Breast Irradiation In Patients Research Articles

144 (PB-051) Poster - Characteristics of breast radiotherapy patients experiencing breast oedema at a UK tertiary centre

144 (PB-051) Poster - Characteristics of breast radiotherapy patients experiencing breast oedema at a UK tertiary centre

Accelerated partial breast irradiation: Current evidence and future developments

AbstractWhole breast irradiation after breast‐conserving surgery for early breast cancer has become one of the standard treatment modes for breast cancer and yields the same effect as radical surgery. Accelerated partial breast irradiation (APBI) as a substitute for whole breast irradiation for patients with early breast cancer is a hot spot in clinical research. APBI is characterised by simple high‐dose local irradiation of the tumour bed in a short time, thus improving convenience for patients and saving costs. The implementation methods of APBI mainly include brachytherapy, external beam radiation therapy, and intraoperative radiotherapy. This review provides an overview of the clinical effects and adverse reactions of the main technologies of APBI and discusses the prospects for the future development of APBI.

Clinical Outcomes of Breast-Conserving Surgery with Synchronous 50-kV X-ray Intraoperative Partial Breast Irradiation in Patients Aged 64 Years or Older with Low-Risk Breast Cancer.

Breast-conserving surgery with synchronous 50-kV X-ray intraoperative radiation therapy (TARGIT-IORT) is a convenient form of partial breast irradiation; however, the existing literature supports a wide range of local control rates. We investigated the treatment effectiveness and toxic effects of TARGIT-IORT in a patient cohort aged 64 years or older with low-risk breast cancer. Retrospective analysis. Patients who received breast-conserving surgery with synchronous TARGIT-IORT at a single institution from 2016 to 2019 were reviewed. Additional whole breast irradiation was recommended at the discretion of the treating radiation oncologist. Baseline patient demographics and treatment details were recorded. Acute and chronic toxicities, measured using the Common Terminology Criteria for Adverse Events version 3.0 or 4.0 and breast cosmetic outcomes, using the Harvard Cosmesis score, were recorded. Locoregional recurrence, distant metastasis, and overall survival were recorded, and 5-year rates were estimated using the Kaplan-Meier method. 61 patients were included with a median follow-up of 3.5 years and median age of 72 years. Eight (13%) patients received additional whole breast irradiation, and fifty-four (89%) received adjuvant hormone therapy. There were no local, regional, or distance recurrences. One patient died of complications from COVID-19 infection. Grade 2 + acute and chronic toxicities were observed in 6 (12%) and 7 (14%) patients, respectively. One patient experienced a grade 3 acute toxicity. Cosmetic outcome was "excellent" or "good" in 45 (92%) patients. Breast TARGIT-IORT was well tolerated and conferred excellent disease control in this cohort of patients with low-risk breast cancer. While continued follow-up is required, TARGIT-IORT may be an appropriate treatment option for this population.

Early and Intermediate Treatment Outcome After Postoperative External Beam Accelerated Partial Breast Irradiation in Patients With Early-Stage Breast Cancer

