Accuracy of Preoperative Biopsies Compared With Surgical Specimens in the Diagnosis of Colorectal Adenocarcinoma

Objective Since the first data from a patient with colorectal adenocarcinoma are obtained by biopsy, this study evaluated the accuracy of diagnosis by biopsy as compared with the diagnostic potential of the surgical specimen, considering the histological type, grade of differentiation, and immunohistochemical expression of p53. Methods. The specimens were obtained from 80 patients assisted at Hospital São Paulo. The biopsy and surgical specimen sections were stained by hematoxylin–eosin and immunohistochemistry and compared by 3 pathologists blinded to the evaluations. Results. The accuracy for the histological types was 88%. The grade of differentiation presented an accuracy of 70% with Kappa = .48. The expression of protein p53 exhibited an accuracy of 68% with Kappa = .22. Conclusion. The preoperative biopsy of colorectal adenocarcinoma presented good accuracy compared with histopathological examination of the surgical specimen, but with weak to moderate effective degree of agreement between the results.