Sobreimpresión en fracción única con braquiterapia intersticial de alta tasa en el tratamiento conservador del carcinoma de mama

Early-stage breast cancer conservative treatment: high-dose-rate brachytherapy boost in a single fraction of 700 cGy to the tumour bed

BACKGROUND AND PURPOSE

Conservative treatment represents the current therapy for early-stage breast cancer. When risk factors for local relapse exist, a tumour bed boost is required. Retrospectively, we evaluated the prognostic factors influencing local recurrence (LR), overall survival (OS) and disease-free survival (DFS).

MATERIAL AND METHODS

After conservative treatment, 210 patients received a single-dose HDR brachytherapy (HDRBT) boost between June 1996 and December 2005. Mean age was 57 years; 75% had invasive ductal carcinoma. The most frequent surgery was lumpectomy (55.7%); 39.4% were G3, 18.6% intraductal component >25% and only 22% had negative margins.

RESULTS

With a mean follow-up of 85 months, at 5 and 10 years the OS was 93% and 88%, DFS 92% and 89%, and LR 3.6% and 5.3%, respectively. For LR, the risk factors were carcinoma in situ, N+ and involved margins, whereas for metastasis, the risk factors were T2 tumours, stage III, N+ and the presence of local recurrence.

CONCLUSIONS

HDR-BT boost in one fraction is an effective, simple and safe method for reducing LR. The outpatient setting and shorter treatment duration represent undeniable advantages.

Breast-Conservative Surgery With Close or Positive Margins: Can the Breast Be Preserved With High-Dose-Rate Brachytherapy Boost?

PURPOSE

To evaluate the likelihood of preserving the breast in women who show close or positive margins after conservative surgery for early breast carcinoma.

METHODS AND MATERIALS

Since 1996, 125 women with less than 5 mm or positive margins and positive separate cavity margin sampling were entered in a prospective trial with high-dose radiotherapy. A standard dose of 50 Gy to the whole breast was followed by a high-dose-rate brachytherapy application delivering 3 fractions of 4.4 Gy in 24 hours. The median follow-up was 84 months.

RESULTS

There were only seven local recurrences, with an actuarial local control rate of 95.8% at 5 years and 91.1% at 9 years. Actuarial overall and cause-specific survival rates were 92.6% and 95% at 5 years and 86.7% and 90.4% at 9 years, respectively. Late fibrosis was the most common complication, in 30% of patients, with good or excellent cosmetic results in 77%. The final result was that 95.2% of breasts were preserved.

CONCLUSIONS

Close or positive-margin breast cancer can be well managed with a high-dose boost in a wide tumor bed by means of high-dose-rate brachytherapy. This technique can avoid mastectomy or poor cosmetic resection, with minimal risk of local or general failure.