Fractionation for Whole Breast Irradiation: An American Society for Radiation Oncology (ASTRO) Evidence-Based Guideline

Impact of Consensus Guidelines, Clinical Trials, and COVID-19 on Fractionation Practices for Node-negative Intact Breast Cancer

OBJECTIVE

To evaluate whether hypofractionated radiotherapy (HF-RT) in node-negative intact breast cancer significantly increased after guideline updates, trial publications, and COVID-19.

METHODS

Patients with node-negative breast cancer undergoing lumpectomy and adjuvant RT were identified in the National Cancer Database. Receiving ≥25 and <50 Gy in 5-20 fractions defined HF-RT. Receiving 50 to 66 Gy in >20 fractions defined conventional RT (CF-RT). Patient characteristics were compared with X2 testing. Joinpoint analysis identified when fractionation significantly changed. Variables associated with HF-RT were identified by univariate and multivariate (MVA) logistic regression. Two-sided P-value <0.05 was significant.

RESULTS

Patients meeting criteria totaled 236,336; 54.8% received CF-RT and 45.2% HF-RT. HF-RT and 5-fraction RT significantly increased after 2015 and 2019, respectively (P<0.05). On MVA, HF-RT was positively associated with: age older than or equal to 65 years (OR 2.14, P<0.001); private insurance (OR 1.27, P=0.03); treatment in Midwest (OR 1.66, P<0.001) or Western United States (US) (OR 3.77, P<0.001); distance ≥50 miles (OR 1.16, P=0.001); later year of diagnosis (OR 1.44, P<0.001); and partial breast irradiation (OR 2.08, P<0.001). HF-RT was negatively associated with: community (OR 0.49, P<0.001) or integrated network (0.55, P<0.001) centers; grade 2 (OR 0.83, P<0.001) or 3 (OR 0.49, P<0.001), hormone receptor negative (OR 0.66, P<0.001), and HER2+ (OR 0.74, P<0.001) disease; positive surgical margins (OR 0.61, P<0.001); and presence of lympho-vascular invasion (OR 0.86, P<0.001).

CONCLUSIONS

HF-RT in node-negative intact breast cancer increased after 2015, coinciding with US and European guideline updates. Five-fraction RT increased after 2019, coinciding with COVID-19 and FAST-Forward trial results.

Update on the management of ductal carcinoma in situ of the breast: current approach and future perspectives

The standard treatment for ductal carcinoma in situ became well established through the results of several valuable clinical trials, and its therapeutic benefits have now come to be taken for granted. Ductal carcinoma in situ has an extremely good prognosis with the current treatment approach, with a 10-year breast cancer-specific survival rate of 97-98%. According to one retrospective cohort study, the breast cancer-specific survival rate of patients with low-grade ductal carcinoma in situ does not differ significantly between patients undergoing and not undergoing surgery. Some patients with ductal carcinoma in situ are not at a risk of progression to invasive cancer, but the predictors of such progression have not yet been clearly identified. Therefore, the same therapeutic strategies have been used to treat ductal carcinoma in situ and under the assumption that they have risks of invasive breast cancer, and a well-balanced risk/benefit ratio in respect of treatment has not yet been achieved. Based on the results of several recent clinical trials aimed at ensuring provision of a well-balanced treatment for patients with ductal carcinoma in situ which carries a good prognosis, de-escalation of postoperative adjuvant therapy has now begun. Currently, not only is the optimization of postoperative adjuvant therapy accelerating, but also clinical trials to de-escalate basic surgical treatments are under way. There is a possibility of achieving individualized treatment for patients with ductal carcinoma in situ of the breast with reduced treatment intervention. In this review, we present an overview of the current treatment approaches and potential future management strategies for ductal carcinoma in situ of the breast.

Geriatric determinants of curative radiotherapy scheme choice for older adults with breast cancer treatment compliance and tolerance: Results from the GERABEL study

INTRODUCTION

Chronological and functional aging complicates care in older patients, and therapeutic decisions need to consider individual needs to minimise morbidity and mortality. Therapeutic decisions should be guided by a multidisciplinary geriatric assessment, allowing a complete assessment of physical and functional performance. In this context, the GERABEL study aimed to orientate the irradiation strategy based on a detailed oncogeriatric assessment in women more than 70 years old with breast cancer.

MATERIALS AND METHODS

This was a multicentre clinical trial conducted between January 2017 and June 2021. The oncogeriatric assessment comprised seven questionnaires (activities of daily living [ADL], instrumental ADL, Mini-Mental State Examination, mini Geriatric Depression Scale, Mini-Nutritional Assessment, Cumulative Illness Rating Scale-Geriatric, and Timed Up and Go) to determine a predictive score. Irradiation regimen was assigned according to oncogeriatric score: normofractionated - NF (score range, 160-200), hypofractionated - HF (score range, 159-120), or high-dose hypofractionated - HDHF (score ≤ 119). Endpoints were the overall tolerance to treatment, using the oncogeriatric score as a proxy at six months post-treatment, and compliance.

RESULTS

After oncogeriatric assessment at baseline, 177 patients were treated with a NF regimen, 24 with a HF regimen, and four with a HDHF regimen. Tolerance was excellent in the three groups, as no decrease of more than 20 % in the oncogeriatric score was noted at six months post-treatment. More generally, 68 % and 73 % of patients reported an improvement of the oncogeriatric score at two months and six months post-treatment, respectively. Only four treatment interruptions were observed and quality-of-life was well-conserved. In the hypo fractionated groups, short-term toxicities were not increased and no impact was noted on compliance.

DISCUSSION

Decision-making guidance for irradiation schemes in breast cancer according to oncogeriatric determinants was successful in older patients, who tolerated treatment well and, overall, had a preserved general condition.

Early-Stage Breast Cancer: A Critical Review of Current and Emerging Practice

Breast-conserving surgery followed by adjuvant radiation to reduce the risk of ipsilateral breast tumor recurrence is the mainstay of treatment for early-stage breast cancer (ESBC). However, improved understanding of the heterogeneity of the clinical and molecular characteristics of ESBC has led to greater efforts to personalize approaches to treatment. Furthermore, advances in the understanding of the radiobiology of breast cancer have led to several practice-changing trials on the effectiveness and tolerability of moderate and ultrahypofractionated radiation. Here, we review the recent evidence and ongoing research in the radiotherapeutic management of ESBC, including the use of boost for high-risk disease and opportunities for accelerated fractionation, partial breast irradiation, and radiation omission for low-risk disease. We also discuss how molecular profiling can inform decision-making and new opportunities for primary radiation therapy and reirradiation.

Magnetic resonance imaging-guided single-fraction preoperative radiotherapy for early-stage breast cancer (the RICE trial): feasibility study

BACKGROUND

Over the past decade, the adoption of screening programs, digital mammography, and magnetic resonance imaging (MRI) has increased early-stage breast cancer diagnosis rates. Mortality rates have decreased due to early detection and improved treatments, including personalized therapies. Accelerated partial-breast irradiation (APBI) is emerging as a convenient and effective treatment for some patients, with studies exploring its preoperative use. Preoperative APBI, especially with MRI guidance, offers improved tumor targeting and potentially reduced side effects. Magnetic Resonance Imaging-Guided Single-Fraction Pre-Operative Radiotherapy for Early-Stage Breast Cancer (RICE trial) aims to assess the feasibility and efficacy of MRI-guided single-dose radiotherapy (RT) for early-stage breast cancer.

METHODS

The RICE study is a prospective, single-arm study evaluating single-fraction preoperative, APBI treatment for patients with early-stage breast cancer using a magnetic resonance imaging linear accelerator (MRI linac). Eligible patients enrolled in this study will have a core biopsy to confirm estrogen receptor-positive and HER2-negative sub-type. RT planning will use a planning computed tomography (CT) co-registered with a MRI with the patient in either the supine or prone position. For the diagnostic workup, [18F] fluorodeoxyglucose positron emission tomography/CT ([18F] FDG PET/CT) and [18F] fluoroestradiol positron emission tomography/CT ([18F] FES PET/CT) will be performed prior to treatment. Thirty patients will receive a single ablative RT dose of 21 Gray to the tumor. Pre-treatment and post-treatment MRI scans will be acquired at baseline and 5 weeks post-RT respectively. Breast-conserving surgery will be scheduled for 6 weeks after APBI treatment using the MRI linac. The primary study endpoint is the successful administration of a single fraction of preoperative breast RT under the guidance of an MRI linac. Secondary endpoints include evaluating the utility of MRI, [18F] FDG PET/CT, and [18F] FES PET/CT as a non-invasive method for assessing treatment response in patients undergoing single-fraction preoperative APBI.

CONCLUSION

The RICE trial represents a significant step in breast cancer treatment, offering insights that could lead to treatment protocols with minimized RT appointments and enhanced patient outcomes.

TRIAL REGISTRATION

This trial is registered with the Australian New Zealand Clinical Trials Registry (ANZCTR). Registered 31st of May 2021.

REGISTRATION NUMBER

ACTRN12621000659808 .

Breast Cancer Adjuvant Radiotherapy and Chemotherapy Sequencing: Sequential, Concomitant, or What Else? A Comprehensive Review of the Adjuvant Combinations Journey

Background: To date, in breast cancer (BC) treatment, adjuvant chemotherapy (A-CT) has preceded adjuvant radiotherapy (A-RT). In the last twenty years, the adjuvant treatment of BC has quickly evolved due to better knowledge of its molecular biology, genetic profile, and α/β ratio of 3/4 Gy for tumor and normal tissue radiosensitivity. Thus, new schedules with hypofractionated radiotherapy have been tested, and a third generation of A-CT has been introduced, raising the question of whether it is time to rethink the sequencing between these two approaches. Methods: In the last 20 years, many attempts have been made worldwide to optimize the best sequencing strategy between these two approaches in terms of sequential CT-RT and RT-CT and concomitant and sandwich modalities using drugs and schedules. This paper presents a comprehensive review of the state of the art, analyzing all the available studies to assess the sequencing between A-CT and A-RT with different generations of chemotherapy schedules. Results: More than 8000 patients from 30 studies treated with adjuvant chemotherapy and whole breast radiotherapy who were enrolled in randomized, retrospective, and prospective studies were analyzed. Sequential, concomitant, and sandwich modalities of chemotherapy with conventional or hypofractionated RT schedules from the most important studies were included. The most used sequence was adjuvant chemotherapy followed by conventional or hypofractionated radiotherapy. In the concomitant approach, i.v. CMF has been the most important adopted schedule, while the concomitant use of anthracyclines and taxanes with conventional or hypofractionated radiotherapy has been found to be more toxic. One study analyzed the benefit in terms of reducing adjuvant treatment time with upfront hypofractionated radiotherapy and third-generation chemotherapy. Conclusions: At present, the best sequencing strategy has not yet been defined. This comprehensive review is a journey among the most important randomized, retrospective, and prospective studies that highlights the past, current, and novel time sequencing proposals between A-CT and A-RT to assess the state of the art and provide useful information for future adjuvant approaches in breast cancer treatment.

