Importance of tumor regression assessment in predicting the outcome in patients with locally advanced rectal carcinoma who are treated with preoperative radiotherapy

摘要: BACKGROUND Locally advanced rectal carcinoma has a poor prognosis. However, since the introduction of preoperative radiotherapy, outcome patients with been reported to have improved. Nevertheless, authors' knowledge few data are available regarding histopathologic response radiotherapy as assessed on surgical specimens potential predictive factor for outcome. METHODS To estimate effect carcinoma, authors retrospectively reviewed 102 T3-4, N0 or ≥ N1 and 1 patient T2 but carcinoma. All were treated preoperatively hyperfractionated accelerated schedule in prospective protocol (Trial 93-01). Using standardized approach, tumor regression was graded using system that varies from Grade (tumor [TRG] 1) when complete is observed 5 (TRG5) no observed. RESULTS Radiotherapy resulted downstaging 43% patients. There 2 pT1 tumors (2%), 21 pT2 (20%), 66 pT3 (64%), 14 pT4 (14%) after treatment. Regional lymph nodes involved 55 (53%). None demonstrated 79% partial (TRG1: 0%; TRG2: 20%; TRG3: 39%; TRG4: TRG5: 21%). The median actuarial overall survival (OS) disease-free (DFS) 52 months. Actuarial local recurrence rates at years 6.4% 7.6%, respectively. Univariate analysis showed DFS be significantly lower node metastases (P = 0.0004) pT stages (pT3-4) 0.03). A favorable OS, DFS, control TRG2-4 (i.e., responders) compared TRG5 nonresponders), also low residual cell density (TRG2, 3, 4). On multivariate analysis, TRG remained an independent prognostic indicator control. CONCLUSIONS Tumor well found factors radiotherapy. Even pathologic stage specimen factor. use approach evaluation must implemented allow comparison between results various treatment approaches.