SEER Inquiry System - Search

The term “poorly differentiated carcinoma (NOS)” is listed as related to “undifferentiated carcinoma (NOS)” in the ICD-O 3.2. It is also listed in the Solid Tumor Rules for Urinary Table 2 (Urinary subtypes), Other Sites Table 16 (uterine corpus primaries) and Table 19 (vulvar primaries).

Are these the only sites in which one should code “poorly differentiated carcinoma (NOS)” as 8020 (undifferentiated carcinoma)?

How is histology coded if the only microscopic confirmation is from a metastatic site showing “poorly differentiated carcinoma” (NOS) or “invasive carcinoma, poorly differentiated” (NOS)?

Example 1: Primary pancreatic cancer diagnosed on imaging and confirmed with liver mets core biopsy showing “poorly differentiated carcinoma.” Immunostaining pattern was non-specific. No further workup or treatment was planned.

Other Sites - Table 11 (Pancreas Histologies) includes undifferentiated carcinoma (8020/3) as a valid histology; however, the synonyms/subtypes/variants do not mention poorly differentiated carcinoma. How should histology be coded for this case?

Example 2: Hemicolectomy with cecal tumor final diagnosis of “invasive carcinoma, poorly differentiated” and synoptic summary listing “Histologic type: Invasive carcinoma. Histologic grade: G3 of 4: poorly differentiated.”

Colorectal Table 1 (Specific Histologies and Subtypes/Variants) includes undifferentiated adenocarcinoma/carcinoma 8020 as a subtype of adenocarcinoma NOS. There is no mention of poorly differentiated in this context. How should histology be coded for this case?

Patient was diagnosed in July 2022 with biopsy confirmed left kidney renal cell carcinoma. Initially, partial nephrectomy was planned for February 2023 but canceled at the last moment due to the patient’s “history of narcotic use.” The details of that cancellation were otherwise unclear. It appears the treatment plan was changed due to patient non-compliance.

Patient then had cryoablation of the tumor in May of 2023. Subsequent imaging in October found residual tumor, but no disease progression was noted. Again, additional ablation was offered but patient decided on surgical treatment which did not occur until December 2023.

Is the cryoablation second course due to a change of plan if there is no disease progression, recurrence, or treatment failure?

If the cryoablation is first course treatment, then would the partial resection also be first course treatment because it was documented as the treatment plan?

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 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?

The 11/2023 lower gum tumor is a separate tumor occurring after a disease-free interval, so we know the Head and Neck Multiple Tumors Module applies. However, our staff is having difficulty applying the rules to this particular scenario with consistent results.

Is the 11/2023 SCC a non-reportable recurrence per M12, since M4 is ignored due to patient’s prior 2017 C031 (lower gum) primary, and then M6 is ignored due to patient’s prior 05/2022 C023 primary?

Or is the 11/2023 SCC a new primary per M4, since the last diagnosis was in a site differing at the third character (C03 vs C02)? If M4 does not apply due to patient's previous C03 primary, then does M6 apply since it has been more than 5 years since the previous C03 primary?

The 2022 ICD-O-3.2 Implementation Guidelines indicate “Tubulovillous adenoma, high grade” is 8263/2 and is not SEER reportable. However, the 2024 SEER Manual and clarification from recent SINQs (20240021 and 20240025) confirm high grade dysplasia in the esophagus, stomach, and small intestine is reportable (8148/2).

Which reportability reference applies to a diagnosis of a tubulovillous adenoma with high grade dysplasia in non-colorectal sites?

The WHO Classification of Hematopoietic Tumors (Blue Book), 5th edition states: “Rare cases of classic follicular lymphoma with cytological features of follicular lymphoma (FL) grade 3A can present with a prominent diffuse pattern. In the previous edition, such cases were defined as diffuse large B-cell lymphoma (DLBCL). Currently, it is uncertain whether such cases should be classified as FL or diffuse large B-cell lymphoma; and in such cases, individual treatment choices should be made in multidisciplinary conference settings taking into consideration clinical, laboratory, and imaging parameters. The presence of diffuse areas composed entirely or predominantly of large cells, however, warrants a diagnosis of diffuse large B-cell lymphoma.”

Our concern is that the Hematopoietic (Heme) Manual and Database do not provide instruction for coding this scenario. We hesitate to interpret the terms “equivalent to” as ambiguous because one could argue it is unambiguous. Barring this argument, the M and H rules would indicate this is a diagnosis of diffuse large B-cell lymphoma. However, the physician does not seem to agree with the pathologist.

We know that physician TNM staging is not always accurate, and we also know that doctors sometimes use information in assigning their TNM which may not be available to registrars. Is it a discrepancy when the documentation in the chart is unclear or not definitive, yet the physician assigns a TNM that seems to incorporate that documentation? Or is a discrepancy an obvious conflict between chart documentation and the doctor’s staging – such as a mis-assignment of TNM category that doesn’t at all match with clear and complete medical record documentation, or the physician’s use of criteria that should be excluded from the TNM assignment per AJCC guidelines?

A real case example is a patient with breast carcinoma, imaging states 12 cm tumor with thickening of dermis, and thickening of morphologically suspicious internal mammary and level 1-2 axillary lymph nodes. Medical oncologist states locally advanced breast cancer with extensive changes involving skin thickening associated with the mass, at least stage IIIC based on imaging and exam findings, cT4 N3b. Only axillary nodes were sampled and found to be positive. Post-neoadjuvant therapy resection showed only focal DCIS. Per EOD guidelines, would the oncologist’s staging be a discrepancy with the chart documentation and therefore ignored, with EOD-Primary Tumor coded 200 for skin thickening, and EOD-Lymph Nodes 200 for involvement of axillary nodes only? Or would the doctor’s TNM be a clarification/confirmation of documentation terms that we otherwise would not code, with EOD-PT coded 400 for extensive skin involvement and EOD-LNs 600 for internal mammary + axillary nodes?