ASHBY: Accelerated Super-Hypofractionated Breast Brachytherapy

Accelerated Super-Hypofractionated Breast Brachytherapy - ASHBY Trial

The purpose of this study is to compare any good and bad effects of giving radiation treatment for breast cancer in 3 treatments over about 2 days.

This phase 2, single-arm prospective study has been designed to determine the safety of delivering accelerated partial breast irradiation (APBI) with a multicatheter interstitial implant in a short course over 1.5 days

Inclusion Criteria:

• Female

• New diagnosis of ductal carcinoma in situ (DCIS) and/or invasive breast carcinoma per histologic evaluation

• Age 45-79 at diagnosis

• Previous lumpectomy with surgical margins histologically free of invasive tumor and DCIS as determined by the pathologist.

• T stage of Tis, T1, or T2.

• T2 tumors must be ≤3 cm in maximum diameter

• If the tumor is human epidermal growth factor receptor 2 (HER2)-positive, the patient must receive HER2-directed therapy.

• For patients with invasive breast cancer, an axillary staging procedure must be performed (either sentinel node biopsy alone or axillary dissection [with a minimum of 6 axillary nodes removed]) and the axillary node[s] must be pathologically negative.

• Note: N0(i+) is not an exclusion criterion.

• Note: Patients meeting all of the following criteria are not required to undergo the axillary staging procedure:

  • ≥70 years of age
  • estrogen receptor, Her2 = human epidermal growth factor receptor 2, PR = progesterone receptor negative (ER+PR+HER2-)
  • G1-2
  • Tumor ≤2 cm in size
  • Agrees to comply with aromatase inhibitor recommendation

• Ability to understand and the willingness to sign a written informed consent document in English

Exclusion Criteria:

• Pregnant or breastfeeding
• Active collagen-vascular disease
• Paget's disease of the breast
• History of DCIS or invasive breast cancer prior to the current diagnosis
• Prior breast or thoracic radiation therapy (RT) for any condition
• Multicentric carcinoma (DCIS or invasive)
• Synchronous bilateral invasive or non-invasive breast cancer
• Surgical margins that cannot be microscopically assessed or that are positive
• Excision cavity that cannot be clearly delineated per the treating investigator
• Any of the dosimetric treatment criteria defined in Section 6.1 have not been met. Patients who become ineligible due to inability to meet dosimetric criteria should not receive treatment as - defined in this protocol and will come off the study. Any subsequent adjuvant radiation will be delivered at the discretion of the treating physician
• Medical, psychological, or social condition that, in the opinion of the investigator, may increase the patient's risk or limit the patient's adherence with study requirements