Toxicity of Three-Dimensional Conformal Radiotherapy for Accelerated Partial Breast Irradiation

Journal Article · Tue Dec 01 04:00:00 EST 2009 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2009.01.009· OSTI ID:21367532

Tokita, Mari; MacAusland, Stephanie G ^[1]; Evans, Suzanne B ^[2]; Hiatt, Jessica R ^[1]; Price, Lori Lyn ^[3]; DiPetrillo, Thomas; Wazer, David E ^[2]

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1. Department of Radiation Oncology, Brown University, Rhode Island Hospital, Providence, RI (United States)
2. Department of Radiation Oncology, Tufts University, Tufts Medical Center, Boston, MA (United States)
3. Biostatistics Research Center, Tufts University, Tufts Medical Center, Boston, MA (United States)

Purpose: To assess the incidence and severity of late normal tissue toxicity using three-dimensional conformal radiotherapy to deliver accelerated partial breast irradiation. Methods and Materials: A total of 60 patients were treated with three-dimensional conformal radiotherapy for accelerated partial breast irradiation. Treatment planning and delivery were in strict accordance with the technique and specified dose-volume constraints of the National Surgical Adjuvant Breast and Bowel Project B-39/Radiation Therapy Oncology Group 0413 protocol. Late toxicity was evaluated according to the Radiation Therapy Oncology Group grading schema. The cosmetic outcome was scored using the Harvard criteria. Univariate logistic regression analysis was performed to evaluate the correlation of dosimetric variables with outcome. Results: At a median follow-up of 15 months, moderate-to-severe late toxicity developed in 10% of patients. The most pronounced late toxicity was subcutaneous fibrosis: 25% Grade 2-4 and 8.3% Grade 3-4. The modified planning tumor volume/whole breast volume ratio, ratio of the volume of breast tissue receiving 5%, 20%, 50%, and 80% of the prescription dose to the whole breast volume, and maximal dose within the breast correlated with the development of fibrosis (p = .10, p = .03, p = .04, p = .06, p = .09, and p = .046, respectively). The overall cosmetic outcome was good to excellent in 81.7%, fair in 11.7%, and poor in 6.7%. The presence of subcutaneous fibrosis, modified planning tumor volume/whole breast volume ratio, ratio of the volume of breast tissue receiving 5% and 20% of the prescription dose to the whole breast volume, and pathologic specimen volume correlated with the risk of a fair/poor cosmetic outcome (p < .001, p = .02, p = .05, p = .04, p = .01, respectively). Conclusion: The three-dimensional conformal radiotherapy technique for accelerated partial breast irradiation as specified in the National Surgical Adjuvant Breast and Bowel Project B-39/Radiation Therapy Oncology Group 0413 protocol resulted in a remarkably high rate of moderate-to-severe late normal tissue effects, despite the relatively brief follow-up period. The toxic events correlated clearly with several dose-volume parameters.

• OSTI ID: 21367532
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 5 Vol. 75; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BODY
DISEASES
FIBROSIS
GLANDS
MAMMARY GLANDS
MEDICINE
NEOPLASMS
NUCLEAR MEDICINE
ORGANS
PATHOLOGICAL CHANGES
RADIOLOGY
RADIOTHERAPY
THERAPY
THREE-DIMENSIONAL CALCULATIONS
TOXICITY