Image-guidedcryoablation in unresectable or recurrent advanced colorectal cancer: a retrospective study

Purpose: The present study retrospectively analyzed thesafety and efficacy of computed tomography (CT)-guided cryoablationin the treatment ofunresectable or recurrent advanced colorectal cancer, which did not respond well to or experienced progression with radiotherapy or chemotherapy. Materials and Methods: From January 2013 to April 2015, 31 lesions in 27 patients (16 males, 11 females; mean age of 57.2 years) with pelvic unresectableadvanced or recurrent colorectal cancer were included in the study. The tumor diameter was approximately 3.37 ±1.41 cm. The primary tumor included 25 rectal cancers, 1 sigmoid colon adenocarcinoma, and 1 ileocecal mucinous adenocarcinoma. Cryoablation was performed with 17-gauge cryoprobes and monitored by 64-slice spiral CT. Follow-up was carried out by contrast-enhanced magnetic resonance imaging (MRI). The treatment efficacy was evaluated by symptom palliation, decreased carcinoembryonic antigen (CEA) serum level, and tumor response. Results: The cryoablation procedure was well-tolerated in all patients without major complications or procedure-related mortality. Long-term complications included abscess formation (1 patient), skin frostbite and post-sacrum antrum formation (1 patient). Pain relief was satisfactory in patients with perineal pain (P<0.001), and the median time of pain relief was 3.0 months. Complete ablations were obtained in 22 lesions of 18 patients, while 9 lesions in 9 patients underwent incomplete ablation. The median time to local recurrence for lesions with complete ablations was 15.0 months, and that to the progression of tumors with incomplete ablation was 4.0 months. Conclusion: CT-guided cryoablation is a minimally invasive, safe, and effective therapeutic option for unresectableadvanced or recurrent colorectal cancer. The treatment is well-tolerated by patients, and pain relief is achieved rapidly.