SUMMARY
At ESMO 2024, updated results of the KEYNOTE-522 study showed for the first time overall survival (OS) benefit when adding pembrolizumab to neoadjuvant chemotherapy in patients with early-stage triplenegative breast cancer (TNBC). In addition, real-world evidence indicated that oestrogen receptor (ER)-low human epidermal growth factor receptor 2 (HER2)-negative disease treated with the neoadjuvant KEYNOTE-522 regimen achieved very high pathological complete response (pCR) rates and should preferably be treated as TNBC. Updated results from the NATALEE trial further reinforced the efficacy of combining a cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor with endocrine therapy in patients with early-stage hormone receptor (HR)-positive breast cancer at risk of recurrence. Furthermore, preliminary evidence showed promising activity in patients with luminal B-like breast cancer treated with preoperative radiotherapy (RT) plus immuno-chemotherapy. Additionally, the HypoG-01 trial supports the use of hypofractionated RT (40 Gy/15 fractions in three weeks) to irradiate loco-regional nodes in patients with early-stage breast cancer. In the metastatic setting, the addition of capivasertib to first-line paclitaxel did not significantly improve survival in patients with TNBC. In addition, first-line treatment with CDK4/6 inhibitors and endocrine therapy confirmed efficacy for patients with HR-positive HER2-negative breast cancer with aggressive disease criteria compared to upfront chemotherapy. Moreover, in patients with HR-positive breast cancer, a large proportion of patients currently categorised as having tumours with an immunohistochemical (IHC) score of 0 at local testing, are HER2-low (IHC 1 or 2+) or ultralow (IHC >0 and <1) at retesting and can also benefit from trastuzumab deruxtecan (T-DXd). Finally, substantial and durable intracranial clinical activity was seen in patients with HER2-positive breast cancer with stable and active brain metastases treated with T-DXd.
(BELG J MED ONCOL 2024;18(8):294–302)