Purpose/ObjectivesTo prospectively evaluate early and intermediate outcome after APBI in early-stage breast cancer patients. Materials/MethodsInclusion criteria were defined according to the APBI ASTRO CONSENSUS STATEMENT. The prescribed dose was 26-28 Gy in 5 fractions on 5 consecutive days. Regular follow-up visits with objective and subjective evaluation of treatment tolerance were performed after 0 and 2 weeks, 6 months and at annual intervals. ResultsBetween 02/2017-01/2020, 175 patients with breast conserving surgery met the inclusion criteria for APBI. Mean age was 65.7 years (range 46-88). 13% of patients were diagnosed with DCIS/Tis, 5/35/37% with T1a/b/c, and 10% with T2 stages, respectively. The mean volume of PTV was 119 cc (range 45-465), the ratio of mean PTV: whole breast volume ratio was 21% (7-53%). Mean follow-up was 42 months (median 45, range 0 – 67). Acute toxicity after 2 weeks was low with 69/26/5% grade 0/1/2.1, 2, 3, 4 and 5-year follow-up data was available from 146/134/107/73/25 patients. Patient-reported cosmetic outcomes were assessed excellent or good in 97.9/98.5/98.1/98.6/100%.Regarding grade 2 toxicities, as by now 3/2/2/0/0% G2 fibrosis, 1/1/0/0/0% G2 atrophy, no G2 skin telangiectasia or breast edema occurred. So far, none of the patients have experienced G3 toxicity or higher. The remaining patients had grade 0 or 1 toxicity only.Five ipsilateral breast recurrences (one marginally to PTV, four out-of-field) and five distant recurrences were recorded by now (03/2023). The 4-year in-breast recurrence rate was 2.5%. Eight patients died, two of them from disease. For all patients, the 4-year overall, cancer specific and disease-free survival rates were 97.1%, 99.4%, and 95.3%, respectively. ConclusionsHerewith we showed high early and intermediate term treatment tolerance and disease control of APBI using 26-28Gy in 5f/1w in carefully selected early breast cancer patients. APBI is highly appreciated by patients and efficient, as an additional advantage for busy centers.

Prospective Cohort Study to Evaluate Toxicity and Cosmesis between Interstitial APBI and Ultra-Hypo-Fractionated Whole Breast Irradiation in Patients with Early Breast Cancer

Both interstitial multi-catheter brachytherapy based accelerated partial breast irradiation (APBI) and ultra-hypo-fractionated whole breast irradiation (WBI) with 5 fractions can complete treatment in a short time and result in lower treatment-related costs. Although data are available on their toxicity compared with conventional and hypo-fractionated regimens, there are few data directly comparing these two techniques. This prospective cohort study enrolled early breast cancer patients with negative ink margin, T1 or T2 stage, and tumor size of 3 cm or less, with 0 to 3 positive lymph nodes after adequate axillary dissection or negative sentinel lymph node biopsy (N0-1), regardless of receptor status (ER, PR, HER2neu). Of the total 31 patients, 15 received APBI with multi-catheter interstitial brachytherapy (35 Gy in10 fractions over 5 days with a minimum interval of 6 hours between fractions) and 16 patients received WBI (27 Gy in 5 fractions over 5 days) with either 3DCRT or VMAT technique. Acute toxicity was assessed using the RTOG toxicity grading and breast cosmesis was assessed using the Harvard breast cosmesis score. Toxicity and cosmesis were assessed immediately after treatment, after one month, and after three months of treatment. Results were compared between groups using the Mann Whitney U test. All patients completed a 3-month follow-up after completion of treatment. There was no statistically significant difference between the 2 groups in terms of highest grade toxicity (p = 0.97) and acute toxicity immediately after RT (p = 1.0) and after 1 month of RT (p = 0.91). However, at 3 months, more patients in the WBI group had a residual skin reaction than in the APBI group (p = 0.03). There was no statistically significant difference in breast cosmesis scores at any time point. 53.3%, 6.6% had grade 1 and 2 skin toxicities respectively immediately after RT in the APBI group and 62.5% of patients had grade 1 skin toxicity in WBI group. After 1 month 26.6%, 26.6% & 13.3% patients had grade 2, grade 1 and grade 3 toxicities respectively. In the WBI group, at 1 month, 50%, 18.7% and 12.5% patients had grade 1, 3 and 2 skin toxicities respectively. At 3 months, 42.8% and 7.1% of patients in the APBI group had grade 1 and grade 2 toxicities, respectively. In the WBI group, 78.5% and 7.1% of patients had grade 1 and 2 skin toxicities respectively. In this study, no difference in acute toxicity or breast cosmesis was demonstrated between APBI-based interstitial brachytherapy and ultra-hypo-fractionated WBI. Since both regimens can be administered within 5 days, the decision between them is challenging for both physicians and patients. This study can be considered hypothesis-generating and used for further planning of equivalence or noninferiority studies.

