CSF1R expression / CSF1R pathway activation (TGCT)

Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.

ID	`BIO-CSF1R`
Type	Biomarker
Aliases	CSF1R (Colony-Stimulating Factor 1 Receptor)Експресія CSF1R / активація шляху CSF1R (ТГКП)
Status	reviewed 2026-05-04 \| pending_clinical_signoff
Diseases	None declared
Sources	`SRC-ILLUMINATE-TAP-2019` `SRC-NCCN-SARCOMA`

Biomarker Facts

Biomarker type	gene_expression
Mutation details	{"functional_impact": "activating", "gene": "CSF1R", "variant_type": "overexpression / pathway activation"}
Measurement	MethodIHC (CSF1R expression on macrophage/giant cell population); molecular: COL6A3-CSF1 fusion by RNA-seq (~50% of diffuse TGCT)
Actionability lookup	{"gene": "CSF1R", "variant": "overexpression"}
Related biomarkers	None declared

Notes

CSF1R (CD115) is the receptor for colony-stimulating factor 1 (CSF1/M-CSF) and IL-34. In TGCT (diffuse type, formerly PVNS), the predominant mechanism is CSF1 overexpression by a minority neoplastic cell population (via COL6A3-CSF1 fusion in ~50%), which recruits and drives proliferation of CSF1R-expressing macrophages and osteoclast-like giant cells constituting the bulk of the tumor mass. Pexidartinib (PLX3397) is a CSF1R/KIT/FLT3 inhibitor FDA-approved (2019) specifically for TGCT. CSF1R is also expressed broadly on tumor-associated macrophages (TAMs) — multiple investigational agents target TAMs via CSF1R (emactuzumab, cabiralizumab) but none is approved for non-TGCT indications. Do not confuse with KIT (CD117) — pexidartinib inhibits both, but the TGCT approval is CSF1R pathway-driven.

Used By

Actionability

BMA-CSF1R-TGCT - Pexidartinib (PLX3397), a CSF1R/KIT/FLT3 inhibitor, is FDA-approved (August 2019) for adu...

Diseases

DIS-TGCT - Tenosynovial giant cell tumor (TGCT)

Indications

IND-TGCT-1L-PEXIDARTINIB - IND-TGCT-1L-PEXIDARTINIB