Should radiotherapy be given at the same time or after chemotherapy for patients with advanced non-small cell lung cancer?

This study investigated the effectiveness and safety outcomes of radiotherapy given at the same time (concurrent chemoradiotherapy; cCRT) or after chemotherapy (sequential chemoradiotherapy; sCRT) for the treatment of patients with advanced non-small-cell lung cancer (NSCLC). The data showed that cCRT improved the long-term outcomes of these patients while increasing the side effects.

Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. NSCLC is responsible for around 85% of all lung cancer diagnoses. Standard treatment for advanced NSCLC involves surgical removal of solid tumors and chemoradiotherapy (CRT). CRT involves administering both chemotherapy (CT) and performing radiation therapy (RT). There are two strategies for delivering CRT in NSCLC.

The first strategy is called concurrent CRT (cCRT). This involves administering both CT and RT during the same treatment period. The second approach is called sequential CRT (sCRT). This involves first administering CT. Once completed, RT is performed. This can also meant giving RT first followed by CT. sCRT may be better tolerated than cCRT. However, there are few studies investigating the effectiveness and safety outcomes of cCRT compared with sCRT for advanced NSCLC.

This study analyzed 14 studies that involved 2634 patients with NSCLC. Patients had either cCRT or sCRT. The average follow-up time ranged from 1.3 years to 11 years.

After 1 year, there was no difference in survival between sCRT and cCRT. However, after 2 years, cCRT significantly increased the survival rates by 25% compared to sCRT. After 3 years, cCRT was associated with a 38% higher chance of survival compared to sCRT. Also, after 4 years, there was a 56% higher chance of survival with cCRT compared to sCRT. After 5 years, the chance of survival with cCRT was 49% higher compared to sCRT. 

Patients who received cCRT were 20% less likely to experience locoregional relapse (reappearance of the cancer in and around the original site of disease) compared to those who received sCRT. cCRT significantly increased the overall response to treatment by 13% compared to sCRT.

Significantly more severe side effects were associated with cCRT compared to sCRT. The most common side effects were inflammation of the esophagus lining, nausea/vomiting, and a low number of white blood cells and platelets.

This study concluded that cCRT significantly improved the outcomes of patients with advanced NSCLC. However, cCRT increased the risk of side effects in these patients.

The studies analyzed had very different protocols. Different types of CRT strategies were performed in the studies which could affect the conclusions.