Intraoperative avidination for radionuclide treatment as a radiotherapy boost in breast cancer: results of a phase II study with (90)Y-labeled biotin

Eur J Nucl Med Mol Imaging. 2010 Feb;37(2):203-11. doi: 10.1007/s00259-009-1260-4. Epub 2009 Sep 4.


Purpose: External beam radiotherapy (EBRT) after conservative surgery for early breast cancer requires 5-7 weeks. For elderly patients and those distant from an RT center, attending for EBRT may be difficult or impossible. We investigated local toxicity, cosmetic outcomes, and quality of life in a new breast irradiation technique-intraoperative avidination for radionuclide therapy (IART)-in which avidin is administered to the tumor bed and (90)Y-labelled biotin later administered intravenously to bind the avidin and provide irradiation. Reduced duration EBRT (40 Gy) is given subsequently.

Methods: After surgery, 50 (ten patients), 100 (15 patients) or 150 mg (ten patients) of avidin was injected into the tumor bed. After 12-24 h, 3.7 GBq (90)Y-biotin (beta source for therapeutic effect) plus 185 MBq (111)In-biotin (gamma source for imaging and dosimetry) was infused slowly. Whole-body scintigraphy and SPECT/CT images were taken for up to 30 h. Shortened EBRT started 4 weeks later. Local toxicity was assessed by RTOG scale; quality of life was assessed by EORTC QOL-30.

Results: Of 35 patients recruited (mean age 63 years; range 42-74) 32 received IART plus EBRT. 100 mg avidin provided 19.5 +/- 4.0 Gy to the tumor bed and was considered the optimum dose. No side-effects of avidin or (90)Y-biotin occurred, with no hematological or local toxicity. Local G3 toxicity occurred in 3/32 patients during EBRT. IART plus EBRT was well accepted, with good cosmetic outcomes and maintained quality of life.

Conclusions: IART plus reduced EBRT can accelerate irradiation after conservative breast surgery.

Publication types

  • Clinical Trial
  • Clinical Trial, Phase II
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Avidin / administration & dosage*
  • Biotin / administration & dosage*
  • Breast Neoplasms / radiotherapy*
  • Breast Neoplasms / surgery*
  • Drug Delivery Systems / methods*
  • Female
  • Humans
  • Intraoperative Care
  • Middle Aged
  • Radioimmunotherapy / methods*
  • Radiopharmaceuticals / therapeutic use
  • Radiotherapy, Adjuvant / methods
  • Treatment Outcome
  • Yttrium Radioisotopes / administration & dosage*


  • Radiopharmaceuticals
  • Yttrium Radioisotopes
  • Avidin
  • Biotin