Predictors of Survival in Stage IV Metastatic Colorectal Cancer

The aim of this study was to evaluate predictors of survival in stage IV metastatic colorectal cancer (CRC). Patients and Methods: A total of 541 patients with histologically proven metastatic CRC (UICC stage IV) were retrospectively analysed and 37 variables were tested for their potential relationship to survival. Results: Mean survival time was recorded at 12.8 months (95% confidence interval (CI) 12.0- 13.5). Three factors were independently associated with improved survival: combination chemotherapy, improved performance status and dermatological complications. Eight factors were independently associated with unfavorable survival: worsened performance status, C-reactive protein >5 mg/dl, anemia, anorexia, weight loss ≥10%, fatigue, hypoalbuminemia and blood transfusions. Conclusion: A number of factors could be used as predictors of survival in patients with stage IV metastatic CRC. Patients who are relatively fit, have low CRP levels and tolerate combination chemotherapy appear to have a more favorable survival outcome. Approximately 35% of colorectal cancer (CRC) patients present with stage IV metastatic disease at the time of diagnosis and 20%-50% with stage Ⅱ or Ⅲ disease will progress to stage Ⅳ at some point during the course of their disease (1-3). Stage IV CRC carries a dismal prognosis: the 5-year survival rate for stage IV CRC is less than 10% (2, 3) and the median survival time of patients with stage IV CRC given optimal supportive care without chemotherapy is approximately 5 months (4). In metastatic CRC, chemotherapy is used mainly with palliative intent. It improves quality of life and prolongs survival in comparison with best supportive care alone (4). Until a few years ago, 5-fluorouracil (5-FU) modulated with folinic acid was the reference first-line treatment option for metastatic CRC, with objective response rates of 10-25% and managable toxicity (5). Treatment options for patients with metastatic CRC are continuously evolving, with the development of new chemotherapeutic agents. With three classes of cytotoxic agents and two classes of therapeutic antibodies currently available, treatment decision-making is more complicated as the optimum sequencing and dosing of cytotoxic and biological agents remains to be determined. Nevertheless, during the past decade, the application of these new chemotherapeutic agents in the treatment of metastatic CRC has increased, with concomitant improvement in outcome (6, 7). However, as treatment with these new agents is associated with significant toxicity, there is a need to identify prognostic factors which may determine treatment response and survival. Such an approach could refine management with palliative chemotherapy according to the likelihood of clinical benefit (8). The aim of this study was to evaluate predictors of survival in stage IV metastatic CRC.