You can start with the pathology report, imaging, and treatment records you already have. Provide the complete pathology report whenever possible. It should show the diagnosis, specimen site, test date, immunohistochemistry, and molecular or genetic results.
A hospital may request pathology slides, paraffin blocks, or digital pathology files for diagnostic review. First confirm which institution holds them. Ask whether its process allows release, transfer, or digitization. Do not send pathology materials before the receiving hospital gives clear instructions.