OBJECTIVE: To compare cardiac safety and efficacy between SB3 and TRZ for patients with ERBB2-positive early or locally advanced breast cancer after up to 6 years of follow-up.

DESIGN, SETTING, AND PARTICIPANTS: This prespecified secondary analysis of a randomized clinical trial, conducted from April 2016 to January 2021, included patients with ERBB2-positive early or locally advanced breast cancer from a multicenter double-blind, parallel-group, equivalence phase 3 randomized clinical trial of SB3 vs TRZ with concomitant neoadjuvant chemotherapy who completed neoadjuvant and adjuvant treatment.

INTERVENTIONS: In the original trial, patients were randomized to either SB3 or TRZ with concomitant neoadjuvant chemotherapy for 8 cycles (4 cycles of docetaxel followed by 4 cycles of fluorouracil, epirubicin, and cyclophosphamide). After surgery, patients continued SB3 or TRZ monotherapy for 10 cycles of adjuvant treatment per previous treatment allocation. Following neoadjuvant and adjuvant treatment, patients were monitored for up to 5 years.

MAIN OUTCOMES AND MEASURES: The primary outcomes were the incidence of symptomatic congestive heart failure and asymptomatic, significant decrease in left ventricular ejection fraction (LVEF). The secondary outcomes were event-free survival (EFS) and overall survival (OS).

RESULTS: A total of 538 female patients were included (median age, 51 years [range, 22-65 years]). Baseline characteristics were comparable between the SB3 and TRZ groups. Cardiac safety was monitored for 367 patients (SB3, n = 186; TRZ, n = 181). Median follow-up was 68 months (range, 8.5-78.1 months). Asymptomatic, clinically significant LVEF decreases were rarely reported (SB3, 1 patient [0.4%]; TRZ, 2 [0.7%]). No patient experienced symptomatic cardiac failure or death due to a cardiovascular event. Survival was evaluated for the 367 patients in the cardiac safety cohort and an additional 171 patients enrolled after a protocol amendment (538 patients [SB3, n = 267; TRZ, n = 271]). No difference was observed in EFS or OS between treatment groups (EFS: hazard ratio [HR], 0.84; 95% CI, 0.58-1.20; P = .34; OS: HR, 0.61; 95% CI, 0.36-1.05; P = .07). Five-year EFS rates were 79.8% (95% CI, 74.8%-84.9%) in the SB3 group and 75.0% (95% CI, 69.7%-80.3%) in the TRZ group, and OS rates were 92.5% (95% CI, 89.2%-95.7%) in the SB3 group and 85.4% (95% CI, 81.0%-89.7%) in the TRZ group.

CONCLUSIONS AND RELEVANCE: In this secondary analysis of a randomized clinical trial, SB3 demonstrated cardiac safety and survival comparable to those of TRZ after up to 6 years of follow-up in patients with ERBB2-positive early or locally advanced breast cancer.

OBJECTIVE: This study aimed to assess the determinants of surgery choice in Asian patients with early breast cancer in a middle-income country.

MATERIALS AND METHODS: 184 patients with early breast cancer treated between Jan 2008 and Dec 2010 were recruited to complete a questionnaire. Chi-square test was used to analyze the association between surgery choice and demographic and tumour factors, surgeon recommendation, family member and partner opinions, fear of recurrence, avoidance of second surgery, fear of disfigurement, interference with sex life, fear of radiation and loss of femininity.

RESULTS: 85 (46%) had BCS while 99 (54%) had mastectomy. Age >60, Chinese ethnicity, lower education level, and larger tumour size were significantly associated with mastectomy. Surgeon recommendation was important in surgery choice. Although both groups did not place much importance on interference with sex life, 14.1% of the BCS group felt it was very important compared to 5.1% in the mastectomy group and this was statistically significant. There was no statistical difference between the two groups in terms of the other factors. When analyzed by ethnicity, significantly more Malay and Indian women considered partner and family member opinions very important and were more concerned about loss of femininity compared to Chinese women. There were no statistical differences between the three ethnic groups in terms of the other factors.

METHODS: Two prospective groups of 423 and 965 newly diagnosed breast cancer patients in University of Malaya Medical Centre, Kuala Lumpur, Malaysia diagnosed in two time periods ie. 1993 to 1997 and in 1998 to 2002 were studied. Vital status was obtained from the National Registry of Births and Deaths. The overall survival was calculated from the date of diagnosis to the date of death from any cause. The survival differences between the two groups were analysed using the log-rank or Peto-Wilcoxon method. Survival estimates and independent prognostic factors were estimated by the Kaplan-Meier method and multivariate analysis using Cox proportional hazard models. P values less than 0.05 were considered statistically significant. Analyses were performed using SPlus 2000 Professional Release 2.

RESULTS AND DISCUSSION: Median follow-up for the two groups were 55 months (SD 29.2 months) in the first group and 52 months (SD 24.43) in the second group. There was improvement in 5-year observed survival from 58.4% (CI 0.54-0.63) to 75.7% (CI 0.73-0.79). The improvement in survival was significantly seen in all co-variates (p< 0.05) except for those aged 40 years and below (p= 0.27), tumour size 2 to 5 cm (p=0.11), grade 3 (p=0.32) and patients with Stage IV disease (p= 0.80). Stage of disease, lymph node (LN) involvement, size and grade were identified as independent prognostic factors in cohort one. For the second cohort; stage and LN involvement remained independent factors with the addition of ER status and ethnicity.