tüysüz A, Aydoğdu K, Şahin M, Balsak A, Mammadov E. Outcomes of prophylactic cranial radiotherapy in small-cell lung cancer: A retrospective analysis. Arch Basic Clin Res., 2023;5(3):355-363.