Does accelerated hypofractionated adjuvant whole-breast radiotherapy increase mammographic density or change mammographic features?

OBJECTIVE: To compare mammographic features before and after accelerated hypofractionated adjuvant whole-breast radiotherapy (AWB-RT) and to evaluate possible appearance of modifications. METHODS: A retrospective review of 177 females before and after an AWB-RT treatment (follow-up ranging from 5 to 9 years) was performed by four radiologists focused in breast imaging who independently evaluated diffuse mammographic density patterns and reported on possible onset of focal alterations; modifications in density and fibrosis with parenchymal distortion were deemed as indicators of AWB-RT treatment impact in breast imaging. RESULTS: Prevalent mammographic density (D) patterns in the 177 females evaluated were according to the American College of Radiology-Breast Imaging Reporting and Data System (ACR-BIRADS): D1, fibroadipose density (score percentage from 55.9% to 43.5%); and D2, scattered fibroglandular density (from 42.9% to 32.7%). No change in diffuse mammographic density and no significant difference in mammographic breast parenchymal structure were observed. "No change" was reported with score percentage from 87% to 79.6%. Appearance of fibrosis with parenchymal distortion was reported by all radiologists in only two cases (1.1%, p = 0.3); dystrophic calcification was identified with percentage score from 2.2% to 3.3% (small type) and from 9.6% to 12.9% (coarse type). CONCLUSION: No statistically significant changes in follow-up mammographies 5-9 years after AWB-RT were detected, justifying large-scale selection of AWB-RT treatment with no risk of altering radiological breast parameters of common use in tumour recurrence detection. ADVANCES IN KNOWLEDGE: The hypofractionated radiotherapy (AWB-RT treatment) is a new proven, safe and effective modality in post-operative patients with early breast cancer with excellent local control and survival. In our study, the absence of changes in mammographic density patterns and in breast imaging before and after AWB-RT treatment (up to 5-9 years after radiotherapy) justifies large-scale use of AWB-RT treatment without hindrance in tumour recurrence diagnosis.

Hypofractionation and concomitant boost to deliver adjuvant whole-breast radiation in ductal carcinoma in situ (DCIS): a subgroup analysis of a prospective case series.

To report the four-year outcomes of accelerated hypofractionated whole-breast radiotherapy (WBRT) with a concomitant boost (CB) to the tumor bed in ductal carcinoma in situ (DCIS), we performed a subgroup analysis of 103 patients affected with DCIS within a cohort of 960 early breast cancer patients treated with breast conservation and hypofractionated WBRT. Prescription dose to the whole breast was 45 Gy (2.25 Gy/20 fractions) with an additional daily CB of 0.25 Gy to the surgical cavity (2.5 Gy/20 fractions up to 50 Gy). With a median follow-up of 48 months (range 12-91), no local recurrence was observed. Maximum detected acute skin toxicity was as follows: G0 in 35 % of patients, G1 in 54 %, G2 in 9 % and G3 in 2 %. Late skin and subcutaneous toxicity were generally mild with only 1 % of patients experiencing ≥G3 events (telangiectasia). No major lung and heart toxicity were detected. Cosmetic results were excellent in 50 % of patients, good in 37 %, fair in 9 % and poor in 4 %. Quality of life had a generally favorable profile both within the functioning and symptoms domains. The present result supports the hypothesis that DCIS patients could be safely treated with a hypofractionated schedule employing a CB to the lumpectomy cavity.

Five-year results of a prospective case series of accelerated hypofractionated whole breast radiation with concomitant boost to the surgical bed after conserving surgery for early breast cancer.

Accelerated hypofractionation (HF) using larger dose per fraction, delivered in fewer fractions over a shorter overall treatment time, is presently a consistent possibility for adjuvant whole breast radiation (WBRT) after breast-conserving surgery for early breast cancer (EBC). Between 2005 and 2008, we submitted 375 consecutive patients to accelerated hypofractionated WBRT after breast-conserving surgery for EBC. The basic course of radiation consisted of 45 Gy in 20 fractions over 4 weeks to the whole breast (2.25 Gy daily) with an additional daily concomitant boost of 0.25 Gy up to 50 Gy to the surgical bed. Overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS) and local control (LC) were assessed. Late toxicity was scored according to the CTCAE v3.0; acute toxicity using the RTOG/EORTC toxicity scale. Cosmesis was assessed comparing treated and untreated breast. Quality of life (QoL) was determined using EORTC QLQ-C30/QLQ-BR23 questionnaires. With a median follow-up of 60 months (range 42-88), 5 years OS, CSS, DFS and LC were 97.6, 99.4, 96.6 and 100 %, respectively. Late skin and subcutaneous toxicity was generally mild, with few events > grade 2 observed. Cosmetic results were excellent in 75.7 % of patients, good in 20 % and fair in 4.3 %. QoL, assessed both through QLQ-C30/QLQ-BR23, was generally favorable, within the functioning and symptoms domains. Our study is another proof of principle that HF WBRT with a concurrent boost dose to the surgical cavity represents a safe and effective postoperative treatment modality with excellent local control and survival, consistent cosmetic results and mild toxicity.