Cardiopulmonary Protection for Bilateral Breast Irradiation: A Dosimetric Comparison between Proton and Photon Plans

Recent advances in cancer treatment improve cancer survivorship. Cardiovascular disease has become the leading cause of non-cancer death in breast cancer survivors. Therefore, risk of cardiopulmonary toxicities during multimodality treatment should be assessed carefully. It remains to be defined the best scenario for proton therapy to confer meaningful cardiovascular protection in the setting of breast irradiation. We hypothesized proton therapy plan provides optimal cardiopulmonary protection during bilateral breast irradiation. The study aimed to compare cardiopulmonary dosimetric parameters of proton and photon radiotherapy plans. We conducted a retrospective study and patients with bilateral breast cancer indicated for radiotherapy between January 01, 2010 and December 31, 2020 were included. All patients received whole breast or chest wall irradiation with or without regional nodal irradiation. The dose scheme was 50-50.4 Gy in 25-28 fractions. Boost was allowed if patients receiving breast conserving surgery or known risk factors. The dosimetric parameters included planning target volume, mean dose to the heart, the volume of whole lung receiving 5 Gy, 10 Gy, and 20 Gy. For photon therapy, volumetric modulated arc therapy using double partial arc plans was generated with Pinnacle 9.8, Elekta Synergy and tomotherapy helical plan was generated with Tomo Hi-Art planning system. For proton therapy, treatment planning was generated with Ray station 9A. All data was managed using SAS v.9.4 software. Analysis of variance (α = 0.05) was used to compute the dosimetry of different treatment modalities. The statistical significance was considered with a p-value <0.05. Thirty-one patients with bilateral breast cancer were included, including 12 bilateral breast irradiation patients and 6 bilateral chest wall irradiation patients. The mean dose of heart was 53.0±43.3 cGy in proton therapy while 736.6±225.1 cGy and 869.67±241.0 cGy in Tomotherapy and volumetric modulated arc therapy respectively. The volume of whole lung receiving 5 Gy was 15.4±7.91% in proton therapy while 46.1±10.8% and 46.3±2.5% in Tomotherapy and volumetric modulated arc therapy respectively. The volume of whole lung receiving 20 Gy was 7.7±4.3% in proton therapy while 15.4±5.6% and 19±3.5% in Tomotherapy and volumetric modulated arc therapy respectively. The effects of cardiopulmonary protection were more significant for chest wall irradiation over breast irradiation. Proton radiotherapy provided significant dose reduction for bilateral breast irradiation. The benefit is more significant is patients receiving bilateral chest wall irradiation. Further clinical validations will be warranted to confirm the clinical relevance of the finding.

Cicaderma® in radiation-related dermatitis of breast cancer: Results from the multicentric randomised phase III CICA-RT.

To prevent the occurrence of grade≥2 radiodermatitis after post-operative breast irradiation in patients with non metastatic breast cancer. This prospective randomised open-label multicenter study allocated patients from 3 French institutions, ≥18years, requiring postoperative radiotherapy for histologically proven, early-stage (non-metastatic) unilateral breast adenocarcinoma or in situ breast cancer, with R0 or R1 post-operative status, to receive hygiene rules, associated with either Cicaderma® (Arm A), or preventive treatment according to the investigator preference (mainly hyaluronic acid (ialuset®), essential oils, or water spray, or no medication (Arm B). The primary outcome was to compare the efficacy of Cicaderma® versus local standard management in preventing the occurrence of grade≥2 radiodermatitis. Main secondary objectives include Cicaderma® impact on radiotherapy discontinuation and on skin toxicity (pruritus), pain, quality of life, satisfaction. The CICA-RT study enrolled from June 2020 to April 2021, 258 women with a median age of 61 (22-91) years in 3 institutions. Patients received either Cicaderma® (A: N=130) or standard practice (B: N=128). In the 123 patients who initiated radiotherapy in each arm, 95 (77%, 95%CI 68.8%-84.3%) patients did not develop grade≥2 dermatitis. Sensitivity and per-protocol analyses confirmed the absence of differences between arms. This prospective study did not meet its primary endpoint of superiority of Cicaderma® over routine practice skin care in terms of prevention of acute radioinduced dermatitis of grade 2 or higher. However, Cicaderma® showed a significant decrease in the occurrence of pruritus with less patients reporting at least once grade≥2 pruritus (A: N=38, 31%; B: N=58, 47%; p=0.009).ClinicalTrials.gov identifier NCT04300829.

