PET-guided de-escalation of neoadjuvant treatment for HER2-positive breast cancer

The multinational phase 2 trial PHERGain found that ¹⁸F-FDG-PET identified patients with HER2-positive, early-stage breast cancer who were likely to benefit from chemotherapy-free dual HER2 blockade with trastuzumab and pertuzumab, and a reduced impact on global health status. Among 285 patients 227 (80%) had a PET response, and 86 of 227 (37.9%; 95% CI 31.6-44.5) had pathological complete response.