HER2 positive rates in invasive lobular breast carcinoma: A study amongst 1,095 consecutive Asian patients

Abstract

Background: TP53 mutation is the most common mutation in breast cancer, and it is considered a target marker of triple negative breast cancer (TNBC). The purpose of this study was to evaluate the prognosis of TNBC using only clinical information. The p53 status detected immunohistochemically was evaluated as a prognostic and predictive factor. Methods: Among KBCSR-registered patients, triple-negative breast cancer patients diagnosed between 2000 and 2015 were included. This included patients who were aged 20 years or older and had between stage I and stage III TNBC. A total of 11,393 patients were included in this study, including 6,331 'p53-positive TNBC' and 5,062 'p53-negative TNBC' cases. The median follow-up period was 60 months (1-188 months). Results: In univariate analysis, there was no difference in prognosis between p53þ TNBC and p53-TNBC for patients receiving chemotherapy. But, p53þ TNBC had a worse prognosis than p53-TNBC in patients not receiving chemotherapy (P ¼ 0.003). In multivariate analysis adjusted for age and cancer stage, the risk of p53þ TNBC was 1.84 times higher than that of p53-TNBC in the non-chemotherapy group. There was no difference between p53þ TNBC and p53-TNBC in patients receiving chemotherapy. In p53þ TNBC, the risk was 0.6-fold lower when chemotherapy was administered than when chemotherapy was not administered. In p53-TNBC, there was no risk reduction effect by chemotherapy. Conclusions: The prognosis of p53-TNBC is better than that of p53þ TNBC, but it shows no benefit of chemotherapy. p53þ TNBC has a poor prognosis but benefits from chemotherapy. In conclusion, p53þ TNBC appears to be more sensitive to chemotherapy than p53-TNBC.

Evaluation of HER2 Positivity Based on Clinicopathological Findings in HER2 Borderline Tumors in Iranian Patients with Breast Cancer

“…Our results do agree with others in that most cases of ILC with HER2 overexpression represented the pleomorphic variant (26). Kee et al reported a higher prevalence of HER2positive classic type ILC (10.8%) compared to the previous ILC case series (1-6%) (27). In the study of Prati et al, only three cases of 31 (9.7%) ILCs out of 200 breast cancer cases had positive HER2 results by FISH (10).…”