Biopsy-Resection Agreement of Peritoneal Histopathological Growth Patterns in Colorectal Peritoneal Metastases: A Prospective Observational Pilot Study

his prospective, single-center observational pilot study evaluates whether peritoneal histopathological growth patterns can be assessed on limited excisional biopsies obtained during staging laparoscopy in adults with suspected or confirmed colorectal peritoneal metastases. The study primarily evaluates agreement between the dominant histopathological growth pattern identified on laparoscopic biopsy and that identified on subsequent operative specimens. One to three peritoneal deposits will be sampled during staging laparoscopy. When surgery proceeds, up to three peritoneal deposits will be collected from the operative specimen, preferably from corresponding Peritoneal Cancer Index regions. Two pathologists, blinded to clinical information, specimen timing, and each other's assessments, will independently estimate the proportions of pushing and infiltrating growth patterns. Histopathol