Conventional versus hypofractionated postmastectomy radiotherapy: a report on long-term outcomes and late toxicity

Is there any radiation-induced brachial plexopathy after hypofractionated postmastectomy radiotherapy with helical tomotherapy?

Introduction

Radiation-induced brachial plexopathy (RIBP) is one of the most concerning late radiation effects after hypofractionated postmastectomy radiotherapy (HF-PMRT) to the chest wall and regional lymph nodes. The purpose of this study was to investigate the RIBP events occurring in breast cancer patients after HF-PMRT using intensity-modulated radiation therapy (IMRT) by helical tomotherapy. Furthermore, the dosimetric parameters of the ipsilateral brachial plexus were reported.

Materials and methods

Breast cancer patients who underwent HF-PMRT using the IMRT via HT at our institute were included. In the first cohort, subjective RIBP symptoms were measured using a QuickDASH questionnaire, whereas objective RIBP events were assessed using a comprehensive physical evaluation in the second cohort. The ipsilateral brachial plexus from all eligible patients' treatment plans was contoured, and the dosimetric parameters were explored.

Results

From March 2014 to December 2022, 229 patients were enrolled; 107 and 72 individuals were in the first and second cohorts, respectively. The first cohort's median follow-up period was 27 months, and the second cohort was 31 months. In the first cohort, 80 patients (74.77%) had a normal function, 21 (19.63%) had a mild grade, and 6 (5.61%) had a moderate grade; no severe or very severe RIBP was observed. However, the comprehensive physical evaluation of the second cohort indicated no RIBP events. Dosimetric analysis revealed that the median maximum dose was 44.52, 44.52, and 44.60 Gy; the median mean dose was 33.00, 32.23, and 32.33 Gy; and the median dose at 0.03 cc was 44.33, 44.36, and 44.39 Gy for all patients, patients in the first and second cohort, respectively. Each dosimetric parameter was evaluated, and no statistically significant differences were detected.

Conclusion

The absence of RIBP events supports the safety of employing HF-PMRT by HT for the chest wall and all regional lymph nodes. We propose that applying the ICRU Report 83 criteria for IMRT planning, which limit the maximum dose (107% of the prescribed dose) to less than 2% of the planning target volume and exclude the brachial plexus region from the maximal dose area, is a practical way to minimize the risk of RIBP from HF-PMRT.

Long-term treatment results of conventional and hypofractionation radiotherapy in postmastectomy cancer breast patients: A retrospective study from rural cancer center of Maharashtra, India

AIM

This study aims to evaluate the long-term treatment outcome of conventional and hypofractionation radiotherapy in postmastectomy cancer breast patients.

MATERIAL AND METHODS

A total of 140 postmastectomy breast cancer patients were included in this retrospective study, who were treated from 2012 to 2014 with chemotherapy and various fractionation radiotherapy schedules. Radiotherapy treatment records for study group-I received radiotherapy 4256 cGy in 16 fractions over 3½ weeks, group-II patients received 4005 cGy in 15 fractions over 3 weeks, and conventional radiotherapy group-III received 5000 cGy in 25 fractions over 5 weeks.

RESULTS

The median follow-up of patients from all groups was 60 months (range 9 to 111 months). There were 39 cases with disease failure, 13 (26%) in group I (42.56 Gy), 16 (40%) in group II (40.05 Gy), and 10 (20%) in group III (50 Gy). There were 4 locoregional recurrences (LRRs), two isolated, and 11 distant failures in group I, 3 LRRs (1 isolated LRR) and 15 distant failures in group II, and only one LRR and 9 distant failures in group III. The disease-free survival (DFS) were 74%, 60%, and 80%, respectively, in groups I, II, and III (P =0.044).

CONCLUSION

The long-term results of this study show that hypofractionation radiotherapy in postmastectomy cases is well tolerated and acute and late side effects are also comparable to conventional fractionation. In our study, locoregional and distant failure seems slightly higher with hypofractionation schedules than in other studies, highlighting the need for more studies with long-term follow-up in postmastectomy patients.

Significance of Hypofractionated Radiotherapy in Postoperative Irradiation for Breast Cancer: An Asian Multi-institutional Prospective Study

AIMS

There is a need for the adequate distribution of healthcare resources in Southeast Asia. Many countries in the region have more patients with advanced breast cancer who are eligible for postmastectomy radiotherapy (PMRT). Therefore, it is critical that hypofractionated PMRT is effective in most of these patients. This study investigated the significance of postoperative hypofractionated radiotherapy in patients with breast cancer, including advanced breast cancer, in these countries.

