SEER Inquiry System - Search

1.  The 2022 and 2023 SEER Program Coding Manuals state under Histologic Type ICD-O-3: Beginning with cases diagnosed 01/01/2022 forward, p16 test results can be used to code squamous cell carcinoma, human papilloma virus (HPV) positive (8085) and squamous cell carcinoma, HPV negative (8086).

NAACCR 2023 Implementation Guidelines contain similar instructions on HPV histologies for cervix, vulva and vagina that are applicable back to 2022 (2021 for cervix).

The current Other Sites Solid Tumor Rules state on the Histology tables for anus, cervix, vagina, vulva, and penis and scrotum: "p16 is a valid test to determine HPV status and can be used to code HPV associated and HPV independent histologies." Since Other Sites Solid Tumor Rules apply to cases diagnosed 2023+, can p16 results only be used from 2023 onward, to code HPV-related histologies for primaries that fall under the Other Sites module? Or per the 2022 SEER Manual statement and NAACCR 2023 Implementation Guidelines, could a p16-confirmed HPV histology code also apply to a 2022 Other Sites case and if so, is that only for cervix, vulva, and vagina? Further complicating the matter are the 2024 ICD-O-3.2 update documents indicating these codes are valid 1/1/2024+ for the “Other Sites” penis and scrotum.

2.  Is using p16 testing for HPV-related histology codes ONLY allowed for sites in the Solid Tumor tables that contain the statements about p16 (Head & Neck Table 5, and the Other Sites tables noted above for anus, cervix, etc.)? Or could it apply to primary sites outside of those tables; for example, a 2022 pathology report from the ethmoid sinus C311 indicating an HPV-related histology based on p16 testing? The ICD-O-3 Annotated Histology lists include C310-C313 among the common site codes for 8085 and 8086. The Head and Neck Solid Tumor Rules “New for 2022” section and rule H1 Note 4 also mention that p16 can be used to code HPV histologies; these sections would seem to apply to all sites in that module, since only the more common histology codes are listed in the tables and if not, we are instructed to use ICD-O.

We would like to confirm that the correct histology code is 9431/1 per ICD-O-3.2, as the Non-Malignant CNS Solid Tumor Manual lists the histology code as both 9431/1 (pages 301 and 303 of the combined manual), but also shows it as a synonym for 9421/1 – Diffuse astrocytoma, MYB- or MYBL1 altered (page 304).

The race category in some hospital electronic medical record systems includes a combined category of “Native Hawaiian/Pacific Islander.” What race code should be used in a situation where the only available information is “Native Hawaiian/Pacific Islander?”

The Solid Tumor Rules state that for cases diagnosed in 2022 and forward, p16 testing CAN be used to assign histology code 8085 (squamous cell carcinoma, HPV positive). The rules also state that for cases diagnosed prior to 1/1/2022, code 8085 MUST be based on ISH testing and not p16. ISH testing is not specifically addressed for 2022+ cases, but are we correct in assuming it can still be used as the basis for 8085?

Multiple CAnswer Forum posts and the AJCC 8th edition Head and Neck staging webinar indicate that the correct chapter/registry staging schema in this situation is determined ONLY by p16 results - not ISH testing, and therefore the Schema Discriminator 2 SSDI should be coded as 1 – p16 negative, regardless of ISH results.

While we understand that histology codes should not be changed based on staging criteria, there is a SEER/NAACCR edit, “Schema Discriminator 2, Head and Neck, Histology (NAACCR)” tag number N6802, that will not allow coding 8085 if Schema Discriminator 2 is coded as 1 (p16 negative). The edit does seem to be correctly enforcing the AJCC guidelines for choosing the staging schema, based on the sources noted above. Do the Solid Tumor or Site-Specific Data Items (SSDI) guidelines need to be modified for this situation?

In the NAACCR Coding Pitfalls 2023 webinar, the example of DCIS, solid type is given. The webinar advised us to code 8230/2 (ductal carcinoma in situ, solid type). When going through the beginning of the solid tumor rules in the Changes from 2007 MPH Rules section it states "DCIS/Carcinoma NST in situ has a major classification change. Subtypes/variant, architecture, pattern, and features ARE NOT CODED. The majority of in situ tumors will be coded to DCIS 8500/2." In the equivalent or equal terms section it lists "Type, subtype, variant" can be used interchangeably.

Since the example has it listed as as ductal carcinoma in situ, solid "type," would we code 8500/2 or 8230/2? 

Example: Patient had a 2023 nasopharyngeal mass biopsy showing “Nasopharyngeal non-keratinizing squamous cell carcinoma, undifferentiated type.” 

The Head and Neck Solid Tumor Rules (STRs) do not include an H Rule that instructs us how to code histology when there are two subtypes/variants present for a head and neck primary, nor does the STR define undifferentiated carcinoma as a subtype/variant for 8072.

The WHO Classification of Head and Neck Tumors states non-keratinizing nasopharyngeal carcinoma (non-keratinizing squamous cell carcinoma (SCC) is the most common subtype for nasopharyngeal ca, but that non-keratinizing can be subdivided into undifferentiated and differentiated subtypes.

Should histology be 8020 (undifferentiated carcinoma) or 8072 (non-keratinizing SCC)?

The only Other Sites H Rule related to extramammary Paget disease is included in the Multiple Tumors Abstracted as a Single Primary module. Rule H28 instructs one to code the histology of the underlying tumor when there is extramammary Paget disease and an underlying tumor of the anus, perianal region, or vulva. Therefore, a vulvar extramammary Paget disease with underlying adenocarcinoma is coded as adenocarcinoma (8140/3), and not extramammary Paget disease (8542/3).

However, there is no M Rule confirming extramammary Paget disease and the underlying adenocarcinoma are a single primary (i.e., multiple tumors abstracted as a single primary) making it difficult for one to use the Multiple Tumors Abstracted as a Single Primary H rules module.

We recognize this is a longstanding histology coding rule, but how are registrars supposed to arrive at Rule H28 when the M Rules must be applied first and do not instruct one to accession a single primary? Moreover, if this is to be a single primary (per rule M2), why is there no H Rule in the Single Tumor module?

Patient was diagnosed March 2023 with a neuroendocrine tumorlet of the rectum measuring 0.8 mm via excisional biopsy during colonoscopy.

Prior SINQ 20160011 (stomach specific) indicates microcarcinoid and carcinoid tumors are reportable. Microcarcinoid is a designation for neuroendocrine tumors of the stomach when they are less than 0.5 cm. in size.

Is the current rectal tumor a reportable gastrointestinal neuroendocrine tumor if it is less than 5 mm (i.e., is a neuroendocrine tumorlet equivalent to a microcarcinoid)?

Patient was diagnosed on imaging with enhancement along the right optic nerve intraorbital segment, displacing the optic nerve, most consistent with optic nerve sheath meningioma.

Extracranial meningiomas are rare, however SINQ 20230052 does contain an exception for reportability in a different head and neck site because it is not an intracranial location.

It is unclear if this portion of the meninges surrounding the intraorbital optic nerve is still “intracranial” and thus reportable.

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).