Implementation of image-guided intensity-modulated accelerated partial breast irradiation : Three-year results of a phase II clinical study.

PURPOSE: To report 3­year results of accelerated partial breast irradiation (APBI) using image-guided intensity-modulated radiotherapy (IG-IMRT) following breast conserving surgery (BCS) for low-risk early invasive breast cancer. PATIENTS AND METHODS: Between July 2011 and March 2014, 60 patients with low-risk early invasive breast cancer underwent BCS and were enrolled in this phase II prospective study. The total dose was 36.9 Gy (9 fractions of 4.1 Gy, two fractions/day). Patient setup errors were detected in LAT, LONG and VERT directions. Local tumour control, survival results, early and late side effects and cosmetic outcome were assessed. RESULTS: At a median follow-up of 39 months, all patients were alive and neither locoregional nor distant failure occurred. One contralateral breast cancer and two new primary malignancies outside the breast were observed. No grade (G) 3-4 acute toxicity was detected. G1 and G2 erythema occurred in 21 (35%) and 2 (3.3%) patients, respectively; while G1 oedema was observed in 23 (38.8%) cases. G1 and G2 pain was reported by 6 (10%) and 2 (3.3%) patients, respectively. Among the late radiation side effects, G1 pigmentation or telangiectasia, G1 fibrosis and G1 asymptomatic fat necrosis occurred in 10 (16.7%), 7 (11.7%) and 3 (5%) patients, respectively. No ≥ G2 late toxicity was detected. Cosmetic outcome was excellent in 43 (71.7%) and good in 17 (28.3%) patients. CONCLUSION: IG-IMRT is a reproducible and feasible technique for delivery of external beam APBI following BCS for treatment of low-risk, early-stage invasive breast carcinoma. In order to avoid toxicity, image guidance performed before each radiation fraction is necessary to minimize the PTV. Three-year results are promising, early and late radiation side-effects are minimal, and cosmetic results are excellent to good.

Interobserver variations of target volume delineation in multicatheter partial breast brachytherapy after open cavity surgery.

PURPOSE: To investigate interobserver variations of target volume delineations in accelerated partial breast irradiation with multicatheter brachytherapy (BT) and to assess the impact of guidelines on consistency of contouring. METHODS AND MATERIALS: A contouring study with two phases in interstitial accelerated partial breast irradiation after open cavity surgery was conducted by the Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology Breast Cancer Working Group. Contours of cavity and planning target volume (PTV) on preimplant and postimplant CT images were delineated. In Phase 1, nine radiation oncologists defined the target volumes of 5 patients, whereas in Phase 2, four observers draw the contours of 4 patients applying guidelines. In Phase 1, experience in breast BT after open cavity surgery was assessed. The delineations were compared between Phase 1 and Phase 2, the impact of guidelines was assessed, and cavity visualization score was related to consistency of delineations. RESULTS: Significant interobserver variability in delineations of lumpectomy cavity and PTV was observed among the participants. Observers with BT experience after open cavity surgery outlined the cavity and PTV more consistently (conformity indexgen: 0.52 vs. 0.48 and 0.59 vs. 0.55 for preimplant and postimplant cavities). For all volumes, the mean Vmax/Vmin was 2.2 vs. 2.8. Having used guidelines all conformity indices increased significantly. For cavity, the increase was 14% and 11%, whereas for the PTV, 28% and 17% on the preimplant and postimplant CT images, respectively. A strong correlation was found between consistency of contours and cavity visualization score. CONCLUSIONS: Simple guidelines on defining the lumpectomy cavity significantly increased the consistency of contouring. Reliable consistency of target volume definition can be expected only for good cavity visibility.

[Accelerated partial breast irradiation with image-guided intensity-modulated radiotherapy following breast-conserving surgery - preliminary results of a phase II clinical study]. / Gyorsított, részleges külsõ emlõbesugárzás képvezérelt, intenzitásmodulált radioterápiával emlõmegtartó mûtét után - Fázis II klinikai vizsgálat elõzetes eredményei.

