Systematic review and meta-analysis comparing hypofractionated with conventional fraction radiotherapy in treatment of early breast cancer

A comprehensive overview of radiation therapy impacts of various cancer treatments and pivotal role in the immune system

The cancer treatment landscape is significantly evolving, focusing on advanced radiation therapy methods to maximize effectiveness and minimize the adverse effects. Recognized as a pivotal component in cancer and disease treatment, radiation therapy (RT) has drawn attention in recent research that delves into its intricate interplay with inflammation and the immune response. This exploration unveils the underlying processes that significantly influence treatment outcomes. In this context, the potential advantages of combining bronchoscopy with RT across diverse clinical scenarios, alongside the targeted impact of brachytherapy, are explored. Concurrently, radiation treatments serve multifaceted roles such as DNA repair, cell elimination, and generating immune stress signaling molecules known as damage-associated molecular patterns, elucidating their effectiveness in treating various diseases. External beam RT introduces versatility by utilizing particles such as photons, electrons, protons, or carbon ions, each offering distinct advantages. Advanced RT techniques contribute to the evolving landscape, with emerging technologies like FLASH, spatially fractionated RT, and others poised to revolutionize the field. The comprehension of RT, striving for improved treatment outcomes, reduced side effects, and facilitating personalized and innovative treatments for cancer and noncancer patients. After navigating these advancements, the goal is fixed to usher in a new era in which RT is a cornerstone of precision and effectiveness in medical interventions. In summarizing the myriad findings, the review underscores the significance of understanding the differential impacts of radiation approaches on inflammation and immune modulation, offering valuable insights for developing innovative therapeutic interventions that harness the immune system in conjunction with RT.

Efficacy and safety analysis of hypofractionated and conventional fractionated radiotherapy in postoperative breast cancer patients

OBJECTIVES

In this meta-analysis, we conducted a comparative analysis of the safety and efficacy of hypofractionated and conventional fractionated radiotherapy in individuals who had undergone surgery for breast cancer.

METHODS

This study involved a systematic and independent review of relevant research articles published in reputable databases such as PubMed, Embase, Cochrane Library, and Web of Science. Two investigators conducted the review, which included studies published up to January 3, 2023. The quality of the eligible studies was evaluated and data were extracted using Review Manager software 5.4 (RevMan 5.4) to calculate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

The analysis comprised 35 studies and encompassed a collective sample of 18,246 individuals diagnosed with breast cancer. We did not find a statistically significant disparity in efficacy between conventional fractionated (CF) radiotherapy and hypofractionated (HF) radiotherapy regarding local recurrence (LR; OR = 0.91, 95% CI: 0.76-1.09, P = 0.30), disease-free survival (DFS; OR = 1.20, 95% CI: 1.01-1.42, P = 0.03), and overall survival (OS; OR = 1.08, 95% CI: 0.93-1.26, P = 0.28). Concerning safety, there was no significant difference between the HF and CF regimens in terms of breast pain, breast atrophy, lymphedema, pneumonia, pulmonary fibrosis, telangiectasia, and cardiotoxicity. However, the HF regimen resulted in lower skin toxicity (OR = 0.43, 95% CI: 0.33-0.55, P < 0.01) and improved patient fatigue outcomes (OR = 0.73, 95% CI: 0.60 - 0.88, P < 0.01).

CONCLUSIONS

Although there is no substantial difference in LR, DFS, OS, or many other side effects between the HF and CF regimens, the HF regimen reduces skin toxicity and relieves patient fatigue. If these two issues need to be addressed in clinical situations, the HF regimen may be a superior alternative to conventional radiotherapy in postoperative breast cancer patients.

Facing problems in radiotherapy for breast cancer patients in Yogyakarta, Indonesia: A cohort retrospective study

BACKGROUND

The aim of this study is to explore problems in radiotherapy for breast cancer patients in Yogyakarta, Indonesia, focusing on overall treatment time (OTT) and completion rate.

METHODS

A retrospective cohort study was conducted based on data from the Insurance Unit at a tertiary hospital in Yogyakarta, Indonesia. The study included all female outpatients with breast cancer who were treated with radiotherapy from January to December 2017 and met the inclusion criteria. The primary outcomes were OTT and completion rate. The secondary outcomes included the number of radiotherapy fractions, radiotherapy doses, number of radiotherapy interruption days, and reasons for radiotherapy interruption. The chi-squared and Mann-Whitney U tests were used to assess the differences in outcomes between two insurance schemes (JKN-PBI (Beneficiaries of Health Insurance Contribution Assistance) and JKN-NON-PBI (Non-Beneficiaries of Health Insurance Contribution Assistance)).

