Postoperative radiotherapy in high-risk premenopausal women with breast cancer who receive adjuvant chemotherapy. Danish Breast Cancer Cooperative Group 82b Trial

Hypofractionated vs Conventionally Fractionated Postmastectomy Radiation After Implant-Based Reconstruction: A Randomized Clinical Trial

Importance

Postmastectomy radiation therapy (PMRT) improves local-regional disease control and patient survival. Hypofractionation (HF) regimens have comparable efficacy and complication rates with improved quality of life compared with conventional fractionation (CF) schedules. However, the use of HF after mastectomy in patients undergoing breast reconstruction has not been prospectively examined.

Objective

To compare HF and CF PMRT outcomes after implant-based reconstruction.

Design, Setting, and Participants

This randomized clinical trial assessed patients 18 years or older undergoing mastectomy and immediate expander or implant reconstruction for breast cancer (Tis, TX, or T1-3) and unilateral PMRT from March 8, 2018, to November 3, 2021 (median [range] follow-up, 40.4 [15.4-63.0] months), at 16 US cancer centers or hospitals. Analyses were conducted between September and December 2023.

Interventions

Patients were randomized 1:1 to HF or CF PMRT. Chest wall doses were 4256 cGy for 16 fractions for HF and 5000 cGy for 25 fractions for CF. Chest wall toxic effects were defined as a grade 3 or higher adverse event.

Main Outcomes and Measures

The primary outcome was the change in physical well-being (PWB) domain of the Functional Assessment of Cancer Therapy-Breast (FACT-B) quality-of-life assessment tool at 6 months after starting PMRT, controlling for age. Secondary outcomes included toxic effects and cancer recurrence.

Results

Of 400 women (201 in the CF arm and 199 in the HF arm; median [range] age, 47 [23-79] years), 330 patients had PWB scores at baseline and at 6 months. There was no difference in the change in PWB between the study arms (estimate, 0.13; 95% CI, -0.86 to 1.11; P = .80), but there was a significant interaction between age group and study arm (P = .03 for interaction). Patients younger than 45 years had higher 6-month absolute PWB scores if treated with HF rather than CF regimens (23.6 [95% CI, 22.7-24.6] vs 22.0 [95% CI, 20.7-23.3]; P = .047) and reported being less bothered by adverse effects (mean [SD], 3.0 [0.9] in the HF arm and 2.6 [1.2] in the CF arm; P = .02) or nausea (mean [SD], 3.8 [0.4] in the HF arm and 3.6 [0.8] in the CF arm; P = .04). In the as-treated cohort, there were 23 distant (11 in the HF arm and 12 in the CF arm) and 2 local-regional (1 in the HF arm and 1 in the CF arm) recurrences. Chest wall toxic effects occurred in 39 patients (20 in the HF arm and 19 in the CF arm) at a median (IQR) of 7.2 (1.8-12.9) months. Fractionation was not associated with chest wall toxic effects on multivariate analysis (HF arm: hazard ratio, 1.02; 95% CI, 0.52-2.00; P = .95). Fewer patients undergoing HF vs CF regimens had a treatment break (5 [2.7%] vs 15 [7.7%]; P = .03) or required unpaid time off from work (17 [8.5%] vs 34 [16.9%]; P = .02).

Conclusions and Relevance

In this randomized clinical trial, the HF regimen did not significantly improve change in PWB compared with the CF regimen. These data add to the increasing experience with HF PMRT in patients with implant-based reconstruction.

Trial Registration

ClinicalTrials.gov Identifier: NCT03422003.

RecurIndex-Guided postoperative radiotherapy with or without Avoidance of Irradiation of regional Nodes in 1-3 node-positive breast cancer (RIGAIN): a study protocol for a multicentre, open-label, randomised controlled prospective, phase III trial

INTRODUCTION

Postoperative radiotherapy in patients with breast cancer with one to three lymph node metastases, particularly within the pT1-2N1M0 cohort with a low clinical risk of local-regional recurrence (LRR), has incited a discourse surrounding personalised treatment strategies. Multigene testing for Recurrence Index (RecurIndex) model capably differentiates patients based on their level of LRR risk. This research aims to validate whether a more aggressive treatment approach can enhance clinical outcomes in N1 patients who possess a clinically low risk of LRR, yet a high RecurIndex-determined risk of LRR. Specifically, this entails postoperative whole breast irradiation combined with regional lymph node irradiation (RNI) following breast-conserving surgery or chest wall irradiation with RNI after mastectomy.

