2006 - UZ Leuven

data we propose a scoring system in order to base the decision forsurgery on more objective grounds and weighted criteria. The RiskScore is based on 4 risk factors: male sex, patients younger than 45years, diverticula longer than 2 cm and the presence of a fibrousband. We suggest resection of an asymptomatic MD with a Risk Score≥ 6 points. A transverse diverticulectomy is preferable in most cases.In short, broad MD, or in the case of a palpable mass at the base, awedge-shaped excision is the best alternative.ROELS S., DUTHOY W., HAUSTERMANS K., PENNINCKX F.,VANDECAVEYE V., BOTERBERG T., DE NEVE W.: Definition anddelineation of the clinical target volume for rectal cancer. Int. J.Radiation Oncology Biol. Phys., 2006; 65(4): 1129-1142.Purpose: Optimization of radiation techniques to maximize local tumorcontrol and to minimize small bowel toxicity in locally advanced rectalcancer requires proper definition and delineation guidelines for theclinical target volume (CTV). The purpose of this investigation was toanalyze reported data on the predominant locations and frequency oflocal recurrences and lymph node involvement in rectal cancer, topropose a definition of the CTV for rectal cancer and guidelines for itsdelineation.Methods and Materials: Seven reports were analyzed to assess theincidence and predominant location of local recurrences in rectalcancer. The distribution of lymphatic spread was analyzed in another10 reports to record the relative frequency and location of metastaticlymph nodes in rectal cancer, according to the stage and level of theprimary tumor.Results: The mesorectal, posterior, and inferior pelvic subsites aremost at risk for local recurrences, whereas lymphatic tumor spreadoccurs mainly in three directions: upward into the inferior mesentericnodes; lateral into the internal iliac lymph nodes; and, in a few cases,downward into the external iliac and inguinal lymph nodes. The risk forrecurrence or lymph node involvement is related to the stage and thelevel of the primary lesion.Conclusion: Based on a review of articles reporting on the incidenceand predominant location of local recurrences and the distribution oflymphatic spread in rectal cancer, we defined guidelines for CTVdelineation including the pelvic subsites and lymph node groups atrisk for microscopic involvement. We propose to include the primarytumor, the mesorectal subsite, and the posterior pelvic subsite in theCTV in all patients. Moreover, the lateral lymph nodes are at high riskfor microscopic involvement and should also be added in the CTV.10