SEER Inquiry System - Search

Example: Patient is diagnosed with grade 1 well-differentiated neuroendocrine tumor of the ileum, confirmed on ileocolic resection in 2023. The final diagnosis is a 2.8 cm ileal mass, with focal lymph-vascular invasion and a single 0.6 cm tumor deposit within mesenteric fat; primary tumor completely resected with widely negative margins and 10 regional nodes negative for malignancy.

According to AJCC, mesenteric masses less than 2 cm should be stated in the pathology report as being present and collected by registrars but do not affect stage. EOD Regional Nodes has a code for large mesenteric masses greater than 2 cm only. How should we record these smaller tumor deposits if they are not supposed to affect stage?

1) In the SEER Manual's code definitions for Neoadjuvant Therapy - Treatment Effect, some sites specify the percentage of viable tumor. Pathology reports often list this along with the percentage of necrosis (e.g., 10% necrosis and 90% viable tumor). If only the percent necrosis is stated, is it acceptable to infer the percent viable tumor? For example, pathology report states only "treatment effect: present, necrosis extent: 30%" - could we then deduce that the percent viable tumor in this case would be 70%?

2) Can statements of Residual Cancer Burden (RCB) Class be used?  For example, pathology report states Treatment Effect: Residual Cancer Burden Class II, with no further description of partial vs. complete response. It appears that RCB Class II is a "moderate burden" of residual tumor after neoadjuvant therapy; could this be interpreted as a partial response in the Neoadjuvant Therapy--Treatment Effect code definitions?

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?

The resection pathology report final diagnosis indicates this is both mixed mucinous and non-mucinous with a lepidic predominant component. The pathologist notes this is “Lepidic: 75%. Acinar: 25%.”  The percentage of the mucinous component is not documented.

Rule H1, Note 1, states “When mucinous carcinoma is mixed with another histology, such as adenocarcinoma and mucinous carcinoma, code mucinous ONLY when mucinous is documented to be greater than 50% of the tumor.” While mixed invasive mucinous and non-mucinous carcinoma is included in Table 2 (Combination/Mixed Histology Codes) without a required percentage, it is unclear whether one should move past Rule H7 and use Rule H8 to code this combination histology code. Rule H7 would instruct one to code the histology to lepidic adenocarcinoma (adenocarcinoma, lepidic predominant) based on the percentage of the lepidic component in the tumor. However, this does not address the mixed mucinous and non-mucinous diagnosis. Which H Rule and histology apply to this case?

The final diagnosis on bone marrow biopsy was high grade myeloid stem cell neoplasm, 17% blasts by differential count.  The pathologist further states that this could be classified as “MDS with increased blasts (MDS-IB2) per the WHO 5th edition classification, or MDS/AML per the international consensus classification (ICC).”  FISH and cytogenetics revealed a loss of 7q, but no other AML-related genetic abnormalities. The physician confirms the patient has MDS/AML.

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?

Previous SINQ 20091100 has a similar scenario and the instruction was to code as lentigo maligna (8742/2); however, it does not appear to be applicable to cases diagnosed after 2020.

The WHO Blue Book does not list melanoma, lentiginous type or lentiginous melanoma in situ as an alternate term for lentigo maligna and neither do the STR or the ICD-O-3.2.

Small cell carcinoma is a specific type of neuroendocrine carcinoma for the lung. However, Table 3 lists neuroendocrine carcinoma, NOS as the more specific subtype/variant in Column 3.

Using Lung Solid Tumor Rules, Rule H6, a diagnosis of poorly differentiated neuroendocrine carcinoma (small cell carcinoma)” would be coded as 8246, instead of 8041, because there are two histologies under consideration (an NOS and a subtype/variant in Table 3), and the rule tells us to code the subtype/variant. However, small cell carcinoma is more specific than the NOS diagnosis (neuroendocrine carcinoma, NOS). Should Table 3 be updated to reflect which histology is the NOS and which is the more specific?

In 2021, the patient was diagnosed with a non-reportable appendiceal LAMN.  Resection showed a tumor diffusely involving the appendix and perforating the visceral peritoneum, as well as extensive intraperitoneal metastasis.  In 2023, a lung wedge resection revealed metastatic mucinous neoplasm involving lung parenchyma and pleura, consistent with metastasis of the known appendiceal primary.  It is understood that intraperitoneal spread of an appendiceal LAMN does not make it reportable because the peritoneal disease is also non-invasive.  Does extraperitoneal metastasis of an appendiceal LAMN diagnosed prior to 2022 make it invasive disease and therefore reportable?