Preoperative pathological diagnosis of breast cancer *
Several methods are available for the pathological diagnosis of breast lesions, such as fine-needle aspiration cytology (FNAC) and core-needle biopsy (CNB). However, FNAC occasionally cannot identify lesions or unsuitable samples, and is unable to provide a diagnosis in some cases. Therefore, there has been a recent increase in the use of CNB, a minimally invasive technique of obtaining histological samples, is being used from the beginning. However, the fact that diagnosis is performed only on a part of the lesion continues to cause problems in determining the tissue type and whether there is infiltration. We investigated the accuracy of FNAC and CNB testing in 180 primary breast cancer patients, who had undergone surgery without preoperative therapy at our facility over the course of 1 year from January 2010 to December 2010. Of the 59 patients who underwent preoperative FNAC, 39 were diagnosed as “malignant,” 7 as “suspicious of malignancy,” 7 as “indeterminate,” 4 as “normal or benign,” and 2 as “inadequate.” With a sensitivity of 66.1%, FNAC showed difficulty in diagnosing ductal carcinoma in situ (DCIS), small-diameter papillotubular carcinoma, and scirrhous carcinoma. There were 138 patients who underwent preoperative CNB. CNB results for invasive ductal carcinoma (IDC) and other special types of carcinomas had a high rate of concordance with the final pathological diagnosis. However, 62.1% of patients diagnosed as having DCIS by CNB ultimately had IDC. While determining hormone receptor sensitivity with CNB, a high correlation was observed with the final pathological diagnosis, which was thought to reflect the overall picture of cancer. Of the patients who scored 3+ for HER2 overexpression for the Hercep test on a CNB specimen, 75% were ultimately positive for HER2. However, of the patients who scored 2+ with CNB specimens, 16.6% were ultimately positive for HER2, and many were negative for HER2 in the final pathological diagnosis. We feel that although HER2 evaluation using CNB specimens can be helpful, there is a need to improve its sensitivity and positive predictive value, and that it should be supplemented with the FISH method if needed. (Accepted on October 31, 2011)
