ACR Appropriateness Criteria: local excision in early-stage rectal cancer

Low anterior resection or abdominoperineal resection is considered standard treatment for early rectal cancer. These procedures, however, carry a risk of morbidity and mortality that may not be warranted for early distal lesions, which may be treated with local excision. Emerging data has investigated the efficacy of local excision in patients with early stage rectal cancers. An expert panel designated by the American College of Radiology has reviewed supporting data, from a few prospective multi-institutional trials and a number of single-institution, retrospective reviews. The consensus recognizes the importance of accurate staging to identify patients who may be candidates for a local excision approach. Optimal candidates for local excision alone include small, low-lying T1 tumors, without adverse pathologic features. A number of procedures may be safely used including transanal, posterior trans-sphincteric, posterior proctotomy, transanal excision, or transanal microsurgery. It is important to note that none of these include lymph node evaluation, and depending on the risk of lymph node metastases, adjuvant radiation with or without chemotherapy may be warranted. Patients with positive margins or T3 lesions are at high risk of local recurrence and should be offered immediate APR or LAR. However, patients with high-risk T1 tumors, T2 tumors, or those who are not amenable to more radical surgery may benefit from adjuvant treatment. Data have also reported excellent local control rates for neoadjuvant radiation +/- chemotherapy followed by local excision in higher risk patients, but it is not yet clear if this approach reduces recurrence rates over surgery alone.