Patterns of use and short-term complications of breast brachytherapy in the national medicare population from 2008-2009

Treatment efficacy with accelerated partial breast irradiation (APBI): final analysis of the American Society of Breast Surgeons MammoSite(®) breast brachytherapy registry trial

BACKGROUND

The purpose of this study was to examine data on treatment efficacy, cosmesis and toxicities for the final analysis of the American Society of Breast Surgeons MammoSite(®) breast brachytherapy registry trial.

METHODS

A total of 1,449 cases of early-stage breast cancer underwent breast conserving therapy. The single-lumen MammoSite(®) device was used to deliver accelerated partial breast irradiation (APBI) (34 Gy in 3.4 Gy fractions). Of these, 1,255 cases (87 %) had invasive breast cancer (IBC) and 194 cases had DCIS. Median follow-up was 63.1 months with 45 % of all patients having follow-up of 6 years or longer.

RESULTS

There were 41 cases (2.8 %) that developed an ipsilateral breast tumor recurrence (IBTR) for a 5-year actuarial rate of 3.8 % (3.7 % for IBC and 4.1 % for DCIS). Tumor size (odds ratio [OR] = 1.1, p = 0.03) and estrogen receptor negativity (OR = 3.0, p = 0.0009) were associated with IBTR, while a trend was noted for positive margins (OR = 2.0, p = 0.06) and cautionary/unsuitable status compared with suitable status (OR = 1.8, p = 0.07). The percentage of patients with excellent/good cosmetic results at 60, 72, and 84 months was 91.3, 90.5, and 90.6 %, respectively. The overall rates of fat necrosis and infections remained low at 2.5 and 9.6 % with few late toxicity events beyond 2 years. The overall symptomatic seroma rate was 13.4 and 0.6 % beyond 2 years.

CONCLUSIONS

The final analysis of treatment efficacy, cosmesis, and toxicity from the American Society of Breast Surgeons MammoSite(®) breast brachytherapy registry trial confirms previously noted excellent results and compares favorably with other forms of APBI with similar follow-up and to outcomes seen in selected patients treated with whole breast irradiation.

Trends and clinical implications of preoperative breast MRI in Medicare beneficiaries with breast cancer

While there has been increasing interest in the use of preoperative breast magnetic resonance imaging (MRI) for women with breast cancer, little is known about trends in MRI use, or the association of MRI with surgical approach among older women. Using the Surveillance, Epidemiology and End Results-Medicare database, we identified a cohort of women diagnosed with breast cancer from 2000 to 2009 who underwent surgery. We used Medicare claims to identify preoperative breast MRI and surgical approach. We evaluated temporal trends in MRI use according to age and type of surgery, and identified factors associated with MRI. We assessed the association between MRI and surgical approach: breast-conserving surgery (BCS) versus mastectomy, bilateral versus unilateral mastectomy, and use of contralateral prophylactic mastectomy. Among the 72,461 women in our cohort, 10.1 % underwent breast MRI. Preoperative MRI use increased from 0.8 % in 2000-2001 to 25.2 % in 2008-2009 (p < 0.001). Overall, 43.3 % received mastectomy and 56.7 % received BCS. After adjustment for clinical and demographic factors, MRI was associated with an increased likelihood of having a mastectomy compared to BCS (adjusted odds ratio = 1.21, 95 % CI 1.14-1.28). Among women who underwent mastectomy, MRI was significantly associated with an increased likelihood of having bilateral cancer diagnosed (9.7 %) and undergoing bilateral mastectomy (12.5 %) compared to women without MRI (3.7 and 4.1 %, respectively, p < 0.001 for both). In conclusion, the use of preoperative breast MRI has increased substantially among older women with breast cancer and is associated with an increased likelihood of being diagnosed with bilateral cancer, and more invasive surgery.