Increase in Hypofractionated Radiation Therapy Among Patients with Invasive Breast Cancer or Ductal Carcinoma In Situ: Who is Left Behind?

PURPOSE

We aimed to update the trend of hypofractionated whole-breast irradiation (HF-WBI) use over time in the US and examine factors associated with lack of HF-WBI adoption for patients with early-stage invasive breast cancer (IBC) or ductal carcinoma in situ (DCIS) undergoing a lumpectomy.

METHODS AND MATERIALS

Among patients who underwent a lumpectomy, we identified 928,034 patients with early-stage IBC and 330,964 patients with DCIS in the 2004 to 2020 National Cancer Database. We defined HF-WBI as 2.5-3.33 Gy/fraction to the breast and conventionally fractionated WBI as 1.8-2.0 Gy/fraction. We evaluated the trend of HF-WBI utilization using a generalized linear model with the log link and binomial distribution. Factors associated with HF-WBI utilization were assessed using multivariable logistic regression in patients diagnosed between 2018 and 2020.

RESULTS

Among patients with IBC, HF-WBI use has significantly increased from 0.7% in 2004 to 63.9% in 2020. Similarly, HF-WBI usage among patients with DCIS has also increased significantly from 0.4% in 2004 to 56.6% in 2020. Black patients with IBC were less likely than White patients to receive HF-WBI (adjusted odds ratio [AOR] 0.81; 95% CI, 0.77-0.85). Community cancer programs were less likely to administer HF-WBI to patients with IBC (AOR, 0.80; 95% CI, 0.77-0.84) and to those with DCIS (AOR, 0.87; 95% CI, 0.79-0.96) than academic/research programs. Younger age, positive nodes, larger tumor size, low volume programs, and facility location were also associated with lack of HF-WBI adoption in both patient cohorts.

CONCLUSIONS

HF-WBI utilization among postlumpectomy patients has significantly increased from 2004 to 2020 and can finally be considered standard of care in the US. We found substantial disparities in adoption within patient and facility subgroups. Reducing disparities in HF-WBI adoption has the potential to further alleviate health care costs while improving patients' quality of life.

Expenditures and Use of Hypofractionated Radiation Therapy Treating Breast Cancer Among Medicare Advantage Enrollees, 2009 to 2017

Purpose

Technology advances in cancer care have paralleled rapidly increasing expenditures in radiation therapy. The use and costs of shorter cancer radiation therapy offer potential utility in clinical practice. We evaluate use and expenditures of Medicare Advantage (MA) beneficiaries receiving hypofractionated whole breast irradiation (HF-WBI) compared with conventionally fractionated whole breast irradiation (CF-WBI) in the United States and examine the relationship of patient characteristics with HF-WBI use.

Methods and Materials

We performed a retrospective analysis of radiation therapy in MA beneficiaries using private employer-sponsored insurance claims for a pooled cross-sectional evaluation from 2009 to 2017. The study population included female MA beneficiaries with early-stage breast cancer treated with lumpectomy and whole breast irradiation.

Results

A total of 9957 women received HF-WBI, and 18,920 received CF-WBI. Older age, greater distance from home to treatment facility, and a higher proportion of college graduates in the community of residence were associated with increased HF-WBI use. Mean insurer-paid radiation therapy expenditures were significantly lower for HF-WBI versus CF-WBI (adjusted difference, $4113; 95% CI, $4030-$4,197). Mean patient out-of-pocket expenditure for HF-WBI was $426 less than that of CF-WBI. Across US states, geographic variation existed in the ratio of costs for HF-WBI relative to CF-WBI (range, 0.41-0.87).

Conclusions

HF-WBI use among MA beneficiaries with breast cancer has dramatically increased over time, surpassing CF-HBI as the dominant form of radiation therapy. HF-WBI clinical adoption has outpaced any continual cost decrease, despite wide variation across US states for this shorter radiation therapy treatment. As MA enrollment continues to expand, identifying the drivers of HF-WBI use and the sources of variation in costs of HF-WBI will help direct the quality of cancer care delivered to Medicare beneficiaries.

Radiation-induced dermatitis among breast cancer patients undergoing adjuvant radiotherapy in Ghana

The aim of the study was to investigate radiation-induced epidermal desquamation among breast cancer patients undergoing radiotherapy with 6MV linac and Co-60 teletherapy units. METHOD: Quantitative data was collected using self-administered closed ended questionnaires addressing the desquamation in relation to some patient-and treatment-related factors. The Radiation Therapy Oncology Group (RTOG) criteria for acute skin toxicity was used to grade the toxicity. Chi square and logistic regression analyses were respectively used to test statistical significance and evaluate the effects of the various factors on radiation induced epidermal desquamation RESULTS: Majority of the participants had high BMIs (overweight: 39.5 %; obese: 50 %). Patients with BMI ≥ 25 kg/m2 presented with wet desquamation (RTOG grade 2). A chi-square analysis showed a significant difference (p = 0.02) between BMI and severity of desquamation. There was no significant difference between type of treatment machine and cumulative incidence dose of desquamation (p= 0.251). The logistic regression analysis showed that patients who had undergone mastectomy (OR = 0.562) were less likely to develop wet desquamation (RTOG grade 2) on the Co-60 machine within the 20-30 Gy threshold (OR=0.981) compared to those on the linear accelerator. Patients with lower BMI (OR = 0.412,[ < 25 vs ≥30]; OR = 0.286, [25-29.9 vs ≥30]) were also less likely to develop wet desquamation compared to those with higher BMI. CONCLUSION: Radiation-induced epidermal desquamation is a common side effect of breast cancer patients undergoing radiotherapy. BMI has an effect on the severity of desquamation experienced during breast irradiation.

Are We Missing Acute Toxicities Associated With Hypofractionated Breast Irradiation? A Report From a Large Multicenter Cohort Study

PURPOSE

The efficacy and long-term safety of hypofractionated whole breast irradiation (HF-WBI) have been established through multiple randomized trials, yet data about acute toxicities remain more limited. Since 2013, our group has prospectively collected acute toxicity data from weekly treatment evaluations and additional assessment after completion. In 2016, we intentionally shifted the posttreatment assessment follow-up visit from 1 month to 2 weeks to evaluate for missed acute toxicity occurring in that immediate posttreatment window. Here, we report whether 2-week follow-up has resulted in increased detection of acute toxicities compared with 4-week follow-up.

METHODS AND MATERIALS

We prospectively compared acute toxicity for patients treated with HF-WBI between January 1, 2013, and August 31, 2015 (4 week follow-up cohort) to patients treated between January 1, 2016, and August 31, 2018 (2 week follow-up cohort). Analyses included a multivariable model that adjusted for other factors known to correlate with toxicity. We prospectively defined acute toxicity as maximum breast pain (moderate or severe rating) and/or occurrence of moist desquamation reported 7 days before the completion of radiation therapy (RT) until 42 days after completion.

RESULTS

A total of 2689 patients who received postlumpectomy radiation and boost were analyzed; 1862 patients in the 2-week follow-up cohort and 827 in the 4-week follow-up cohort. All acute toxicity measures assessed were statistically similar between follow-up cohorts when compared in an unadjusted fashion. Overall acute composite toxicity was 26.4% and 27.7% for patients in the 4-week follow-up and 2-week follow-up cohorts, respectively. Overall acute composite toxicity remained similar between follow-up cohorts in a multivariable, adjusted model and was significantly related to patient's age, body mass index, smoking status, and treatment technique (intensity-modulated RT vs 3-dimensional conformal radiation therapy) but not follow-up cohort.

CONCLUSIONS

An earlier posttreatment follow-up for HF-WBI patients did not reveal a significant increased incidence of acute toxicities at 2 weeks compared with 4 weeks. This study provides physicians and patients with additional data on the safety and tolerability of HF-WBI for early stage breast cancer.

Update on Management of Ductal Carcinoma in Situ

Ductal carcinoma in situ (DCIS) represents 18% to 25% of all diagnosed breast cancers, and is a noninvasive, nonobligate precursor lesion to invasive cancer. The diagnosis of DCIS represents a wide range of disease, including lesions with both low and high risk of progression to invasive cancer and recurrence. Over the past decade, research on the topic of DCIS has focused on the possibility of tailoring treatment for patients according to their risk for progression and recurrence, which is based on clinicopathologic, biomolecular and genetic factors. These efforts are ongoing, with recently completed and continuing clinical trials spanning the continuum of cancer care. We conducted a review to identify recent advances on the topic of diagnosis, risk stratification and management of DCIS. While novel imaging techniques have increased the rate of DCIS diagnosis, questions persist regarding the optimal management of lesions that would not be identified with conventional methods. Additionally, among trials investigating the potential for omission of surgery and use of active surveillance, 2 trials have completed accrual and 2 clinical trials are continuing to enroll patients. Identification of novel genetic patterns is expanding our potential for risk stratification and aiding our ability to de-escalate radiation and systemic therapies for DCIS. These advances provide hope for tailoring of DCIS treatment in the near future.

Radiation Therapy for Breast Cancer in Africa

Purpose

Although radiation therapy is an effective treatment for breast cancer, it has a low rate of use in African countries. A systematic review was undertaken to investigate studies that used radiation therapy as a treatment modality for patients with breast cancer in Africa, focusing on survival outcomes, adverse effects, radiation therapy techniques, fractionation schedules, and effectiveness of radiation therapy.

