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?

Additional comments in this pathology report state "The entire case was sent in consultation to an ophthalmic pathologist. [Pathologist] assigns a conjunctival melanocytic intraepithelial neoplasia (C-MIN) score of 2-3 due to the upward pagetoid migration of small, dendritic melanocytes. A C-MIN score of 2-3 is between low-grade conjunctival melanocytic intraepithelial lesion (LG-CMIL; C-MIN 2) and high-grade conjunctival intraepithelial lesion (HG-CMIL; C-MIN 3). The older terminology for this lesion would be primary acquired melanosis (PAM) with mild to focally moderate atypia."

This term does not appear in the SEER Program Coding and Staging Manual (SPCSM), Appendix E1 of the SPCSM, or Solid Tumor Rules (specifically rule H3) . 

2012 Total abdominal hysterectomy - bilateral salpingo-oophorectomy

Primary Site – Ovary, Right

Histology - Small-Cell Carcinoma (Hypercalcemic Type), Large-Cell Variant

2024 Total abdominal hysterectomy - bilateral salpingo-oophorectomy

Primary Site – Ovary, Left

Histology - Small-Cell Carcinoma (Hypercalcemic Type), Large-Cell Variant

Malignant Central Nervous System (CNS) Rule M5 instructs us to abstract a single primary (as malignant) when a single tumor is originally diagnosed as non-malignant, the “First course treatment was active surveillance (no tumor resection),” and the subsequent resection pathology is malignant.

This patient’s first course of treatment was not active surveillance. While the patient did not have first course tumor resection, the tumor was treated with Cabergoline.

Should Rule M5 apply because there was no tumor resection? If so, should Rule M5 clearly state no tumor resection is the criteria (not active surveillance)?

SINQ 20230023 does indicate a PitNET diagnosis following a diagnosis of pituitary adenoma does not fall into standard rules, but in the previous SINQ the first course treatment was a partial resection.

It is unclear whether other types of treatment could result in a new malignant PitNET, following a previously treated non-malignant pituitary tumor.

We included this histology in SEER Workshop Case 12 and the histology coding accuracy was less than 40%. From emails we received, it is clear that registrars are unaware that the "somatic type malignancy" can vary but code 9084 applies when the diagnosis is teratoma WITH any non-germ cell tumor component. It may be helpful to add a definition for "teratoma with somatic-type malignancy" (9084) to the Solid Tumor Manual.

SEER Program Coding and Staging Manual indicates high grade dysplasia of esophagus, stomach, and small intestine are reportable. The ICD-O-3.2 does not include “high grade dysplasia” as equivalent to “high grade squamous dysplasia.”

If reportable, would high grade dysplasia (NOS) that originates in the stomach and small intestine default to 8148/2, while esophageal high grade dysplasia (NOS) default to 8077/2?

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).

For example, a chest computed tomography showed multiple subsolid and ground glass pulmonary nodules measuring up to 6 mm; findings favored to reflect adenocarcinoma spectrum lesions.  A literature search seems to indicate that adenocarcinoma spectrum lesions include atypical adenomatous hyperplasia through invasive adenocarcinomas.

Patient underwent excision of an oropharyngeal soft tissue mass revealing plasma cell neoplasm with extensive amyloid deposition. During work-up, bone marrow biopsy also revealed involvement by plasma cell neoplasm, with 5-10% of marrow cellularity. No amyloid seen in bone marrow. Patient was referred for radiation of the oropharyngeal mass. Per medical oncology qualifying best for the diagnosis of solitary extramedullary plasmacytoma with minimal marrow involvement. Decision made for observation by medical oncology in view of “minimal” bone marrow involvement. Question: Is rule M11 correct, and I abstract this case as a plasma cell myeloma, 9732/3, C421?

Patient was diagnosed with essential thrombocytosis 9962/1 or 3 in 1998 (depending if ET was reportable in 1998), treated with Hydrea.

11-17-2022 Blood smear: CALR + myeloproliferative neoplasm, Most Consistent with Primary Myelofibrosis 9961/3 (Noted CALR and ASXL1 mutations).

The following abstractor note from 9661/3 is confusing: A diagnosis of "post essential thrombocythemia myelofibrosis" is a progression of essential thrombocythemia and would be the same primary.