Staging and treatment of early rectal cancer

Accurate preoperative staging of early rectal cancers is necessary in order to select those patients who will benefit from local resection or non-surgical treatment. Staging should combine inspection, digital examination, biopsy and transanal endoluminal ultrasonography. The patients' age and physical performance may also influence the decision. Major surgery for early rectal cancer is followed by a long term cancer-specific survival of more than 90%. The overall mortality is largely due to the surgical trauma or causes other than the cancer disease. Some patients with high age or co-morbidity and rectal cancers of T stage 1 and 2, sometimes even 3 can be offered local resection without compromising long term survival. The low risk T1 cancers can safely be treated with transanal endoscopic microsurgery. The long term results match those of major surgery. The long term results for high risk early cancers treated with radiotherapy and transanal endoscopic microsurgery may match those of major surgery, but prospective randomized trials are needed for a firm conclusion. Local resection of high risk, early rectal cancers should be reserved for those with high age or co-morbidity or it should be combined with preoperative radiotherapy. In cases of possible oncological compromise, the patient should decide how to prioritize short and long term survival, risk of complications and quality of life. The patient and the surgeon should be prepared for early rescue surgery after transanal surgery in case of staging errors. The oncological safety of colonoscopic submucosal dissection is not clear and transanal endoscopic microsurgery is currently recommended for local resection of early rectal cancers. Non-surgical treatment of early rectal cancers has gained renewed interest. The rate of complete oncological response is increasing as external radiotherapy is combined with modern chemotherapy and possible endocavitary radiotherapy. Combined oncological treatment induces a complete pathological response in 30% or more of the early cancers. The frequency of early rectal cancers is low in areas without population screening programmes and the decision and planning of the treatment should be handled by a multidisciplinary team of dedicated specialists.