Reportability--Skin: Is malignant proliferative trichilemmal tumor (PTT) reportable, and if so, do we apply the matrix rule and code it to 8103/3? A literature search reveals these do exist, but are extremely rare.
Malignant PTT (8103/3) of the skin is not reportable. A neoplasm originating in the skin with histology coded to 8103 is not reportable. See 1.b.i. on page 7 in the 2018 SEER manual for a complete list, https://seer.cancer.gov/manuals/2018/SPCSM_2018_maindoc.pdf
Primary Site--Soft Tissue: How is the primary site coded for a PNET found in the groin when the Tumor Board states the primary is unknown but the SEER site/histology validation table does not allow a site of C809 or C76x to be coded in combination with the histology of 9473/3?
Code site to C495 [connective tissue of pelvis, groin].
This was not called metastatic PNET and no other site of disease is noted. PNET is a broad classification of a group of tumors that usually occur in the CNS and can also occur in soft tissue (neuroblastoma, extra-osseous Ewing sarcoma).
Histology--Pancreas: What is the correct code for "non-secretory pancreatic endocrine tumor" with positive lymph nodes on excision indicating a malignant tumor? Pathologist indicated it was not an exocrine tumor.
Code as islet cell carcinoma [8150/3].
There are several cell types in the islets, and each produces a different hormone. The custom has been to name the tumors by their hormone production e.g. insulinoma, glucagonoma, etc. Occasional tumors do not produce any hormone (at least one that can be determined or measured). These tumors are called non-functioning endocrine tumors. Most of the endocrine tumors in the pancreas are islet cell tumors.
EOD-Clinical Extension--Prostate: In the SEER EOD manual, there is a list of terms to distinguish apparent from inapparent tumor for prostate primaries. If a physician uses a term not currently on the list or if a physician uses a list in the "maybe" category, should we assume the tumor to be clinically inapparent or clinically apparent tumor?
For cases diagnosed 1998-2003:
If the physician used a term not on the clinically apparent/inapparent list, ignore that term and use the best information available from other sources to code the EOD-Extension field.
If clarifying stage information is missing and the term is in the maybe category or the term is not on the list, then code EOD-Extension as 30 [localized, NOS] for cases that appear localized.
Reportability/Histology--Soft Tissue: Is atypical spindle cell neoplasm, primitive myxoid mesenchymal tumor of infancy (PMMTI) from the soft tissue of the leg in August of 2019, reportable?
Primitive myxoid mesenchymal tumor of infancy (PMMTI) is reportable. PMMTI is listed in the new WHO 5th edition Classification of Soft Tissue and Bone Tumors under round cell sarcomas. This is a variant of BCOR sarcomas. There is a new ICD-O histology code assigned for cases diagnosed in 2022 or later (9368/3). Code this 2019 case to round cell sarcoma, undifferentiated 8803/3. Use text fields to explain the details.
First Course of Therapy/Hormone Therapy--Meningioma: Should Sandostatin be coded as treatment for a Grade 1 meningioma? Patient had surgery and was somatostatin receptor 2 (SSTR2) positive by immunohistochemistry.
Code Sandostatin (octreotide acetate) as hormonal therapy when given including:
· SSTR 2 positive meningioma (NCCN, 2025: smaller studies support the use of targeted therapy including somatostatin)
· Neuroendocrine tumor (NET) (NCCN, 2025: Tumor control: antitumor effect is supported by studies for well-differentiated G1/G2 gastro-entero-pancreatic NET. In lung/thymic NET, somatostatin analogues may be considered if metastatic or SSTR positive).
The SEER*Rx entry for Octreotide Acetate was updated as studies showed somatostatin analogs may shrink tumors or inhibit further growth.
EOD-Clinical Extension--Prostate: How is this field coded when biopsies of the prostatic apex are positive and the physician clinically stages the case as T1c?
For cases diagnosed 1998-2003:
Code clinical extension to 33 [arising in the prostatic apex] when a biopsy of the prostatic apex is positive for malignancy, with no further evidence of involvement. If biopsies of both the apex and another site within the prostate (for example right lobe) are positive and there is no mention that the malignancy arose in the apex, code extension to 34 [extending into the prostatic apex].
MP/H Rules--Ovary: Rule M7 states bilateral epithelial tumors (8000-8799) are reportable as a single primary. Are bilateral germ cell tumors of the ovary (e.g., dysgerminoma (9060/3)) that occur simultaneously now reported as two primaries?
For cases diagnosed 2007 or later, rule M7 applies to ovarian epithelial tumors with ICD-O-3 histology codes between 8000 and 8799. Rule M7 does not apply to dysgerminoma which is coded to 9060. Go on to the next rule, M8 and abstract as multiple primaries, left and right.
Multiple Primaries/Histology--Lymphoma/Leukemia: How many primaries and what histologies are coded when a path diagnosis for a cervical/neck mass demonstrates classical Hodgkin's lymphoma on a background of chronic lymphocytic leukemia?
For cases diagnosed prior to 1/1/2010:Hodgkin disease and chronic lymphocytic leukemia are separate primaries according to our current instructions. Abstract and code them separately.
For cases diagnosed 1/1/10 and later, refer to the Hematopoietic and Lymphoid Neoplasm Case Reportability and Coding Manual and the Hematopoietic Database (Hematopoietic DB) provided by SEER on its website to research your question. If those resources do not adequately address your issue, submit a new question to SINQ.
CS Extension/CS Lymph Nodes--Lung: How are these fields coded if a lobectomy path specimen indicates that two intrapulmonary lymph nodes are involved by direct extension from the primary tumor?
This answer was provided in the context of CSv1 coding guidelines. The response may not be used after your registry database has been converted to CSv2.Code regional lymph node involvement in CS lymph nodes even when the lymph nodes are involved by direct extension. Do not code direct extension to lymph nodes in CS extension.