Preoperative Assessment of Mesorectal Lymph Nodes by Dual Energy CT. PUMK-DECT

Background Long-term survival for patients with cancer of the rectum (RC) is through the last 20 years dramatically improved from about 30% to 65% . Overall focus on disease with the creation of multidisciplinary teams, national quality databases certification of surgeons, etc. have contributed to the development especially in the last 10-15 years . The introduction of pre-operative Oncology, known as neoadjuvant treatment increased the survival rate by up to 10% in certain patient series. However, the prognosis remains poor for advanced cases, qua risk of metastasis and local cancer relapse.

Surgical treatment remains the cornerstone of curative treatment of RC. Total mesorectal excision (TME) includes resection of both the tumor and the surrounding mesorectal fat. TME is currently used as the gold standard for surgical treatment of RC. The use of TME has reduced local relapse rate to less than 10%.

TME surgery combined with preoperative chemotherapy and radiation therapy if the cancer is in an advanced stage (T3), and often with high-dose radiotherapy and chemotherapy in the most advanced cases of T-stage 4.

Complications of TME are present in more than 40% of patients. Most often in the form of wound dehiscence, infection, sexual dysfunction, bowel disorders and the necessity of a stoma. More than 50% of patients have permanently reduced quality of life.

Minimally invasive therapies (trans-anal endoscopic microsurgery (TEM)) for the curative treatment of early rectal cancers, is well-validated. The complication rate is low, and above all, the operative mortality of less than 1% even in the elderly and patients with comorbidities, opposed to 10% at standard surgery. The use of TEM surgery early in the rectum cancers in selected patients will thus be able to reduce the risk of complications and improve the overall long-term survival. Even though the disease-specific survival is reduced due to a less radical procedure. The Danish screening program for colorectal cancer will result in a significant increase in the detection of early cancers.