What would be your treatment approach in a premenopausal BRCA2+ patient with cT2N0 grade 2-3, ER negative, PR variably positive (30%; staining weak to high), HER2 negative breast cancer?

Since weakly hormone-positive, HER2-negative breast cancer behaves more similarly to triple-negative breast cancer than strongly hormone receptor-positive breast cancer (Poterala et al., PMID 35676188), I would approach this patient similarly to patients with stage 2 triple-negative breast cancer. I would offer her neo-adjuvant chemo-immunotherapy per the KEYNOTE-522 regimen. Following breast surgery, adjuvant systemic therapy would depend on whether or not she had complete pathologic response (...

Yes, I would treat as TNBC with KN522 and if not a pCR, give adjuvant olaparib with pembro.

I agree - would treat at TNBC with KN-522