SEER Inquiry System - Search

For cases diagnosed 2025 and later: Assign behavior /1 for solitary fibrous tumor unless stated to be malignant.

A review by the Cancer PathCHART expert neuropathologists found behavior code /0 is incorrect and both solitary fibrous tumor grade 1 and grade 2 are coded as 8815/1. WHO Classification of Central Nervous System Tumors, 5th edition, assigns behavior as /1 and no longer recommends terms solitary fibrous tumor/hemagiopericytoma and hemagiopericytoma. The STR table is correct. Future updates to ICD-O should reflect this behavior.

WHO Classification of Tumours, Central Nervous System Tumours, 5th ed. was reviewed by the CPC expert pathologists for implementation for cases diagnosed January 1, 2025. 

Reminder: Comparing the CPC Validity Status included in the 2024 CPC*Search to that included in the 2025 SMVL (that table that drives the edits) is incorrect. CNS Tumors were not reviewed for 2024 implementation, they were reviewed for 2025 implementation. There will be a 2025 CPC*Search and a /1 will be designated as a Valid.   

Do not assign a behavior code of /2 to these cases unless you have a way to flag them so that they are not reported to the standard setters as in situ cases. Work with your state central registry to ensure that these cases are not unintentionally included in state case submission.

Do not report superficial CD34-positive fibroblastic tumor (8810/1) of the thigh.

WHO Classification of Soft Tissue and Bone Tumors, 5th ed., defines superficial CD34-positive fibroblastic tumor as a distinctive low-grade neoplasm of the skin and subcutis, most frequently occurring in the lower extremities, especially thigh, followed by arm, buttock, shoulder, and rarely, vulva.

Assign Code 3 (Positive histology PLUS positive immunophenotyping or genetic testing) for

1. Cases with positive histology for the neoplasm being abstracted (including acceptable ambiguous terminology and provisional diagnosis), AND 

• Immunophenotyping, genetic testing, or JAK2 is listed in the Definitive Diagnosis in the Heme Database, AND
• Testing
  • Confirms the neoplasm OR
  • Identifies a more specific histology (not preceded by ambiguous terminology)
  • Peripheral blood smear followed by flow cytometry (most commonly done with CLL/SLL, 9823/3)

2. A not otherwise specified (NOS) histology diagnosed and not a provisional diagnosis, AND genetic/immunophenotyping was performed and positive

Refer to the current version of the Heme Manual for specific notes and examples when coding Diagnostic Confirmation.

Do not include the disease in the sequencing if the original hematolymphoid disease was not reportable at time of diagnosis.

The 2025 SEER Manual Sequence Number--Central Coding Instruction 1.a advises: A ‘reportable’ primary refers to the site/histology/behavior of the tumor and the years when reporting was required. Review of the reportability requirements in effect during the diagnosis year will be needed.

Without evidence of a new testicular tumor, record this as a single primary now with metastatic disease (seminoma). The seminoma may not have been identified in the original tumor and treatment was based on the histologies found. This allowed the seminoma to metastasize.

Code meningioma, NOS (9530/0) based on the integrated diagnosis and histological classification. WHO Classification of Central Nervous System Tumors, 5th edition, states that brain invasion is a criterion for the diagnosis of CNS WHO grade 2 meningioma, and there is no statement of brain invasion, atypical meningioma, or other WHO grade 2 lesions. WHO has not proposed behavior codes based on WHO grade alone.

Do not code as a treatment. Record the cessation of immunosuppressive drug treatment in text to explain the patient’s change in disease status.

Report LR-M unless there is information to the contrary. The American College of Radiology defines LR-M as "probably or definitely malignant, not necessarily hepatocellular carcinoma (HCC)."