fig4

Figure 4. 36-year-old female with stage IV leiomyosarcoma. Axial (A) T1-weighted, (B) T2-weighted fat-suppressed, and (C) T1-weighted fat-suppressed gadolinium-enhanced MR images of the pelvis show a low T1 signal intensity, high T2 signal intensity, enhancing lesion in the left gluteus maximus detected during routine imaging surveillance, consistent with metastatic disease (*). No other lesions were detected. The patient was asymptomatic from this lesion and presented for cryoablation of presumed oligometastatic disease. (D) Axial CT image during cryoablation of the left gluteus maximus lesion shows a cryoablation probe inserted into the lesion (solid arrow). The ovoid low attenuation ablation zone is visible (arrowheads) and covers the entire lesion with an approximately 1 cm margin. Because of close proximity of the ablation zone to the skin surface, a spinal needle was inserted into the subcutaneous tissues superficial to the lesion (dotted arrow), and hydrodisplacement was performed to displace the skin away from the lesion and the ablation zone (yellow *).