Methods and Materials

We conducted a comprehensive literature search for studies that treated breast cancer with radiation therapy, using different electronic databases (PubMed, Scopus, and EBSCOhost) up to February 2023. The output was exported to a reference management system for analyses.

Results

The literature search primarily identified 3804 records from Scopus (2427), PubMed (982), and EBSCOhost (395). Based on the inclusion and exclusion criteria, 19 articles were finally included in this systematic review. Most of the studies published were conducted in North Africa (63%), followed by West Africa (21%) and Southeast Africa (16%). Most centers employed external beam radiation therapy to deliver radiation therapy to patients with breast cancer with the standard fractionation size of 50 Gy in 25 fractions. The long-term outcomes with regards to adverse effect suggests that radiation therapy was fairly tolerated among patients with breast cancer.

Conclusions

The reports provide substantial evidence that there are limited number of published studies on the use of radiation therapy for breast cancer treatment in Africa, as well as lower overall survival rate compared with developed countries. To improve breast cancer survivorship, it is necessary for government and other health care planners to provide more radiation therapy resources and implement training programs for personnels.

Geographic and Physician-Level Variation in the Use of Hypofractionated Radiation Therapy for Breast Cancer in the U.S.: A Cross-Classified Multilevel Analysis

Purpose

We aimed to assess geographic and physician-level variation for hypofractionated whole-breast irradiation (HF-WBI) use for early-stage breast cancer patients in the United States. We further evaluated the association between HF-WBI use and demographic factors after accounting for these variations.

Methods and Materials

We performed a retrospective study of early-stage breast cancer patients using private employer-sponsored insurance claims from 2008 to 2017. Patients were clustered according to geographic level and by radiation oncologist. Bayesian cross-classified multilevel logistic models were used to examine the geographic heterogeneity and variation of radiation oncologists simultaneously. Intracluster correlation coefficient (ICC) and median odds ratios (MOR) were calculated to quantify the variation at different levels. We also used the cross-classified model to identify patient demographic factors associated with receiving HF-WBI.

Results

The study included 79,747 women (74.0%) who received conventionally fractionated whole-breast irradiation (CF-WBI) and 27,999 women (26.0%) who underwent HF-WBI. HF-WBI adoption increased significantly across time (2008-2017). The variation in HF-WBI utilization was attributed mostly to physician-level variability (MOR = 2.59). The variability of HF-WBI utilization across core-based statistical areas (CBSAs) (MOR = 1.55) was found to be the strongest among all geographic classifications. After accounting for variability in both CBSAs and radiation oncologists, age, receiving chemotherapy, and several community-level factors, including distance from home to facility, community education level, and racial composition, were found to be associated with HF-WBI utilization.

Conclusion

This study demonstrated geographic and physician-level heterogeneity in the use of HF-WBI among early-stage breast cancer patients. HF-WBI utilization was also found to be associated with patient and community-level characteristics. Given observed physician-level variability, intervention through continuing medical education could help doctors to better understand the advantages of HF-WBI and promote the adoption of HF-WBI in the U.S. Influence of physician-level characteristics on HF-WBI utilization merits further study.

The Japanese breast cancer society clinical practice guidelines for radiation treatment of breast cancer, 2022 edition

The Breast Cancer Clinical Practice Guidelines, organized by the Japanese Breast Cancer Society (JBCS), were published in 2022. We present the English version of the Radiation Therapy (RT) section of the guidelines. The JBCS formed a task force to update the 2018 version of the JBCS Clinical Practice Guidelines. The Background Questions (BQs) contain the standard treatments for breast cancer in clinical practice, whereas the Clinical Questions (CQs) address daily clinical questions that remain controversial. Future Research Questions (FRQs) explore the subjects that are considered important issues, despite there being insufficient data for inclusion as CQs. The task force selected the 12 BQs, 8 CQs, and 6 FRQs for the RT section. For each CQ, systematic literature reviews and meta-analyses were conducted according to the Minds Manual for Guideline Development 2020, version 3.0. The recommendations, strength of recommendation, and strength of evidence for each CQ were determined based on systematic reviews and meta-analyses, and finalized by voting at the recommendation decision meeting.

Women's Preferences for Hypofractionated Radiation Therapy for Treatment of Early-Stage Breast Cancer: A Discrete Choice Experiment

PURPOSE

The primary treatment recommended for early-stage breast cancer is breast conserving surgery followed by external beam radiation therapy of the whole breast. Previously, radiation therapy for early-stage breast cancer was given using more fractions over longer durations. Guidelines support treatments with fewer fractions over a shorter time (hypofractionated radiation therapy). This study aimed to understand women's preferences for different features of treatments for early-stage breast cancer.

METHODS AND MATERIALS

A discrete choice experiment with 12 choice tasks was conducted, describing the treatments by extent of surgery, duration of radiation treatment, need to relocate for treatment, local side effects, changes in breast appearance, costs, and difficulty with daily activities during and after treatment. Participants were women with breast cancer and from the general population. Mixed logit analyses were conducted and trade-offs between attributes estimated.

RESULTS

Four hundred twenty respondents completed the discrete choice experiment. The relative importance of attributes varied by respondent characteristics; the most influential attribute for younger women was type of surgery (breast conserving surgery). Type of surgery did not influence older women's preferences. Shorter treatment duration, avoiding relocation, fewer local side effects, and less difficulty with daily activities all positively influenced treatment preference. Younger women were willing to accept 32 to 40 days of radiation treatment before a treatment that included mastectomy was potentially acceptable.

CONCLUSIONS

Attributes of treatment such as duration, need for relocation, side effects, and effects on normal daily activities during and after treatment significantly influenced women's preference for treatment, including surgery. Our findings have the potential for real impact for patients and services including supporting one-on-one clinical discussions, supporting program and patient resource development, and informing service funding, organization, and delivery.

A comparative study of boost dose delivery techniques in breast cancer radiotherapy optimising efficacy and minimising toxicity

The present study aims to compare three techniques for delivering a boost absorbed dose: conventional reduced tangential (3D), volumetric modulated arc therapy (VMAT) and fields forward-planned technique boost (3DF). The study included 15 postoperative breast cancer patients who received a boost absorbed dose following breast-conserving surgery. The conformity index and homogeneity index were used to evaluate treatment outcomes, along with the average absorbed dose received by organs at risk (OAR). All the calculated dosimetric plans are carried out using Monaco Treatment Planning System (TPS). VMAT offers superior conformity, dose homogeneity and target coverage, it is associated with higher absorbed doses to OAR such as the heart and lung. In contrast, the 3D and 3DF techniques exhibit advantages in reducing absorbed doses to critical structures, potentially minimising the risk of cardiac and pulmonary complications. Each technique has its advantages and disadvantages. The choice of technique should be individualised, taking into account patient-specific factors and treatment goals and involves a multidisciplinary approach.

Rates of adherence to cancer treatment guidelines in Australia and the factors associated with adherence: A systematic review

Adherence to cancer treatment clinical practice guidelines (CPGs) varies enormously across Australia, despite being associated with improved patient outcomes. This systematic review aims to characterize adherence rates to active-cancer treatment CPGs in Australia and related factors to inform future implementation strategies. Five databases were systematically searched, abstracts were screened for eligibility, a full-text review and critical appraisal of eligible studies performed, and data extracted. A narrative synthesis of factors associated with adherence was conducted, and the median adherence rates within cancer streams calculated. A total of 21,031 abstracts were identified. After duplicates were removed, abstracts screened, and full texts reviewed, 20 studies focused on adherence to active-cancer treatment CPGs were included. Overall adherence rates ranged from 29% to 100%. Receipt of guideline recommended treatments was higher for patients who were younger (diffuse large B-cell lymphoma [DLBCL], colorectal, lung, and breast cancer); female (breast and lung cancer), and male (DLBCL and colorectal cancer); never smokers (DLBCL and lung cancer); non-Indigenous Australians (cervical and lung cancer); with less advanced stage disease (colorectal, lung, and cervical cancer), without comorbidities (DLBCL, colorectal, and lung cancer); with good-excellent Eastern Cooperative Oncology Group performance status (lung cancer); living in moderately accessible places (colon cancer); and; treated in metropolitan facilities (DLBLC, breast and colon cancer). This review characterized active-cancer treatment CPG adherence rates and associated factors in Australia. Future targeted CPG implementation strategies should account for these factors, to redress unwarranted variation particularly in vulnerable populations, and improve patient outcomes (Prospero number: CRD42020222962).

One versus three weeks hypofractionated whole breast radiotherapy for early breast cancer treatment: the FAST-Forward phase III RCT

Background

FAST-Forward aimed to identify a 5-fraction schedule of adjuvant radiotherapy delivered in 1 week that was non-inferior in terms of local cancer control and as safe as the standard 15-fraction regimen after primary surgery for early breast cancer. Published acute toxicity and 5-year results are presented here with other aspects of the trial.

Design

Multicentre phase III non-inferiority trial. Patients with invasive carcinoma of the breast (pT1-3pN0-1M0) after breast conservation surgery or mastectomy randomised (1 : 1 : 1) to 40 Gy in 15 fractions (3 weeks), 27 Gy or 26 Gy in 5 fractions (1 week) whole breast/chest wall (Main Trial). Primary endpoint was ipsilateral breast tumour relapse; assuming 2% 5-year incidence for 40 Gy, non-inferiority pre-defined as < 1.6% excess for 5-fraction schedules (critical hazard ratio = 1.81). Normal tissue effects were assessed independently by clinicians, patients and photographs.

Sub-studies

Two acute skin toxicity sub-studies were undertaken to confirm safety of the test schedules. Primary endpoint was proportion of patients with grade ≥ 3 acute breast skin toxicity at any time from the start of radiotherapy to 4 weeks after completion. Nodal Sub-Study patients had breast/chest wall plus axillary radiotherapy testing the same three schedules, reduced to the 40 and 26 Gy groups on amendment, with the primary endpoint of 5-year patient-reported arm/hand swelling.

Limitations

A sequential hypofractionated or simultaneous integrated boost has not been studied.

