Ultrasound-guided radiofrequency (RF) ablation was well tolerated and delivered a 95 percent tumor ablation rate at one-year follow-up, according to results of single-center, prospective study published in the August issue of Radiology.
Elderly women with breast cancer may present with contraindications to breast-conserving treatments, including physiologic alterations, comorbid diseases and higher risk of complications. In other cases, elderly patients may decline surgery.
Previous pilot studies of RF ablation had suggested the technique is tolerated and feasible among breast cancer patients. However, long-term follow-up on elderly patients had not been performed, thus long-term efficacy data had not been established.
Jean Palussière, MD, from the department of interventional radiology at Institut Bergoniè in Bordeaux, France, and colleagues designed a single-arm study to determine the efficacy of RF ablation, as determined by recurrences at one year, and patient tolerance of the approach among elderly women who decline or are not candidates for surgery. The secondary endpoint was delayed local efficacy of ablation for patients who completed five years of endocrine therapy.
The researchers enrolled 21 women (median age, 79 years) diagnosed with endocrine-sensitive breast cancer from December 2004 to April 2010. Inclusion criteria were a tumor diameter of 3 cm or less after six months of endocrine therapy and a location at least 1 cm from the skin, nipple and chest wall.
Neoadjuvant endocrine therapy was delivered for six months, and then the tumor was re-evaluated. RF ablation was delivered under ultrasound guidance, and patients proceeded to receive another 4.5 years of endocrine treatment. Imaging follow-up included mammography, dynamic contrast-enhanced MRI and ultrasound.
Median follow-up time was 49.6 months, and complete five-year follow-up data were available for 10 patients.
Although four patients had skin burns, all patients tolerated RF ablation well and there were no interruptions during treatment, according to Palussière and colleagues.
All patients presented with a firm mass in the treated area at two months, which decreased in size by six months. Mammography showed the pre-ablation density progressively disappeared and was replaced by an “architectural disturbance surrounded by a halo corresponding to the limit of heating.”
One patient recurred at nine months, resulting in a 95 percent tumor ablation rate at one year.
Of the 10 patients with complete five-year data, three had local-regional recurrence outside of the ablation zone. Two of these had primary lobular cancer; both patients underwent surgery. Pathologic analysis did not detect disease in the ablation zone. These results show that relapses were delayed (30, 48 and 60 months), according to the researchers.
Although patients in this study were hospitalized for 24 hours according to study protocol, the ease of the procedure and lack of complications suggest that the procedure could be performed on an outpatient basis for some patients, noted Palussière and colleagues.
“The results of this study confirm that RF ablation can control local breast tumor evolution for tumors that have been successfully reduced to 3 cm with neoadjuvant endocrine therapy, excluding invasive lobular carcinoma, and is particularly suitable for elderly patients,” wrote Palussière et al.