Colorectal Cancer OncoGuia: surgical pathology report guidelines

Abstract

The guidelines below have been developed in the framework of the Colorectal Cancer OncoGuia [1] and are aimed at standardising descriptions of diagnoses in colorectal cancer pathology reports so that these are fully comparable regardless of the pathologist who issues the diagnosis [2-6].

Clinical practice guidelines for the surgical treatment of rectal cancer: a consensus statement of the Hellenic Society of Medical Oncologists (HeSMO)

“…The gross description of the histology report must include the length of surgical specimen, the location of the tumor (at or below the peritoneal reflection, or the distance from the dentate line if an abdominoperineal excision is performed, the tumor size (3 dimensions), the length of proximal and distal margins, the depth of invasion, tumor perforation, other lesions not related with the tumor such as Crohn’s disease, ulcerative colitis, polyp, familial adenomatous polyposis, and the number of lymph nodes retrieved. Blocks should be taken from the area closest to the CRM and any area where the tumor extends to within less than 3 mm from the margin [ 166 , 167 , 169 , 171 ].…”

“…Standard microscopic description must include: i) histologic type , according to WHO classification. Mucinous component, presence of signet ring carcinoma (>50% signet ring), and medullary carcinomas should be mentioned, as these elements affect prognosis [ 166 , 168 , 170 , 172 ]; ii) histologic grade (low grade: >50% glandular formation; high grade: <50% glandular formation) [ 168 , 171 , 172 ]; iii) T status . In pT1 lesions, distance of tumor from the resection margin, vascular or lymphatic invasion and the depth of invasion into submucosa must be reported [ 172 ]; iv) total number and number of involved lymph nodes (≥12 lymph nodes must be found to predict actual lymph node status).…”

“…Any node containing malignant cells, irrespective of size and even with smooth contour is considered as involved. Extramural tumor nodules measured >3 mm without evidence of residual lymph node tissue are considered as positive lymph nodes [ 23 , 167 , 168 , 171 , 172 ]; v) blood, lymphatic vessel, tumor budding, and perineural invasion (each one an independent prognostic factor) [ 23 , 166 , 168 , 170 , 172 ]; vi) presence of tumor infiltrating lymphocytes ; and vii) surgical margin status and residual tumor classification [R classification system with four different grades: Rx (presence of residual tumor cannot be assessed), R0 (no residual tumor - distance from the closest margin must be reported), R1 (microscopic residual tumor) and R2 (macroscopic residual tumor)] [ 23 , 168 , 171 , 172 ]. The pTNM system or ypTNM system (5th edition) is applied in the classification of rectal cancer [ 23 , 166 , 168 , 171 , 172 ].…”

Guidelines for biomarker testing in colorectal carcinoma (CRC): a national consensus of the Spanish Society of Pathology (SEAP) and the Spanish Society of Medical Oncology (SEOM)

“…Consensus protocols drawn up by various pathologists' associations regularly review the information to be contained in pathology reports, and are updated in line with changes made to the TNM classification [68,69]. Notable new features in the seventh edition of the TNM classification of malignant tumours are as follows [70]:…”