SEER Inquiry System - Search

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

ICD-O-3 tells us that perianal skin is C445 and we do not capture basal or squamous cell skin cancers in our registry. The AJCC manual stages perianal skin cancers within 5 cm of the anus with the anus chapter.  We cannot AJCC stage them as an anus if we are not capturing them as C445.  I realize we do not code a site in order to stage. We have been following the reportability rules and not capturing. Is this correct? I do not see this addressed in the new Other Sites Solid Tumor Rules.

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?

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 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.

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? 

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)?