Participants

Ninety-seven UK centres recruited 4096 patients (1361:40 Gy, 1367:27 Gy, 1368:26 Gy) into the Main Trial from November 2011 to June 2014. The Nodal Sub-Study recruited an additional 469 patients from 50 UK centres. One hundred and ninety and 162 Main Trial patients were included in the acute toxicity sub-studies.

Results

Acute toxicity sub-studies evaluable patients: (1) acute grade 3 Radiation Therapy Oncology Group toxicity reported in 40 Gy/15 fractions 6/44 (13.6%); 27 Gy/5 fractions 5/51 (9.8%); 26 Gy/5 fractions 3/52 (5.8%). (2) Grade 3 common toxicity criteria for adverse effects toxicity reported for one patient. At 71-month median follow-up in the Main Trial, 79 ipsilateral breast tumour relapse events (40 Gy: 31, 27 Gy: 27, 26 Gy: 21); hazard ratios (95% confidence interval) versus 40 Gy were 27 Gy: 0.86 (0.51 to 1.44), 26 Gy: 0.67 (0.38 to 1.16). With 2.1% (1.4 to 3.1) 5-year incidence ipsilateral breast tumour relapse after 40 Gy, estimated absolute differences versus 40 Gy (non-inferiority test) were -0.3% (-1.0-0.9) for 27 Gy (p = 0.0022) and -0.7% (-1.3-0.3) for 26 Gy (p = 0.00019). Five-year prevalence of any clinician-assessed moderate/marked breast normal tissue effects was 40 Gy: 98/986 (9.9%), 27 Gy: 155/1005 (15.4%), 26 Gy: 121/1020 (11.9%). Across all clinician assessments from 1 to 5 years, odds ratios versus 40 Gy were 1.55 (1.32 to 1.83; p < 0.0001) for 27 Gy and 1.12 (0.94-1.34; p = 0.20) for 26 Gy. Patient and photographic assessments showed higher normal tissue effects risk for 27 Gy versus 40 Gy but not for 26 Gy. Nodal Sub-Study reported no arm/hand swelling in 80% and 77% in 40 Gy and 26 Gy at baseline, and 73% and 76% at 24 months. The prevalence of moderate/marked arm/hand swelling at 24 months was 10% versus 7% for 40 Gy compared with 26 Gy.

Interpretation

Five-year local tumour incidence and normal tissue effects prevalence show 26 Gy in 5 fractions in 1 week is a safe and effective alternative to 40 Gy in 15 fractions for patients prescribed adjuvant local radiotherapy after primary surgery for early-stage breast cancer.

Future work

Ten-year Main Trial follow-up is essential. Inclusion in hypofractionation meta-analysis ongoing. A future hypofractionated boost trial is strongly supported.

Trial registration

FAST-Forward was sponsored by The Institute of Cancer Research and was registered as ISRCTN19906132.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 09/01/47) and is published in full in Health Technology Assessment; Vol. 27, No. 25. See the NIHR Funding and Awards website for further award information.

Limited applicability and implementation of the international oncology treatments guidelines in low- and middle-income countries, an example from the Mediterranean area borders

The quality of cancer care in the modern era is based on a precise diagnosis and personalized therapy according to patients and their disease based on validated guidelines with a high level of evidence. During cancer patients' management, the objective is first to make an accurate diagnosis and then offer the best treatment, validated beforehand in a multidisciplinary board meeting, with the best benefit/risk ratio. In the context of many low- and middle-income countries, the limited available means do not allow an adequate offer, resulting in non-optimal patients' care. In addition, in many low- and middle-income countries, priority can be given to other types of disease than cancer, which may considerably reduce allocation of specific resources to cancer care. Thus, the limited availability of systemic therapy, radiotherapy machines, brachytherapy and technological development may come up against another difficulty, that of geographical distribution of the means in the countries or a lack of expertise due to insufficient training programs. For all these reasons, the implementation of the guidelines established in Western countries could be impossible for many low- and middle-income countries which, moreover, have to face a completely different epidemiology of cancers compared to developed countries. In this work, we will discuss through a few examples of common cancers on both borders of the Mediterranean area, the applicability of the guidelines and the limits of their implementation for optimal cancer care.

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.

Incorporating financial toxicity considerations into clinical trial design to facilitate patient-centered decision-making in oncology

PLAIN LANGUAGE SUMMARY

Financial toxicity is increasingly being recognized as an important and devastating consequence of cancer treatment that receives little attention when clinical trials are being designed. There is a significant need to obtain this important information in an era of increasingly expensive anticancer treatments. Patients who are informed of all implications of therapy-efficacy, side effects, cost, and broader financial impact-are able to select the best cancer treatment for themselves.

What Is Known about Breast Cancer in Young Women?

Breast cancer (BC) is the second leading cause of cancer-related death in women under the age of 40 years worldwide. In addition, the incidence of breast cancer in young women (BCYW) has been rising. Young women are not the focus of screening programs and BC in younger women tends to be diagnosed in more advanced stages. Such patients have worse clinical outcomes and treatment complications compared to older patients. BCYW has been associated with distinct tumour biology that confers a worse prognosis, including poor tumour differentiation, increased Ki-67 expression, and more hormone-receptor negative tumours compared to women >50 years of age. Pathogenic variants in cancer predisposition genes such as BRCA1/2 are more common in early-onset BC compared to late-onset BC. Despite all these differences, BCYW remains poorly understood with a gap in research regarding the risk factors, diagnosis, prognosis, and treatment. Age-specific clinical characteristics or outcomes data for young women are lacking, and most of the standard treatments used in this subpopulation currently are derived from older patients. More age-specific clinical data and treatment options are required. In this review, we discuss the epidemiology, clinicopathologic characteristics, outcomes, treatments, and special considerations of breast cancer in young women. We also underline future directions and highlight areas that require more attention in future studies.

Dose and organ displacement comparisons with breast conservative radiotherapy using abdominal and thoracic deep-inspiration breath-holds: A comparative dosimetric study

Deep-inspiration breath-hold (DIBH) reduces the radiation dose to the heart and lungs during breast radiotherapy in cancer. However, there is not enough discussion about suitable breathing methods for DIBH. Therefore, we investigated the radiation doses and organ and body surface displacement in abdominal DIBH (A-DIBH) and thoracic DIBH (T-DIBH). Free-breathing, A-DIBH, and T-DIBH computed tomography images of 100 patients were used. After contouring the targets, heart, and lungs, radiotherapy plans were created. We investigated the heart and lung doses, the associations between the heart and left lung displacements, and the thorax and abdominal surface displacements. No significant differences were observed in the target dose indices. However, the heart and lung doses were significantly lower in A-DIBH than in T-DIBH for all the indices; the mean heart and lung doses were 1.69 and 3.48 Gy, and 1.91 and 3.55 Gy in A-DIBH and T-DIBH, respectively. The inferior displacement of the heart and the left lung was more significant in A-DIBH. Therefore, inferior expansion of the heart and lungs may be responsible for the respective dose reductions. The abdominal surface displaced more than the thoracic surface in both A-DIBH and T-DIBH, and thoracic surface displacement was greater in T-DIBH than in A-DIBH. Moreover, A-DIBH can be identified because abdominal surface displacement was greater in A-DIBH than in T-DIBH. In conclusion, A-DIBH and T-DIBH could be distinguished by comparing the abdominal and thoracic surfaces of A-DIBH and T-DIBH, thereby ensuring the implementation of A-DIBH and reducing the heart and lung doses.

Treatment-related thoracic soft tissue sarcomas in US breast cancer survivors: a retrospective cohort study

BACKGROUND

Soft tissue sarcoma is a rare but serious side-effect of radiotherapy to treat breast cancer, and rates are increasing in the USA. We evaluated potential co-factors in two complimentary cohorts of US breast cancer survivors.

METHODS

In this retrospective cohort study, we sourced data from the Kaiser Permanente (KP) cohort and the Surveillance, Epidemiology, and End Results (SEER) 13 registries cohort, both in the USA. The KP cohort included 15 940 women diagnosed with breast cancer from Jan 1, 1990, to Dec 31, 2016, in KP Colorado, KP Northwest (which serves Oregon and Southwest Washington state), or KP Washington, with detailed treatment data and comorbidities (including hypertension and diabetes at or before breast cancer diagnosis) from electronic medical records. The SEER cohort included 457 300 women diagnosed with breast cancer from Jan 1, 1992, to Dec 31, 2016, within the 13 SEER registries across the USA, with initial treatment data (yes vs no or unknown). Eligibility criteria in both cohorts were female breast cancer survivors (stage I-III) aged 20-84 years at diagnosis who had breast cancer surgery, and had survived at least 1 year after breast cancer diagnosis. The outcome of interest was any second thoracic soft tissue sarcoma (angiosarcomas and other subtypes) that developed at least 1 year after breast cancer diagnosis. Risk factors for thoracic soft tissue sarcoma were assessed using multivariable Poisson regression models.

FINDINGS

In the KP cohort, median follow-up was 9·3 years (IQR 5·7-13·9) and 19 (0·1%) of 15 940 eligible, evaluable women developed a thoracic soft tissue sarcoma (11 angiosarcomas, eight other subtypes). Most (94·7%; 18 of 19) thoracic soft tissue sarcomas occurred in women treated with radiotherapy; thus, radiotherapy was associated with a significantly increased risk of developing a thoracic soft tissue sarcoma (relative risk [RR] 8·1 [95% CI 1·1-60·4]; p=0·0052), but there was no association with prescribed dose, fractionation, or boost. The RR of angiosarcoma after anthracyclines was 3·6 (95% CI 1·0-13·3; p=0·058). Alkylating agents were associated with an increased risk of developing other sarcomas (RR 7·7 [95% CI 1·2-150·8]; p=0·026). History of hypertension (RR 4·8 [95% CI 1·3-17·6]; p=0·017) and diabetes (5·3 [1·4-20·8]; p=0·036) were each associated with around a five-times increased risk of angiosarcoma. In the SEER cohort, 430 (0·1%) of 457 300 patients had subsequent thoracic soft tissue sarcomas (268 angiosarcomas and 162 other subtypes) after a median follow-up of 8·3 years (IQR 4·3-13·9). Most (77·9%; 335 of 430) cases occurred after radiotherapy; thus, radiotherapy was associated with a significantly increased risk of developing a thoracic soft tissue sarcoma (RR 3·0 [95% CI 2·4-3·8]; p<0·0001) and, for angiosarcomas, the RR for breast-conserving surgery plus radiotherapy versus mastectomy plus radiotherapy was 1·9 (1·1-3·3; p=0·012). By 10 years after radiotherapy, the cumulative incidence of thoracic soft tissue sarcoma was 0·21% (95% CI 0·12-0·34) in the KP cohort and 0·15% (95% CI 0·13-0·17) in SEER.

