A single-cell rule at the invasive front of pT1 colorectal cancer, and the zone 3 pattern of CDK4/6 inhibitor liver injury

The edition in brief

In 2,611 resected pT1 colorectal cancers from six Chinese centres, peritumoral malignant cellular foci, defined as any non-glandular focus of one or more tumour cells at the invasive front, independently predicted lymph node metastasis in both training and validation cohorts, while tumour budding and poorly differentiated clusters did not do so consistently. The proposal removes the five-cell cutoff but needs external validation before it changes reporting. A single-centre series of seven women with metastatic breast cancer showed that CDK4/6 inhibitor liver injury, mostly with ribociclib, typically appears as acute hepatitis with zone 3 confluent necrosis and lymphocytic cholangitis, resolving after withdrawal; positive ANA did not mean autoimmune hepatitis. In 90 sequenced intrahepatic cholangiocarcinomas, FGFR2/3-altered tumours were small-duct, non-mucinous and TP53-poor, with better disease-specific survival on univariate but not multivariate analysis. Ex vivo fluorescence confocal microscopy matched histopathology on 96.4% of 261 Mohs margins. The pearl lists the pT1 colorectal high-risk features every report should carry.