PURPOSE: An important feature of @entity5 is the disturbance in the balance between proliferation and cell death. We evaluated the relevance of intrinsic and radiation-induced apoptosis and proliferation for prognosis in @entity5 @entity1 . METHODS AND MATERIALS: @entity1 were selected from a study that randomized for preoperative radiotherapy (RT). Apoptosis and proliferation were scored using specific antibodies in immunohistochemistry. The number of positive cells per square millimeter of @entity189 cells was determined in 98 randomly selected @entity5 , of which 45 had been irradiated. For the survival analyses, a cohort of 104 @entity1 without positive circumferential resection margins was selected. RESULTS: In nonirradiated @entity1 , high levels of intrinsic apoptosis correlated with better local control (p = 0.04) and better @entity5 -specific survival (p = 0.02). RT increased the median amount of apoptosis from 10.8 to 21.5 cells/mm(2) (p = 0.004), but this was not predictive for survival. The amount of proliferative cells was not altered after RT and had no influence on prognosis. CONCLUSIONS: Intrinsic apoptosis correlated with both local control and @entity5 -specific survival, but proliferation was not predictive for prognosis. However, although RT increased apoptosis, its prognostic value was lost after RT. This is possibly because in @entity5 , the proliferative status of @entity5 is always high and the @entity146 of the @entity5 is determined by the number of "spontaneous" apoptotic @entity5 cells.

High intrinsic apoptosis, but not radiation-induced apoptosis, predicts better survival in @entity189 XXXX .

@entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'malignant tumors', 'cancer', 'rectal cancer', 'tumors'] @entity1 :: ('9606', 'Species') :: ['Patients', 'patients'] @entity189 :: ('MESH:D002277', 'Disease') :: ['carcinoma'] @entity146 :: ('MESH:D001523', 'Disease') :: ['aggressiveness']
@entity1 :: (9606,Species) :: ['patients']
