Can Chest Wall Radiotherapy Benefit Small Cell Lung Cancer?

A study presented at the American Society for Radiation Oncology's annual meeting found that adding chest wall radiotherapy to chemotherapy and prophylactic brain radiotherapy in advanced small cell lung cancer benefited both disease course and survival.

Lung cancers are divided into 2 main groups according to how the cells appear under the microscope: small cell lung cancer and non-small cell lung cancer. Non-small cell lung cancers are more common and have a more favorable course, whereas small cell lung cancers are less common but progress much faster and more aggressively. The disease has often already spread to other organs when diagnosed, and further spread (metastasis) during treatment is possible. This is also the type of lung cancer most strongly associated with smoking and is very rare in nonsmokers.

Chemotherapy is the main treatment for small cell lung cancer. Surgery is usually not possible because the disease has generally spread by diagnosis and progresses aggressively, although it may rarely be used for small tumors. Because this cancer frequently spreads to the brain, preventive brain radiotherapy (prophylactic cranial irradiation) is also given. However, controlling the tumor in the lungs remains the greatest problem. Although adding chest wall radiotherapy to chemotherapy is thought to help control this tumor, the evidence from studies has been insufficient to recommend the approach definitively. A recently published study therefore examined how chest wall radiotherapy affects disease progression and overall survival in these patients.

The study, presented at the American Society for Radiation Oncology's annual meeting, included 498 patients with advanced (disseminated) small cell lung cancer that had responded to chemotherapy. Some received chemotherapy, prophylactic brain radiotherapy and chest wall radiotherapy, while the other group received only chemotherapy and prophylactic brain radiotherapy. The groups were followed for approximately 24 months. Analysis showed a significantly higher 2-year survival rate in the chest wall radiotherapy group (13% versus 3%). Disease control for 6 months (6-month progression-free survival) was also more frequent among patients receiving chest wall radiotherapy (24% versus 3%).

In conclusion, this study indicates that adding chest wall radiotherapy to chemotherapy and prophylactic brain radiotherapy in advanced (disseminated) small cell lung cancer benefits both disease course and survival. The most appropriate next step is to support this treatment strategy with further studies and incorporate it into clinical practice after considering other factors as well.