RESULTS

The sample included 285 breast cancer patients (mean age: 53 years). The median OTT was 38 days (IQR: 17-48 days), with 123 (43.2%) patients having prolonged OTT. The completion rate was 57.9%. No significant differences in OTT (44.4% vs. 35.7%, p = 0.445) and completion rate (57.2% vs. 61.9%, p = 0.569) were found between the JKN-NON-PBI and JKN-PBI groups, respectively. In all, the data reported 3,022 interrupted days of radiotherapy across a total of 227 patients. The most common reason for radiotherapy interruption was unknown.

CONCLUSION

There are problems in timely delivery and low completion rate of radiotherapy among breast cancer patients in Indonesia. There are no significant differences in OTT and completion rate between the insurance schemes.

Effectiveness of hypofractionated and normofractionated radiotherapy in a triple‐negative breast cancer model

Breast cancer (BC) is one of the most diagnosed malignant carcinomas in women with a triple-negative breast cancer (TNBC) phenotype being correlated with poorer prognosis. Fractionated radiotherapy (RT) is a central component of breast cancer management, especially after breast conserving surgery and is increasingly important for TNBC subtype prognosis. In recent years, moderately hypofractionated radiation schedules are established as a standard of care, but many professionals remain skeptical and are concerned about their efficiency and side effects. In the present study, two different triple-negative breast cancer cell lines, a non-malignant breast epithelial cell line and fibroblasts, were irradiated daily under normofractionated and hypofractionated schedules to evaluate the impact of different irradiation regimens on radiation-induced cell-biological effects. During the series of radiotherapy, proliferation, growth rate, double-strand DNA break-repair (DDR), cellular senescence, and cell survival were measured. Investigated normal and cancer cells differed in their responses and receptivity to different irradiation regimens, indicating cell line/cell type specificity of the effect. At the end of both therapy concepts, normal and malignant cells reach almost the same endpoint of cell count and proliferation inhibition, confirming the clinical observations in the follow-up at the cellular level. These result in cell lines closely replicating the irradiation schedules in clinical practice and, to some extent, contributing to the understanding of growth rate or remission of tumors and the development of fibrosis.

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.

Incidence of radiodermatitis in breast cancer patients during hypofractionated radiotherapy

ABSTRACT Objective: To analyze the incidence, dose of occurrence, grade, severity, and associated risk factors for the development of radiodermatitis, by area of the irradiated breast, in women with breast cancer, during hypofractionated radiotherapy. Method: Observational, prospective, and longitudinal study, according to the guidelines of the Strengthening the Reporting of Observational studies in Epidemiology, carried out between May 2019 and May 2021. Results: A total of 104 women participated in the study, and 73.1% (95%CI: 64–82) developed signs of radiodermatitis during treatment. The majority (63.5%, 95%CI: 54–73) developed erythema in the axillary region with about 36.5 Grays. Women with large breasts and statin users are more likely to develop radiodermatitis. However, women with Phototype III skin color classification (light brown skin) are less likely to develop radiodermatitis, with skin color being a protective factor. Conclusion: The incidence of radiodermatitis in women with breast cancer during hypofractionated radiotherapy is significant. Therefore, the development of protocols for the management of this radiotoxicity is suggested, considering the cumulative dose and associated risk factors.

Incidência de radiodermatite em pacientes com câncer de mama durante a radioterapia hipofracionada

RESUMO Objetivo: Analisar a incidência, a dose de ocorrência, o grau, a severidade e os fatores de risco associados para o desenvolvimento de radiodermatite, por área da mama irradiada, em mulheres com câncer de mama, durante a radioterapia hipofracionada. Método: Estudo observacional, prospectivo e longitudinal, conforme diretrizes do Strengthening the Reporting of Observational studies in Epidemiology, realizado entre maio de 2019 e maio de 2021. Resultados: Participaram do estudo 104 mulheres, 73,1% (IC95%: 64–82) desenvolveram sinais de radiodermatite durante o tratamento. A maioria (63,5%, IC95%: 54–73) desenvolveu eritema na região axilar com cerca de 36,5 Grays. Mulheres com mamas volumosas e usuárias de estatinas possuem maior chance de desenvolver radiodermatite. Entretanto, mulheres com a cor da pele classificada como Fototipo III (pele morena clara) possuem menor chance de desenvolver radiodermatite, sendo a cor da pele um fator protetor. Conclusão A incidência de radiodermatite em mulheres com câncer de mama durante a radioterapia hipofracionada é expressiva. Sugere-se, portanto, o desenvolvimento de protocolos para o manejo desta radiotoxicidade, considerando a dose cumulativa e fatores de risco associados.

