PPIs safe to use with capecitabine-based NACRT for locally advanced rectal cancer

Concomitant use of proton pump inhibitors (PPIs) with capecitabine-based neoadjuvant chemoradiotherapy (NACRT) for locally advanced rectal cancer (LARC) is safe and does not result in any adverse pathologic or oncological outcome, reports a study.

“Capecitabine is routinely used for the NACRT of LARCs,” the investigators said. “Previous reports have suggested that the concomitant use of PPIs may affect the efficacy of capecitabine, although the true effect of PPIs when used with capecitabine as a radiosensitizer for neoadjuvant radiation is unclear.”

This study then evaluated the impact of concurrent PPI use along with fluorouracil (FU) and capecitabine-based NACRT in terms of pathologic and oncological outcomes in patients with LARC who received such treatment from 2010 to 2016. The investigators assessed postoperative pathology and follow-up outcomes for any differences with relation to the use of PPIs concurrently with FU and capecitabine-based NACRT and adjuvant chemotherapy regimens.

Overall, 304 and 204 patients received treatment with FU and capecitabine-based NACRT. The pathologic complete response rate did not differ between the two groups with the concurrent use of PPIs (25.8 percent and 25.0 percent, respectively; p=0.633), or with and without the use of PPIs in the capecitabine-based NACRT arm specifically (20.0 percent and 20.7 percent; p=0.945).

No statistical difference was observed in local or distant control in the capecitabine-based NACRT group, with (p=0.411) and without (p=0.256) concomitant PPI use, at a median follow-up of 5 years. In multivariate analysis, concurrent PPI and NACRT with capecitabine showed no association in terms of local control (hazard ratio, 0.001; p=0.988) and overall survival (hazard ratio, 1.179, 95 percent confidence interval, 0.249–5.579; p=0.835).

“We report that it may be safe to use PPIs if essential, in this clinical setting, although it would be wise to exercise caution,” the investigators said.