Pathologist REasoning-Guided REport Generation Challenge

Pathologist REasoning-Guided REport Generation Challenge is a medical AI competition where teams build models that generate pathology reports from whole slide images and explain their reasoning while doing it. It builds on last year's REG2025, which focused only on matching reference reports. This time, the bar is higher: models need to show structured diagnostic thinking, the way a pathologist would walk a colleague through their findings. Evaluation now goes beyond surface-level text metrics to assess clinical correctness and reasoning quality. The challenge runs from May through July 2026, with top teams announced at MICCAI 2026 in October.