#1: Solid Tumor Rules (2018, 2021)
Source 1: 2021 Solid Tumor Rules
Notes: Cutaneous Melanoma, December 2020 Update
Solid Tumor Rules (2018, 2021)/Histology--Melanoma: In what situation will Rule H4 be used to code the histology to regressing melanoma? See Discussion.
Rule H4 states: Code 8723/3 (malignant melanoma, regressing) when the diagnosis is regressing melanoma. However, if the diagnosis was strictly regressing melanoma or malignant melanoma, regressing, the first rule that applies is Rule H1 because regressing melanoma is a single, specific histologic type and Rule H1 states: Code the histology when only one histologic type is identified. Following the current rules, one would never arrive at Rule H4. Should the H Rules be reordered? Or should an example of when one would use Rule H4 be added to clarify when to use this rule?
Coding regressing melanoma has been an issue as registrars may not realize it is a reportable histology. Hence, H4 was written to reinforce correct histology. A note will be added to H1 instructing registrars to continue thru rules when the diagnosis is regressing melanoma.