Reportability/Histology: Is a diagnosis of non-lung neuroendocrine tumorlet reportable? See Discussion.
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)?
Do not report neuroendocrine tumorlet of lung and non-lung sites. Microcarcinoid and carcinoid tumors are reportable.
Tumorlet is a tumor of neuroendocrine differentiation, defined by size < 5 mm in diameter, mitotic count < 2 mitoses/2 mm², and absence of necrosis. Microcarcinoid is a designation for neuroendocrine tumors when they are less than 0.5 cm. in size. The term "tumorlet" is used in a number of other settings, referring to small tumors (usually < 0.5 cm), and does not necessarily mean carcinoid tumor.
The term microcarcinoid tumor is not equivalent to neuroendocrine tumorlet.
Solid Tumor Rules/Histology--Ovary: How is histology coded for an ovary case with a diagnosis of “high grade papillary serous carcinoma” in 2023? This term is not in the Solid Tumor Rules and ICD-O 3.2 updates. Is “high grade papillary serous carcinoma” equivalent to “high grade serous carcinoma” (8461) or to “papillary serous adenocarcinoma” (8441) with high grade captured only in the Grade fields, or is there another more appropriate code?
Assign code 8461/3 for high-grade papillary serous carcinoma.
Solid Tumor Rules/Histology--Breast: Is ductal carcinoma in situ (DCIS), solid type coded as 8500/2 or 8230/2? See Discussion.
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?
Assign 8230/2 (ductal carcinoma in situ, solid type/intraductal carcinoma, solid type) using Breast Solid Tumor Rules Table 3 as instructed in Rule H2 for in situ tumors. The carcinoma, NST row lists this histology in the subtype/variant column 3.
Coding histology for in situ breast tumor differs from invasive. While the majority of in situ breast primaries will be coded to DCIS 8500/2, there are others that are listed in Table 3 that should be coded according to the specific histology. Some codes have the word subtype or type as part of their histologic term so these can be coded based on the histologic term as listed in the table. We suggest you routinely review the histology tables to see if a term is listed.
Solid Tumor Rules--Urinary: The example used in Rule M15 of the Urinary Solid Tumor Rules refers to the same row in Table 3. Should the example say Table 2 since Table 3 is non-reportable urinary tumors. See Discussion.
Rule M15
Abstract a single primary when synchronous, separate/non-contiguous tumors are on the same row in Table 2 in the Equivalent Terms and Definitions.
Note: The same row means the tumors are
• The same histology (same four-digit ICD-O code) OR
• One is the preferred term (column 1) and the other is a synonym for the preferred term (column 2) OR
• A NOS (column 1/column 2) and the other is a subtype/variant of that NOS (column 3) OR
• A NOS histology in column 3 with an indented subtype/variant
Example: TURBT shows invasive papillary urothelial carcinoma 8130/3 and CIS/in situ urothelial carcinoma 8120/2. Abstract a single primary. Papillary urothelial carcinoma and urothelial carcinoma are on the same row in Table 3.
The example used in Rule M15 of the Urinary Solid Tumor Rules should refer to Table 2. We will update this in the next revision of the Rules.
Solid Tumor Rules/Histology--Oropharynx: How is histology coded for a 2024 squamous cell carcinoma of the tonsil when immunohistochemistry (IHC) stains are negative for p16, but in situ hybridization (ISH) testing is positive for human papilloma virus (HPV)? See Discussion.
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?
Assign histology as squamous cell carcinoma, HPV positive (8085) for tonsil, NOS (C099) based on the positive HPV test. Codes 8085 and 8086 are valid for a select group of sites. The histology terms and codes that are valid for head and neck sites are included in the Head and Neck Solid Tumor Rules, Table 5 (oropharynx).
HPV detection tests that are used to identify HPV include DNA polymerase chain reaction (PCR), p16 (IHC), or DNA/RNA in situ hybridization. Assign the appropriate method of detection in the SEER data item, SEER Site-Specific Factor 1.
Schema Discriminator 2 captures additional information needed to generate AJCC ID and Schema ID for some anatomic sites as stated in the SSDI Manual. For oropharyngeal cancer, a schema discriminator is used to discriminate between oropharyngeal tumors that are p16 positive, p16 negative, or p16 status unknown in order to assign the appropriate schema ID. Only the HPV p16 test can be used to assign Schema Discriminator 2. If another HPV test is performed, code 9. Override the edit for Schema Discriminator 2 when p16 is negative. Coding updates will be implemented in 2025.