Desmoid Cryoablation: A Step-by-Step Poster for Complex Extrabdominal Desmoid Tumors

Selection of patients for desmoid tumor ablation and planning for minimal collateral tissue damage.



Background: Desmoid tumors (DT) are often intractable to chemotherapy with only a 33-37 % success rate on chemo monotherapy {1}. Furthermore, side effects of medical therapy alone may limit treatment course and success. Reports of ongoing severe pain are common for these patients. In the early 2000s, ablations were piloted by IR for better therapeutic outcomes. In the last 10 years, cryoablation for DT has been found the most beneficial method of percutaneous treatment with a 97% partial or complete symptom relief {2}. Many of these tumors are adjacent to sensitive tissues, such as bowel, skin, nerves, and vasculature. In this discussion, we explore a single center approach for protecting these sensitive tissues.

Clinical Findings/Procedure Details:

Ablation procedures are performed primarily with CT guidance, with ultrasound available to assist with probe placement. Cryoablation probes are positioned under imaging guidance, and measurements are performed to ensure adequate lesion coverage. After probes are positioned, multiple different techniques are utilized to protect nearby structures including hydrodissection, pneumodissection, and placing heated saline in sterile gloves on the skin surface. For abdominal wall desmoid tumors, the peritoneal cavity is insufflated with CO2 prior to freezing to protect the adjacent bowel and omentum. Cryoablation was performed with multiple freeze/thaw cycles and tract ablation where available. From January 2014 through September 2022, a total of 26 patients have successfully undergone desmoid ablation. The most common indication was pain. Complications encountered in 4 patients (skin discoloration which resolved, lower extremity motor weakness in 2 patients with desmoids involving lower extremity motor nerves, and infection requiring antibiotics). There were no instances of bowel injury or bleed requiring transfusion or intervention.


Conclusion and/or Teaching Points:

For DT candidates, evaluation of surrounding tissues for relative contraindications is extremely important. However, tumors abutting sensitive tissues can undergo ablation if proper safety techniques are used, including hydrodissection, pneumodissection, and peritoneal cavity insufflation. These methods can protect sensitive tissues from incurring damage during the freeze-thaw cycles. Further protection of the skin from the penetrating probes can be offered by a variety of sterile innovations. Cryoablation of DT is a safe and effective minimally invasive treatment option for desmoid tumors.