The Feasibility of Markerless Positioning on Breast-Conserving Radiotherapy Patients

<h3>Purpose/Objective(s)</h3> Currently, we are using a laser-based marking (LM) device to make the non-permanent reference markings for our breast radiotherapy patients. However, this method induces certain level of pain and leads to patient anxiety. Hence, we would like to investigate the possibilities of markerless positioning using our newly installed surface guided (SG) system. <h3>Materials/Methods</h3> 40 breast intact radiotherapy patients, who were treated between July 2021 to January 2022, were studied retrospectively. Firstly, the patient was aligned based on the three laser-based markings at the isocenter plane. The couch parameters (Data A) were recorded. Next, the patient was fine-tuned based on SG system to less than 1 mm and 1 degree and couch parameters (Data B) were recorded. Following by the CBCT, the image matching was done, and shifts were applied accordingly. Lastly, the final couch parameters (Data C) were recorded. All couch parameters were recorded in x, y and z axes. CBCTs were performed for the first three fractions and subsequently once a week across all the patients. The differences between Data B and Data C were identified as SG setup errors and the differences between Data A and Data C were identified as LM setup errors. Paired sample t-test was performed to compare the means between LM and SG positioning methods. P < 0.05 was considered as statistically significant. Bland-Altman plot was used to analyze the consistency between SG system and CBCT. <h3>Results</h3> The setup errors using LM and SG positioning were (0.20±0.12) cm, (0.25±0.18) cm, (0.37±0.24) cm and (0.11± 0.05) cm, (0.15±0.06) cm, (0.17±0.06) cm in x, y and z axes respectively. The systematic errors using SG positioning were significantly reduced (p <0.05) by 0.09cm, 0.1cm and 0.2cm in x, y and z axes. In addition, the absolute setup errors were all within 0.3cm in all directions. The setup accuracy using SG positioning was improved by 14.8%, 16.3% and 35.1% compared to LM positioning, in x, y and z directions. In bland-Altman scatter plot, 95% limits of agreement of x, y and z translation directions were (-0.30∼0.35), (-0.38∼0.40) and (-0.24∼0.48) cm respectively. Within the limits of agreement, the maximum absolute value of the difference was 0.3cm, 0.4cm, 0.4cm, respectively, and it was clinically acceptable. <h3>Conclusion</h3> The implementation of SG system in the breast intact radiotherapy workflow can improve the setup accuracy and making markerless positioning feasible. Furthermore, the strong correlation between SG and CBCT could potentially reduce the use of CBCT.