MATERIALS AND METHODS

Eighteen facilities in 10 Asian countries participated in this prospective, interventional, single-arm study. The study included two independent regimens: hypofractionated whole-breast irradiation (WBI) for patients who had undergone breast-conserving surgery and hypofractionated PMRT for patients who had undergone total mastectomy at a dose of 43.2 Gy in 16 fractions. In the hypofractionated WBI group, patients with high-grade factors received additional 8.1 Gy boost irradiation sessions for the tumour bed in three fractions.

RESULTS

Between February 2013 and October 2019, 227 and 222 patients were enrolled in the hypofractionated WBI and hypofractionated PMRT groups, respectively. The median follow-up periods in the hypofractionated WBI and hypofractionated PMRT groups were 61 and 60 months, respectively. The 5-year locoregional control rates were 98.9% (95% confidence interval 97.4-100.0) and 96.3% (95% confidence interval 93.2-99.4) in the hypofractionated WBI and hypofractionated PMRT groups, respectively. Regarding adverse events, grade 3 acute dermatitis was observed in 2.2% and 4.9% of patients in the hypofractionated WBI and hypofractionated PMRT groups, respectively. However, no other adverse events were observed.

CONCLUSION

Although further follow-up is required, hypofractionated radiotherapy regimens for postoperative patients with breast cancer in East and Southeast Asian countries are effective and safe. In particular, the proven efficacy of hypofractionated PMRT indicates that more patients with advanced breast cancer can receive appropriate care in these countries. Hypofractionated WBI and hypofractionated PMRT are reasonable approaches that can contain cancer care costs in these countries. Long-term observation is required to validate our findings.

Radiation-induced lung injury after breast cancer treatment: incidence in the CANTO-RT cohort and associated clinical and dosimetric risk factors

Purpose

Radiation-induced lung injury (RILI) is strongly associated with various clinical conditions and dosimetric parameters. Former studies have led to reducing radiotherapy (RT) doses to the lung and have favored the discontinuation of tamoxifen during RT. However, the monocentric design and variability of dosimetric parameters chosen have limited further improvement. The aim of our study was to assess the incidence of RILI in current practice and to determine clinical and dosimetric risk factors associated with RILI occurrence.

Material and methods

Data from 3 out of the 10 top recruiting centers in CANTO-RT, a subset of the CANTO prospective longitudinal cohort (NCT01993498), were retrospectively analyzed for RILI occurrence. This cohort, which recruited invasive cT0-3 cN0-3 M0 breast cancer patients from 2012 to 2018, prospectively recorded the occurrence of adverse events by questionnaires and medical visits at the end of, and up to 60 months after treatment. RILI adverse events were defined in all patients by the association of clinical symptoms and compatible medical imaging.

Results

RILI was found in 38/1565 (2.4%) patients. Grade II RILI represented 15/38 events (39%) and grade III or IV 2/38 events (6%). There were no grade V events. The most frequently used technique for treatment was 3D conformational RT (96%). In univariable analyses, we confirmed the association of RILI occurrence with pulmonary medical history, absence of cardiovascular disease medical history, high pT and pN, chemotherapy use, nodal RT. All dosimetric parameters were highly correlated and had close predictive value. In the multivariable analysis adjusted for chemotherapy use and nodal involvement, pulmonary medical history (OR=3.05, p<0.01) and high V30 Gy (OR=1.06, p=0.04) remained statistically significant risk factors for RILI occurrence. V30 Gy >15% was significantly associated with RILI occurrence in a multivariable analysis (OR=3.07, p=0.03).

Conclusion

Our study confirms the pulmonary safety of breast 3D RT in CANTO-RT. Further analyses with modern radiation therapy techniques such as IMRT are needed. Our results argue in favor of a dose constraint to the ipsilateral lung using V30 Gy not exceeding 15%, especially in patients presenting pulmonary medical history. Pulmonary disease records should be taken into account for RT planning.

A phase II randomized clinical trial to assess toxicity and quality of life of breast cancer patients with hypofractionated versus conventional fractionation radiotherapy with regional nodal irradiation in the context of COVID-19 crisis

Purpose

This study, conducted during the COVID-19 crisis, primarily aimed to compare the acute toxicity between conventional fractionated radiation therapy (CF-RT) with hypofractionated radiation therapy (HF-RT) among patients who underwent breast-conserving surgery or mastectomy in whom breast or chest wall and regional nodal irradiation (RNI) were indicated. The secondary endpoints were both acute and subacute toxicity, cosmesis, quality of life, and lymphedema features.

