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Innovative Medicines & Omics Subdural hematoma associated with avapritinib

Figure 1. Role of receptors in the activation of signaling pathways in gastrointestinal stromal tumors. Reproduced from Vallilas et al. 4
Abbreviations: RTK: Receptor tyrosine kinase; PDGFRA: Platelet-derived growth factor receptor a; c-Kit: Cellular Kit; VEGFR: Vascular endothelial
growth factor receptor; RAF: Rapidly accelerated fibrosarcoma; MEK: Mitogen-activated protein kinase kinase; ERK ½: Extracellular signal-regulated
kinase 1 and 2; PI3K: Phosphoinositide 3-kinase; AKT: Protein kinase b; mTOR: Mechanistic target of Rapamycin; Src: Sarcoma; FAK: Focal adhesion
kinase.
hepatic encephalopathy, endocrine emergencies (hyper/
hypothyroidism and adrenal insufficiency), seizures, and
trauma were considered less likely.
Head CT (Figure 2) revealed a large SDH (up to 18 mm
thick) overlying the left cerebral convexity, resulting in
a 15-mm left-to-right shunt of midline structures and
a trapped/dilated right lateral ventricle. Global sulcal
effacement and uncal herniation with mild mass effect
on the brainstem were noted. No evidence of a large
transcortical infarct or acute bony abnormality was found.
In the abdominal/pelvic examination, similar-appearing
liver metastases and small nodules or lymph nodes in the
lower mesentery were detected. No bowel obstruction,
abscess, free gas, diverticulitis, or appendicitis was noted.
Scattered sclerotic skeletal lesions indicated metastasis. Figure 2. Non-contrasted computed tomography of the head showing left
After CT, the neurosurgeon was consulted, and subdural hematoma, with rightward midline shift and enlargement of the
right ventricular system, and effacement of ambient cisterns with uncal
following a detailed discussion, the patient expressed herniation.
verbal understanding, consented, and wished to proceed
with a left burr hole washout (Figure 3). After the removal was discharged in a stable clinical condition. Oncology
of the left scalp JP drain, the patient was cleared for recommended discontinuing the current chemotherapy
discharge by neurosurgery to follow-up with them in (Avapritinib) because of the recent SDH development.
2 weeks with head CT. Acute metabolic encephalopathy This is reported as a severe and infrequent side effect of
secondary to SDH significantly improved, and the patient avapritnib. Avapritinib was not resumed, and the patient

Volume 2 Issue 1 (2025) 95 doi: 10.36922/imo.7068