Optimal radiotherapy after breast-conserving surgery for early breast cancer: A network meta-analysis of 23,418 patients

PurposeIn order to explore whether partial breast irradiation can replace hypofractionated whole breast irradiation and whether the former two are superior to conventional fractionated whole breast irradiation, we conducted a network meta-analysis based on the data from the latest randomized controlled trials to evaluate the efficacy of these radiotherapy modalities. Material and methodsData from eligible studies were analyzed to determine the published events for ipsilateral breast tumor recurrence, distant metastasis, total deaths, and non-breast cancer-related deaths. In the case of low or high heterogeneity, the fixed-effect or random-effect model was used for statistical analysis respectively. NMA was performed by using the node-splitting model for two-category data among three radiotherapies based on a Bayesian method. ResultsA total of 23,418 patients were included in 16 studies. For ipsilateral breast tumor recurrence, both pairwise (OR=1.9; CI95%: 1.2 -2.8; p<0.05) and indirect (OR=1.7; CI95%: 1.2 -2.4; p<0.05) comparison of three radiotherapies by network meta-analysis showed that conventional fractionated whole breast irradiation was significantly better than partial breast irradiation. Indirect comparison of three radiotherapies by network meta-analysis showed that hypofractionated whole breast irradiation was significantly better than partial breast irradiation (OR=1.6; CI95%: 1.0 -2.5; p<0.05). Network and paired meta-analyses found no significant differences in other endpoints among the three radiotherapies. ConclusionOverall, this network meta-analysis showed that partial breast irradiation was related to the increase of ipsilateral breast tumor recurrence compared with hypofractionated or conventional fractionated whole breast irradiation in patients with early-stage breast cancer.

Mediators of Racial Disparities in Heart Dose Among Whole Breast Radiotherapy Patients.

Racial disparities in survival of patients with cancer motivate research to quantify treatment disparities and evaluate multilevel determinants. Previous research has not evaluated cardiac radiation dose in large cohorts of breast cancer patients by race nor examined potential causes or implications of dose disparities. We used a statewide consortium database to consecutively sample 8750 women who received whole breast radiotherapy between 2012 and 2018. We generated laterality- and fractionation-specific models of mean heart dose. We generated patient- and facility-level models to estimate race-specific cardiac doses. We incorporated our data into models to estimate disparities in ischemic cardiac event development and death. All statistical tests were 2-sided. Black and Asian race independently predicted higher mean heart dose for most laterality-fractionation groups, with disparities of up to 0.42 Gy for Black women and 0.32 Gy for Asian women (left-sided disease and conventional fractionation: 2.13 Gy for Black women vs 1.71 Gy for White women, P < .001, 2-sided; left-sided disease and accelerated fractionation: 1.59 Gy for Asian women vs 1.27 Gy for White women, P = .002). Patient clustering within facilities explained 22%-30% of the variability in heart dose. The cardiac dose disparities translated to estimated excesses of up to 2.6 cardiac events and 1.3 deaths per 1000 Black women and 0.7 cardiac events and 0.3 deaths per 1000 Asian women vs White women. Depending on laterality and fractionation, Asian women and Black women experience higher cardiac doses than White women. This may translate into excess radiation-associated ischemic cardiac events and deaths. Solutions include addressing inequities in baseline cardiac risk factors and facility-level availability and use of radiation technologies.

Validation of a Patient-Reported Outcome Measure for Moist Desquamation among Breast Radiotherapy Patients.

There has been an increasing interest in patient-reported outcome (PRO) measures in both the clinical and research settings to improve the quality of life among patients and to identify when clinical intervention may be needed. The primary purpose of this prospective study was to validate an acute breast skin toxicity PRO measure across a broad sample of patient body types undergoing radiation therapy. Between August 2018 and September 2019, 134 women undergoing adjuvant breast radiotherapy (RT) consented to completing serial PRO measures both during and post-RT treatment and to having their skin assessed by trained trial radiation therapists. There was high patient compliance, with 124 patients (92.5%) returning to the clinic post-RT for at least one staff skin assessment. Rates of moist desquamation (MD) in the infra-mammary fold (IMF) by PRO were compared with skin assessments completed by trial radiation therapists. There was high sensitivity (86.5%) and good specificity (79.4%) between PRO and staff-reported presence of MD in the IMF, and there was a moderate correlation between the peak severity of the MD reported by PRO and assessed by staff (rho = 0.61, p < 0.001). This prospective study validates a new PRO measure to monitor the presence of MD in the IMF among women receiving breast RT.