Methods

In this open and non-inferiority randomized trial, patients (n = 86) were randomly allocated 2:1 in the CF-RT arm (n = 33; 50 Gy/25 fractions ± sequential boost [10 Gy/5 fractions]) versus the HF-RT arm (n = 53; 40 Gy/15 fractions ± concomitant boost [8 Gy/15 fractions]). Toxic effects and cosmesis evaluation used the Common Terminology Criteria for Adverse Events, version 4.03 (CTCAE) and the Harvard/National Surgical Adjuvant Breast and Bowel Project (NSABP)/Radiation Therapy Oncology Group (RTOG) scale. For the patient-reported quality of life (QoL), the European Organisation for Research and Treatment of Cancer quality of life questionnaire (EORTC QLQ-C30) and the breast cancer-specific supplementary questionnaire (QLQ-BR23) were used. Lymphedema was assessed by comparing volume differences between the affected and contralateral arms using the Casley-Smith formula.

Results

Grade 2 and grade 3 dermatitis were lower with HF-RT than with CF-RT (28% vs. 52%, and 0% vs. 6%, respectively; p = 0.022). HF-RT had a lower rate of grade 2 hyperpigmentation (23% vs. 55%; p = 0.005), compared to CF-RT. No other differences in overall rates of physician-assessed grade 2 or higher and grade 3 or higher acute toxicity between HF-RT and CF-RT were registered. There was no statistical difference between groups regarding cosmesis, lymphedema rate (13% vs. 12% HF-RT vs. CF-RT; p = 1.000), and functional and symptom scales, during both the irradiation period and after 6 months of the end of treatment. The results revealed that the subset of patients up to 65 years or older did not show a statistical difference between both arm fractionation schedules (p > 0.05) regarding skin rash, fibrosis, and lymphedema.

Conclusion

HF-RT was non-inferior to CF-RT, and moderate hypofractionation showed lower rates of acute toxicity, with no changes in quality-of-life outcomes.

Clinical trial registration

ClinicalTrials.gov, identifier NCT40155531.

Single pulse protoacoustic range verification using a clinical synchrocyclotron

Objective.Proton therapy as the next generation radiation-based cancer therapy offers dominant advantages over conventional radiation therapy due to the utilization of the Bragg peak; however, range uncertainty in beam delivery substantially mitigates the advantages of proton therapy. This work reports using protoacoustic measurements to determine the location of proton Bragg peak deposition within a water phantom in real time during beam delivery.Approach.In protoacoustics, proton beams have a definitive range, depositing a majority of the dose at the Bragg peak; this dose is then converted to heat. The resulting thermoelastic expansion generates a 3D acoustic wave, which can be detected by acoustic detectors to localize the Bragg peak.Main results.Protoacoustic measurements were performed with a synchrocyclotron proton machine over the exhaustive energy range from 45.5 to 227.15 MeV in clinic. It was found that the amplitude of the acoustic waves is proportional to proton dose deposition, and therefore encodes dosimetric information. With the guidance of protoacoustics, each individual proton beam (7 pC/pulse) can be directly visualized with sub-millimeter (<0.7 mm) resolution using single beam pulse for the first time.Significance.The ability to localize the Bragg peak in real-time and obtain acoustic signals proportional to dose within tumors could enable precision proton therapy and hope to progress towardsin vivomeasurements.

Hypofractionated radiotherapy in postmastectomy locally advanced breast cancer: an interim report on acute toxicities and dosimetry

Background

There is a growing interest in the use of hypofractionation in the setting of post-mastectomy radiation therapy (PMRT). Here, we present an interim report on the acute toxicities and the dosimetry of a 15-day hypofractionated regimen.

Materials and methods

Patients aged 18-75 years who underwent mastectomy and had pathological stage IIB-IIIC or any clinical stage who had received neoadjuvant chemotherapy were treated with PMRT at a dose of 43.5 Gy in 15 fractions. Acute toxicities were scored using Common Terminology Criteria for Adverse Events (CTCAE) version 4.0.

Results

Between September 2020 and September 2021, 92 patients were enrolled in the study. Majority experienced grade 1 dermatitis during the course of treatment. Skin toxicities peaked two weeks after PMRT in which 57 patients (62%) had grade 2 dermatitis and 6 patients (7%) had grade 3 dermatitis. Most resolved one month after treatment, with all resolving at three months. Grade 2 fatigue occurred in 4 patients (4%). There were no grade 3 fatigue or pneumonitis of any grade. The average V95% for the chest wall, axilla, and supraclavicular fossa were 91.5%, 99.3%, and 97.5%, respectively. Average ipsilateral lung V17 was 43.6%, while the mean heart dose averaged at 3.46 Gy.