The purpose of the study was to implement accelerated partial breast irradiation (APBI) by means of image-guided intensity-modulated radiotherapy (IG-IMRT) following breast-conserving surgery (BCS) for low-risk early invasive breast cancer. Between July 2011 and March 2014, 60 patients with low-risk early invasive (St I-II) breast cancer who underwent BCS were enrolled in our phase II prospective study. Postoperative APBI was given by means of step and shoot IG-IMRT using 4 to 5 fields to a total dose of 36.9 Gy (9×4.1 Gy) using a twice-a-day fractionation. Before each fraction, series of CT images were taken from the region of the target volume using a kV CT on-rail mounted in the treatment room. An image fusion software was used for automatic image registration of the planning and verification CT images. Patient set-up errors were detected in three directions (LAT, LONG, VERT), and inaccuracies were adjusted by automatic movements of the treatment table. Breast cancer related events, acute and late toxicities, and cosmetic results were registered and analysed. At a median follow-up of 24 months (range 12-44) neither locoregional nor distant failure was observed. Grade 1 (G1), G2 erythema, G1 oedema, and G1 and G2 pain occurred in 21 (35%), 2 (3.3%), 23 (38.3%), 6 (10%) and 2 (3.3%) patients, respectively. No G3-4 acute side effects were detected. Among late radiation side effects G1 pigmentation, G1 fibrosis, and G1 fat necrosis occurred in 5 (8.3%), 7 (11.7%), and 2 (3.3%) patients, respectively. No ≥G2 late toxicity was detected. Excellent and good cosmetic outcome was detected in 45 (75%) and 15 (25%) patients. IG-IMRT is a reproducible and feasible technique for the delivery of APBI following conservative surgery for the treatment of low-risk, early-stage invasive breast carcinoma. Preliminary results are promising, early radiation side effects are minimal, and cosmetic results are excellent.

Accelerated partial breast irradiation with external beam three-dimensional conformal radiotherapy. Five-year results of a prospective phase II clinical study.

PURPOSE: The aim of this study was to report the 5-year results of accelerated partial breast irradiation (APBI) using external beam three-dimensional conformal radiotherapy (3D-CRT). PATIENTS AND METHODS: Between 2006 and 2011, 44 patients with low-risk, stage I-II breast cancer underwent breast-conserving surgery. Postoperative APBI was given by means of 3D-CRT using three to five non-coplanar fields. The total dose of APBI was 36.9 Gy (nine fractions of 4.1 Gy b.i.d.). The mean follow-up time was 58.2 months for surviving patients. Survival results, side effects, and cosmetic results were assessed. RESULTS: One (2.3%) local recurrence was observed, for a 5-year actuarial rate of 3.7%. Neither regional nor distant failure was observed. Two patients died of internal disease. The 5-year disease-free, cancer-specific, and overall survival rates were 96.3, 100, and 95.1%, respectively. Acute side effects included grade 1 (G1) erythema in 75%, G1 parenchymal induration in 46%, and G1 pain in 46% of patients. No G2 or higher acute side effect occurred. Late side effects included G1, G2, and G3 fibrosis in 44, 7, and 2% of patients, respectively, G1 skin pigmentation in 12%, and G1 pain in 2%. Asymptomatic fat necrosis occurred in 14%. Cosmetic results were rated excellent or good in 86% of cases by the patients themselves and 84% by the physicians. CONCLUSIONS: The 5-year local tumor control, toxicity profile, and cosmetic results of APBI delivered with external beam 3D-CRT are encouraging and comparable to other APBI series.

[Accelerated partial breast irradiation with three-dimensional conformal external beam radiotherapy following breast-conserving surgery -- preliminary results of a phase II clinical study]. / Akcelerált parciális konformális külso emlobesugárzás emlomegtartó mûtét után - fázis II prospektív klinikai vizsgálat elozetes eredményei.