PO-1176 Dermal recall effect in breast radiotherapy patients after vaccine administration

PO-1176 Dermal recall effect in breast radiotherapy patients after vaccine administration

Investigation of VMAT-Cyberknife Virtual Treatment Plans in Accelerated Partial Breast Irradiation in Patients with Early Stage Breast Cancer

Erken evre meme kanserli hastalarda hızlandırılmış kısmi meme ışınlamasında Volümetrik Ark Terapi (VMAT) ve CyberKnife teknikleri kullanılarak hedef volüm ile kritik organ dozlarının karşılaştırılması amaçlanmıştır. Bu çalışma için radyoterapi almış 10 erken evre meme kanseri tanılı hasta seçilerek, günlük fraksiyon dozu 6 Gy ve toplam doz 30 Gy olacak şekilde VMAT ve CyberKnife (SBRT) sanal planları oluşturuldu. Homojenite indeksi (HI), konformite indeksi (CI), tedavi süresi (s), görünür hedef volümü (GTV) ve kritik organların aldığı doz değerleri karşılaştırıldı. Tedavi planları arasında GTV’nin Dmax (p=0,002) değeri VMAT tekniği lehine anlamlı fark bulundu. Aynı taraf memenin 30 Gy (V30) (p=0,013) ve 15 Gy alan (V15) volüm değerlerinin (p=0,007) CyberKnife tekniğinde daha az doz aldığı görüldü. Karşı memenin Dmax (p=0,218) değeri açısından anlamlı bir fark bulunmamıştır. Sağ meme yerleşimli olgularda kalbin Dmax (p=0,282) ve 1,5 Gy alan (V1,5) volümü için (p=0,548) anlamlı fark bulunmadı. Sol meme yerleşimli olgularda kalbin Dmax (p=0,095) değerinde anlamlı fark görülmedi; ancak kalbin 1,5 Gy alan (V1,5) volüm değerinin (p=0,008) CyberKnife tekniğinde daha düşük olduğu görüldü. Tedavi süresi (s) (p

Application of an automatic segmentation method for evaluating cardiac structure doses received by breast radiotherapy patients.

Quantifying radiation dose to cardiac substructures is important for research on the etiology and prevention of complications following radiotherapy; however, segmentation of substructures is challenging. In this study we demonstrate the application of our atlas-based automatic segmentation method to breast cancer radiotherapy plans for generating radiation doses in support of late effects research. We applied our segmentation method to contour heart substructures on the computed tomography (CT) images of 70 breast cancer patients who received external photon radiotherapy. Two cardiologists provided manual segmentation of the whole heart (WH), left/right atria, left/right ventricles, and left anterior descending artery (LAD). The automatically contours were compared with manual delineations to evaluate similarity in terms of geometry and dose. The mean Dice similarity coefficient between manual and automatic segmentations was 0.96 for the WH, 0.65 to 0.82 for the atria and ventricles, and 0.06 for the LAD. The mean average surface distance was 1.2mm for the WH, 3.4 to 4.1mm for the atria and ventricles, and 6.4mm for the LAD. We found the dose to the cardiac substructures based on our automatic segmentation agrees with manual segmentation within expected observer variability. For left breast patients, the mean absolute difference in mean dose was 0.1Gy for the WH, 0.2 to 0.7Gy for the atria and ventricles, and 1.8Gy for the LAD. For right breast patients, these values were 0.0Gy, 0.1 to 0.4Gy, and 0.4Gy, respectively. Our automatic segmentation method will facilitate the development of radiotherapy prescriptive criteria for mitigating cardiovascular complications.

The dosimetric benefit of in-advance respiratory training for deep inspiration breath holding is realized during daily treatment in left breast radiotherapy: Acomparative retrospective study of serial surface motion tracking.

