RESUMO
PURPOSE: Despite new treatment options in metastatic colorectal cancer (mCRC), new prognostic markers are still needed to determine optimal chemoregimen especially for anti-angiogenesis drugs. In this study, we evaluated the serum semaphorin and VEGF-A levels as prognostic factors in patients with mCRC. METHODS: Patients with diagnosed mCRC who were treated with first-line bevacizumab plus chemotherapy were included in the study. Venous blood samples of 37 patients with metastatic colon cancer were taken, and serum semaphorin 3A and VEGF-A levels were studied in pre-treatment and the 1st and third months after the treatment was initiated. RESULTS: Totally, 37 patients were enrolled in the study. The patients' mean age was 62 years. Twenty-eight (49%) of the patients were male, and 19 (51%) were female. Serum semaphorin3A (sema3A) levels of the patients were 5.4 ± 7.4 ng/ml before the treatment, 3.5 ± 3.3 ng/ml at the first month, and 3.5 ± 3.7 ng/ml at the third month. Serum VEGF-A levels were 27.7 ± 32.9 ng/l before the treatment, 23.1 ± 28.1 ng/l at the first month, and 28.9 ± 30.2 ng/l at the third month. There was no significant correlation between the survival and pre-treatment VEGF-A level (p = 0.064). Overall survival (OS) was statistically significantly higher in patients with pre-treatment semaphorin 3A levels below 5.4 ng/ml than higher than 5.4 ng/ml (10.5 months vs 4.5 months, respectively, HR 0.23, 95% CI 19.635-11,391, p = 0.012). CONCLUSION: Pre-treatment semaphorin 3A level can be a prognostic marker for the mCRC patients who were treated with bevacizumab in patients with metastatic colorectal cancer.