Conclusion

This interim report showed that hypofractionated PMRT is associated with a low incidence of clinically significant acute toxicities. With the use of the 3-dimensional conformal radiotherapy technique and volume-based planning, adequate target volume coverage and acceptable heart doses were achieved, although with a slightly higher ipsilateral lung dose.

Evaluation of the Effect of Axillary Radiotherapy Dose and the Development of Lymphedema in Breast Cancer Patients

Purpose

The present study is aiming to correlate different radiotherapy techniques, fractionations, and doses received by each axillary LN level and axillary vessels with the development of breast cancer-related lymphedema (BCRL).

Methods and Materials

We retrospectively studied 181 female breast cancer patients who were diagnosed and treated by radiation therapy during the period from January 2012 to December 2017. The radiotherapy treatment plans were recalled from the archives. The axillary LN levels I, II, III, supraclavicular LN were contoured as well as axillary vessels. New dose volume histograms were generated to correlate between the radiotherapy dose t and the development of BCRL.

Results

The study included 162 patients treated with a 3D radiotherapy technique and 19 treated with a 2D radiotherapy technique; 124 patients underwent MRM, while 57 patients underwent BCS; 117 patients were treated with a hypofractionated technique, while 64 patients were treated with a conventional radiotherapy technique. The cumulative incidence of BCRL after radiotherapy was 20.4%. There was a statistically significant relationship between the 2D radiotherapy technique compared with 3DCRT and development of lymphedema (55 vs. 16.6, respectively; p < 0.001). Patients who were treated with conventional radiotherapy had significantly higher rates of lymphedema (42.2%) compared with hypofractionated radiotherapy (8.5%) (p < 0.001). There was a non-significant relationship between mean radiotherapy dose to axillary levels or axillary vessels and development of lymphedema.

Conclusion

Breast cancer radiotherapy with the 2D technique and conventional fractionation protocol might increase the risk of BCRL. No correlation was observed between radiotherapy dose to each axillary LN level, axillary vessels and BCRL.

Outcomes and toxicity following post-operative hypofractionated radiotherapy to the regional nodes and the breast or the chest wall in locally advanced breast cancer

Objectives:

We aimed to analyze the impact of a 3-week schedule of HypoFractionated (HF) radiotherapy (RT) after axillary dissection and breast surgery, in terms of safety and efficacy in patients with locally advanced breast cancer (BC).

Methods:

Eligible patients were females with Stage IIA – IIIC BC who underwent axillary dissection and breast surgery, either quadrantectomy or mastectomy. HF RT was delivered in 15 or 16 fractions for a total dose of 40.05 Gy or 42.56 Gy, respectively, to the clavicular nodal region along with the whole breast (HF WBRT) or the chest wall (HF PMRT), according to the type of surgery. Locoregional recurrence (LRR), distant metastases-free survival (DMFS), overall survival (OS) and acute and late treatment-related toxicities were estimated.

Results:

57 patients with a median age of 60 years (32–85) were retrospectively analyzed. 34 (60%) of patients underwent breast conservative surgery in the form of quadrantectomy and 23 (40%) were offered radical mastectomy. All patients underwent hypofractionated regional nodal irradiation (HF RNI). 34 (60%) of them underwent HF WBRT, while 23 (40%) received HF PMRT. At a median follow-up of 80 months (30–113), the 7-year LRR-free survival was 93% (95% CI, 74%–95%). The same features for DMFS and OS were 76% (95% CI, 52%–78%) and 67% (95% CI, 50%–80%), respectively. Only one (2%) patient experienced G3 acute skin toxicity. No grade ≥2 late toxicity was observed.

Conclusion:

Our study shows that HF RNI with HF RT to the whole breast or the chest wall after breast surgery is safe and effective in patients with locally advanced BC. Longer follow-up is needed to strengthen further analyses on late toxicity and clinical outcomes.

Advances in knowledge:

This paper adds to the evidence that post-operative RNI with WBRT or PMRT can be safely and effectively delivered with 3-week HF regimen. Locally advanced BC patients can be offered HF RT to the regional nodes and the breast or the chest wall regardless the type of surgery.

Breast Cancer Management During the COVID-19 Pandemic: the Radiation Oncology Perspective

Purpose of Review

The coronavirus disease 19 (COVID-19) pandemic has caused disruption in healthcare throughout the world. The limitations placed on hospital resources and the need to limit potential exposure to SARS-CoV-2 for both patients and healthcare staff have affected oncologic care for patients with breast cancer (BC), including radiation therapy (RT). This review highlights published guidelines regarding the provision of radiotherapy for BC patients and their adoption by radiation oncology centers.

