Colorectal cancer (CRC) is one of the leading causes of cancer death in Europe. In this issue of Gut, Gatta and colleagues1 report survival results from a population based study involving 2270 cases of CRC from 11 cancer registries in six European countries (see page 533). The authors report a surprisingly wide range of overall survival among the registries; three year survival varied from a low of 25% in Cracow, Poland to a high of 59% in Modena, Italy. An understanding of the causes for this wide variation could serve as the database for efforts to improve the overall outcome of CRC.

It is well established that the prognosis of CRC is dependent on factors related to the tumour, the patient, and the treatment of the disease. More advanced stage, location of the cancer in the rectum, poorly differentiated histology, vascular invasion, and older age are all associated with a poorer prognosis of CRC.2 The surgical approach (extent of resection, electivev emergency, skill of the surgeon) and appropriate use of adjuvant therapy also significantly affect overall survival.2 ,3 Much of the variation between registries in the report by Gatta and colleagues1 appears to be due to differences in known prognostic factors. Not surprisingly, the four registries that reported the poorest overall survival also had the four lowest reported percentages of early stage disease and had four of the five highest rates of rectal cancer. After adjustment for these factors, however, …