Breast-conserving therapy with partial or whole breast irradiation: ten-year results of the Budapest randomized trial

BACKGROUND AND PURPOSE

To report the long-term results of a single-institution randomized study comparing the results of breast-conserving treatment with partial breast irradiation (PBI) or conventional whole breast irradiation (WBI).

PATIENTS AND METHODS

Between 1998 and 2004, 258 selected women with pT1 pN0-1mi M0, grade 1-2, non-lobular breast cancer without the presence of extensive intraductal component and resected with negative margins were randomized after BCS to receive 50 Gy WBI (n=130) or PBI (n=128). The latter consisted of either 7 × 5.2 Gy high-dose-rate (HDR) multi-catheter brachytherapy (BT; n=88) or 50 Gy electron beam (EB) irradiation (n=40). Primary endpoint was local recurrence (LR) as a first event. Secondary endpoints were overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), and cosmetic results.

RESULTS

After a median follow up of 10.2 years, the ten-year actuarial rate of LR was 5.9% and 5.1% in PBI and WBI arms, respectively (p=0.77). There was no significant difference in the ten-year probability of OS (80% vs 82%), CSS (94% vs 92%), and DFS (85% vs 84%), either. The rate of excellent-good cosmetic result was 81% in the PBI, and 63% in the control group (p<0.01).

CONCLUSIONS

Partial breast irradiation delivered by interstitial HDR BT or EB for a selected group of early-stage breast cancer patients produces similar ten-year results to those achieved with conventional WBI. Significantly better cosmetic outcome can be achieved with HDR BT implants compared with the outcome after WBI.

Survival after partial breast brachytherapy in elderly patients with nonmetastatic breast cancer

BACKGROUND

Despite growing utilization of accelerated partial breast irradiation using brachytherapy (APBI-Brachy) for elderly breast cancer patients, there are limited data from randomized Phase III trials to support its routine use. This study uses population-based data to examine whether APBI-Brachy results in comparable survival rates compared with whole breast irradiation (WBI).

METHODS

A sample of 29,647 female patients diagnosed with nonmetastatic breast cancer in 2002-2007 treated with breast-conserving surgery and radiotherapy was identified in the Surveillance, Epidemiology, and End Results Program-Medicare data set. Log-rank tests, Cox proportional hazards models, instrumental variable analysis, and subgroup analysis were used to study the comparative effectiveness of APBI-Brachy and WBI.

RESULTS

During a median followup of 3.6 and 4.8 years, 123 (7.7%) and 3438 (13.6%) patients died after APBI-Brachy and WBI, respectively. Recurrence-free survival (p = 0.9711) and overall survival rates (p = 0.0551) did not differ significantly between the two radiation modalities. After accounting for tumor characteristics, patient characteristics, community factors, and comorbidities, the recurrence-free survival (hazard ratio, 1.05; 95% confidence interval, 0.90-1.23; p = 0.5125) and overall survival (hazard ratio, 0.87; 95% confidence interval, 0.72-1.04; p = 0.1332) rates were still not significantly different between patients treated with APBI-Brachy and WBI.

CONCLUSION

Partial breast brachytherapy and WBI resulted in similar recurrence-free and overall survival rates in this cohort of elderly breast cancer patients, even after adjustment for the more favorable characteristics of patients in the former group. These findings will need to be confirmed by the randomized trials comparing these modalities.

[Brachytherapy of breast cancer]

For breast cancer, interstitial brachytherapy remains an accurate irradiation technique for delivering a high dose (increasing the local control) in a small volume (decreasing the toxicity). In this article, we present the technical data related to the breast brachytherapy proceeding, from the implantation of the vectors to the treatment itself, including the planning. The different indications of breast brachytherapy include all the breast irradiations focusing on the initial tumour bed (partial irradiation of the breast), such as boost, accelerated and partial breast irradiation (APBI) and second conservative radiosurgical treatment in case of ipsilateral in-breast recurrence. The results in terms of efficacy and toxicity are presented for each indication. Interstitial breast brachytherapy, performed according with the standard rules, remains a major technique for breast cancer treatment.