INTERPRETATION

Radiotherapy was the strongest risk factor for thoracic soft tissue sarcoma in both cohorts. This finding, along with the novel findings for diabetes and hypertension as potential risk factors for angiosarcomas, warrant further investigation as potential targets for prevention strategies and increased surveillance.

FUNDING

US National Cancer Institute and National Institutes of Health.

A comparison of timely completion of hypofractionated and traditional adjuvant radiation therapy in early-stage breast cancer: Evidence of impact on reducing racial and socioeconomic disparities

BACKGROUND

Timely completion of adjuvant radiation after breast conservation therapy is associated with decreased mortality and increased disease-free survival. Few data exist comparing timely completion between hypofractionated radiation and traditional radiation at a national level or across racial and socioeconomic cohorts.

METHODS

A retrospective review of the National Cancer Database (2012-2016) on patients undergoing breast conservation therapy for early-stage breast cancer, specifically T1 or T2, N0, M0 patients, was performed. Multivariable logistic regression models were used to compare timely completion of hypofractionated radiation (within 5 weeks of initiation) and traditional radiation (within 7 weeks) across patient, tumor, and facility characteristics.

RESULTS

In total, 210,816 patients met criteria, with 59.4% receiving traditional radiation (n = 125,140) and 40.6% receiving hypofractionated radiation (n = 85,676). Overall, 82.8% of patients achieved timely completion of radiation. Among hypofractionated radiation patients, 94.5% of patients achieved timely completion, whereas only 74.8% of traditional radiation patients achieved timely completion (P < .0001). Regarding race/ethnicity, all groups benefited substantially in timely completion of hypofractionated radiation over traditional radiation. However, both treatment cohorts demonstrated that Black (odds ratio (hypofractionated radiation) = 0.842, odds ratio (traditional radiation) = 0.821) and Hispanic (odds ratio (hypofractionated radiation) = 0.917, odds ratio (traditional radiation) = 0.907) patients had lower odds of timely completion compared to White patients (P < .0001). Lower high school graduation rate, median income for patients' ZIP code, and Medicaid were also associated with lower odds of timely completion for both hypofractionated radiation and traditional radiation (both P < .0001).

CONCLUSION

Timely completion of radiation therapy in breast conservation therapy is greater for patients receiving hypofractionated radiation than traditional radiation across racial and socioeconomic cohorts. Disparities in timely completion were substantially reduced with hypofractionated radiation utilization. However, there are treatment disparities across racial and socioeconomic cohorts that persist in both treatment groups.

Clinical Outcomes of Hypofractionated Whole Breast Irradiation in Early-Stage, Biologically High-Risk Breast Cancer

PURPOSE

Adoption of hypofractionated whole breast irradiation (WBI) for patients with early-stage, biologically high-risk breast cancer remains relatively low. We compared clinical outcomes of conventionally fractionated versus moderately hypofractionated WBI in this patient population.

METHODS

We queried a prospectively maintained database for patients with early-stage (T1-2, N0, M0) breast cancer who received whole breast irradiation with either conventional fractionation (CWBI) or moderate hypofractionation (HWBI) at a single institution. We included only patients with biologically high-risk tumors (defined as either ER/PR/HER-2 negative, HER-2 amplified, and/or patients with a high-risk multi-gene assay) who received systemic chemotherapy. Inverse probability of treatment weighting (IPTW) was used to compare treatment cohorts and to estimate 5-year time to event endpoints. Hazard ratios (HR) and 95% CI were determined based on Cox Proportional Hazards Model.

RESULTS

We identified 300 patients, of whom 171 received CWBI and 129 received HWBI. There was a statistically significant difference in median age at diagnosis, 59 years for CWBI vs 63 years for HWBI (p = 0.004), and in median follow-up time, 97 months for CWBI vs 55 months for HWBI (p < 0.001). After accounting for differences in patient and tumor characteristics with IPTW, we found similar 5-year freedom from local recurrence (HR 0.76, 95% CI 0.14-4.1), freedom from regional recurrence (HR 3.3, 95% CI 0.15-69), freedom from distant metastasis (HR 3.9, 95% CI 0.86-17), and disease-free survival (HR 0.84, 95% CI 0.3-2.4), between those treated with CWBI and those treated with HWBI. Results were similar among each of the three high-risk subtypes.

CONCLUSION

Our data support the use of moderately hypofractionated whole breast irradiation in patients with early-stage, biologically high-risk breast cancer.

Rapamycin Ameliorates Radiation-Induced Testis Damage in Mice

Male infertility is an important problem in human and animal reproduction. The testis is the core of male reproduction, which is very sensitive to radiation. The decline of male reproductive ability is a common trend in the world. Radiation is a physical factor leading to abnormal male reproductive function. To investigate the potential mechanisms of testicular damage induced by radiation and explore effective strategies to alleviate radiation-induced testis injury, C57BL/6 mice were irradiated with 8.0 Gy of X-ray irradiation. Testis and epididymis were collected at days 1, 3, and 7 after radiation exposure to analyze spermatogonia and sperm function. The results showed that radiation significantly destroyed testicular structure and reduced the numbers of spermatogonia. These were associated with mTORC1 signaling activation, decreased cellular proliferation and increased apoptotic cells in the irradiated testis. Rapamycin significantly blocked mTORC1 signaling pathway in the irradiated testis. Inhibition of mTORC1 signaling pathway by rapamycin treatment after radiation could significantly improve cell proliferation in testis and alleviate radiation-induced testicular injury after radiation exposure. Rapamycin treatment benefited cell survival in testis to maintain spermatogenesis cycle at 35 days after irradiation. These findings imply that rapamycin treatment can accelerate testis recovery under radiation condition through inhibiting mTORC1 signaling pathway.

Favorable safety profile of moderate hypofractionated over normofractionated radiotherapy in breast cancer patients: a multicentric prospective real-life data farming analysis

Background

Moderately hypofractionated whole-breast radiotherapy (HFRT) has proven to be as safe and efficient as normofractionated radiotherapy (NFRT) in randomized trials resulting in major changes in clinical practice. Toxicity rates observed in selected clinical trial patients may differ from those observed in unselected patients with possible comorbidities and frailty in real-life. This study aimed to examine the influence of HFRT versus NFRT on acute toxicity and identify risks factors of dermatitis in real-life patients.

Materials and methods

Prospective data from breast cancer patients, treated with locoregional radiotherapy were collected between November 2015 and February 2020 in 3 comprehensive cancer centers. Through a systematic data-farming strategy, acute toxicity evaluation forms (CTCAEv4.0) were prospectively completed and extracted electronically. The results from each center were then anonymously merged into a single database for analysis. A Chi-2 test was used to compare HFRT and NFRT. Furthermore, risk factors of dermatitis were identified in a sub-study (622 patients) by multivariate logistic regression analysis.

Results

In total, 3518 T0-4 N0-3 mostly M0 (85.8%) breast cancer patients with a median age of 60.7 (24–96 years old) were analyzed. Acute grade 2–3 dermatitis, grade 1–3 breast oedema, and grade 1–2 hyperpigmentation were less frequent with HFRT versus NFRT: respectively 8.9% versus 35.1% (Chi-2 = 373.7; p < 0.001), 29.0% versus 37.0% (Chi-2 = 23.1; p < 0.001) and 27.0% versus 55.8% (Chi-2 = 279.2; p < 0.001). Fewer patients experienced pain with HFRT versus NFRT: 33.4% versus 53.7% respectively (Chi-2 = 137.1; p < 0.001). Factors such as high BMI (OR = 2.30 [95% CI, 1.28–4.26], p < 0.01), large breast size (OR = 1.88 [95% CI, 1.07–3.28], p < 0.01) and lumpectomy over mastectomy (OR = 0.52 [95% CI, 0.27–0.97], p < 0.05) were associated with greater risk factors of grade 2–3 dermatitis in multivariate analysis regardless of NFRT or HFRT.

Conclusion

The results of this study suggests that breast HFRT may be a better option even for patients with a high BMI or large breast size. Acute toxicity was low to mild, and lower with HFRT compared to NFRT. Results from real-life data were robust, and support the use of HFRT beyond randomized study populations. Long-term real-life data awaits further investigation.

Single fraction ablative preoperative radiation treatment for early-stage breast cancer: the CRYSTAL study – a phase I/II clinical trial protocol

Background

Breast-conserving surgery (BCS) and whole breast radiation therapy (WBRT) are the standard of care for early-stage breast cancer (BC). Based on the observation that most local recurrences occurred near the tumor bed, accelerated partial breast irradiation (APBI), consisting of a higher dose per fraction to the tumor bed over a reduced treatment time, has been gaining ground as an attractive alternative in selected patients with low-risk BC. Although more widely delivered in postoperative setting, preoperative APBI has also been investigated in a limited, though increasing, and number of studies. The aim of this study is to test the feasibility, safety and efficacy of preoperative radiotherapy (RT) in a single fraction for selected BC patients.

Methods

This is a phase I/II, single-arm and open-label single-center clinical trial using CyberKnife. The clinical investigation is supported by a preplanning section which addresses technical and dosimetric issues. The primary endpoint for the phase I study, covering the 1st and 2nd year of the research project, is the identification of the maximum tolerated dose (MTD) which meets a specific target toxicity level (no grade 3–4 toxicity). The primary endpoint for the phase II study (3rd to 5th year) is the evaluation of treatment efficacy measured in terms of pathological complete response rate.