Individual Radiosensitivity as a Risk Factor for the Radiation-Induced Acute Radiodermatitis

Background: Up to 95% of irradiated patients suffer from ionizing radiation (IR) induced early skin reaction, acute radiation dermatitis (ARD). Some experts think that additional skin hydration can reduce acute skin reactions. Individual radiosensitivity (IRS) determined from lymphocytes may help to predict acute radiation toxicity. The purpose of this study is to evaluate the clinical manifestation of ARD in different skincare groups during whole breast radiotherapy depending on IRS and other risk factors. Methods: A total of 108 early-stage breast cancer patients were randomized into best supportive care (BSC) and additional skincare (ASC) groups. IRS was evaluated using a G2 assay modified with caffeine-induced G2 checkpoint arrest. All patients received a 50 Gy dose to the breast planning target volume (PTV). Clinical assessment of ARD symptoms according to the CTCAE grading scale was performed once a week. Results: IRS was successfully determined for 91 out of 108 patients. A total of 10 patients (11%) had normal IRS, 47 patients (52%) were categorized as radiosensitive, and 34 (37%) as highly radiosensitive. There was no significant difference in the manifestation of ARD between patient groups by skincare or IRS. According to logistic regression, patients with bigger breasts were prone to more severe ARD (p = 0.002). Conclusions: The additional skincare did not improve skin condition during RT. A total of 89% of patients had increased radiosensitivity. IRS determined before RT did not show the predictive value for the manifestation of ARD. Logistic regression revealed that breast volume was the most significant risk factor for the manifestation of ARD.

Comparing Hypofractionated With Conventional Fractionated Radiotherapy After Breast-Conserving Surgery for Early Breast Cancer: A Meta-Analysis of Randomized Controlled Trials

Background

The purpose of this meta-analysis was to compare the safety and efficacy between hypofractionated and conventional fractionation radiotherapy in patients with early-stage breast cancer after breast-conserving surgery.

Methods

We conducted a comprehensive search of PubMed, Embase, Web of Science, and the Cochrane Library to identify relevant randomized controlled trials (RCTs) published before February 2021. At the same time, the hazard ratio (HR), risk ratio (RR), and 95% confidence interval (CI) were calculated to evaluate local recurrence (LR), relapse-free survival (RFS), overall survival (OS), adverse events, and cosmetic outcomes.

Results

A total of 14 articles were included in this meta-analysis. Four thousand eight hundred and sixty-nine patients were randomly assigned to the control group to receive conventional radiotherapy (CFRT); 6,072 patients were randomly assigned to the experimental group and treated with hypofractionated radiotherapy (HFRT). The results showed that there was no statistical difference between HFRT and CFRT in LR (HR = 0.99, 95%CI = 0.97-1.02, p = 0.476), RFS (HR = 0.99, 95%CI = 0.97-1.02, p = 0.485), OS (HR = 1.00, 95%CI = 0.97-1.03, p = 0.879), and cosmetic outcomes (RR = 1.03, 95%CI = 0.95-1.12, p = 0.53). In addition, HFRT showed fewer severe adverse reactions such as acute skin toxicity, induration, breast atrophy, and pain.

Conclusion

Our results suggest that there is no statistical difference between HFRT and CFRT in terms of LR, RFS, OS, and cosmetic outcomes. HFRT reduces the risk of developing toxicity reactions compared to CFRT. HFRT may be a better option for patients with early breast cancer after breast-conserving surgery.

A radiobiological comparison of hypo-fractionation versus conventional fractionation for breast cancer 3D-conformal radiation therapy

Background

The present research was aimed to compare the toxicity and effectiveness of conventional fractionated radiotherapy versus hypo-fractionated radiotherapy in breast cancer utilizing a radiobiological model.

Materials and methods

Thirty-five left-sided breast cancer patients without involvement of the supraclavicular and axillary lymph nodes (with the nodal stage of N0) that had been treated with conventional or hypo-fractionated were incorporated in this study. A radiobiological model was performed to foretell normal tissue complication probability (NTCP) and tumor control probability (TCP).