The aim of the study was to implement accelerated partial breast irradiation (APBI) by means of three-dimensional conformal radiotherapy (3D-CRT) following breast-conserving surgery (BCS) for early-stage breast cancer. Between December 2006 and February 2011, in 45 cases of low-risk, stage I-II breast cancer the tumour bed was marked with titanium clips during BCS. Postoperative APBI was given by means of 3D-CRT using 3 to 5 non-coplanar fields. The total dose of APBI was 36.9 Gy (9 x 4.1 Gy) using a twice-a-day fractionation over 5 consecutive days. Early and late radiation side effects and cosmetic results were analysed for the first 30 patients with a minimum follow-up of 1 year. At a mean follow-up of 25.2 months neither loco-regional nor distant failure was observed. Excellent, good, fair, and poor cosmetic outcome was detected in 10 (33.3%), 16 (53.4%), 4 (13.3%), and 0 (0%) patients, respectively. Grade 2 or worse acute side effect was not observed. Grade 1 fibrosis, grade 2 teleangiectasia and asymptomatic fat necrosis occurred in 4 (13.3%), 1 (3.3%) and 5 (16.7%) patients, respectively. No grade 3-4 late side effects were detected. 3D-CRT is a reproducible and feasible technique for the delivery of APBI following conservative surgery for the treatment of low-risk, early-stage invasive breast carcinoma. The preliminary results are promising, early- and mid-term radiation side effects are rare, and cosmetic results are excellent.

[Local relapse in young (< or = 40 years) women with breast cancer after mastectomy or breast conserving surgery: 15-year results]. / Lokális recidíva fiatal (< or = 40 év) emlorákos betegeknél emlomegtartó mutét vagy mastectomia után: 15 éves eredmények.

PURPOSE: Data from various sources indicate that after breast conserving surgery (BCS), younger patients have a high risk of local relapse, but there is insufficient evidence about the risk of post-mastectomy local recurrence. This study investigates the risk of local recurrence for young (< or = 40 years) patients treated with either conservative or radical surgery, with or without radiotherapy (RT). METHODS: 148 young (< or = 40 years) women with early invasive breast cancer underwent axillary dissection and mastectomy (n = 92) or BCS (n = 56) between January 1983 and December 1997. When adjuvant RT was given, the median dose was 50 Gy. The risk factors of local recurrence were estimated by uni- and multivariate analysis. RESULTS: At a median follow-up time of 199 months 60 (40.5%) women died of breast cancer. The type of surgery (mastectomy vs. wide tumour excision) had no significant impact on breast cancer-specific survival. The crude rate of local relapse for nonirradiated mastectomy and BCS patients was 24% and 75% (p = 0.0041), and for irradiated patients 4% and 23%, respectively (p = 0.0091). After mastectomy in univariate analysis nodal status (negative vs. positive) and RT (no vs. yes) were significant predictors of local control, but tumour size (T1 vs. T2) and histological grade (1-2 vs. 3) were not. In multivariate analysis both nodal involvement and omission of RT remained independent significant negative predictors of local control. After BCS in univariate analysis extensive intraductal component (EIC, negative vs. positive) and RT (no vs. yes) were significant predictors of local control, but tumour size (T1 vs. T2), nodal status (N0 vs. N1) and histological grade (1-2 vs. 3) were not. In multivariate analysis omission of RT and presence of EIC remained independent significant negative predictors of local control. The 15-year actuarial rate of local relapse was 29% for irradiated, and 75% for nonirradiated BCS patients (RR, 0.21; 95% CI, 0.07-0.55; p = 0.0052). The 15-year actuarial rate of local recurrence was 6% for irradiated, and 46% for nonirradiated node-positive mastectomy patients (RR, 0.12; 95% CI, 0.06-0.96; p = 0.0095). CONCLUSION: The incidence of local recurrence is high for young patients treated either with BCS or mastectomy, and RT significantly reduces the risk. The use of postmastectomy RT in node-positive patients gives a good local control. The efficacy of BCS and RT as a treatment modality for young patients needs further investigations.