Impact of Pathologic Complete Response following Neoadjuvant Chemotherapy ± Trastuzumab in Locally Advanced Breast Cancer

Abstract

Purpose. This study was designed to examine the relationship between breast cancer molecular subtypes and pathological response to neoadjuvant chemotherapy (NAC) ± trastuzumab, in locally advanced breast cancer (LABC). Methods. Female patients with LABC (T2–T4, N0–N2, and M0) who received neoadjuvant chemotherapy + trastuzumab if HER2+ subtype, followed by surgery and radiotherapy ± hormonal therapy, were identified. The primary endpoint was pathologic complete response (pCR) in the breast and axilla (ypT0/ypN0), with final analysis on disease-free survival (DFS) and overall survival (OS). Results. Six hundred eighty-one patients with a median age of 44 years, premenopausal: 70%, median tumour size: 7.0 cm (range 4–11 cm), stage II B: 27% and III A/III B: 73%, ER+/HER2−: 40.8%, ER−/HER2−: 23%, ER+/HER2+: 17.7%, and ER−/HER2+: 18.5%. Overall pCR (ypT0/ypN0) was 23%. The pCR rates based on molecular subtypes were ER+/HER2−: 9%; ER+/HER2+: 29%; ER−/HER2−: 31%; and ER−/HER2+: 37%. At median follow-up of 61 months, ER+/HER2+ and ER+/HER2− subtypes had the best 5-year DFS and OS; meanwhile, ER−/HER2+ and ER−/HER2− subtypes had the worst. Conclusion. Women with ER+/HER2− disease are the least likely to achieve pCR, with the highest rates in HER2+ and triple-negative subgroups. Degree of response is associated with OS; despite the comparatively higher likelihood of achieving pCR in ER−/HER2+ and triple-negative, these subgroups experience a survival detriment. We are consistent with the published data that patients who attain the pathological complete response defined as ypT0/ypN0 have improved outcomes.

Neoadjuvant Therapy in Nonmetastatic Breast Cancer in Kurdistan, Iraq

“…The prognostic value of pCR after NACT depends on the molecular subtype of breast cancer 49 ; TNBC and HER2-enriched patients have higher pCR rates than luminal breast cancer. 50 Thirty-three (29.2%) patients achieved pCR, 9 (7.9%) had luminal breast cancer, 21 (18.6%) had HER2 overexpression tumors, and 3 (2.7%) had TNBC. 51 , 52 …”

Investigation of efficacy of two different chemotherapy protocols used in neoadjuvant chemotherapy in clinical stages II–IV canine malignant mammary tumours

“…pCR is directly related to subtypes of HBC, and research is ongoing into the use of molecular subtypes in HBC to predict the clinical efficacy of NAC 33 . pCR rate was found to be very low in ER‐positive and HER2‐negative patients in HBC, and it was observed that the best responses to NAC were obtained in HER2‐positive patients, followed by triple‐negative breast cancer (TNBC) patients 34 . The pCR rates in Luminal A and B subtypes are expressed as 0.3%–6% and 8.3%, respectively.…”

“…33 pCR rate was found to be very low in ER-positive and HER2-negative patients in HBC, and it was observed that the best responses to NAC were obtained in HER2-positive patients, followed by triple-negative breast cancer (TNBC) patients. 34 The pCR rates in Luminal A and B subtypes are expressed as 0.3%-6% and 8.3%, respectively. The CR rate is 7.1% in the Luminal A subtype.…”

Technetium-99-Guided Axillary Lymph Node Identification: A Case Report of a Novel Technique for Targeted Lymph Node Excision Biopsy for Node Positive Breast Cancer After Neoadjuvant Chemotherapy

“…Similar to the response of the primary cancer in the breasts, the biopsy-proven positive axillary lymph nodes may achieve a pCR to neoadjuvant systemic therapy. Rates of 47-79% axillary nodal pCR are commonly reported, especially in triple negative or HER2 overexpressed invasive breast cancer [30][31][32][33][34]. If axillary nodal pCR is suspected based on the clinical/radiological response, the options for axillary staging include ALND, SLNB, excision of marked axillary nodes and targeted ALND.…”