SEER Inquiry System - Search

The case in question represents an adenocarcinoma with neuroendocrine differentiation that arises in the absence of androgen-deprivation therapy. A 2023 journal article states, “We show that amphicrine prostate cancer is a unique entity and differs in clinical and molecular features from high-grade neuroendocrine carcinomas of the prostate. Our study highlights the need to recognize AMPC as a unique molecularly defined subgroup of prostate cancer.”

Should we be coding this with histology 8140 (Adenocarcinoma, NOS) because we have no specific code for an amphicrine carcinoma? Should we code this as 8045 (Mixed small cell carcinoma) because this is possibly the only way to capture both the adenocarcinoma and neuroendocrine components in a patient without previous treatment?

Our concern about using histology code 8574 (Adenocarcinoma with neuroendocrine differentiation) is that, while a valid histology code, this might confound the data if researchers are trying to separate the truly treatment-related tumors from other histologies captured under 8574.

There was a 3.5 cm invasive adenocarcinoma tumor in the pancreatic head. There were four separate, sized pancreatic neuroendocrine tumors measuring 0.9, 0.7, 0.5 and 0.2 cm in the pancreatic body. There are multiple tumors with distinctly different histologies. However, Table 11 (Pancreas Histologies) does not include any entries for neuroendocrine tumors of the pancreas (e.g., pancreatic NET, WHO grade 1, histology 8240). While it would seem Rule M19 should apply as they’re distinctly different histologies, because PanNETs are not included in Table 11, it is not clear which M Rule applies to these multiple tumors.

If Rule M19 does not apply, we are left with Rule M21 (Abstract a single primary when there are multiple tumors that do not meet any of the above criteria). Are these separate tumors with distinctly different histologies really a single primary? Pancreatic neuroendocrine tumors are not an uncommon histology, is there a reason these were not included in Table 11?

Serous borderline tumor–micropapillary variant (8460/2, C569) was included in the ICD-O-3 Behavior Code/term updates effective 1/1/2018 but marked as Not Reportable for 2018.

There have been multiple additional updates to the ICD-O but no further clarification as to the reportability of this histology. ICD-O-3.2 currently lists serous borderline tumor, micropapillary variant (C569) as 8460/2 with no mention of reportability and no information provided in Includes/Excludes.

SINQ 20220032 instructs capturing this histology as reportable when diagnosed 1/1/2021 or later and occurring in the testis. The answer indicates this is reportable due to the /2 behavior code in ICD-O-3.2, but it does not specify that it is limited to specific sites.

Is serous borderline tumor, micropapillary variant reportable for ovary? If so, what dates apply? Is serous borderline tumor, micropapillary variant of the testis diagnosed after 1/1/2021 reportable?

Patient had a total abdominal hysterectomy-bilateral salpingo-oophorectomy performed in January 2023 with final diagnosis of myxoid and epithelioid leiomyosarcoma.

Diagnosis comment states: The tumor is 15 cm per report. It grows in nests and poorly formed interanastomosing trabeculae and cords that are separated by abundant myxoid background. The cells have an epithelioid morphology with eosinophilic cytoplasm, large nuclei, and very prominent nucleoli. The mitotic activity is overall low ranging from 1 to 3/10 HPFs.

Immunohistochemical stains performed at the outside hospital showed diffuse positivity for SMA, desmin, caldesmon, and PR. They are negative for CD10, claudin-4, calretinin, HBM45, MART1 (rare weakly positive cells), PANCK, and SOX10. This immunohistochemical profile supports a smooth muscle derivation of this neoplasm. As this tumor is extensively myxoid, diagnostic criteria differ from the spindle cell leiomyosarcoma.

Per Solid Tumor Rules Other Sites, Table 16: Uterine Corpus Histologies, Epithelioid Leiomyosarcoma (8891/3) and Myxoid Leiomyosarcoma (8896/3) are both subtypes of Sarcoma, NOS (8800/3).  Per Rule H21, use a combination code when there are multiple specific histologies AND the combination is listed in Table 2 OR there are coding instructions for the combination in the applicable histology Tables 3-21 OR you receive a combination code from Ask A SEER Registrar.  Since there is no combination listed in Table 2 and there is no instruction for the combination in Table 16, how should the histology be coded for this tumor?