Recent Findings

Multiple international and national consortiums plus select institutions have published formal recommendations regarding radiation therapy for BC during the COVID-19 pandemic. They embody the principles of limiting in-person visits, proper triage, and the judicious use of delay, abbreviation, or omission of RT as appropriate.

Summary

Since the start of the pandemic, multiple publications have provided guidance regarding RT for BC during this challenging time. The pandemic has led to increased use of telemedicine and abbreviated radiation therapy courses in the setting of BC, which are likely to persist. Future research is needed to establish the effect of these changes on oncologic outcomes.

Radiation Therapy for Breast Cancer During the COVID-19 Pandemic in Low Resource Countries: Consensus Statement from the Iranian Society of Radiation Oncology

Context: COVID-19 pandemic has resulted in considerable overloading of health care systems in almost all regions of the world. Among different malignancies, breast cancer can be considered as a typical example of how the decision-making process for radiation treatment can be adapted to unusual situations. There exist several international guidelines in order to modify radiotherapy treatments during the COVID-19 pandemic, however, some of their recommendations are not applicable in regions with limited resources. In this manuscript, we provided guidance to deliver radiotherapy to patients with breast cancer during the COVID-19 pandemic based on our available nationwide resources. Evidence Acquisition: A team of expert radiation oncologists convened multidisciplinary and cross-institutional meetings and reviewed the major internationally published guidelines and relevant literature in the field of breast radiotherapy during the COVID-19 pandemic in order to establish recommendations for the safe application of radiation regimens based on the national limited resources. Results: Practical guidance in order to deliver radiotherapy to patients with breast cancer during the COVID-19 pandemic based on available nationwide resources was developed. Conclusions: Many of the international recommendations on the breast cancer radiotherapy during COVID-19 outbreak are not applicable in countries with limited resources. Therefore, modifying the guidelines based on the available resources is mandatory in order to achieve the best possible results.

Real-World Practice of Hypofractionated Radiotherapy in Patients With Invasive Breast Cancer

Purpose

Application of hypofractionated radiotherapy (HFRT) is growing in patients with breast cancer (BC). This study aimed to explore a real-world practice of HFRT in early and locally advanced BC.

Methods

Patients with invasive BC between 2015 and 2019 were retrospectively reviewed. Radiotherapy (RT) was delivered by HFRT and conventionally fractionated radiotherapy (CFRT). Locoregional recurrence-free survival (LRRFS) and disease-free survival (DFS) were calculated by Kaplan–Meier curve and compared by Log-rank test. The effect of treatment modality on DFS was estimated by univariate and multivariable analyses.

Results

A total of 1,010 patients were included in this study, and 903 (89.4%) were treated with HFRT. At a median follow-up of 49.5 months, there was no significant difference in a 4-year cumulative incidence of LRRFS in HFRT group (1.5%) and in CFRT group (3.8%) (p = 0.23), neither in different nodal stages nor in N2–3 patients with different molecular subtypes. The 4-year DFS was 93.5% in HFRT group compared with 89.9% in CFRT group with no significant difference either (p = 0.17). Univariate and multivariable analyses also showed no significant difference in DFS between HFRT and CFRT group. However, DFS of HFRT group tended to be lower in N2–3 patients with triple negative BC compared with that of CFRT group (76.2% versus 100%).

Conclusion

HFRT can achieve similar cumulative incidence of LRRFS and DFS in patients with BC after lumpectomy or mastectomy, and also in different nodal stage, and in locally advanced stage with different molecular subtypes.

Accelerated radiotherapy in patients over sixty years old after mastectomy: Acute and one-year physician-assessed toxicity and health-related quality of life

INTRODUCTION

Postmastectomy radiotherapy reduces the risk of locoregional recurrence in breast cancer patients. The first results on accelerated radiotherapy in five fractions after breast conserving surgery are promising. The data on postmastectomy radiotherapy in five or six fractions is limited. We now present the data on acute and one-year toxicity and health related quality of life (HRQoL) after postmastectomy radiotherapy in patients of sixty years or older.

METHODOLOGY

119 patients received five fractions of 5.7 Gy to the chest wall and five fractions of 5.4 Gy to the lymph nodes over ten to twelve days. Physician-assessed toxicity were scored using the Common Terminology Criteria for Adverse Events version 4.03 toxicity scoring system and the LENT-SOMA scale. Fatigue was measured by the Multidimensional Fatigue Inventory (MFI-206). HRQoL was assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire the breast cancer specific module and the BREAST-Q questionnaire.

