[Radiofrequency ablation of breast carcinomas: preliminary results of a clinical trial].

Objective: Among the alternatives to breast conserving surgery in breast cancer, radiofrequency ablation is the most widespread. We aimed to determine the feasibility, safety, and efficacy of this technique in our environment.

Material And Methods: We performed radiofrequency ablation of breast carcinomas under local anesthesia in the ultrasonography examination room. We included 35 patients (mean age=61.2+/-8.25 years) with invasive carcinomas measuring less than 2cm (mean diameter=8.9+/-2.9mm) and located far from the skin and chest wall. Prior to radiofrequency treatment, all patients underwent core biopsy to confirm that the tumors were invasive carcinomas and selective lymphadenectomy. Carcinomas were excised 2 to 4 weeks after radiofrequency treatment and analyzed histologically to evaluate the effects of radiofrequency treatment on the tumor and surrounding tissue. The degree of coagulation necrosis and involvement of the margins was evaluated using hematoxylin and eosin staining. Cellular viability or effectiveness of the radiofrequency treatment was evaluated using NADH diaphorase.

Results: In total, 85.7% of patients reported no discomfort; 11.4% reported mild, controllable pain. Intense pain required the procedure to be discontinued in one patient. No other complications occurred. Signs of coagulation necrosis were observed in all cases; coagulation necrosis was classified as complete in 32/35 (91.4%). NADH diaphorase was negative in 27 of the 32 cases in which it was performed; one case was slightly positive and the other four were impossible to evaluate.

Conclusion: Radiofrequency ablation of breast carcinomas is feasible, well tolerated, safe, and efficacious in nearly 90% of invasive tumors. The efficacy of the technique should be confirmed through extended follow-up of patients without subsequent surgical intervention in carefully designed and monitored phase III trials.