Anti-HER2 agents were a breakthrough in the treatment of HER2-enriched breast cancer (BC). In this study, we aimed to describe the real-life efficacy and safety of pertuzumab-trastuzumab-taxane (PTT) combination in BC patients.
This study was conducted by the Turkish Oncology Group and reached 35 centers nationwide. 309 visceral metastatic, and trastuzumab naive patients who received first line PTT were included.
Patients' characteristics and treatment details are summarized in the table. Median progression-free survival (PFS) was 28.5 months (95% CI:15.6-41.4), while median overall survival (OS) was 40.3 months (95%CI: 26.9-53.7). Brain metastatic patients (n = 13, 4.2%) had worse PFS (16.8m vs. 28.5m; HR:3.9, 95% CI:1.7-9.2, p = 0.002) and OS (26.7m vs. 40.3m; HR:3.2, 95% CI:1.3-7.6, p = 0.009). Elderly patients (>65y) had significantly lower OS results (19.8m vs. 40.3m; HR:0.4, %95 CI:0.2-0.8, p = 0.01). Docetaxel was the choice in 268 patients (86.7%), while 41 patients (13.3%) received paclitaxel. There was no statistically significant difference in PFS (28.5 m vs. 24.1 m; p = 0.61) and OS (40.3 m vs. NR; p = 0.17) between taxane groups. Additionally, ≥10 cycles of docetaxel were not associated with improvement in outcomes compared with 6-10 cycles. One treatment-related death due to sepsis was noted. In 8 patients (2.6%), 5-40% ejection fraction decrease from baseline was detected without any sign of heart failure. Demographic characteristics and treatment details IDC: Invasive Ductal Carcinoma ILC: Invasive lobular carcinoma LN: Lymph Node
N = 309 % Median age (year, range) 51 (22-82) >65 years-old patients 39 12.6 De-novo metastatic patients 258 83.5 Histopathology IDC 290 93.9 ILC 3 1 Mixt 5 1.6 Others 11 3.5 Hormone receptor status ER and/or PR positive 170 55.2 ER/PR negative 138 44.8 Unknown 1 0.3 Metastatic site distribution Liver ± LN/skeletal 112 36.3 Lung ± LN/skeletal 120 38.8 Brain only 6 1.9 Brain + liver + lung 7 2.3 Liver + lung 16 5.2 Other 48 15.5 Only skeletal or only LN - - Prior therapies Prior anthracyclines 51 16.5 Prior trastuzumab NA NA Treatment details Median number of cycle (range) Pertuzumab-trastuzumab 10 (1-75) Docetaxel 6 (1-23) Paclitaxel 3 (1- 26)
Demographic characteristics and treatment details
IDC: Invasive Ductal Carcinoma ILC: Invasive lobular carcinoma LN: Lymph Node
This real-life practice population differs from the CLEOPATRA study in terms of visceral only metastatic disease, and inclusion of brain metastatic patients. Regardless of these negative prognostic characteristics, results are concordant with the pivotal study. Elderly patients had overall lower PFS, which necessitates further investigation of pertuzumab-trastuzumab combination with cytotoxic/antihormonal therapies. To our knowledge, this is the largest scale real-life clinical practice study of PTT to date.
Ece ESIN, on behalf of Turkish Oncology Group.
Has not received any funding.
All authors have declared no conflicts of interest.