Discussion

The study will investigate the response of BC to the preoperative APBI from different perspectives. While preoperative APBI represents a form of anticipated boost, followed by WBRT, different are the implications for the scientific community. The study may help to identify good responders for whom surgery could be omitted. It is especially appealing for patients unfit for surgery due to advanced age or severe co-morbidities, in addition to or instead of systemic therapies, to ensure long-term local control. Moreover, patients with oligometastatic disease synchronous with primary BC may benefit from APBI on the intact tumor in terms of tumor progression free survival. The study of response to RT can provide useful information about BC radiobiology, immunologic reactions, genomic expression, and radiomics features, to be tested on a larger scale.

Trial registration

The study was prospectively registered at clinicaltrials.gov (NCT04679454).

Implicaciones de la pandemia en la radioterapia para el cáncer de mama. Radioterapia hipofraccionada

La pandemia por el nuevo coronavirus (SARS-CoV-2) ha puesto a prueba los sistemas de salud de todo el mundo, de una forma tan apremiante que no se veía hace muchos años. Las implicaciones en la atención en salud no afectan únicamente a los pacientes con la COVID-19, sino que son transversales a todas las enfermedades. Específicamente en cáncer de mama, los esquemas de radioterapia hipofraccionada constituyen una alternativa válida y segura que ayuda a disminuir la exposición de las pacientes al nuevo virus, la congestión de las instituciones de salud y los costos propios de los tratamientos oncológicos especializados. En este artículo, se realizó una revisión de la literatura más relevante sobre los regímenes acortados de radioterapia en cáncer de mama: hipofraccionamiento e hipofraccionamiento extremo, y sobre su equivalencia con el fraccionamiento estándar. Al final, se destacan las recomendaciones de diferentes sociedades científicas y expertos internacionales, para considerar esquemas de radioterapia hipofraccionados, a propósito de la contingencia de salud mundial.

Disease Control After Hypofractionation Versus Conventional Fractionation for Triple Negative Breast Cancer: Comparative Effectiveness in a Large Observational Cohort

PURPOSE

Questions remain about whether moderately hypofractionated whole-breast irradiation is appropriate for patients with triple-negative breast cancer.

METHODS AND MATERIALS

Using the prospective database of a multicenter, collaborative quality improvement consortium, we identified patients with node-negative, triple-negative breast cancer who received whole-breast irradiation with either moderate hypofractionation or conventional fractionation. Using inverse probability of treatment weighting (IPTW), we compared outcomes using the Kaplan-Meier product-limit estimation method with Cox regression models estimating the hazard ratio for time-to-event endpoints between groups.

RESULTS

The sample included 538 patients treated at 18 centers in 1 state in the United States, of whom 307 received conventionally fractionated whole-breast irradiation and 231 received moderately hypofractionated whole-breast irradiation. The median follow-up time was 5.0 years (95% confidence interval [CI], 4.77-5.15 years). The 5-year IPTW estimates for freedom from local recurrence were 93.6% (95% CI, 87.8%-96.7%) in the moderate hypofractionation group and 94.4% (95% CI, 90.3%-96.8%) in the conventional fractionation group. The hazard ratio was 1.05 (95% CI, 0.51-2.17; P = .89). The 5-year IPTW estimates for recurrence-free survival were 87.8% (95% CI, 81.0%-92.4%) in the moderate hypofractionation group and 88.4% (95% CI 83.2%-92.1%) in the conventional fractionation group. The hazard ratio was 1.02 (95% CI, 0.62-1.67; P = .95). The 5-year IPTW estimates for overall survival were 96.6% (95% CI, 92.0%-98.5%) in the moderate hypofractionation group and 93.4% (95% CI, 88.7%-96.1%) in the conventional fractionation group. The hazard ratio was 0.65 (95% CI, 0.30-1.42; P = .28).

CONCLUSIONS

Analysis of outcomes in this large observational cohort of patients with triple-negative, node-negative breast cancer treated with whole-breast irradiation revealed no differences by dose fractionation. This adds evidence to support the use of moderate hypofractionation in patients with triple-negative disease.

Unwarranted variation in radiation therapy fractionation

The adoption of hypofractionation across multiple tumour sites has been slow despite robust evidence. There is considerable unwarranted variation in practice, both within and between jurisdictions. This has been attributed to inconsistencies in guidelines, physician preference, lack of technology and differing financial incentives. Unwarranted variation in the use of hypofractionation has a tremendous effect on cost to both patients and the healthcare system. This places an unnecessary burden on patients and poorly utilises scarce healthcare resources. A collaborative effort from clinicians, patients, healthcare providers and policymakers is needed to reduce unwarranted variation in practice. This will improve quality of care both for patients and at broader healthcare system level.

Hypofractionated Radiation Therapy for Breast Cancer: Financial Risk and Expenditures in the United States, 2008 to 2017

PURPOSE

Rising cancer care expenditures and technological advancement of shorter radiation therapy regimens have drawn significant attention to the use of hypofractionated radiation therapy in clinical care. We examine the costs of hypofractionated whole breast irradiation (HF-WBI) compared with conventional whole breast irradiation (CF-WBI) in the United States and investigate the influences of patient characteristics and commercial insurance on HF-WBI use.

METHODS AND MATERIALS

In a retrospective study using private employer-sponsored insurance claims, a pooled cross-sectional evaluation of radiation therapy in patients with commercial insurance was performed from 2008 to 2017. The study population included female patients with early-stage breast cancer treated with lumpectomy and whole breast irradiation.

RESULTS

A total of 15,869 women received HF-WBI, and 59,328 received CF-WBI. HF-WBI use increased from 2008 to 2017. Community-level factors such as a higher proportion of college graduates and greater mixed racial composition were associated with increased HF-WBI use. Mean insurer-paid radiation therapy expenditures were significantly lower for HF-WBI versus CF-WBI (adjusted difference, $6375; 95% confidence interval, $6147-$6603). Mean patient out-of-pocket expenditure for HF-WBI was $139 less than that for CF-WBI. Geographic variation existed across the United States in HF-WBI use (range, 9.6%-36.2%), with no consistent relationship between HF-WBI use and corresponding average cost differences between HF-WBI and CF-WBI.

CONCLUSIONS

If trends continue, HF-WBI will soon become the dominant form of radiation treatment in the United States. Although HF-WBI represents significant savings to the health care system and individual patients, no evidence indicated that a financial disincentive had slowed adoption of HF-WBI. Therefore, multilevel approaches, including individuals, the community, and health policy, should be used to promote cost-effective cancer care. Innovations to policies on cost-effective radiation therapy treatment might consider non-financial incentives to promote HF-WBI use.

The impact of chemotherapy on toxicity and cosmetic outcome in patients receiving whole breast irradiation: an analysis within a state-wide quality consortium

PURPOSE

We investigated whether the use of chemotherapy prior to whole breast irradiation (WBI) using either conventional fractionation (CWBI) or hypofractionation (HWBI) is associated with increased toxicity or worse cosmetic outcome compared to WBI alone.

METHODS AND MATERIALS

We identified 6,754 patients who received WBI alone (without a third field covering the superior axillary and supraclavicular nodal regions) with data prospectively collected in a state-wide consortium. We reported rates of four toxicity outcomes: physician-reported acute moist desquamation, patient-reported acute moderate/severe breast pain, a composite acute toxicity measure (including moist desquamation and either patient-reported or physician-reported moderate/significant breast pain), and physician-reported impaired cosmetic outcome at one year following WBI. Successive multivariable models were constructed to estimate the impact of chemotherapy on these outcomes.

RESULTS

Rates of moist desquamation, patient-reported pain, composite acute toxicity, and impaired cosmetic outcome were 23%, 34%, 42%, and 10% for 2,859 patients receiving CWBI and 13%, 28%, 31%, and 11% for 3,895 patients receiving HWBI. Receipt of chemotherapy prior to CWBI was not associated with higher rates of patient-reported pain, composite acute toxicity, or impaired cosmetic outcome compared to CWBI without chemotherapy but was associated with more moist desquamation (OR=1.32 [1.07-1.63], p=0.01). Receipt of chemotherapy prior to HWBI was not associated with higher rates of any of the four toxicity outcomes compared to HWBI alone.

CONCLUSIONS

In this cohort, use of chemotherapy prior to WBI was generally well tolerated. CWBI with chemotherapy, but not to HWBI with chemotherapy, was associated with higher rates of moist desquamation. Rates of acute breast pain and impaired cosmetic outcome at one year were comparable in patients receiving chemotherapy prior to either CWBI or HWBI. These data support the use of HWBI following chemotherapy.

Ultra-hypofractionated whole breast adjuvant radiotherapy in the real-world setting: single experience with 271 elderly/frail patients treated with 3D and IMRT technique

PURPOSE

The purpose of the study was to evaluate the toxicity, local control, overall and disease-free survival of elderly breast cancer (BC) patients treated with adjuvant once-weekly ultra-hypofractionated radiotherapy (RT) either with intensity-modulated RT (IMRT) or 3D conformal RT (3DCRT).

METHODS

From July 2011 to July 2018, BC patients receiving 5.7 Gy once a week for 5 weeks to the whole breast after breast-conserving surgery were considered for the study. Inclusion criteria were: T1-T3 invasive BC, no or limited axillary involvement, age ≥ 65 years or women with commuting difficulties or disabling diseases.

RESULTS

A total of 271 patients were included in the study. Median age was 76 (46-86) years. Most of BC were T1 (77%), while the remaining were T2 (22.2%) and T3 (0.4%). Axillary status was negative in 68.3% of the patients. The only severe acute toxicity (G3) at the end of RT was erythema (0.4%), registered in the 3DCRT group; no G3 edema or epitheliolysis was recorded. With 18 months of median follow-up, severe early-late toxicity (G3) was reported in terms of fibrosis and breast retraction, both with an incidence of 1.4%, mostly in the 3DCRT group. Oncological outcomes at a median follow-up of 2.9 years reported 249/271 (91.9%) patients alive and free from any event and 5 (1.8%) isolated locoregional recurrences. At 3 years, disease-free survival and overall survival were 94.9% and 97.8%, respectively. Breast volume > 500 cm³ was reported as predictive for moderate-severe (≥ G2) acute toxicity.

CONCLUSIONS

Weekly ultra-hypofractionated whole breast RT seems feasible and effective. Toxicity was mild, local control was acceptable, and overall survival was 97.8% at 3 years. Rates of severe toxicity were reduced with the IMRT technique.

