SEER Inquiry System - Search

The 2022 SEER Manual indicates the p16 status (positive or negative) can be used to code more the specific histology for squamous cell carcinoma, human papilloma virus (HPV) positive (8085) and squamous cell carcinoma, HPV negative (8086). However, the histology coding instructions in the Other Sites schema have not been updated and the 2022 SEER Manual does not cover all situations commonly encountered in the registry. Does the clarification regarding p16 apply to these other situations?

1. How is histology coded when the final diagnosis of the most representative specimen is adenocarcinoma (NOS), but the immunohistochemistry is p16 negative? Is this adequate to code histology to 8484/3 (adenocarcinoma, HPV-independent, NOS)? The pathologist did not specifically indicate this was HPV-independent adenocarcinoma, and the clarification in the 2022 SEER Manual does not include this more specific adenocarcinoma histology.
2. How is histology coded when the Pap smear is positive for squamous cell carcinoma, p16 positive, but the most representative specimen from the primary tumor (the subsequent cervix biopsy) is only stated to be squamous cell carcinoma (NOS)? The p16 studies were not repeated on the most representative specimen, and the existing 2007 Multiple Primaries/Histology (MP/H) General Rules indicate to code the histology from the most representative specimen over a cytology report. Following the existing 2007 MPH General Rules, the histology should be 8070 (squamous cell carcinoma, NOS). However, this does not account for the p16 status of the tumor.
3. How is histology coded when a biopsy of a metastasis (e.g., a lymph node metastasis) proved squamous cell carcinoma, p16 negative, but a subsequent biopsy of the primary cervix tumor proved squamous cell carcinoma (NOS) without additional IHC studies? Again, the 2007 MP/H General Rules confirm the primary site specimen should be used to code the histology, resulting in a diagnosis of 8070 (squamous cell carcinoma, NOS), but this ignores the p16 status of the tumor.

In previous STR versions and the ICD-O-3.2, SFT/hemangiopericytoma, WHO G1 is 8815/0 and only SFT/hemangiopericytoma, WHO G2 was 8815/1. However, Table 6 (Non-Malignant CNS, Specific Histologies, NOS, and Subtypes/Variants) was changed in the 2025 updates to indicate both G1 and G2 SFT/hemangiopericytoma are 8815/1.

No date range was provided for this change in the STR and the behavior of this tumor was not updated by the standard setters in other references (i.e., ICD-O-3.2). The behavior of G1 SFT/hemangiopericytoma was not updated in the 2025 ICD-O-3.2 updates. If the ICD-O-3.2 was the source of this change, should this have been documented in the 2025 NAACCR Implementation Guidelines? However, the 2025 NAACCR Implementation Guidelines indicates, "There are no ICD-O-3 changes for 2025." Is this behavior change in 2025 Solid Tumor Rules updates an error? Should the behavior of SFT/hemangiopericytoma, WHO G1 remain /0? 

According to College of American Pathologists (CAP), lobular neoplasia is also known as lobular carcinoma in situ. In a previous SEER question 20041089, it was stated that they were not the same and should not be reported unless it was a Grade 3. I assume this has changed and we are to report lobular neoplasia as lobular carcinoma in situ, is this correct?

VIN II-III was a reportable condition in the past. There was a SINQ note to that effect which is now gone from the system. Would it be better to reactivate that note and put a date reference in it so that there is documentation available to confirm this disease (and other IN II-III diseases) was previously reportable? If the note is not reactivated, could there be some indication in SINQ 20120081 of the prior reportability of this disease process?

First, reportability of clear cell papillary renal cell carcinoma changed from 8323/3 to 8323/1. Although it does not appear the standard-setters implemented this change, note of the conflict between the ICD-O-3.2 and the Solid Tumor Rules (STR) is not included in the Implementation Guidelines or STR. The current Note for clear cell papillary renal cell carcinoma (8323) was left in Table 1, so this presumably is still reportable. It would be helpful if the conflict with ICD-O-3.2 was addressed, especially since the existing Note refers to changes made back in 2016 (not 2018 or 2021).

Second, is the term sarcomatoid renal cell carcinoma still coded as a synonym for renal cell carcinoma (8312) because sarcomatoid is referring to a pattern of differentiation or 8318 (renal cell carcinoma, sarcomatoid)? The STR, Table 1, lists sarcomatoid renal cell carcinoma as 8312, but the ICD-O-3.2 lists this as 8318. The Note in Table 1 still indicates WHO/IARC and College of American Pathologists agree that sarcomatoid carcinoma is a pattern of differentiation, not a specific subtype, of renal cell carcinoma. This appears to conflict with WHO/IARC ICD-O-3.2 Coding Table as it provides a different, specific histology code for this malignancy. How can WHO/IARC classify this both a pattern of renal cell carcinoma and a separate, specific histology?

This question was prompted from preparing SEER*Educate coding exercises. We will use the answer as a reference in the rationales.

Because "evolving" melanoma was never reportable, this issue only relates to "early" melanoma.

Foreskin circumcision shows: Penile intraepithelial neoplasia, differentiated type (differentiated PeIN). If reportable, how would the histology and behavior be coded? Is this behavior /2?