José Luiz Pedrini

Are the Pure In Situ Breast Ductal Carcinomas and Those Associated With Invasive Carcinoma the Same

It has been reported that pure ductal carcinoma in situ of the breast has morphologic differences from the in situ component of the invasive ductal carcinoma, as well estrogen and progesterone receptors expression according to their cytokeratin expression. However, there is no data comparing other tumor markers without using the cytokeratin expression. The objective of this study is to compare the expression of estrogen receptor (ER) and progesterone receptor (PR), HER-2/neu, p53, and Ki67 between pure ductal in situ carcinoma (pDCIS) and the in situ component of the invasive ductal carcinoma (DCIS+IDC) of the breast, and the in situ component to the invasive component of the same tumor (DCIS+IDC). The immunohistochemistry expression of the tumor markers was performed in 45 cases of pDCIS and DCIS+IDC, yielding a total of 90 cases. Statistical analysis was carried out using Fisher exact test, having a P<0.05, and Kappa index (κ) to assess intratumoral concordance. In DCIS+IDC, the in situ and invasive components did not show a significant difference and Kappa index (κ) was high (0.7-1) for positive and negative expression. ER and PR were significantly different between the pDCIS and DCIS+IDC (ER: 86.7 vs. 66.7% P=0.04; PR: 80% vs. 55.6% P=0.02). These findings suggest that in situ component of DCIS+IDC and pDCIS are distinct conditions.

How to identify patients with increased risk of breast cancer relapse

A cohort of 362 breast cancer patients had subtype classification accomplished using 4 immunohistochemical markers: luminal A (ER or PR positive, HER2 negative, Ki-67<14%), luminal B (ER or PR positive, HER2 negative, Ki-67≥14%), luminal HER2 (ER or PR positive, HER2 positive), HER2 enriched (ER or PR negative, HER2 positive) or triple negative (ER, PR, and HER2 negative). Multivariable Cox analysis was used to determine the risk of local (LR) or distant (DR) relapse associated with the intrinsic subtypes, adjusting for standard clinicopathologic factors. There have been a total of 124 recurrences. Triple-negative patients were associated with increased risk of LR. Luminal B subtype showed statistical tendency (P=0.053) to LR. For patients undergoing breast conservation surgery, luminal B and HER2-enriched subtypes demonstrated an increased risk to LR, and this was statistically significant on multivariable analysis. After mastectomy, there was no statistical difference between subtypes of LR or DR on multivariable analysis. Luminal A tumors are associated with a low risk of LR or DR. Despite the existence of gene expression profiling, in the current study we demonstrate that analysis of 4 immunohistochemical markers is equally effective and less expensive alternative to identify higher recurrence risk patients.