Strut-based accelerated partial breast irradiation: Report of treatment results for 250 consecutive patients at 5 years from a multicenter retrospective study.
PURPOSE
This registry trial studied the long-term outcomes of women receiving accelerated partial breast irradiation (APBI) using strut-based applicators and reports on the local control, toxicity, and survival for the first 250 patients treated with this device.


METHODS AND MATERIALS
Patients were treated using the strut-based brachytherapy device with conventional dose and fractionation of 34 Gy in 10 twice-daily fractions. Planning goals for the planning target volume were V90 > 90%, V150 < 50 cc, and V200 < 20 cc. Toxicity was graded based on the Common Terminology Criteria for Adverse Events v3.0. Recurrence rates were also calculated.


RESULTS
Median followup was 59.5 months for the 250 patients. Grade 2 or higher adverse events at any time for hyperpigmentation, induration, erythema, telangiectasia, breast pain, seroma, and fat necrosis were 0.4%, 3.0%, 3.0%, 3.0%, 3.9%, 4.8%, and 1.3%, respectively. The median V90 was 97%, V95 was 95.1%, V150 was 28.7 cc, and V200 was 14.2 cc. For those patients with a less than a 5-mm or 3-mm-skin bridge, the median skin max doses were 272 and 289 cGy, respectively. The 4-year actuarial recurrence rates for true recurrence/marginal miss and ipsilateral breast tumor recurrence were 2.3% and 3.6%, respectively. The 4-year actuarial rates for overall survival, cause-specific survival, and disease-free survival were 97%, 98%, and 92%, respectively.


CONCLUSIONS
The strut-based applicator was designed to simplify APBI compared to interstitial brachytherapy. This report confirms excellent tumor control and survival with low toxicity and supports the evidence that brachytherapy has less normal tissue toxicity than APBI with external beam irradiation.
['Yashar|Catheryn|C|', 'Attai|Deanna|D|', 'Butler|Ernest|E|', 'Einck|John|J|', 'Finkelstein|Steven|S|', 'Han|Ben|B|', 'Hong|Robert|R|', 'Komarnicky|Lydia|L|', 'Lyden|Maureen|M|', 'Mantz|Constantine|C|', 'Morcovescu|Serban|S|', 'Nigh|Stephen|S|', 'Perry|Kerri|K|', 'Pollock|Jondavid|J|', 'Reiff|Jay|J|', 'Scanderbeg|Daniel|D|', 'Snyder|Margaret|M|', 'Kuske|Robert|R|']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D001918:Brachytherapy D001943:Breast Neoplasms D018572:Disease-Free Survival D019583:Dose Fractionation, Radiation D005218:Fat Necrosis D005260:Female D006801:Humans D015412:Mastectomy, Segmental D008875:Middle Aged D009364:Neoplasm Recurrence, Local D011832:Radiation Injuries D011874:Radiometry D011879:Radiotherapy Dosage D018714:Radiotherapy, Adjuvant D012008:Recurrence D012189:Retrospective Studies D049291:Seroma D012867:Skin D013684:Telangiectasis D016896:Treatment Outcome
APBI Brachytherapy Interstitial Balloon based Breast brachytherapy Breast conservation Multilumen SAVI Strut Strut based