Inflammatory myofibroblastic tumor with actionable fusion driver: ALK fusion (TPM3-ALK, T...

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

ID	`RF-IMT-HIGH-RISK-BIOLOGY`
Type	Red flag
Status	reviewed 2026-04-27 \| pending_clinical_signoff
Diseases	`DIS-IMT`
Sources	`SRC-NCCN-SARCOMA` `SRC-ONCOKB`

Red Flag Origin

Definition	Inflammatory myofibroblastic tumor with actionable fusion driver: ALK fusion (TPM3-ALK, TPM4-ALK, CLTC-ALK; ~50%), ROS1 fusion (~10%), NTRK fusion (rare), RET fusion (rare), or PDGFRB fusion (rare) — opens targeted-therapy line (crizotinib / lorlatinib for ALK; entrectinib / crizotinib for ROS1; larotrectinib / entrectinib for NTRK; selpercatinib for RET) sparing the patient cytotoxic chemotherapy and aggressive surgery for unresectable disease.
Clinical direction	intensify
Category	high-risk-biology

Trigger Logic

{
  "any_of": [
    {
      "finding": "BIO-ALK-FUSION",
      "value": "positive"
    },
    {
      "finding": "BIO-ALK-REARRANGEMENT",
      "value": "positive"
    },
    {
      "finding": "BIO-ROS1-FUSION",
      "value": "positive"
    },
    {
      "finding": "BIO-NTRK-FUSION",
      "value": "positive"
    },
    {
      "finding": "BIO-RET",
      "value": "fusion"
    }
  ],
  "type": "biomarker"
}

Notes

IMT is fusion-driven in ~60–70% of cases; comprehensive genomic profiling at diagnosis is now standard. Crizotinib in ALK-positive IMT (Schöffski et al, Lancet Oncol 2018; ORR ~50%; pediatric COG- ADVL0912) — also active in ROS1+ (entrectinib STARTRK-2). Resistance to crizotinib emerges via secondary ALK kinase mutations — switch to lorlatinib (more potent, CNS-penetrant) or alectinib. NTRK-fusion IMT responds to larotrectinib / entrectinib (NCCN tumor-agnostic). RET- fusion IMT case reports of selpercatinib responses. This RF re-routes algorithm from surgery-first / chemotherapy to fusion-targeted 1L.

Used By

No reverse references found in the YAML corpus.