#1: Solid Tumor Rules (2018, 2021)
Source 1: 2018 Solid Tumor Rules
Notes: Colon; December 2020 Update
Solid Tumor Rules (2018)/Histology--Colon: What is the histology for a 2020 pathology report final diagnosis showing invasive adenocarcinoma, poorly differentiated with signet ring cell features and signet-ring cell carcinoma in the synoptic report? See Discussion.
Since the synoptic report and final diagnosis are equal in priority, and the Solid Tumor Rules tell us to code the more specific histology, would this be coded to signet ring cell adenocarcinoma, 8490/3, even though the pathologist used features in the final diagnosis? There is no histology adenocarcinoma with signet ring cell features on the CAP Protocol, so the pathologist may check off the next closest histology – signet ring cell carcinoma – which would not be truly representative of the actual histology. Final Diagnosis: Proximal colon, segmental resection: Invasive adenocarcinoma, poorly differentiated, with signet ring cell features. Synoptic Report A: Colon and Rectum - Resection Specimen Procedure: Right hemicolectomy, Tumor Site: Right (ascending) colon, Histologic Type: Signet-ring cell carcinoma, Histologic Grade: G3: Poorly differentiated.
Code histology to 8490/3 per H6.
The December 2020 Solid Tumor Update includes addition of the following instructions to the "Priority Order for Using Documentation to Code Histology" section.
Which document to use when there is conflicting information between the final diagnosis, synoptic report, or CAP protocol: When there are discrepancies between the final diagnosis and synoptic report, use the document that provides the more specific histology. This will likely be found in the synoptic report. The CAP Protocol should be used only when a final diagnosis or synoptic report are not available. Definitions for CAP Protocol, final diagnosis, and synoptic report can be found in the Definitions section.