For patients with recurrent or metastatic soft tissue sarcoma after failed surgical, radiation or chemotherapy treatment, computed tomography (CT)-guided percutaneous cryoablation may provide a viable option.
In a retrospective study, recently published in the American Journal of Roentgenology, interventional radiologists and oncologist researchers assessed the use of CT-guided percutaneous cryoablation to treat a total of 250 recurrent or metastatic soft tissue sarcomas in 141 patients (median age of 66). The study authors noted 56 cases of leiomyosarcoma and 39 cases of liposarcoma, and a mean long-axis diameter of 2 cm for the lesions treated in the study.
The researchers said percutaneous cryoablation had an 86 percent rate of local progression-free survival at one year and 79 percent at two years after the procedure. Overall survival rates were 89 percent at one year and 80 percent at two years, according to the study authors. Forty-five percent of the cohort had chemotherapy-free survival at one year with 31 percent of patients maintaining chemotherapy-free survival at two years.
“The findings overall support cryoablation as an option for achieving local control in patients with treatment-refractory (soft tissue sarcoma),” wrote lead study author Koustav Pal, MBBS, who is affiliated with the Department of Interventional Radiology at the MD Anderson Cancer Center in Houston, and colleagues.
While the authors noted no significant differences in overall one- and two-year survival rates between those with liposarcoma and people with leiomyosarcoma, patients treated for leiomyosarcoma had significantly higher rates of local progression-free survival at one (89 percent vs. 76 percent) and two years (85 percent vs. 48 percent) than patients with liposarcoma.
“This difference could relate to variation among histologic types in the difficulty of performing ablation (in turn potentially related to variable difficulty in assessing ice-ball margins) or to variable ablation resistance among histologic types,” suggested Pal and colleagues.
Key advantages of cryoablation include the aforementioned chemotherapy “holidays,” the capability to treat multiple lesions in one outpatient procedure, and no prolonged cessation of systemic therapies, according to the study authors. The researchers noted that cryoablation facilitates other pertinent benefits.
Three Key Takeaways
- Efficacy of CT-guided percutaneous cryoablation. The procedure demonstrated an 86 percent rate of local progression-free survival at one year and 79 percent at two years. Overall survival rates were 89 percent at one year and 80 percent at two years. This suggests that cryoablation can effectively control local tumor progression in patients with recurrent or metastatic soft tissue sarcoma.
- Comparison of leiomyosarcoma and liposarcoma outcomes. Patients treated for leiomyosarcoma had significantly higher rates of local progression-free survival at one year (89 percent vs. 76 percent) and two years (85 percent vs. 48 percent) compared to those with liposarcoma. This indicates potential differences in how these histologic types respond to cryoablation.
- Advantages and safety profile: Cryoablation offers several benefits, including the ability to treat multiple lesions in one outpatient procedure, the potential for repeated treatments without systemic toxicities, and no need for prolonged cessation of systemic therapies. The procedure had a low complication rate (2 percent), with only four complications reported out of 217 procedures, demonstrating its relative safety.
“ … Cryoablation does not preclude additional local treatments, such as surgery or radiation, to the ablated area. Finally, in contrast with surgery and radiation, cryoablation can be repeated without concern for systemic toxicities,” emphasized Pal and colleagues.
The study authors noted a total of four complications out of the 217 percutaneous cryoablation procedures (2 percent) performed. Transarterial embolization was required for two post-cryoablation bleeding episodes. One patient had transient saphenous nerve damage that spontaneously resolved in several weeks, according to the researchers. They added that another patient developed a chest wall lesion and subsequent pneumothorax, which necessitated use of a small chest tube for two days.
(Editor’s note: For related content, see “Can MRI Surveillance Have an Impact in Detecting Recurrence of Soft Tissue Sarcomas?,” “SNMMI: Study Finds FAP-Targeted Radioligand Therapy Beneficial for Patients with Advanced Sarcomas” and “Interventional Radiology Study Shows Low Breast Cancer Recurrence 16 Months After Cryoablation.”
Beyond the inherent limitations of a single-center retrospective study, the authors acknowledged the lack of comparison between cryoablation and other treatment options. They also conceded the assessment of progression-free survival did not consider the presence of multiple lesion treatment for some of the patients in the study. The researchers pointed out that different cryoablation techniques may have been utilized and that all pre-procedure and post-procedure imaging was reviewed by one interventional radiologist.
