SEER Inquiry System - Search

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)?

Since the peripheral nerves are included in the Malignant CNS schema of the Solid Tumor Rules, neither the differences in subsite nor timing indicate these are separate primaries (Rule M10 indicates a single primary). However, these are separate MPNSTs in different sites and the tumors are not stated to be metastasis. Additionally, these are treated as separate primaries by the managing physician.

While the malignant CNS tumors do not take timing into account, is this correct for these peripheral nerve tumors that are often treated similarly to soft tissue tumors? Should Rule M8 be updated to include tumors in different peripheral nerve subsites?

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?

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.

The patient was not synchronously diagnosed with multiple tumors, but three separate tumors with three different histologies were diagnosed at different times and no more specific histology was provided for the NSCLC. The timing rules do not apply to this case (the tumors were not greater than 3 years apart and they were not synchronously/simultaneously diagnosed).

While NSCLC is a NOS histology for both adenocarcinoma and squamous cell carcinoma, it is unclear if Rule M8 should apply because NSCLC is not listed in Table 3 (Table 3 is not an exhaustive list). In some situations, Rule M8 would apply if the tumors were different histologies and one of the histologies was not listed in the Table. Does that logic still apply if one of the tumors is NSCLC? If NSCLC is excluded from Rule M8, is Rule M14 the appropriate M Rule for the 2022 NSCLC diagnosis?

The AJCC 8th edition confirms that the identification of psammomatous calcifications within a cervical lymph node is metastatic disease.

Example: Patient had a thyroid lobectomy and level VI neck node excision in August 2022. The final diagnosis is multifocal papillary carcinoma of the thyroid, as well as rare psammomatous calcifications only in the resected node. The pathologist notes that “psammoma bodies only” in lymph nodes is not well defined, and while indolent, they do indicate capacity for lymphatic spread and are pN1a.

Should thyroid primaries with cervical node psammomatous calcifications get captured in EOD Regional Nodes category as it is in the AJCC pN staging?