Preliminary toxicity results using partial breast 3D-CRT with once daily hypo-fractionation and deep inspiratory breath hold

Abstract

BackgroundTo evaluate the clinical outcomes of patients treated with 3D conformal Hypo-fractionated, deep Inspiratory breath-hold (DIBH), Partial breast radiotherapy, termed “HIP.” HIP was implemented to merge the schedule of once-daily breast hypofractionation with partial breast treatment.MethodsWe identified 38 breast cancers in 37 patients from 2013 to 2014 treated at our institution with HIP following lumpectomy for early stage breast cancer. Patients received a hypo-fractionated course (≤ 20 fractions) of once daily radiation to the partial breast (lumpectomy cavity + margin) utilizing DIBH regardless of laterality. Clinical and treatment-related characteristics were obtained, including target volume and organ at risk (OAR) dosimetric characteristics. Patients were followed clinically and with at least yearly mammograms for up to 36 months (range 5–36 months). Acute and late toxicity was scored using the Common Terminology Criteria for Adverse Events (CTCAE) v4.03.ResultsPatients received a median dose of 42.56 Gy in 16 Fractions (Fx) (range 40.05–53.2 Gy; and 15–20 Fx). OAR doses were low, with a mean heart dose of 0.37 Gy, an ipsilateral lung V20 mean of 4%, and a contralateral lung V5 of 1%. Acute toxicity (≤ grade 2) was present in 79% (n = 30) of the cases, with dermatitis being the most common finding (63%). Late grade 1–2 toxicity was present in 42% (n = 16) of the cases, with hyperpigmentation being the most common finding (n = 9). There were no severe acute or late toxicities (≥ grade 3). At a median follow up of 21 months, there were no local, regional, or distant failures.ConclusionsWe report limited toxicity in this low risk cohort of patients with early stage breast cancer treated with HIP, a unique and logical combination of 3-D conformal external beam radiotherapy, moderate hypo-fractionation, and DIBH.

Recent advances in radiotherapy of breast cancer

“…Usually these can be divided into surface-guided or spirometry-based systems [53]. DIBH is compatible with both, 3DCRT and IMRT/VMAT techniques [54], and also with APBI techniques [55]. Overall, DIBH results in considerably lower doses to the apex of the heart and other cardiac substructures (e.g.…”

Deep-inspirational breath-hold (DIBH) technique in left-sided breast cancer: various aspects of clinical utility

“…Since the dose to the OARs is rarely a problem during PBI, limited experience is published with PBI and DIBH [ 37 ]. The DIBH method utilized independently of the laterality of the disease was found useful for the PBI of 37 patients [ 39 ]. In our practice, heart and LAD exposure clearly depended on the size and location of the tumor bed.…”