RESULTS

Fatigue and edema were the most frequently observed physician-assessed toxicities. One year after radiotherapy only 12.9% experienced a clinically important deterioration in chest wall symptoms and in 22.9% of the patients were improved. Future perspective at one year after radiotherapy was improved in 40.0% of the patients. Patient-reported fatigue showed the greatest improvement.

CONCLUSION

Accelerated radiotherapy should be considered to minimize the burden of breast cancer treatment, especially in older patients.

Ten-year outcomes of hypofractionated postmastectomy radiation therapy of 26 Gy in 6 fractions

PURPOSE

To investigate the efficacy and long-term side effects of hypofractionated postmastectomy radiation therapy (HFRT-PM) of 26 Gy in 6 fractions over 5 weeks.

MATERIALS & METHODS

We retrospectively reviewed characteristics and outcomes of patients with stage I-III breast cancer treated with HFRT-PM between 2000-2009. Treatment provided four fractions of 4 Gy (day (d)1, d3, d15, d17) then two fractions of 5 Gy (d29, d31) over 5 weeks. The treatment techniques were applied by using 3D conformal radiotherapy of chest wall with regional nodal volume if required.

RESULTS

454 patients were identified, with a median follow-up of 10.6 years (range 0.5-22.9). Regional nodal irradiation was made in 84.1 % of patients. At 10 years, the cumulative incidence of locoregional relapse was 15.1 %. In multivariate analysis, regional lymph nodes involvement (≥ 4 nodes) was associated with worse locoregional control (HR 1.68; [95% CI 1.06-2.67], p = 0.03) and overall survival (HR 2.16; [95% CI 1.59-2.95], p < 0.001). The toxicities were acceptable. The incidence of cardiac disorders (3.3 %), and symptomatic lung fibrosis (1.5 %) was low during follow-up. At 10 years, the cumulative rate of arm lymphedema was 9.5 % and considered severe in 20 patients (4.4 %).

CONCLUSION

The long-term results of this study show that HFRT-PM of 26 Gy in 6 fractions over 5 weeks seems safes but locoregional recurrence seems slightly higher than those observed in the literature, highlighting that long-term follow-up is needed and the need of randomized trials for hypofractionated radiotherapy therapy in postmastectomy situation.

Accelerated hypofractionated radiotherapy for chest wall and nodal irradiation using hybrid techniques

Aim:

This study compares three different hybrid plans, for left-sided chest wall (CW) and nodal stations irradiation using a hypofractionated dose regimen.

Materials and methods:

Planning target volumes (PTVs) of 25 breast cancer patients that included CW, supraclavicular (SCL) and internal mammary node (IMN) were planned with 3 different hybrid techniques: 3DCRT+IMRT, 3DCRT+VMAT and IMRT+VMAT. All hybrid plans were generated with a hypofractionated dose prescription of 40·5 Gy in 15 fractions. Seventy per cent of the dose was planned with the base-dose component and remaining 30% of the dose was planned with the hybrid component. All plans were evaluated based on the PTVs and organs at risk (OARs) dosimetric parameters.

Results:

The results for PTVs parameters have shown that the 3DCRT+IMRT and 3DCRT+VMAT plans were superior in uniformity index to the IMRT+VMAT plan. The OARs dose parameters were comparable between hybrid plans. The IMRT+VMAT plan provided a larger low dose volume spread to the heart and ipsilateral lung (p < 0·001). The 3DCRT+VMAT plan required less monitor units and treatment time (p = 0·005) than other plans.

Conclusion:

The 3DCRT+VMAT hybrid plan showed superior results with efficient treatment delivery and provide clinical benefit by reducing both low and high dose levels.

Hypofractionated radiotherapy in ten fractions for postmastectomy patients: a phase II study compared with another hypofractionation schedule with sixteen fractions

Background

The purpose of this phase II study was to evaluate the feasibility of hypofractionated radiotherapy (HFRT) with a dose of 36.5 Gy in 10 fractions in postmastectomy patients.

Methods

From March 2014 to December 2015, 85 patients with locally advanced breast cancer were eligible to participate in this study with a schedule of 36.5 Gy in 10 fractions. Intensity-modulated radiation therapy (IMRT) was delivered to the chest wall with or without the supraclavicular region. The primary endpoint was radiation-related toxicities. The secondary endpoints were locoregional failure-free survival (LRFFS), disease-free survival (DFS) and overall survival (OS). And the outcomes were compared with our retrospective study of 72 patients with 42.5 Gy in 16 fractions.

