Three‐year analysis of treatment efficacy, cosmesis, and toxicity by the American Society of Breast Surgeons MammoSite Breast Brachytherapy Registry Trial in patients treated with accelerated partial breast irradiation (APBI)

Abstract

BACKGROUND. This report presents 3 years of data on treatment efficacy, cosmetic results, and toxicities for patients enrolled on the American Society of Breast Surgeons MammoSite (Cytyc, Bedford, Mass) Breast Brachytherapy Registry Trial. METHODS. A total of 1440 patients (1449 cases) with early stage breast cancer who were undergoing breast‐conserving therapy were treated with the MammoSite device to deliver accelerated partial breast irradiation (APBI) (34 Gy in 3.4 Gy fractions). Of these, 1255 (87%) cases had invasive breast cancer (IBC; median size = 10 mm), and 194 (13%) cases had ductal carcinoma in situ (DCIS; median size = 8 mm). Median follow‐up was 30.1 months. RESULTS. Twenty‐three (1.6%) cases developed an ipsilateral breast tumor recurrence (IBTR) for a 2‐year actuarial rate of 1.04% (1.11% for IBC and 0.59% for DCIS). No variables were associated with IBTR. Six (0.4%) patients developed an axillary failure. The percentages of breasts with good to excellent cosmetic results at 12 (n = 980), 24 (n = 752), 36 (n = 403), and 48 months (n = 67 cases) were 95%, 94%, 93%, and 93%, respectively. Breast seromas were reported in 23.9% of cases (30% in open‐cavity implants and 19% in closed‐cavity implants). Symptomatic seromas occurred in 10.6% of cases, and 1.5% of cases developed fat necrosis. A subset analysis of the first 400 consecutive cases enrolled was performed (352 with IBC, 48 DCIS). With a median follow‐up of 37.5 months, the 3‐year actuarial rate of IBTR was 1.79%. CONCLUSIONS. Treatment efficacy, cosmesis, and toxicity 3 years after treatment with APBI using the MammoSite device are good and similar to those reported with other forms of APBI with similar follow‐up. Cancer 2008. © 2008 American Cancer Society.

Current status and perspectives of brachytherapy for breast cancer

“…[81][82][83][84][85][86][87][88][89][90][91][92] To date, only two groups have reported their 81 Criteria for entry into the study were unifocal invasive ductal carcinoma, tumor size 2 cm or less, age 45 years or more, absence of EIC, cavity size 3 cm or more, negative axillary nodes, and clear fi nal surgical margins. A minimum balloon-to-skin surface distance of 5 mm was required.…”

“…In the United States, the MammoSite system has been implemented by a number of institutions. [81][82][83][84][85][86][87] In Europe, several feasibility studies have been initiated to investigate the practicability and safety of the system. [88][89][90][91][92] Most of these trials have been designed to test the device as the sole method for APBI and for the delivery of a boost dose in combination with WBI.…”

Assessment of Accelerated Partial Breast Irradiation as Monotherapy Following Breast Conserving Surgery in the Treatment of Favorable Risk Breast Cancer

“…Furthermore, the balloon surface should be at least 7 mm beneath the surface of the skin. Correctly fitted applicators are believed to have dose distributions similar to those achieved with a fully encompassing multiple catheter implant [18] [45]. Once the device is appropriately placed, treatment is delivered with an HDR source which is inserted near the center of the balloon.…”

Accelerated Partial-Breast Irradiation: A State of the Art Strategy.

“…In general, total dose is 34 Gy over10 fractions , so 3.4 Gy per fraction, twice daily (minimum of 6 hours between fractions) over 1week. MBS has Good /excellent cosmesis with low risk of recurrence [39,40,41,42]. MBS has various disadvantages including: its central source channel does not allow for shaping radiation iso-dose curves in the direction perpendicular to the central channel; it is an invasive device and its applicator can be placed into the lumpectomy cavity at the time of surgery or in a separate procedure after surgery, using old or new incision; when applicator is inserted under ultrasound guidance, it needs good experience; it is not suitable technique for small breast or for tumors located in the upper-inner quadrant, due to needing of skin-cavity distances (Figure 4 a,b,c).…”