Solid Tumor Rules/Histology--Head and Neck, Other Sites: Do human papilloma virus (HPV) histologies that occur with subtype/variants of squamous cell carcinoma (SCC) in various sites apply only to sites in Solid Tumor Rules, Head and Neck, Table 5 and Other Sites, Table 23? See Discussion.
The 2024 Solid Tumor Rules, Table 5: Tumors of the Oropharynx, Base of Tongue, Tonsils, Adenoids contain notes that say beginning 1/1/2022, keratinizing or non-keratinizing SCCs, HPV positive or HPV negative, are coded 8085 or 8086, respectively, for sites listed in the Head and Neck Solid Tumor Rules, Table 5 only.
Table 5 introductory section also states for cases diagnosed 1/1/2023 forward: “When the diagnosis is a subtype/variant of squamous cell carcinoma and HPV status is also noted, code the subtype/variant.” This latter instruction is also included in Other Sites Table 23 (Penis and Scrotum Histologies) as a “Penis Coding Note.”
Do these instructions ONLY apply to sites on those tables (and only to Penis or to Scrotum also in Table 23)? How should we code HPV-related keratinizing/non-keratinizing or other subtype/variant SCCs, for sites NOT on those tables, given the fact that only the more common histologies are listed in the Solid Tumor tables? For example, we recently reviewed a case with HPV-positive basaloid squamous cell carcinoma of the anus (C21.0).
Code the specific histology as stated by the pathologist according to the site-specific instructions in the Solid Tumor Rules. When the histology provides a subtype/variant in addition to the HPV histology codes, code the subtype/variant as it is important to capture this histology as in the example provided. the instruction to code the subtype/variant over 8085 or 8086 applies to the following sites: oropharynx, cervix, vagina, vulva, anus, and penis. A note will be added indicatng this in 2025.
Per 2024 Cancer PathCHART expert pathologist review, morphology codes 8085/3 and/or 8086/3 are valid and applicable to head and neck, oropharynx, cervix, vagina, vulva, fallopian tube, anus, and penis (reference: Cancer PathCHART: Product Downloads and Timelines). Other coding resources will be updated to reflect these changes in 2025.
Solid Tumor Rules/Histology--Brain and CNS: Should the term “diffuse” be added to Note 2 in the Non-Malignant Central Nervous System (CNS) Solid Tumor Rules, Table 6: Specific Histologies, NOS, and Subtypes/Variants, for the papillary glioneuronal tumor 9509/1? See Discussion.
Should Note 2 state, "Beginning with cases diagnosed 1/1/2023 forward, diffuse leptomeningeal glioneuronal tumor is coded 9509/3? See the Malignant CNS rules." Currently the Note only states, "leptomeningeal glioneuronal tumor," but the histology that changed behavior is listed in both Table 6, Column 1 (Non-Malignant CNS) and Table 3 (Malignant CNS) as, "Diffuse leptomeningeal glioneuronal tumor."
The correct term is diffuse leptomeningeal glioneuronal tumor listed as a synonym in Column 2.
We will add the term diffuse in Note 2, Column 1 with the 2025 updates. In the meantime, you can add "diffuse" to your pdf version until the update is published.