[Prognosis in patients operated on for colorectal carcinoma: related to but not determined by number of lymph nodes examined].

The presence or absence of lymph node metastases is pivotal for the estimation of prognosis in carcinoma patients. The presence of lymph node metastases in patients with colorectal carcinoma (CRC) is an indicator of poor prognosis and adjuvant treatment is increasingly being given to these patients. For the patient much depends on effective staging of CRC. In patients with TNM stage II CRC, prognosis is related to the actual number of nodes harvested: those in whom fewer nodes are harvested fare less well. Understaging was suspected and therefore protocols now require a minimum number of nodes. Recent observational studies, however, have questioned understaging as a plausible mechanism. Tumour, biological or patient-related factors seem to be more likely. The number of nodes is not a suitable measure for the quality of pathological staging of CRC. Instead of this outcome measure, more attention should be paid to processes and future standards must be based on sound experimental evidence and not on observational surveys.