Results

The data represented that TCP values for conventional and hypo-fractionated regimens were 99.16 ± 0.09 and 95.96 ± 0.48, respectively (p = 0.00). Moreover, the NTCP values of the lung for conventional and hypo-fractionated treatment were 0.024 versus 0.13 (p = 0.035), respectively. Also, NTCP values of the heart were equal to zero for both regimens.

Conclusion

In summary, hypo-fractionated regimens had comparable efficacy to conventional fraction radiation therapy in the case of dosimetry parameters for patients who had left breast cancer. But, utilizing the radiobiological model, conventional fractionated regimens presented better results compared to hypo-fractionated regimens.

Appraising the quality of meta-analysis for breast cancer treatment in the adjuvant setting: A systematic review

INTRODUCTION

Breast cancer is the tumor with highest incidence in women worldwide and adjuvant treatment is extremely important to achieve disease control. Given the relevance of systematic reviews, their rigor should be warranted to avoid biased conclusions. Our objective was to investigate the methodological quality of meta-analysis of early breast cancer adjuvant treatment.

MATERIAL AND METHODS

Comprehensive searches were performed using electronic databases from 1/1/2007 to 11/12/2018. All studies identified as a systematic review with meta-analysis investigating the efficacy of breast cancer adjuvant treatments were included. Two reviewers independently assessed titles and abstracts, then full-texts for eligibility. Quality was assessed using the Assessing the Methodological Quality of Systematic Reviews (AMSTAR) version 2 tool.

RESULTS

Of 950 citations retrieved, 66 studies (7.0%) were deemed eligible. Methodological quality was highly variable, median AMSTAR score 8.5 (IQR 7-9.5) and range 0-16. There was a weak positive correlation between journal impact factor and AMSTAR score (r = 0.17) and citation rate and AMSTAR score (r = 0.16). Cochrane Systematic Reviews were of higher quality than reviews from other journals. Overall confidence was critically low for 61 (92.4%) studies, and the least well-reported domains were the statement of conflict of interest and funding source for the included studies (4.6%), the report of a pre-defined study protocol (15.2%), and the description of details of excluded studies (6.1%).

CONCLUSIONS

Our findings reinforce concerns about the design, conduction and interpretation of meta-analysis in current literature. Methodological quality should be carefully considered and journal editors, decision makers and readers in general, must follow a critical approach to this studies.

Recommendations for hypofractionated whole-breast irradiation

This recommendation consensus for hypofractionated whole-breast radiotherapy (RT) was organized by the Brazilian Society of Radiotherapy (SBRT) considering the optimal scenario for indication and safety in the technology applied. All controversies and contraindication matters (hypofractionated RT in patients who underwent chemotherapy [CT], hypofractionated RT in lymphatic drainage, hypofractionated RT after mastectomy with or without immediate reconstruction, boost during surgery, hypofractionated RT in patients under 50 years old, hypofractionated RT in large breasts, hypofractionated RT in histology of carcinoma in situ [DCIS]) was discussed during a meeting in person, and a consensus was reached when there was an agreement of at least 75% among panel members. The grade for recommendation was also suggested according to the level of scientific evidence available, qualified as weak, medium, or strong. Thus, this consensus will aid Brazilian radiotherapy experts regarding indications and particularities of this technique as a viable and safe alternative for the national reality.

Hypofractionated radiation treatment in the management of breast cancer

INTRODUCTION

The standard treatment for early-stage breast cancer is breast conservation therapy, consisting of breast conserving surgery followed by adjuvant radiation treatment (RT). Conventionally-fractionated whole breast irradiation (CF-WBI) has been the standard RT regimen, but recently shorter courses of hypofractionated whole breast irradiation (HF-WBI) have been advocated for patient convenience and reduction in healthcare costs and resources. Areas covered: This review covers the major randomized European and Canadian trials comparing HF-WBI to CF-WBI with long-term follow-up, as well as additional recently closed randomized trials that further seek to define the applicability of HF-WBI in clinical practice. Randomized data is summarized in terms of clinical utility and for a variety of clinical applications. Recently published consensus guidelines and practical implementation of HF-WBI including its broader effect on the healthcare system are reviewed. Finally, an assessment of the emerging evidence in support of hypofractionation for locally advanced disease is presented. Expert commentary: HF-WBI has replaced CF-WBI as the accepted standard of care in most women with early-stage breast cancer who do not require regional nodal irradiation. Early data supports the continued study of hypofractionation in the locally advanced setting, however broad adoption awaits longer follow-up and additional data from ongoing clinical trials.

