Neoadjuvant pertuzumab, docetaxel, carboplatin, and trastuzumab (PTCH) regimen in patients with HER2 positive early, locally advanced, and oligometastatic breast cancer: Real-world Indian experience.
Authors: Gogia Ajay , Gupta Anshul , Batra Atul , Deo S.V.S , Mishra Ashutosh , Sharma Daya Nand , Saini Surendra Kumar , Mathur Sandeep , Sagiraju Hari Krishna Raju , Prasad Chandra Prakash 
Published: June 2024

e12556 Background: Pertuzumab/docetaxel/carboplatin/trastuzumab (PTCH) regimen constitutes one of the standard neoadjuvant treatments in human epidermal growth factor receptor-2 (HER2) positive breast cancer. The real-world outcomes of its use from the Indian sub-continent are lacking. Methods: We retrospectively reviewed the medical records of 114 HER2-positive BC patients presenting with nonmetastatic or oligometastatic disease and treated with a uniform PTCH regimen in a neoadjuvant setting at the All India Institute of Medical Sciences, New Delhi, India, between Jan 2015 to May 2023. Total six cycles of PTCH [pertuzumab (840 mg loading followed by 420 mg), docetaxel (75 mg/m2), carboplatin (AUC 6), trastuzumab (8 mg/kg loading followed by 6 mg/kg) q21 days] were administered with primary GCSF prophylaxis. The primary outcome was invasive disease-free survival (iDFS). The secondary outcomes included pathological complete response (pCR) rates, overall survival (OS), and toxicity. Adjuvant trastuzumab is used for patients achieving pCR, while for patients not achieving pCR option of adjuvant trastuzumab emtansine (T-DM1) or trastuzumab was decided based on patient affordability. Results: One hundred and fourteen (114) patients were included with a median age of 47 years (range, 23-70). Overall, 52 (45.6%) patients had hormone-positive disease and 73 (64.01%) were premenopausal. Forty patients (35.08%) had stage II, 62 (54.38%) had stage III, and 12(10.5%) had oligometastatic disease. Sixty-one (53.5%) patients underwent breast conservation surgery and pCR was observed in 62 (54.38%) cases. With a median follow-up of 31 months, the 3-year iDFS was 81.5% and overall OS was not reached. Median iDFS was 33 months in patients with node-positive disease and was not reached in patients with node-negative disease. Three-year iDFS was 68.1% in patients who achieved pCR and 49.8% in those who did not achieve pCR (p=0.001). Grade 3/4 toxicity was seen in 26.7% of patients which caused dose modification and interruption in 13.9% of patients. The most common grade 3/4 toxicity was diarrhea in16 (14.03%) cases and thrombocytopenia in 11 (9.6)% cases . Febrile neutropenia was seen in 4 (3.5%) patients. Four patients (3.5%) had a reversible decrease in cardiac left ventricular ejection fraction. Conclusions: In a real-world context, PTCH is an effective and safe anthracycline-free regimen for use in curative (adjuvant and neoadjuvant) setting for HER2 positive breast cancer in Indian women Using neoadjuvant PTCH may improve pCR and obviate the need for adjuvant T-DM1 after surgery making it a cost-effective strategy in limited recourse setting. The survival outcomes were significantly better among those with node-negative disease and among those who achieved a pCR.