Association between pertuzumab-associated diarrhoea and rash and survival outcomes in patients with HER2-positive metastatic breast cancer: Exploratory analysis from the CLEOPATRA trial.

BACKGROUND: Skin rash and diarrhoea are known side-effects of pertuzumab. Studies with other anti-HER2 agents suggested that adverse events correlate with patient outcomes. In this exploratory cohort of patients with metastatic HER2-positive breast cancer included in the CLEOPATRA trial we evaluated the value of rash and diarrhoea as prognostic markers and as predictors of pertuzumab benefit. METHODS: This is a retrospective analysis of the multicenter, prospective, randomised CLEOPATRA trial. We defined two analytic cohorts: cohort 1 (C1) included patients from treatment initiation, and cohort 2 (C2) included patients after discontinuation of docetaxel. A landmark analysis was introduced to deal with immortal-time bias. Study endpoints were progression-free survival (PFS) and overall survival (OS). Univariable and multivariable Cox proportional hazards models were used. RESULTS: Of the 808 patients and after application of the landmark analysis, C1 and C2 included 777 and 518 patients, respectively. In C1, rash occurred in 271 patients (34.9%) and diarrhoea in 470 (60.5%). Rash was prognostic for PFS and OS (C1: adjusted hazard ratio [aHR] = 0.66 [95% CI = 0.48-0.91], p = 0.010]; C2: aHR 0.52 [95% CI = 0.30-0.89], p = 0.018) in both cohorts, while diarrhoea was only prognostic for PFS in cohort 2 (aHR = 0.65 [95% CI = 0.46-0.91], p = 0.011). Rash and diarrhoea were not predictive of pertuzumab benefit (in terms of PFS/OS) in the two cohorts. CONCLUSIONS: In patients treated with pertuzumab, trastuzumab, and docetaxel, rash is prognostic whenever it occurs during treatment, while diarrhoea only has prognostic value when occurring after docetaxel discontinuation. However, neither rash nor diarrhoea predict pertuzumab benefit.

Variation in type of adjuvant chemotherapy received among patients with stage I breast cancer: A multi-institutional Portuguese cohort study.

BACKGROUND: A contemporary US study showed an increase in the use of chemotherapy in the last decade for some patients with stage-I breast cancer; with a rise in more intensive regimens, and declining use of anthracyclines. Nevertheless, there is still uncertainty on the absolute benefit of chemotherapy for these patients and the optimal regimen. In this study we compare those findings with the patterns of care among a Portuguese cohort of stage-I breast cancers. METHODS: Retrospective cohort study of patients with stage-I breast cancer diagnosed from 2006 to 2008 at four Portuguese institutions. The use and type of chemotherapy was evaluated. RESULTS: Among patients with stage I-III breast cancer 39.4% (n = 682) had stage I disease. Of the 595 eligible patients, 22.4% were treated with chemotherapy, 33.9% aged <55 years vs. 12.7% aged >65 years (p < 0.001). Thirteen percent of patients with hormone receptor (HR)+/HER2- tumors, 52.7% of patients with HER2+ and 66.0% of patients with HR-/HER2- received chemotherapy (p < 0.001). In addition, we found inter-institutional variability, with the use of chemotherapy ranging from 0.0% to 43.4% (p < 0.001). Eighty-five percent of patients treated with chemotherapy received less-intensive regimens with anthracycline-based regimens, such as doxorubicin and cyclophosphamide, being the most frequently used, while docetaxel and cyclophosphamide was only used in 1.5% of cases. CONCLUSIONS: Overall, almost one-quarter of patients received chemotherapy with institutional variability. When treated, mostly less-intensive associations including anthracyclines were used, which contrasts with contemporary US practice. This study highlights the need for health-services research to understand local practices and tailor quality improvement interventions.