Effect on survival of PPI use with capecitabin in patientswith breast cancer and colorectal cancer

Aim: Breast cancer and colorectal cancer are among the most common cancers worldwide. In the treatment of patients with colorectal cancer and breast cancer, capecitabine- containing treatment regimens cover an especially important part. Since capecitabine is taken orally, it may interact with other drugs when used simultaneously. Limited studies have shown that concomitant use of ppi with capecitabine reduces survival. Studies have focused on colon cancer, and studies in this area are limited. In this study, we aimed to examine the negative effect of simultaneous ppi use of capecitabine on survival in patients with colon cancer and metastatic breast cancer. Materials and methods: Between January 2015 and December 2020, 66 patients with neoadjuvant-adjuvant colon cancer, 40 metastatic colon cancer and 60 metastatic breast cancer patients who were followed up and treated in Meram Medical Faculty Oncology Clinic were evaluated retrospectively according to demographic characteristics and ppi use. Results: A total of 166 patients, 66 of whom had adjuvant-neoadjuvant colon cancer, 60 metastatic breast cancer, 40 metastatic colon cancer, were included in this study. Of the patients with metastatic colon cancer, 62.50% (n=25) were male and 37.50% (n=15) were female. While half of the patients in this group were using ppi, half were not using ppi. In the group of patients with metastatic colon cancer, the mean survival time of patients using PPI was 39,47 (CI: 30.06-48.87) months, and patients not using PPI were 44,29 (CI: 33.77- 54,81) months. The effect of PPI use on survival was not statistically significant (p=0.39) viii The mean progression-free survival time of patients using PPI in the group of patients with metastatic colon cancer was 15,92 (CI: 9,73-22,12) months, and 21.88 (CI: 12.39-31.36) months in patients not using PPI . The effect of PPI use on progression-free survival was not statistically significant (p=0.80) Of the patients with adjuvant-neoadjuvant colon cancer, 63.60% (n=42) were male and 36.40% (n=24) were female. In this group, 26 people were using ppi, while 40 people were not using ppi. In the adjuvant-neoadjuvant colon cancer patients group, the mean survival time of patients using PPI was 84,44 (CI: 62.64-106,24) months, and patients not using PPI were 78,58 (CI: 70.37-86.78) months. The effect of PPI use on survival was not statistically significant (p=0.85) All patients with metastatic breast cancer were women. While 33 people used ppi, there were 27 people who did not use ppi. In the breast cancer patient group, the mean survival time of patients using PPI was 105,21 (CI: 77.37-133,05) months, and 139,13 (CI: 100,86-177,39) months in patients not using PPI. The effect of PPI use on survival in breast cancer patients was not statistically significant (p=0.12). The mean progression-free survival time of patients using PPI in breast cancer group was 19,53 (CI: 12,99-26.06) months, and patients not using PPI were 36,91 (CI: 21,44-52.39) months. determined. The effect of PPI use on progression-free survival was not statistically significant (p=0.34) Conclusion: In our study, concomitant use of capecitabine and ppi did not have a significant negative effect on progression-free survival and mean overall survival in patients with colon and breast cancer. The most important limiting factor in this study is the small number of patients. Keywords: colorectal cancer, breast cancer, ppi, capecitabine, survival