IntroductionA novel approach of in‐advance preparatory respiratory training and practice for deep inspiration breath holding (DIBH) has been shown to further reduce cardiac dose in breast cancer radiotherapy patients, enabled by deeper (extended) DIBH. Here we investigated the consistency and stability of such training‐induced extended DIBH after training completion and throughout the daily radiotherapy course.MethodsDaily chestwall motion from real‐time surface tracking transponder data was analysed in 67 left breast radiotherapy patients treated in DIBH. Twenty‐seven received preparatory DIBH training/practice (prepTrn) 1–2 weeks prior to CT simulation, resulting in an extended DIBH (extDIBH) and reduced cardiac dose at simulation. Forty had only conventional immediate pre‐procedure DIBH instruction without prepTrn and without extended DIBH (non‐Trn group). Day‐to‐day variability in chestwall excursion pattern during radiotherapy was compared among the groups.ResultsThe average of daily maximum chestwall excursions was overall similar, 2.5 ± 0.6 mm for prepTrn/extDIBH vs. 2.9 ± 0.8 mm for non‐Trn patients (P = 0.24). Chestwall excursions beyond the 3‐mm tolerance threshold were less common in the prepTrn/extDIBH group (18.8% vs. 37.5% of all fractions within the respective groups, P = 0.038). Among patients with cardiopulmonary disease those with prepTrn/extDIBH had fewer chestwall excursions beyond 3 mm (9.4% vs. 46.7%, P = 0.023) and smaller average maximum excursions than non‐Trn patients (2.4 ± 0.3 vs. 3.0 ± 0.6 mm, P = 0.047, respectively).ConclusionSimilar stability of daily DIBH among patients with and without preparatory training/practice suggests that the training‐induced extended DIBH and cardiac dose reductions were effectively sustained throughout the radiotherapy course. Training further reduced beyond‐tolerance chestwall excursions, particularly in patients with cardiopulmonary disease.

Heart-related mortality after postoperative breast irradiation in patients with ductal carcinoma in situ in the contemporary radiotherapy era

Although radiation-induced cardiotoxicity has been addressed, its prognostic relevance to modern radiotherapy (RT) techniques is unclear. This study assessed the impact of adjuvant RT on heart-related deaths in patients with ductal carcinoma in situ. Patients who underwent adjuvant RT after breast-conserving surgery between 1988 and 2008 were identified from the Surveillance, Epidemiology, and End Results database. Kaplan‒Meier and competing risks analyses were conducted after propensity score-matching according to tumor laterality. A total of 41,526 propensity-matched patients were identified (n = 20,763 for either left- or right-sided tumor). In the analysis of the cumulative incidence of heart-related mortality events, there was a greater risk increment in the left-sided group over the first to second decades after RT in patients aged ≤ 50 years (P = 0.048). Competing risks analysis of the young patients showed that left-sided RT was associated with higher heart-related mortality rates (Grey’s test, P = 0.049). The statistical significance remained after adjusting for other covariates (subdistribution hazard ratio 2.35; 95% confidence interval 1.09‒5.10). Regarding the intrinsic effect of modern RT techniques, further strategies to reduce heart-related risks are needed for young patients. Close surveillance within an earlier follow-up period should be considered for these patients in clinics.

Comparing hypofractionated and conventionally fractionated whole breast irradiation for patients with ductal carcinoma in situ after breast conservation: a propensity score-matched analysis from a national multicenter cohort (COBCG-02 study).

