A patient with locally advanced HER2-positive breast cancer receives neoadjuvant trastuzumab and pertuzumab with chemotherapy and achieves a pathological complete response (pCR) at surgery. According to the KATHERINE trial, what is the adjuvant treatment recommendation if pCR is NOT achieved?
- A Continue trastuzumab and pertuzumab for 1 year
- B Switch to trastuzumab emtansine (T-DM1) for 14 cycles ✓
- C Add capecitabine to trastuzumab
- D Olaparib for 1 year
Correct answer: B. Switch to trastuzumab emtansine (T-DM1) for 14 cycles
Explanation
The KATHERINE trial demonstrated that switching to trastuzumab emtansine (T-DM1) after neoadjuvant HER2-targeted therapy when there is residual disease (no pCR) improves invasive disease-free survival compared to continuing trastuzumab alone. T-DM1 is given for 14 cycles (approximately 14 months). This strategy is now the standard of care for HER2-positive breast cancer patients with residual disease after neoadjuvant treatment.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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