Defining the T status in breast cancer: Where do we stand?

Abstract

Background: Tumor size in breast cancer is a key factor for staging, prognosticating, and deciding the choice of treatment. Currently, there are no standard rules for measuring the T status in breast cancer. The purpose of this study was to determine an accurate method to evaluate the T status by various parameters compared with the actual size in fresh specimens. Materials and Methods: This prospective study was conducted on 134 breast cancer patients scheduled to undergo a modified radical mastectomy. The paired t-test was used for analyses. Results: Using a paired t-test, the differences in tumor size as measured by physical examination (P ≤ 0.001) and in the formalin-fixed specimen (P ≤ 0.001) when compared with the postoperative fresh specimen were highly significant. These differences indicated that the physical examination and formalin-fixed specimen measurements were inaccurate in estimating tumor size. Tumor size, as measured by a mammogram and ultrasonogram when compared with the referenced P= 0.077 and 0.149, respectively, showed that the ultrasonogram is the most accurate method of determining tumor size in vivo. The mean percentage decrease in size of the formalin-fixed specimen was 7.8, which was significant enough to downstage two patients from T2 to T1 and seven patients from T3 to T2. Conclusion: An ultrasonogram is the most accurate way of defining tumor size in vivo as measured in postoperative fresh specimens. Tumor shrinkage with formalin fixation may give a false T status.