total mesorectal excision the rectum and its mesentery are a single fascia-enveloped unit, anatomically separate from surrounding pelvic structures surgical violation of this anatomic package leads to a positive circumferential margin, a known predictor of local recurrence
German rectal cancer study 823 patients - Stage II-III 50.4 Gy RT + Chemo OR (TME) 50.4 Gy RT + Chemo OR (TME) Sauer 2003
German rectal cancer study Sauer, NEJM 2005 Pre-OpPost-Op Leak 10% 12% Bleed 2% 3% Delayed healing 4% 6% Stricture 4% 12%* Acute toxicity 27% 40%*
Downstaging8% Sphincter Preservation39%19%* Local Recurrence6%13%* Survival76%74% German rectal cancer study Sauer, NEJM 2005 Pre-OpPost-Op * p<0.05
short vs. long course United States: Europe: 45-54 Gy 6 weeks OR OR 1 week 25 Gy
short course radiation convenience cost effectiveness unsafe if given improperly ? higher rate of late toxic effects cannot give simultaneously with chemotherapy procon
short course vs. conventional radiation no data!
radiation therapy current status (USA) optimally stage patient (ERUS) conventional (long course) RT plus chemotherapy for stage II (T3), stage III (N1) or stage IV cancers postoperative chemoradiation for positive circumferential margin consider postoperative chemoradiation for understaged T3 or N1 lesions
RECTAL CANCER AS BREAST CANCER: PARADIGM FOUND?
RECTAL CANCER LOCAL EXCISION pro –low morbidity/mortality –avoids sexual/urinary/bowel dysfunction –avoids colostomy con –nodal status not pathologically assessed –involved nodes not excised –? equivalent oncologic results to radical excision
It is the wise surgeon who understands that the patient takes all the risk.
local excision rules of engagement selection, selection, selection! –ERUS stage first, but reassess pathologic specimen –no “winking” at adverse histology or inadequate margins adjuvant chemoradiation for pT2 tumors mandate close follow up remember that recurrent tumors are almost always more advanced than they start, and radical salvage surgery cures only 50% of patients
local excision preoperative chemoradiation? downstages tumor –? curative in some patients may reduce risk of tumor implantation at excision site
rectal cancer therapy morbidity mortality function optimal cure rate
rectal cancer conclusions numerous treatment permutations appropriate treatment depends upon tumor stage, which should be determined before surgery surgery is technically driven; optimal results require training and experience role of local therapy remains controversial oncologic cure is the primary goal, but functional results are an important outcome