Identifying which patients with ES-SCLC would benefit from radiation

This trial looked at factors which would help predict whether aggressive radiation would be beneficial to patients with extensive stage small cell lung cancer who have progressed passed chemotherapy. The authors concluded that patients with less than three metastases (spread of cancer) would benefit most.

Extensive-stage small cell lung cancer (ES-SCLC) is an aggressive cancer usually treated with chemotherapy. However, the cancer usually persists, reoccurs in the lung or spreads to other areas of the body after chemotherapy. One trial examined treating patients with radiation to the lung (TRT) after the cancer progressed passed chemotherapy. Initial results showed that this reduced the risk of recurrence in the lung from 80% to 44%. There were low levels of side effects in this trial and therefore a higher dose of radiation might be more effective. It is therefore important to identify patients who could benefit from a higher dose of radiation.

This trial aimed to identify factors that would help predict whether a patient was more likely to benefit from high dose TRT. The trial included 260 patients with ES-SCLC who had progressive disease after chemotherapy.

Patients with bone metastases treated with TRT had a 60% longer progression-free survival (PFS, time from treatment until disease progression) than those not treated with TRT. There was no difference for patients who had liver metastases. Patients without liver metastases who were treated with TRT had 74% longer PFS than those who were not.  

Patients with less than 2 metastases who were treated with TRT had 2-fold better PFS and had better overall survival (time from treatment until death from any cause) than those who were not treated with TRT. Patients with more than 2 metastases who were treated with TRT had 25% better PFS.

Overall, factors which predicted better PFS were treatment with TRT and no bone metastases.

The authors concluded that the patients who would benefit the most from aggressive TRT are those with fewer than 3 metastases.