Recent Developments in Radiation Oncology: An Overview of Individualised Treatment Strategies in Breast Cancer

Radiation therapy (RT) for breast cancer has dramatically changed over the past years, leading to individualized risk-adapted treatment strategies. Historically, the choice of RT regimen was limited to conventional fractionation protocols using standard tangential fields. Nowadays, technological and technical improvements in modern RT have added a variety of other RT modalities, different fractionation schedules, and individualised treatment volumes to the portfolio of breast RT. This review aims to give a short overview on the main topics which have recently found their way into clinical practice: hypofractionated treatment protocols, accelerated partial breast irradiation (APBI) for low-risk patients, deep inspiration breath hold (DIBH) for maximal heart protection, extent of regional nodal irradiation for high-risk patients, and the implementation of new radiation techniques such as intensity modulated RT (IMRT) and volumetric modulated RT (VMAT).

Comparison of the average surviving fraction model with the integral biologically effective dose model for an optimal irradiation scheme

In this paper, we compare two radiation effect models: the average surviving fraction (ASF) model and the integral biologically effective dose (IBED) model for deriving the optimal irradiation scheme and show the superiority of ASF. Minimizing the effect on an organ at risk (OAR) is important in radiotherapy. The biologically effective dose (BED) model is widely used to estimate the effect on the tumor or on the OAR, for a fixed value of dose. However, this is not always appropriate because the dose is not a single value but is distributed. The IBED and ASF models are proposed under the assumption that the irradiation is distributed. Although the IBED and ASF models are essentially equivalent for deriving the optimal irradiation scheme in the case of uniform distribution, they are not equivalent in the case of non-uniform distribution. We evaluate the differences between them for two types of cancers: high α/β ratio cancer (e.g. lung) and low α/β ratio cancer (e.g. prostate), and for various distributions i.e. various dose-volume histograms. When we adopt the IBED model, the optimal number of fractions for low α/β ratio cancers is reasonable, but for high α/β ratio cancers or for some DVHs it is extremely large. However, for the ASF model, the results keep within the range used in clinical practice for both low and high α/β ratio cancers and for most DVHs. These results indicate that the ASF model is more robust for constructing the optimal irradiation regimen than the IBED model.

Data-Based Radiation Oncology: Design of Clinical Trials in the Toxicity Biomarkers Era

The ability to stratify patients using a set of biomarkers, which predict that toxicity risk would allow for radiotherapy (RT) modulation and serve as a valuable tool for precision medicine and personalized RT. For patients presenting with tumors with a low risk of recurrence, modifying RT schedules to avoid toxicity would be clinically advantageous. Indeed, for the patient at low risk of developing radiation-associated toxicity, use of a hypofractionated protocol could be proposed leading to treatment time reduction and a cost-utility advantage. Conversely, for patients predicted to be at high risk for toxicity, either a more conformal form or a new technique of RT, or a multidisciplinary approach employing surgery could be included in the trial design to avoid or mitigate RT when the potential toxicity risk may be higher than the risk of disease recurrence. In addition, for patients at high risk of recurrence and low risk of toxicity, dose escalation, such as a greater boost dose, or irradiation field extensions could be considered to improve local control without severe toxicities, providing enhanced clinical benefit. In cases of high risk of toxicity, tumor control should be prioritized. In this review, toxicity biomarkers with sufficient evidence for clinical testing are presented. In addition, clinical trial designs and predictive models are described for different clinical situations.

Predictive parameters in hypofractionated whole-breast 3D conformal radiotherapy according to the Ontario Canadian trial

AIM

To evaluate the possible role of dosimetric parameters according Normal Tissue Complication Probability (NTCP) model as predictive of late toxicity and cosmesis in hypofractionated whole-breast three-dimensional conformal radiotherapy.

PATIENTS AND METHODS

A retrospective analysis on 215 consecutive early breast cancer patients treated with breast conserving surgery and adjuvant hypofractionated whole-breast radiotherapy (according the Ontario Canadian trial), with a 6 years median follow-up was conducted. To assess the impact of 10%-20% dose hotspots on different percent values of planning target volume (PTV) of the breast, we retrospectively employed the NTCP model of Lyman. PTV breast (PTVbr), V110 were identified. For statistical analysis the χ² and paired t-test were used to find a correlation between late skin and subcutaneous toxicity and cosmetic outcome with dosimetrical parameters Multivariate analysis was performed with the aim to assess independently the impact of dosimetric and clinical parameters on late toxicity and cosmesis using Pearson's covariance.