Results

The median follow-up was 69.0 (range 66.5-71.5) months in the 36.5 Gy group and 93.0 (range 91.9-94.1) months in the 42.5 Gy group, respectively. Radiation-related toxicities were mainly grade 1, although a few patients had grade 2 plexopathy (1.2%) and acute skin toxicity (1.2%) in the 36.5 Gy group, and grade 2 acute skin toxicity (5.6%) and lymphedema (4.2%) in the 42.5 Gy group. There were no significant differences between the groups in acute and late toxicities. For all the patients, the 5-year LRFFS, DFS and OS were 97.7 and 100.0%, 93.1 and 90.3%, 98.8 and 97.2%, respectively, without significant differences between the groups.

Conclusion

Postmastectomy HFRT with a schedule of 36.5 Gy in 10 fractions was feasible, with mild toxicities and excellent 5-year clinical outcome.

Trial registration

Trial registration number: ChiCTR-ONRC-14004391.

Date of registration: 9/3/2014.

Cost-effectiveness of postmastectomy hypofractionated radiation therapy vs conventional fractionated radiation therapy for high-risk breast cancer

Background

The phase 3 NCT00793962 trial demonstrated that postmastectomy hypofractionated radiation therapy (HFRT) was noninferior to conventional fractionated radiation therapy (CFRT) in patients with high-risk breast cancer. This study assessed the cost-effectiveness of postmastectomy HFRT vs CFRT based on the NCT00793962 trial.

Methods

A Markov model was adopted to synthesize the medical costs and health benefits of patients with high-risk breast cancer based on data from the NCT00793962 trial. Main outcomes were discounted lifetime costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER). We employed a time-dependent horizon from Chinese, French and USA payer perspectives. Model robustness was evaluated with one-way and probabilistic sensitivity analyses.

Results

Patients receiving CFRT versus HFRT gained an incremental 0.0163 QALYs, 0.0118 QALYs and 0.0028 QALYs; meanwhile an incremental cost of $2351.92, $4978.34 and $8812.70 from Chinese, French and USA payer perspectives, respectively. Thus CFRT versus HFRT yielded an ICER of $144,281.47, $420,636.10 and $3,187,955.76 per QALY from Chinese, French and USA payer perspectives, respectively. HFRT could maintain a trend of >50% probabilities of cost-effectiveness below a willingness-to-pay (WTP) of $178,882.00 in China, while HFRT was dominant relative to CFRT, regardless of the WTP values in France and the USA. Sensitivity analyses indicated that the ICERs were most sensitive to the parameters of overall survival after radiotherapy.

Conclusions

Postmastectomy HFRT could be used as a cost-effective substitute for CFRT in patients with high-risk breast cancer and should be considered in appropriately selected patients.

•

HFRT is a cost-effective substitute for CFRT for women with high-risk breast cancer.

•

The incremental cost-effectiveness ratio varied in a time-dependent manner and increased with the time horizon.

•

Overall survival were the most influential parameter on the incremental cost-effectiveness ratio.

Hypofractionated radiation therapy for breast cancer: Preferences amongst radiation oncologists in Europe - Results from an international survey

BACKGROUND AND PURPOSE

We aimed to assess the prescription preference about hypofractionated radiation therapy (HFRT) for breast cancer (BC) patients amongst radiation oncologists (ROs) practicing in Europe and to identify restraints on HFRT utilisation.

MATERIALS AND METHODS

An online survey was circulated amongst ROs in Europe through personal, RO and BC societies' networks, from October 2019 to March 2020. The statistical analyses included descriptive statistics, chi-squared testing, and logistic regression analysis.

RESULTS

We received 412 responses from 44 countries. HFRT was chosen as the preferred schedule for whole breast irradiation (WBI) by 54.7% and for WBI with regional nodes irradiation (RNI) by 28.7% of the responding ROs. In the case of postmastectomy RT with or without reconstruction, HFRT was preferred by 21.1% and 29.6%, respectively. Overall, 69.2% of the responding ROs selected at least one factor influencing the decision to utilise HFRT, the most frequent of which included age (51.4%), RNI (46.9%), internal mammary lymph nodes irradiation (39.7%), BC stage (33.5%) and implant-based breast reconstruction (31.6%). ROs working in academic centres (odds ratio, (OR), 1.7; 95% confidence interval, (CI); 1.1-2.6, p = 0.019), practicing in Western Europe (OR, 4.2; 95%CI; 2.7-6.6, p < 0.0005) and/or dedicating >50% of clinical time to BC patients (OR, 2.5; 95%CI; 1.5-4.2, p = 0.001) more likely preferred HFRT.

