Soft-tissue Cryoablation in Diffuse Locations: Feasibility and Intermediate Term Outcomes

Purpose: To assess whether diverse tumor location(s) show differences in percutaneous cryoablation (PCA) outcomes of cancer control, morbidity, and ablation volume reduction for many soft-tissue tumor types.

Materials And Methods: A total of 220 computed tomography (CT)- and/or ultrasonography-guided percutaneous cryotherapy procedures were performed for 251 oligometastatic tumors from multiple primary cancers in 126 patients. Tumor location was grouped according to regional sites: retroperitoneal, superficial, intraperitoneal, bone, and head and neck. PCA complications were graded according to Common Terminology Criteria for Adverse Events (version 4.0). Local tumor recurrence and involution were calculated from ablation zone measurements, grouped into 1-, 3-, 6-, 12-, 18-, and 24-month (or later) statistical bins.

Results: Tumor and procedure numbers for each site were 75 and 69 retroperitoneal, 76 and 62 superficial, 39 and 32 intraperitoneal, 34 and 34 bone, and 27 and 26 head and neck. Average diameters of tumor and visible ice during ablation were 3.4 and 5.5 cm, respectively. Major complications (ie, grade >3) attributable to PCA occurred after five procedures (2.3%). At 11 months average follow-up (range, 0-82 mo), a 10% total recurrence rate (26 of 251) was noted; three occurred within the ablation zone, for a local progression rate of 1.2%. Average time to recurrence was 4.9 months, and, at 21 months, the initial ablation zone had reduced in volume by 93%.

Conclusions: CT-guided PCA is a broadly safe, effective local cancer control option for oligometastatic disease with soft-tissue tumors in most anatomic sites. Other than bowel and nerve proximity, PCA also shows good healing if proper visualization and precautions are followed.