Has Hypofractionated Whole-Breast Radiation Therapy Become the Standard of Care in the United States? An Updated Report from National Cancer Database

INTRODUCTION/BACKGROUND

We aimed to update the previous evaluation of hypofractionated whole-breast irradiation (HF-WBI) use over time in the United States and factors related to its adoption for patients undergoing a lumpectomy from 2004 to 2016.

MATERIALS AND METHODS

Among the patients who underwent a lumpectomy, we identified 688,079 patients with early-stage invasive breast cancer and 248,218 patients with ductal carcinoma in situ in the National Cancer Database from 2004 to 2016. We defined HF-WBI as 2.5 to 3.33 Gy/fraction to the breast and conventional fractionated whole-breast irradiation as 1.8 to 2.0 Gy/fraction. We evaluated the trend of HF-WBI use and examined factors associated with HF-WBI use using logistic regression models.

RESULTS

Among invasive cancer patients, the use of HF-WBI increased exponentially from 0.7% in 2004 to 15.6% in 2013 and then to 38.1% in 2016. Among patients with ductal carcinoma in situ, the use of HF-WBI has increased significantly from 0.42% in 2004 to 13.4% in 2013 and then to 34.3% in 2016. Factors found to be associated with HF-WBI use included age, patient geographical location, race/ethnicity, tumor stage, grade, treating facility type, and volume.

CONCLUSION

HF-WBI use in the United States has more than doubled from 2013 to 2016. Although its use is close to that of conventional fractionated whole-breast irradiation, HF-WBI is still far from the preferred standard of care in the United States. We identified several patient and facility factors that can impact the uptake of HF-WBI treatment. Microabstract Using the National Cancer Database from 2004 to 2016, we evaluated the trend of hypofractionated whole-breast radiation therapy use and factors associated with use. Use in the United States has more than doubled from 2013 to 2016, but it has not become the standard of care. We identified several patient and facility factors that impact the uptake of hypofractionated whole-breast radiation therapy treatment.

Increasing use of post-mastectomy hypofractionated radiation therapy for breast cancer in Victoria

INTRODUCTION

The aim of this study was to evaluate the use of post-mastectomy hypofractionationed radiation therapy (HFRT) for breast cancer in Victoria, Australia.

METHODS

This is a population-based cohort of women with breast cancer who received post-mastectomy RT to the chest wall with or without nodal irradiation between 2012 and 2017. HFRT was defined as <25 fractions of RT. Data were captured in the Victorian Radiotherapy Minimum Dataset (VRMDS). The changing pattern of HFRT use was evaluated using the Cochran-Armitage test. Patient-, treatment- and institutional-related factors associated with HFRT use were evaluated using multivariable logistic regression.

RESULTS

Two thousand and twenty-one women were included in this study, of which 238 (12%) received HFRT. This increased from 8% in 2012 to 18% in 2017 (P-trend < 0.001). Older women were more likely to have HFRT (26% in women above 70 years vs 6% in women under 50 years; P < 0.001). Women who did not have nodal irradiation were more likely to have HFRT than those who did (18% vs 9% respectively; P < 0.001). In multivariate analyses, the progressive increase in HFRT use over time remained statistically significant - women treated in 2017 were four times more likely to receive HFRT than those treated in 2012 (95% CI = 2.1-7.7; P < 0.001). Other factors independently associated with increased likelihood of HFRT use included increasing age at RT, and lack of nodal irradiation.

CONCLUSION

In this first Australian study evaluating the use of post-mastectomy HFRT, we observed increasing HFRT use in Victoria over time. We anticipate this rising trend will continue in the coming years.

Differences in Time Burden across Local Therapy Strategies for Early-stage Breast Cancer

"Time burden" (time required during treatment) is relevant when choosing a local therapy option for early-stage breast cancer but has not been rigorously studied. We compared the time burden for three common local therapies for breast cancer: (1) lumpectomy plus whole-breast irradiation (Lump+WBI), (2) mastectomy without radiation or reconstruction (Mast alone), and (3) mastectomy without radiation but with reconstruction (Mast+Recon).

Methods

Using the MarketScan database, we identified 35,406 breast cancer patients treated from 2000 to 2011 with these local therapies. We quantified the total time burden as the sum of inpatient days (inpatient-days), outpatient days excluding radiation fractions (outpatient-days), and radiation fractions (radiation-days) in the first two years postdiagnosis. Multivariable regression evaluated the effect of local therapy on inpatient-days and outpatient-days adjusted for patient and treatment covariates.

Results

Adjusted mean number of inpatient-days was 1.0 for Lump+WBI, 2.0 for Mast alone, and 3.1 for Mast+Recon (P < 0.001). Adjusted mean number of outpatient-days was 42.9 for Lump+WBI, 42.2 for Mast alone, and 45.8 for Mast+Recon (P < 0.001). The mean number of radiation-days for Lump+WBI was 32.4. Compared with Mast+Recon (48.9 days), total adjusted time burden was 4.7 days shorter for Mast alone (44.2 days) and 27.4 days longer for Lump+WBI (76.3 days). However, use of a 15 fraction WBI regimen would reduce the time burden differential between Lump+WBI and Mast+Recon to just 10.0 days.

Conclusions

Although Mast+Recon confers the highest inpatient and outpatient time burden, Lump+WBI carries the highest total time burden. Increased use of hypofractionation will reduce the total time burden for Lump+WBI.

Hypofractionated Radiation Therapy (HFRT) of Breast/Chest Wall and Regional Nodes in Locally Advanced Breast Cancer: Toxicity Profile and Survival Outcomes in Retrospective Monoistitutional Study

AIM

To evaluate the efficacy and safety of hypofractionated radiation therapy (HFRT) of the breast/chest wall and regional nodes in patients with locally advanced breast cancer and positive lymph nodes.

MATERIALS AND METHODS

One hundred and twenty-two patients treated between October 2016 and March 2020 with HFRT were retrospectively reviewed. A total dose of 42.4 Gy was delivered to the chest wall and lymph nodes in 16 fractions of 2.65 Gy each, using the IMRT technique. Patients treated with breast-conserving surgery received an overdose (concomitant boost of 3 Gy daily) with the SIB (Simultaneous Integrated Boost) technique.

RESULTS

Median age at diagnosis was 58 years (range 34-86 years) and median follow-up was 22 months (range 6-48 months). Overall survival (OS) at 1, 2 and 3 years was 100%, 97.3% and 90%, respectively. Disease-free survival (DFS) at 1, 2, and 3 years was 91.4%, 87%, and 84.8%, respectively. Distant metastasis-free survival (MFS) at 1, 2 and 3 years was 93.1%, 88% and 85.7%, respectively. Two patients (1.6%) experienced local recurrence on the chest wall during FUP. Twenty-one patients (17%) showed a grade 2 dermal toxicity, no grade 3 acute skin toxicity was found. Sixteen patients (13%) showed early-stage arm lymphedema (grade ≤ 2). Twenty-three patients (19%) showed a grade 2 late skin toxicity. Twenty patients (16%) had grade ≤ 2 late arm lymphedema.

CONCLUSION

Given the excellent local control, survival rates and the low toxicity profile demonstrated, HFRT could be considered a valid therapeutic option in patients with locally advanced breast cancer.

Maintaining Contour with a Three-dimensional Interstitial Tissue Marker in 134 Lumpectomies

Breast-conserving surgery (BCS) is meant to preserve the natural appearance of the breast; however, tissue volume deficits cannot always be compensated by soft tissue mobilization. A three-dimensional (3D) interstitial tissue marker (BioZorb) was designed to delineate the lumpectomy cavity for targeting boost irradiation, but an unexpected secondary benefit may be in guiding wound contraction and restoring contour to the lumpectomy bed. We analyze tissue volume excised at the time of lumpectomy as a function of device size selected.

Methods

In total, 134 consecutive lumpectomy patients implanted with BioZorb between May 2015 and February 2020 were retrospectively analyzed for tissue volume excised, device size used, location, and re-operation rates, including explantation of the device.

Results

An estimated 113 patients underwent device implantation at initial lumpectomy, and 21 at margin re-excision. Twenty-seven patients underwent re-excision, while 14 elected mastectomy for positive margins following insertion; 22 had the same device reimplanted. Mean lumpectomy volume was 79.0 cm³ (range 10.3-275.8 cm³) during the first implant procedure. Large-volume lumpectomies, averaging 136.5 cm³, were associated with selection of larger devices, which aided in restoring volume and maintaining breast contour. Three (2.2%) patients requested removal of the device.

Conclusions

BioZorb implantation can be a safe and useful oncoplastic technique for restoring volume with BCS. Large-volume lumpectomies can be performed without contouring defects using the device. An unexpected secondary benefit of the device may be scaffolding for wound contraction.

Can the Adoption of Hypofractionation Guidelines Expand Global Radiotherapy Access? An Analysis for Breast and Prostate Radiotherapy

PURPOSE

The limited radiotherapy resources for global cancer control have resulted in increased interest in developing time- and cost-saving innovations to expand access to those resources. Hypofractionated regimens could minimize cost and increase access for limited-resource countries. In this investigation, we estimated the percentage cost-savings per radiotherapy course and increased radiotherapy access in African countries after adopting hypofractionation for breast and prostate radiotherapy. For perspective, results were compared with high-income countries.

METHODS

The cost and course of breast and prostate radiotherapy for conventional and hypofractionated regimens in low-resource facilities were calculated using the Radiotherapy Cost Estimator tool developed by the International Atomic Energy Agency (IAEA) and then compared with another activity-based costing model. The potential maximum cost savings in each country over 7 years for breast and prostate radiotherapy were then estimated using cancer incidence data from the Global Cancer Observatory database with use rates applied. The increase in radiotherapy access was estimated by current national capacities from the IAEA directory.

RESULTS

The estimated cost per course of conventional and hypofractionated regimens were US$2,232 and $1,339 for breast treatment, and $3,389 and $1,699 for prostate treatment, respectively. The projected potential maximum cost savings with full hypofractionation implementation were $1.1 billion and $606 million for breast and prostate treatment, respectively. The projected increase of radiotherapy access due to implementing hypofractionation varied between +0.3% to 25% and +0.4% to 36.0% for breast and prostate treatments, respectively.

