Prognostic factors for recurrence-free survival in patients with HER2-positive early-stage breast cancer treated with adjuvant trastuzumab.

BACKGROUND: The objective of this study was to identify prognostic factors affecting the recurrence-free survival (RFS) in patients who received a 52-week trastuzumab therapy for HER2-positive early stage breast cancer (EBC). PATIENTS AND METHODS: The medical records of all patients with EBC from 10 centers were analyzed. Pathologic and clinical tumor characteristics were evaluated in 424 female patients who received 52 weeks of adjuvant trastuzumab for HER2-positive EBC. Survival was estimated using the Kaplan-Meier method. Univariate analyses of RFS were performed with the log-rank test. Independent prognostic and predictive factors affecting RFS were assessed by Cox regression analysis. RESULTS: Median follow-up time was 33.1 months (range 9.2-75.9 months). 3-year RFS and overall survival were 87 and 97%, respectively. In multivariate analysis, patients aged 70 years or over (p = 0.017, relative risk (RR) 2.7, 95% confidence interval (CI) 1.19-6.13), patients with > 9 positive lymph nodes (p = 0.001, RR 2.52, 95% CI 1.42-4.46), and those with progesterone receptor-negative tumors (p = 0.006, RR 2.33, 95% CI 1.27-4.27) had worse RFS. CONCLUSION: In spite of a 52-week adjuvant trastuzumab treatment, classic poor prognostic factors for invasive EBC remained as such in patients with HER2-positive EBC.

The effect of low HER2 expression on treatment outcomes in metastatic hormone receptor positive breast cancer patients treated with a combination of a CDK4/6 inhibitor and endocrine therapy: A multicentric retrospective study.

BACKGROUND: CDK4/6 inhibitors combined with endocrine therapy have significantly improved treatment outcomes for metastatic hormone receptor-positive (HR+) breast cancer patients. However, the impact of low HER2 expression on treatment response and progression-free survival (PFS) remains unclear. METHODS: This multicenter retrospective study included 204 HR+ breast cancer patients treated with a combination of CDK4/6 inhibitor and endocrine therapy. HER2-zero disease was detected in 138 (68%) and HER2-low disease in 66 (32%) patients. Treatment-related characteristics and clinical outcomes were analyzed, with a median follow-up of 22 months. RESULTS: The objective response rate (ORR) was 72.7% in the HER2 low group and 66.6% in the HER2 zero group (p = 0.54). Median PFS was not significantly different between the HER2-low and HER2 zero groups (19 months vs.18 months, p = 0.89), although there was a trend toward longer PFS in the HER2-low group for first-line treatment (24 months progression-free survival rate 63% vs 49%). In recurrent disease, the median PFS was 25 months in the HER2-low group and 12 months in the HER2-zero group (p = 0.08), while in de novo metastatic disease, the median PFS was 18 months in the HER2-low group and 27 months in the HER2-zero group (p = 0.16). The order of CDK4/6 inhibitor use and the presence of visceral metastasis were identified as independent variables affecting PFS. CONCLUSION: Low HER2 expression did not significantly impact treatment response or PFS in HR+ breast cancer patients treated with a CDK4/6 inhibitor and endocrine therapy. Because of the conflicting results in the literature, further prospective studies are needed to evaluate the clinical significance of HER2 expression in HR+ breast cancer.

EGFR mutation status in a series of Turkish non-small cell lung cancer patients.

Epidermal growth factor receptor (EGFR) mutations are potential markers driving carcinogenesis, and may alter the response to EGFR tyrosine kinase inhibitors in patients with non-small cell lung cancer (NSCLC). The frequency of EGFR mutations in patients with NSCLC differs according to sex, smoking habits and regional-based ethnicity differences. The aim of the present study was to determine the frequency of EGFR mutations in Turkish patients with NSCLC to highlight the importance of regional differences, and their associations with patient characteristics. Genomic DNA was extracted from formalin-fixed and paraffin-embedded tumor tissue sections of 409 NSCLC patients. The most common EGFR mutations in exons 18, 19, 20 and 21 were detected using BioFilmChip-based microarray assay. The overall EGFR mutation frequency was 16.6%, and the highest mutation frequencies were observed in exon 19 (6.4%) and exon 21 (7.3%). There was a higher frequency of EGFR mutations in females compared with males and in never-smokers compared with smokers (both P≤0.05). These results were similar to other European population-based studies, but not consistent Middle-Eastern based studies. The present study may contribute to understanding the gradient frequency of EGFR mutation across different ethnicities, and in designing genome wide-based collaborations that may reveal novel decision making and susceptibility mutations in EGFR in patients with NSCLC.