SEER Inquiry System - Search

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.

Histology code 8255/3 best identifies this histology. Complex glands in lung tumors are often associated with a poor prognosis and represent a high-grade pattern in lung cancer grading systems. This histology is not currently recognized as a variant by WHO. 

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.

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 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.

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.   

Report the case when the differential diagnosis includes only reportable neoplasms in the absence of additional information. We are unable to provide general instructions for provisional diagnoses as each situation will need to be reviewed and assessed individually when no further work-up information is available.

Assign myeloid leukemia, NOS (9860/3) to the case described in the example. Assign a generic histology code because a specific histology code cannot be assigned when there are several differential diagnoses. Since the differential diagnoses include a chronic and an acute leukemia, code as myeloid leukemia, NOS since it is not clear if this is chronic or acute.

Do not use the NME size from magnetic resonance imaging (MRI) to code tumor size when both tumor size and NME size are stated or if NME is the only size available. The size of the solid tumor mass takes priority over the size of the NME when provided separately and the NME is larger.

The American College of Radiology, Breast Imaging Reporting and Data System (BI-RADS) defines NME as an area of enhancement on MRI that does not belong to a 3D mass or have distinct features of a mass. It is a separate descriptor from size that includes modifiers describing enhancement patterns with a specific MRI pattern.

Assign 8020/3 for SMARCA4- deficient malignant neoplasms of the esophagus.

The WHO Classification of Digestive System Tumors, 5th edition, lists undifferentiated carcinoma as 8020/3. Undifferentiated carcinoma of the esophagus is characterized by the frequent loss of SMARCA4 or SMARCA2 by immunohistochemistry.

SINQ 20200057 was updated in August 2025 and assigns code 8044/3 for Thoracic SMARCA4-deficient undifferentiated tumor (SMARCA4-UT). The 2025 Solid Tumor Manual includes SMARCA4-deficient or SMARCB1-deficient tumors for thoracic and sinonasal sites (8044/3).

Assigning histology to other individual sites should be on a case-by-case basis.