CONCLUSION

Although HFRT is recognised as a new standard, its implementation in routine RT clinical practice across Europe varies for numerous reasons. Better dissemination of evidence-based recommendations is advised to improve the level of awareness about this clinical indication.

Breast Radiation Therapy Under COVID-19 Pandemic Resource Constraints-Approaches to Defer or Shorten Treatment From a Comprehensive Cancer Center in the United States

Purpose

Breast radiation therapy accounts for a significant proportion of patient volume in contemporary radiation oncology practice. In the setting of anticipated resource constraints and widespread community infection with SARS-CoV-2 during the COVID-19 pandemic, measures for balancing both infectious and oncologic risk among patients and providers must be carefully considered. Here, we present evidence-based guidelines for omitting or abbreviating breast cancer radiation therapy, where appropriate, in an effort to mitigate risk to patients and optimize resource utilization.

Methods and Materials

Multidisciplinary breast cancer experts at a high-volume comprehensive cancer center convened contingency planning meetings over the early days of the COVID-19 pandemic to review the relevant literature and establish recommendations for the application of hypofractionated and abbreviated breast radiation regimens.

Results

Substantial evidence exists to support omitting radiation among certain favorable risk subgroups of patients with breast cancer and for abbreviating or accelerating regimens among others. For those who require either whole-breast or postmastectomy radiation, with or without coverage of the regional lymph nodes, a growing body of literature supports various hypofractionated approaches that appear safe and effective.

Conclusions

In the setting of a public health emergency with the potential to strain critical healthcare resources and place patients at risk of infection, the parsimonious application of breast radiation therapy may alleviate a significant clinical burden without compromising long-term oncologic outcomes. The judicious and personalized use of immature study data may be warranted in the setting of a competing mortality risk from this widespread pandemic.

Recent advances in radiotherapy of breast cancer

Radiation therapy is an integral part of the multidisciplinary management of breast cancer. Regional lymph node irradiation in younger trials seems to provide superior target coverage as well as a reduction in long-term toxicity resulting in a small benefit in the overall survival rate. For partial breast irradiation there are now two large trials available which support the role of partial breast irradiation in low risk breast cancer patients. Multiple randomized trials have established that a sequentially applied dose to the tumor bed improves local control with the cost of worse cosmetic results.

Three-dimensional surface imaging in breast cancer: a new tool for clinical studies?

Background

Three-dimensional Surface Imaging (3DSI) is a well-established method to objectively monitor morphological changes in the female breast in the field of plastic surgery. In contrast, in radiation oncology we are still missing effective tools, which can objectively and reproducibly assess and document adverse events in breast cancer radiotherapy within the framework of clinical studies. The aim of the present study was to apply structured-light technology as a non-invasive and objective approach for the documentation of cosmetic outcome and early effects of breast radiotherapy as a proof of principle.

Methods

Weekly 3DSI images of patients receiving either conventionally fractionated radiation treatment (CF-RT) or hypofractionated radiation treatment (HF-RT) were acquired during the radiotherapy treatment and clinical follow-up. The portable Artec Eva scanner (Artec 3D Inc., Luxembourg) recorded 3D surface images for the analysis of breast volumes and changes in skin appearance. Statistical analysis compared the impact of the two different fractionation regimens and the differences between the treated and the contralateral healthy breast.

Results

Overall, 38 patients and a total of 214 breast imaging sessions were analysed. Patients receiving CF-RT showed a significantly higher frequency of breast erythema compared to HF-RT (93.3% versus 34.8%, p = 0.003) during all observed imaging sessions. Moreover, we found a statistically significant (p < 0.05) volumetric increase of the treated breast of the entire cohort between baseline (379 ± 196 mL) and follow-up imaging at 3 months (437 ± 224 mL), as well as from week 3 of radiotherapy (391 ± 198 mL) to follow-up imaging. In both subgroups of patients undergoing either CF-RT or HF-RT, there was a statistically significant increase (p < 0.05) in breast volumes between baseline and 3 months follow-up. There were no statistically significant skin or volumetric changes of the untreated healthy breasts.

Conclusions

This is the first study utilizing 3D structured-light technology as a non-invasive and objective approach for the documentation of patients receiving breast radiotherapy. 3DSI offers potential as a non-invasive tool to objectively and precisely monitor the female breast in a radiooncological setting, allowing clinicians to objectively distinguish outcomes of different therapy modalities.