Induction chemotherapy followed by concurrent chemoradiation (CRT) yields superior outcomes, when compared with CRT alone, in patients with nasopharyngeal carcinoma, according to a systematic review of phase 3 trials.
The trials showed improvements in disease-free survival (DFS), failure-free survival (FFS), relapse-free survival (RFS), and progression-free survival (PFS) with induction chemotherapy. However, there were conflicting results with regard to overall survival (OS).
These findings were published in Cancer Treatment and Research Communications.
The review included 6 phase 3 clinical trials in which patients were randomly assigned to receive induction chemotherapy plus CRT or CRT alone.
Induction chemotherapy was associated with superior 3-year RFS in 1 study (stratified hazard ratio [HR], 0.51; 95% CI, 0.34-0.77; P =.0001) and superior 3-year PFS in another study (HR, 0.44; 95% CI, 0.20-0.97; P =.042).
Two studies reported improvements in DFS with induction chemotherapy. The adjusted HR for 5-year DFS was 0.739 (95% CI, 0.565-0.965; P =.0264) in the first study. In the second study, the HR for 3-year DFS was 0.67 (95% CI, 0.47-0.95; P =.028), and the stratified HR for 5-year DFS was 0.66 (95% CI, 0.48-0.89; P =.007).
One study demonstrated an improvement in FFS with induction chemotherapy. The HR for 3-year FFS was 0.68 (95% CI, 0.48-0.97; P =.034), and the HR for 5-year FFS was 0.67 (95% CI, 0.48-0.94; P =.019).
OS was a secondary outcome in 5 of the 6 studies. Three of these studies showed a significant improvement in OS with induction chemotherapy, but 2 did not.
In the first study, induction chemotherapy was associated with a significant improvement in OS at 3 years (stratified HR, 0.43; 95% CI, 0.24 to 0.77). A second study showed an improvement in OS at a median follow-up of 6.9 years (HR, 0.69; 95% CI, 0.49-0.98, P =.040). The third study showed a significant improvement in OS at 3 years (HR, 0.59; 95% CI, 0.36-0.95; P =.029) and at 5 years (HR, 0.65; 95% CI, 0.43-0.98; P =.042).
The researchers noted that 1 of the 6 studies failed to meet its primary endpoint of improvement in OS. The authors of that study suggested that induction chemotherapy may not have been effective, or the reduction in the risk of death was smaller than the study was powered to detect.
Based on these findings, the researchers said they were unable to “make definite conclusions on the beneficial effect of IC [induction chemotherapy] in improving overall survival.”
The researchers noted that toxicities are a concern related to the use of induction chemotherapy in nasopharyngeal carcinoma, and all 6 trials in this review showed an increase in toxicity with induction chemotherapy.
Nazeer F, Poulose JV, Kainickal CT. Induction chemotherapy in nasopharyngeal carcinoma- A systematic review of phase III clinical trials. Cancer Treat Res Commun. Published online June 12, 2022. doi:10.1016/j.ctarc.2022.100589