Short-term preoperative radiotherapy interferes with the determination of pathological parameters in XXXX .

@entity5 @entity1 @entity189
Short-term preoperative radiotherapy in combination with surgery has been shown to decrease the rate of local recurrence in @entity5 @entity1 . The effects of this type of radiotherapy on the histopathology of @entity189 has been hitherto unknown. Since various histopathological factors are associated with prognosis, the study of alterations induced by irradiation is an important issue. This paper examines the histopathology of resection specimens from 1306 @entity1 who were treated in a randomized trial that evaluated the benefits of preoperative radiotherapy. In this trial, @entity1 were treated with short-term radiotherapy (5 x 5 Gy) and operated on within 5 days after radiation. Histopathological parameters were determined by the Pathology Review Committee of the trial and we compared @entity5 of @entity1 with and without preoperative radiotherapy. Tumours of @entity1 who were treated with preoperative radiotherapy were smaller, more @entity189 (13% versus 7%, p < 0.001) and more often poorly differentiated (35% versus 24%, p<0.001). After radiotherapy, there was less inflammatory reaction around the @entity5 (extensive in 7% versus 18%, p<0.001), which was mainly caused by a decrease in T lymphocytes and neutrophil granulocytes. The fibroblastic reaction was more pronounced in the radiotherapy group (extensive in 22% versus 10%, p <0.001). Remarkable histological alterations occurred within a week after 5 days of @entity189 . The prognostic value of these factors therefore needs to be re-evaluated for irradiated @entity1 .
