Multiple treatment lines and prognosis in metastatic colorectal cancer patients

The proportion of patients with metastatic colorectal cancer (mCRC) receiving second or further lines of treatment has not been widely studied. To shed light on this issue, we retrospectively analysed the treatments administered for metastatic disease, and investigated prognostic factors after a diagnosis of metastases, in a consecutive cohort of mCRC patients. Three hundred forty-six mCRC patients were enrolled: 173 were stage II or III (metachronous group), and 173 stage IV (synchronous group) at diagnosis. Survival was calculated between the date of metastatic disease and the date of death or last follow-up. Patients with synchronous lesions more frequently had multiple disease sites, peritoneal carcinomatosis and massive liver deposits, whereas significantly more patients with metachronous lesions developed lung metastases as the sole disease site. 97.4% patients received at least one, 62.4% two, 41.9% three and 23.7% four treatment lines. Patients with metachronous metastases more frequently underwent surgery of metastases in first-line treatment (48.5 versus 24.8%), and more of them were progression-free at the time of the analysis (44 versus 34.9%). At univariate analysis, age > 70 years, multiple disease sites and peritoneal carcinomatosis were associated with significantly decreased survival, whereas surgery of metastases and isolated lung metastases predicted better survival. At multivariate analysis, only peritoneal carcinomatosis and surgery of metastases independently affected survival. The percentage of patients who received an active treatment decreased going from first- to fourth-line treatment. However, the proportion of patients who received efficacious treatment in advanced line remained high. Surgery of metastases was the most important prognostic factors.