Molecular Testing in Solid Tumors: Best Practices from the Molecular Pathology and Precision Medicine Study Group of the Italian Society of Pathology (PMMP/SIAPeC) - Part III - Post-analytical phase

Precision oncology requires standardized and clinically meaningful reporting of molecular test results to support therapeutic decision-making. Next-generation sequencing (NGS), increasingly used in routine diagnostics, must be accompanied by clear, structured, and up-to-date interpretative reports. This document provides updated guidance for the annotation, interpretation, and reporting of variants detected through NGS, encompassing both small targeted panels and large-scale comprehensive genomic profiling (CGP) assays. Emphasis is placed on structured reporting, clinical applicability, and harmonization across institutions. The recommendations also address critical aspects of quality assurance, standardization for both tissue and liquid biopsy samples, with the aim to streamline molecular report generation, improve multidisciplinary communication, and facilitate the integration of NGS into everyday oncology practice in Italy.