Lung abnormality on imaging prompted diagnosis on subsequent biopsy and clinical staging was documented as cT1b N0 M0. There was an attempt at resection, but the patient was found to have chest wall involvement and the procedure was aborted.

How would Reason for No Surgery of Primary Site be coded in these types of scenarios when the surgery is aborted and the treatment plan changes due to the extension seen during surgery?

The 10/2023 TURBT final diagnosis is “Urothelial carcinoma with mixed histologic appearances, see synoptic summary below for details.” The synoptic report includes, “Histologic Type Comment: Invasive carcinoma percentages: Micropapillary 60-70%, high grade or poorly differentiated urothelial 20-30%, squamous 10-20%.” The squamous component is stated to be “Urothelial carcinoma with squamous differentiation.”

It appears there are two specific urothelial carcinoma subtypes to consider: Urothelial carcinoma, micropapillary variant (8131/3) and poorly differentiated carcinoma (8020/3). The squamous component would not be considered because there is no specific histology for “squamous differentiation.”

The micropapillary component is the predominant histology (60-70%) in this case, and it does seem like this is important to capture. However, the WHO Blue Book indicates poorly differentiated carcinoma of the bladder has a poor prognosis.

The synoptic report calls this “Invasive adenocarcinoma with secondary Paget disease of anal mucosa and perianal skin.” The tumor size is listed as “2.1 x 1.7 x 0.7 cm, including associated advanced adenoma; size does not include the extent of the associated Paget disease, which extends for at least 2 cm distally.”  Clinically this is called an incidentally discovered Paget’s disease.

It is unclear if this is a collision tumor that should be abstracted as separate primaries, or if this is a single tumor with underlying Paget’s disease (similar to that described in Other Sites Rule H26). If this is a single rectal tumor, there does not appear to be an H rule for this scenario.

This patient had serosal involvement and the pathologist and managing physician staged this as pT4a disease.  This extension seems best captured by EOD Primary Tumor code 500.  Additionally, the patient had discontinuous metastatic involvement of the peritoneum, and this was staged by the pathologist and managing physician as pM1b (Intraperitoneal metastasis only, including peritoneal mucinous deposits containing tumor cells).  Although this peritoneal involvement was present in the right lower quadrant, it was staged as distant metastatic disease and not as part of the primary tumor category. However, currently EOD Primary Tumor code 600 would seem to apply since the peritoneal tumor was in the right lower quadrant.  Code 600 is defined as mucinous tumors with peritoneal involvement confined within right lower quadrant.  This EOD Primary Tumor code and the physician’s M category assignment do not align; the physician has staged this as distant metastasis (M category, not the T category).  Should the peritoneal metastasis (even limited to the right lower quadrant) be included in the EOD Mets field and not in the EOD Primary Tumor field?  In other words, should the peritoneal involvement included in EOD Primary Tumor code 600 be reclassified in EOD Mets code 30 (Intraperitoneal metastasis (peritoneal carcinomatosis) WITH or WITHOUT peritoneal mucinous deposits containing tumor cells)?

The final diagnosis for a left thyroid lobectomy was Papillary thyroid microcarcinoma, further stated to be Histologic Type: Papillary carcinoma, follicular variant, encapsulated/well demarcated, non-invasive. The diagnosis comment states there is a small follicular pattern papillary microcarcinoma.

Is the designation of “non-invasive” for this papillary follicular tumor equivalent to a non-reportable diagnosis of Non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), 8349/1? Or should this be accessioned as either a reportable in situ (non-invasive) papillary follicular thyroid carcinoma or a papillary microcarcinoma per the diagnosis comment?

Disease History

2018 - Lymphomatoid papulosis (non-reportable)

2020 - Transform to CTCL (and called Mycosis Fungoides specifically) (CTCL/MF same primary)

2021 - Transform to CTCL with large cell transformation