PURPOSE: After preoperative (radio)chemotherapy, histologic determinants for prognostication have changed. It is unclear which variables, including assessment of @entity5 regression, are the best indicators for local recurrence and survival. EXPERIMENTAL DESIGN: A series of 201 @entity1 with locally advanced @entity5 (cT3/T4, M0) presenting with an involved or at least threatened circumferential margin (CRM) on preoperative imaging (<2 mm) were evaluated using standard histopathologic variables and four different histologic regression systems. All @entity1 received neoadjuvant radiochemotherapy or radiotherapy. The prognostic value of all factors was tested with univariate survival analysis of time to local recurrence and overall survival. RESULTS: Local recurrence occurred in only 8% of the @entity1 with a free CRM compared with 43% in case of CRM involvement (P < 0.0001). None of the four regression systems were associated with prognosis, not even when corrected for CRM status. However, we did observe a higher degree of @entity5 regression after radiochemotherapy compared with radiotherapy (P < 0.001). Absence of @entity5 regression was associated with increasing invasion depth and a positive CRM (P = 0.02 and 0.03, respectively). CONCLUSIONS: Assessment of CRM involvement is the most important pathologic variable after radiochemotherapy. Although @entity5 regression increases the chance on a free CRM, in cases with positive resection margins prognosis is poor irrespective of the degree of therapy-induced regression.

Circumferential margin involvement is the crucial prognostic factor after multimodality treatment in XXXX with locally advanced rectal carcinoma.

@entity5 :: ('MESH:D009369', 'Disease') :: ['rectal cancer', 'tumor'] @entity1 :: ('9606', 'Species') :: ['patients']
@entity1 :: (9606,Species) :: ['patients']