Randomized trials confirmed the efficacy and the safety of hypofractionated whole breast irradiation (HF-WBI) in patients with early-stage breast cancer. However, the role of HF-WBI in patients with DCIS after breast conserving surgery has not yet been clearly established in prospective randomized trials. The aim of this study was to evaluate if HF-WBI can be considered comparable to conventionally fractionated (CF)-WBI in DCIS patients. The analysis included DCIS patients from four Italian centers treated with CF-WBI 50Gy/25 fractions or HFRT 40.5Gy/15 fractions, without tumor bed boost. A propensity score matching (PSM) analysis was performed using a logistic regression that considered age, grading, presence of necrosis, resection margin status and adjuvant endocrine therapy. Five hundred twenty-seven patients was included (367 in the CF-WBI-group and 160 in the HR-WBI group). After 1:1 matching, 101 patients were allocated to the CF-WBI-group and 104 to the HF-WBI group. No correlation was observed between the type of RT schedule and LRFS (HR 1.68, 95% CI 0.82-3.45; p = 0.152). After PSM, no statistical difference was observed between the two RT group (HR 1.11, 95% CI 0.40-3.04; p = 0.833), with 3- and 5-years LRFS rates of 100% and 97.9% for CF-WBI and 95.6% and 94% for HF-WBI. A short course of radiation therapy seems to be comparable to CF-WBI in terms of clinical outcomes. These data support the use of hypofractionated schedules in DCIS patients, but considering the remaining uncertainties.

Breast Irradiation in Ductal Carcinoma In Situ.

There is strong and consistent evidence that whole breast irradiation after breast conserving surgery significantly decreases the risk of ipsilateral breast events, in situ or invasive, underpinning its established role in patients with ductal carcinoma in situ (DCIS). Pending publication of the full results of BIG 3-07/TROG 07.01 randomised trial, addition of tumour bed boost to whole breast irradiation is recommended in the presence of adverse clinical-pathologic features, and the use of moderately hypofractionated whole breast dose-fractionation schedules is supported. As published data supporting the use of adjuvant partial breast irradiation in patients with low-risk DCIS are limited, its off-study application should be limited to low-risk patients defined by international and national guidelines. Finally, low-risk patients may not derive clinically meaningful benefits from radiation therapy and research on molecular profiling is ongoing to improve prognostic precision and guide safe omission of radiation therapy after breast conserving surgery.

Results of accelerated partial breast irradiation in patients not suitable for external beam irradiation stratified by GEC-ESTRO, ASTRO, and ABS guidelines

PurposeThis study aims to review the outcome of an institution in multicatheter/interstitial accelerated partial breast irradiation (MC-APBI) for treatment of patients with breast cancer, either with strong criteria for APBI or unable to be treated with whole-breast irradiation. The outcomes were also stratified by the American Society for Radiation Oncology, American Brachytherapy Society, and Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology patient selection criteria. MethodsThe study includes 118 patients and 120 MC-APBI treatments, treated in a single tertiary center, between November 2003 and August 2016. The analysis is focused on the clinical baseline characteristics, local control, relapse-free survival, disease-specific survival (DSS), and overall survival. ResultsIn accordance to the American Society for Radiation Oncology, American Brachytherapy Society, and Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology, 17.1% were “unsuitable,” 19.2% were “unacceptable,” and 19.5% were “high risk,” respectively. The main reasons why high-risk patients were submitted to MC-APBI were as follows: cardiopathy (n = 7), social difficulties (n = 4), and mobility limitations (n = 4). At the median followup period of 86.5 months, ipsilateral breast tumor recurrence was observed in one (0.8%) patient. The 3-year and 5-year relapse-free survival were 100% and 99.1%, respectively. DSS was 100%. ConclusionsThis study demonstrated excellent control rates, DFS, and DSS of MC-APBI, rendering APBI as an excellent treatment for patients with breast cancer, even those who are not necessarily eligible for this treatment approach. The selection criteria for ABPI diverge according to different guidelines and are based on studies with discrepancies, making extremely possible that these recommendations could be changed.

Comparison of MRI and CT for Target Volume Delineation and Dose Coverage for Partial Breast Irradiation in Patients with Breast Cancer

Comparison of MRI and CT for Target Volume Delineation and Dose Coverage for Partial Breast Irradiation in Patients with Breast Cancer