CONCLUSION

This investigation demonstrates that adopting hypofractionated regimens as standard treatment of breast and prostate cancers can result in substantial savings and increase radiotherapy access in developing countries. Given reduced delivery cost and treatment times, we anticipate a substantial increase in radiotherapy access with additional innovations that will allow progressive hypofractionation without compromising quality.

Five-fraction Radiotherapy for Breast Cancer: FAST-Forward to Implementation

INTRODUCTION

The phase 3 FAST-Forward trial reported outcomes for 26 and 27 Gy schedules delivered in 5 fractions over 1 week versus 40 Gy in 15 fractions over 3 weeks in 4000 patients. We discuss concerns raised by the radiotherapy community in relation to implementing this schedule.

IPSILATERAL BREAST TUMOUR RELAPSE (IBTR)

Published estimated 5-year IBTR with 95% CI after 40 Gy in 15 fractions was 2.1% (95% CI 1.4-3.1), 1.7% (1.2-1.6) after 27 Gy and 1.4% (0.2-2.2) after 26 Gy, emphatically showing non-inferiority of the 5-fraction regimens. Subgroup analyses comparing IBTR in 26 Gy versus 40 Gy show no evidence of differential effect regarding age, grade, pathological tumour size, nodal status, tumour bed boost, adjuvant chemotherapy, HER2 status and triple negative status. The number of events in these analyses is small and results should be interpreted with caution. There was only 1 IBTR event post-mastectomy.

NORMAL TISSUE EFFECTS

The 26 Gy schedule, on the basis of similar NTE to 40 Gy in 15 fractions, is the recommended regimen for clinical implementation. There is a low absolute rate of moderate/marked NTE, these are predominantly moderate not severe change. Subgroup analyses comparing clinician-assessed moderate or marked adverse effect for 26 Gy versus 40 Gy show no evidence of differential effects according to age, breast size, surgical deficit, tumour bed boost, or adjuvant chemotherapy.

RADIOBIOLOGICAL CONSIDERATIONS

The design of the FAST-Forward trial does not control for time-related effects, and the ability to interpret clinical outcomes in terms of underlying biology is limited. There could conceivably be a time-effect for tumour control. A slight reduction in α/β estimate for the late normal tissue effects of test regimens might be a chance effect, but if real could reflect fewer consequential late effects due to lower rates of moist desquamation.

CONCLUSION

The 26 Gy 5-fraction daily regimen for breast radiotherapy can be implemented now.

Physician trajectories of abandoning long-course breast radiotherapy and their cost impact

OBJECTIVE

To examine variation in trajectories of abandoning conventionally fractionated whole-breast irradiation (CF-WBI) for adjuvant breast radiotherapy among physician peer groups and the associated cost implications.

DATA SOURCES

Medicare claims data were obtained from the Chronic Conditions Data Warehouse for fee-for-service beneficiaries with breast cancer in 2011-2014.

STUDY DESIGN

We used social network methods to identify peer groups of physicians that shared patients. For each physician peer group in each time period (T1 = 2011-2012 and T2 = 2013-2014), we calculated a risk-adjusted rate of CF-WBI use among eligible women, after adjusting for patient clinical characteristics. We applied a latent class growth analysis to these risk-adjusted rates to identify distinct trajectories of CF-WBI use among physician peer groups. We further estimated potential savings to the Medicare program by accelerating abandonment of CF-WBI in T2 using a simulation model.

DATA COLLECTION/EXTRACTION METHODS

Use of conventionally fractionated whole-breast irradiation was determined from Medicare claims among women ≥ 66 years of age who underwent adjuvant radiotherapy after breast conserving surgery.

PRINCIPAL FINDINGS

Among 215 physician peer groups caring for 16 988 patients, there were four distinct trajectories of abandoning CF-WBI: (a) persistent high use (mean risk-adjusted utilization rate: T1 = 94.3%, T2 = 90.6%); (b) decreased high use (T1 = 81.3%, T2 = 65.3%); (c) decreased medium use (T1 = 60.1%, T2 = 44.0%); and (d) decreased low use (T1 = 31.6%, T2 = 23.6%). Peer groups with a smaller proportion of patients treated at free-standing radiation facilities and a larger proportion of physicians that were surgeons tended to follow trajectories with lower use of CF-WBI. If all physician peer groups had practice patterns in T2 similar to those in the "decreased low use" trajectory, the Medicare program could save $83.3 million (95% confidence interval: $58.5 million-$112.2 million).

CONCLUSIONS

Physician peer groups had distinct trajectories of abandoning CF-WBI. Physician composition and setting of radiotherapy were associated with the different trajectories. Distinct practice patterns across the trajectories had important cost implications.

Weathering the Storm: Managing Older Adults With Breast Cancer Amid COVID-19 and Beyond

Caring for older patients with breast cancer presents unique clinical considerations because of preexisting and competing comorbidity, the potential for treatment-related toxicity, and the consequent impact on functional status. In the context of the COVID-19 pandemic, treatment decision making for older patients is especially challenging and encourages us to refocus our treatment priorities. While we work to avoid treatment delays and maintain therapeutic benefit, we also need to minimize the risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposures, myelosuppression, general chemotherapy toxicity, and functional decline. Herein, we propose multidisciplinary care considerations for the aging patient with breast cancer, with the goal to promote a team-based, multidisciplinary treatment approach during the COVID-19 pandemic and beyond. These considerations remain relevant as we navigate the “new normal” for the approximately 30% of breast cancer patients aged 70 years and older who are diagnosed in the United States annually and for the thousands of older patients living with recurrent and/or metastatic disease.

Comparing the effect of distance to treatment facility on reconstruction and breast conservation therapy for early-stage invasive ductal carcinoma between the nation and the mountain region

BACKGROUND

Our objective is to evaluate the effect of distance to facility on the use of breast conservation therapy and reconstruction for early stage breast cancer.

METHODS

Utilizing the National Cancer Database, we identified females, age <65, with Stage I invasive ductal carcinoma from 2004 to 2015. Using logistic regression, we compared radiation, mastectomy, and reconstruction treatment patterns. A subgroup analysis was performed within the mountain region (MR).

RESULTS

Nationwide, there are decreasing odds of radiation, increasing odds of mastectomy, and increasing odds of reconstruction. Patients living farther were less likely to receive radiation, more likely to undergo mastectomy, with no effect on reconstruction. Within the MR, patients living farther from their facility were less likely to receive radiation, more likely to undergo mastectomy, however, they were less likely to undergo reconstruction.

CONCLUSIONS

Nationwide and within the MR, patients living farther from their facility are less likely to receive radiation and more likely to undergo mastectomy. There is a disparity between the MR and the nation in use of reconstruction for this population.

Radiation Oncologists' Views on Breast Radiation Therapy Guidelines: Utilizing an Online Q&A Platform to Assess Current Views on Whole-Breast Irradiation Therapy

INTRODUCTION

Poor adherence to the 2011 American Society for Radiation Oncology (ASTRO) evidence-based guideline on whole-breast irradiation (WBI) has been reported. We utilized theMednet to assess the views of the updated 2018 guideline among radiation oncologists (ROs).

METHODS

We identified 11 questions asked by community ROs on theMednet, a web-based platform, between October 27, 2014 and May 2, 2017 that were updated in the 2018 guideline. New answers provided by senior authors of the 2018 guideline, cited guidelines, and polls to survey ROs were disseminated in 3 theMednet's newsletters between March 16, 2018 and May 1, 2018. Any question with less than 60% consensus was resubmitted on October 9, 2019 and assessed on February 13, 2020.

RESULTS

A total of 792 ROs responded to the initial surveys. In each survey, the answer choice(s) that received the majority of the votes aligned with the 2018 guideline. The strongest consensus was for the use of hypofractionated (HF)-WBI regardless of histology (97%), followed by HF-WBI boost dose (92%), molecular subtype (90%), grade (88%), and concurrent use of trastuzumab (87%). The least consensus was for age at which HF-WBI should be offered with 53% of respondents, specifically 73% of academic ROs versus 47% of community ROs (P = .001), agreeing with the guideline. The re-submitted survey 19 months later showed 77% of 287 new respondents now agreed with the guideline regarding age.

CONCLUSION

The majority of ROs concur with the 2018 WBI guideline in theMednet surveys, with better agreement among academic ROs than community ROs for certain components of the guideline. Further research into the different practice patterns may optimize patient care.

Appropriate margin for planning target volume for breast radiotherapy during deep inspiration breath-hold by variance component analysis

BACKGROUND

This study aimed to quantify errors by using a cine electronic portal imaging device (cine EPID) during deep inspiration breath-hold (DIBH) for left-sided breast cancer and to estimate the planning target volume (PTV) by variance component analysis.

METHODS

This study included 25 consecutive left-sided breast cancer patients treated with whole-breast irradiation (WBI) using DIBH. Breath-holding was performed while monitoring abdominal anterior-posterior (AP) motion using the Real-time Position Management (RPM) system. Cine EPID was used to evaluate the chest wall displacements in patients. Cine EPID images of the patients (309,609 frames) were analyzed to detect the edges of the chest wall using a Canny filter. The errors that occurred during DIBH included differences between the chest wall position detected by digitally reconstructed radiographs and that of all cine EPID images. The inter-patient, inter-fraction, and intra-fractional standard deviations (SDs) in the DIBH were calculated, and the PTV margin was estimated by variance component analysis.

RESULTS

The median patient age was 55 (35-79) years, and the mean irradiation time was 20.4 ± 1.7 s. The abdominal AP motion was 1.36 ± 0.94 (0.14-5.28) mm. The overall mean of the errors was 0.30 mm (95% confidence interval: - 0.05-0.65). The inter-patient, inter-fraction, and intra-fractional SDs in the DIBH were 0.82 mm, 1.19 mm, and 1.63 mm, respectively, and the PTV margin was calculated as 3.59 mm.

CONCLUSIONS

Errors during DIBH for breast radiotherapy were monitored using EPID images and appropriate PTV margins were estimated by variance component analysis.