RESULTS

Late skin toxicity was recorded in 47/215 (22%); and G3 toxicity occurred in 11 patients (5%). Cosmesis with excellent-good score was found in 172 patients (80%) while fair-poor score was found in 43 patients (20%). In univariate χ² analysis the V110 >10% of the PTV breast significantly correlated with higher toxicity (P<0.005, OR 9.60 [CI 3.89-23.72]). Cosmesis related to V110 >10% and PTV breast volume over 1,300 cc was significant at multivariate analysis (P<0.005, OR 6.07 [CI 2.36-15.59]).

CONCLUSION

To safely use one of the most important whole-breast hypofractionated radiotherapy schedules, we found some predictive paramaters on the basis of NTCP model by Lyman. These parameters may be useful in selection of elegible patients.

Hypofractionated whole breast radiotherapy in breast conservation for early-stage breast cancer: a systematic review and meta-analysis of randomized trials

PURPOSE

Breast conservation therapy (BCT) for early-stage breast cancer involves lumpectomy followed by whole breast radiotherapy, which can involve either standard fractionation (SRT) or accelerated fractionation (ART). This systematic review and meta-analysis was performed to determine whether any benefit exists for ART or SRT.

MATERIALS AND METHODS

We searched MEDLINE (1966-2014), all seven databases of the Cochrane Library (1968-2014), EMBASE (1974-2014), clinicaltrials.gov, ISRCTN, WHO ICTRP, and meeting abstracts in the Web of Science Core Collection (1900-2014). RCTs comparing SRT to ART among women undergoing BCT with stage T1-T2 and/or N1 breast cancer or carcinoma in situ were included. Follow-up was 30 days for acute toxicity, or three years for disease control and late toxicity.

RESULTS

13 trials with 8189 participants were included. No differences were observed in local failure (n = 7 trials; RR 0.97; 95% CI 0.78-1.19, I ² = 0%), locoregional failure, (n = 8 trials; RR 0.86; 95% CI 0.63-1.16, I ² = 0%), or survival (n = 4 trials; RR 1.00; 95% CI 0.85-1.17, I ² = 0%). ART was associated with significantly less acute toxicity (n = 5 trials; RR 0.36; 95% CI 0.21-0.62, I ² = 20%), but no difference in late cosmesis (RR 0.95; 95% CI 0.81-1.12, I ² = 54%).

CONCLUSIONS

ART use does not reduce disease control or worsen long-term cosmetic outcome, and may decrease the risk of acute radiation toxicity as compared to SRT.

Is internal mammary nodes irradiation as a part of breast cancer postoperative radiotherapy necessary?

Postoperative radiotherapy plays an important role in the multidisciplinary treatment of breast cancer. However, it remains a controversy whether it is necessary to carry out prophylactic internal mammary nodes irradiation (IMNI). This review will focus on this topic. In our opinion, the total risk of relapse should be considered during the decision-making on IMNI; in particular, IMNI is recommended for high-risk patients whose tumor is located at the central/medial area or in patients with positive axillary lymph nodes.

Less increase of CT-based calcium scores of the coronary arteries : Effect three years after breast-conserving radiotherapy using breath-hold

PURPOSE

The aim of this prospective longitudinal study was to compare coronary artery calcium (CAC) scores determined before the start of whole breast irradiation with those determined 3 years afterwards.

PATIENTS AND METHODS

Changes in CAC scores were analysed in 99 breast cancer patients. Three groups were compared: patients receiving left- and right-sided radiotherapy, and those receiving left-sided radiotherapy with breath-hold. We analysed overall CAC scores and left anterior descending (LAD) and right coronary artery (RCA) CAC scores. Between the three groups, changes of the value of the LAD minus the RCA CAC scores of each individual patient were also compared.

RESULTS

Three years after breath-hold-based whole breast irradiation, a less pronounced increase of CAC scores was noted. Furthermore, LAD minus RCA scores in patients treated for left-sided breast cancer without breath-hold were higher when compared to LAD minus RCA scores of patients with right-sided breast cancers and those with left-sided breast cancer treated with breath-hold.

CONCLUSION

Breath-hold in breast-conserving radiotherapy leads to a less pronounced increase of CT-based CAC scores. Therefore, breath-hold probably prevents the development of radiation-induced coronary artery disease. However, the sample size of this study is limited and the follow-up period relatively short.