Retrospective efficacy analysis of olaparib combined with bevacizumab in the treatment of advanced colorectal cancer

BACKGROUND: Colorectal cancer (CRC) is a highly prevalent malignancy of the digestive tract worldwide, characterized by a significant morbidity and mortality rate and subtle initial symptoms. Diarrhea, local abdominal pain, and hematochezia occur with the development of cancer, while systemic symptoms such as anemia and weight loss occur in patients with advanced CRC. Without timely interventions, the disease can have fatal consequences within a short span. The current therapeutic options for colon cancer include olaparib and bevacizumab, which are widely utilized. This study intends to evaluate the clinical efficacy of olaparib combined with bevacizumab in the treatment of advanced CRC, hoping to provide insights into advanced CRC treatment. AIM: To investigate the retrospective efficacy of olaparib combined with bevacizumab in the treatment of advanced CRC. METHODS: A retrospective analysis was conducted on a cohort of 82 patients with advanced colon cancer who were admitted to the First Affiliated Hospital of the University of South China between January 2018 and October 2019. Among them, 43 patients subjected to the classical FOLFOX chemotherapy regimen were selected as the control group, and 39 patients undergoing treatment with olaparib combined with bevacizumab were selected as the observation group. Subsequent to different treatment regimens, the short-term efficacy, time to progression (TTP), and incidence rate of adverse reactions between the two groups were compared. Changes in serum-related indicators [vascular endothelial growth factor (VEGF), matrix metalloprotein-9 (MMP-9), cyclooxygenase-2 (COX-2)] and tumor markers [human epididymis protein 4 (HE4), carbohydrate antigen 125 (CA125), carbohydrate antigen 199 (CA199)] levels before and after treatment were compared between the two groups at the same time. RESULTS: The objective response rate was discovered to be 82.05%, and the disease control rate was 97.44% in the observation group, which were significantly higher than the respective rates of 58.14% and 83.72% in the control group (P < 0.05). The median TTP was 24 mo (95%CI: 19.987-28.005) in the control group and 37 mo (95%CI: 30.854-43.870) in the observation group. The TTP in the observation group was significantly better than that in the control group, and the difference held statistical significance (log-rank test value = 5.009, P = 0.025). Before treatment, no substantial difference was detected in serum VEGF, MMP-9, and COX-2 levels and tumor markers HE4, CA125, and CA199 levels between the two groups (P > 0.05). Following treatment with different regimens, the above indicators in the two groups were remarkably promoted (P < 0.05), VEGF, MMP-9, and COX-2 in the observation group were lower than those in the control group (P < 0.05), and HE4, CA125, and CA199 levels were also lower than those in the control group (P < 0.05). Vis-à-vis the control group, the total incidence of gastrointestinal reactions, thrombosis, bone marrow suppression, liver and kidney function injury, and other adverse reactions in the observation group was notably lowered, with the difference considered statistically significant (P < 0.05). CONCLUSION: Olaparib combined with bevacizumab in the treatment of advanced CRC demonstrates a strong clinical effect of delaying disease progression and reducing the serum levels of VEGF, MMP-9, COX-2 and tumor markers HE4, CA125 and CA199. Moreover, given its fewer adverse reactions, it can be regarded as a safe and reliable treatment option.