Background: Colorectal cancer (CRC) is a major cause of mortality in developed countries, and it is the thirdmost frequent malignancy in Turkey. There are many biological, genetic, molecular, and tissue-derived prognosticfactors for CRCs. In this study, we evaluated prognostic factors in patients who were metastatic at diagnosis orprogressed to metastatic disease during follow-up. Patients and
Methods: This study included 116 patients withmalignancies either in the colon or rectum. Of these, 65 had metastatic disease at diagnosis, and 51 progressedto metastatic disease during the course of the disease. The parameters evaluated were age, gender, comorbidity,performance status and stage of the disease at the beginning, localization, history of surgery, chemotherapyregimen, response to first-line treatment, K-RAS status, site and number of metastases, expression of tumorpredictors (CEA, CA19-9), and survival times. A multivariate analysis conducted with factors that consideredstatistically significant in the univariate analysis. Findings: Median age was 56 (32-82) years and the male/female ratio was 80/36. Eleven patients were at stage II, 40 at stage III, and 65 at stage IV at diagnosis. Twentythree patients had tumor in the right colon, 48 in the left colon, and 45 in the rectum. Ninety seven patients wereoperated, and 27 had surgical metastasectomy. Ninety three patients received targeted therapy. At the end offollow-up, 61 patients had died, and 55 survived. Metastatic period survival times were longer in the adjuvantgroup, but the difference did not reach the level of statistical significance (adjuvant group: median 29 months,metastatic group: median 22 months; p=0.285). In the adjuvant group before the metastatic first-line therapy,CEA and CA 19-9 levels were significiantly lower compared to the metastatic group (p<0.005). We also foundthat patients with elevated tumor predictor (CEA, CA 19-9) levels before the first-line therapy had significiantlypoorer prognosis and shorter survival time. Survival was significiantly better with the patients who were youngerthan 65 years of age, had better initial performance status, a history of primary surgery and metastatectomy,and single site of metastasis. Those who benefitted from the first-line therapy were K-RAS wild type and whosetumor markers (CEA, CA 19-9) were not elevated before the first line therapy.
Conclusions: Among the patientswith metastatic CRC, those who benefited from first-line therapy, had history of metastasectomy, were K-RASwild type and had low CA 19-9 levels before the first-line therapy, showed better prognosis independent of otherfactors.