Toripalimab Plus Celecoxib for dMMR/MSI-H Locally Advanced Colorectal Cancer

The PICC-3 study is a multicentre, single-arm, phase II trial evaluating toripalimab plus celecoxib in patients with mismatch repair-deficient (dMMR) or microsatellite instability-high (MSI-H) locally advanced colorectal cancer. The trial uses a response-adapted treatment strategy, whereby patients with clinical complete response (cCR) after therapy may enter a non-operative management pathway, while patients without cCR proceed to surgery. Response assessment is based on imaging, endoscopy, biopsy evaluation, and ctDNA analysis.