Table 2.

Summary of what radiologists should know about molecular targeted therapies (MTT) in advanced and metastatic non-GIST STS

Imaging findings which indicate response to MTT	Decrease in tumor density
	Decrease in enhancement – By blocking angiogenesis mediated by VEGF or PDGF pathways (TKIs) – By apoptosis or hyalinization: all MTTs
	Decrease in size
	Ancillary findings: hemorrhage, cystic change, transient increase in size
Treatment response criteria	Understand limitations of RECIST
	Alternative criteria: Choi, size and attenuation CT criteria, MASS criteria
Imaging findings indicating tumor recurrence	Increase in size
	Increase in tumor density
	Enhancing intratumoral nodule
Imaging findings of drug toxicity	Fluid retention: anasarca, pleural effusions, pulmonary edema
	Pneumonitis
	Hepatic steatosis, hepatitis
	Acute cholecystitis
	Pancreatitis
	Bowel-related complications: ischemic colitis, pneumatosis intestinalis
	Arterial and venous thromboembolic phenomenon
	Capillary leak syndrome: unilateral pulmonary edema

MTT, molecular targeted therapy; GIST, gastrointestinal stromal tumor; STS, soft tissue sarcoma; VEGF, vascular endothelial growth factor; PDGF, platelet-derived growth factor; TKI, tyrosine kinase inhibitor; RECIST, Response Evaluation Criteria in Solid Tumors; MASS, morphology, attenuation, size and structure.