METHODS AND ANALYSIS

The RIGAIN (RecurIndex-Guided postoperative radiotherapy with or without Avoidance of Irradiation of regional Nodes in 1-3 node-positive breast cancer) Study is a multicentre, prospective, randomised, open-label, phase III clinical trial that is being conducted in China. In this study, patients with low clinical LRR risk but high RecurIndex-LRR risk are randomly assigned in a 1:1 ratio to the experimental group or the control group. In the experimental group, RNI is performed and the control group omits RNI. Efficacy and safety analyses will be conducted, enrolling a total of 540 patients (270 per group). The primary endpoint is invasive disease-free survival, and secondary endpoints include any first recurrence, LRR-free survival, distant metastasis-free survival, recurrence-free survival, overall survival, disease-free survival, breast cancer-specific mortality and assessment of patient quality of life. The study began in April 2023 and with a follow-up period of 60 months after the last participant completes radiation therapy.

ETHICS AND DISSEMINATION

The study was approved by the Ethics Committee of Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University (SYSKY-2022-097-02, V.3.1). It adheres to the Helsinki Declaration and Good Clinical Practice. Research findings will be submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04069884.

Post-Operative Radiation in Early Breast Cancer with N1 Disease: 10-Year Follow-Up

Post-operative radiotherapy for post-menopausal women with early breast cancer and N1 disease is controversial. Although locoregional control is improved, overall survival (OS) benefit is unclear. The clinical benefit of post-operative irradiation in this group of patients over 10 years was reviewed. We aimed to evaluate the OS, disease-free survival (DFS), and factors affecting OS and DFS. A retrospective review of 191 post-menopausal women with early breast cancer and N1 disease from 2004 to 2011 was performed. Demographics, post-operative histology, adjuvant treatment, OS, and DFS were evaluated. Post-operative radiation was given to 95 of 191 women (49.7%). Younger age at diagnosis (p < 0.001), a greater number of involved nodes (p = 0.004), lymphovascular invasion (LVI), and a higher tumor grade (p = 0.001) were more likely in women who received post-operative radiation. Nodal radiation did not improve 10-year DFS (p = 0.084) or OS (p = 0.203). Post-operative nodal radiation was associated with significant improvement in 10-year OS in women who received only hormonal therapy (p = 0.047) and no other systemic therapy. Women with unfavorable risk factors were more likely to receive post-operative radiation, likely due to a perceived higher risk of recurrence. Nodal radiation did not significantly improve 10-year DFS or OS in early breast cancer patients with N1 disease, and the benefit was not clearly demonstrated. However, in those who were on hormonal therapy, radiotherapy was beneficial in improving overall survival.

Assessment of Postmastectomy Radiation Therapy Receipt by Age and Association With Outcomes in Women With Breast Cancer

PURPOSE

Postmastectomy radiation therapy (PMRT) reduces locoregional recurrence (LRR) and improves overall survival (OS) in patients with breast cancer. Young age has been recognized as a risk factor for LRR. The primary objective of this study was to determine if recommendations for PMRT differed among patients younger than 50 years as compared to women aged 50 years or older.

METHODS

We reviewed medical records of patients with breast cancer who underwent mastectomy with or without PMRT from 2010 through 2018. Univariable and multivariable models were used to estimate the association of age with PMRT.

RESULTS

Of 2471 patients, 839 (34%) were <50 years; 1632 (66%) were ≥50 years. Patients <50 years had a higher percentage of grade 3 tumors, hormone receptor (HR) negative and/or Her-2/neu positive tumors, clinical stage T2/T3 tumors, and nodal involvement. Compared with patients ≥50 years, patients <50 years were more likely to undergo PMRT (OR 1.57; P = .001) and regional node irradiation (RNI) to the internal mammary nodes. Advanced clinical and pathologic stage, invasive tumor histology, the presence of lymphovascular invasion, and treatment with systemic chemotherapy were predictors of PMRT receipt for patients <50 years (P < .05). PMRT was associated with improved OS and recurrence free survival (RFS) among all patients (P < .01).

CONCLUSION

Patients <50 years were more likely to undergo PMRT and to receive RNI to the internal mammary nodes but were also more likely to have other risk factors for recurrence that would warrant a PMRT recommendation. PMRT improved OS and RFS for all patients.

The Challenges of Lobular Carcinomas from a Surgeon's Point of View

Invasive lobular breast cancer (ILC) presents unique challenges and considerations in the realm of surgical management. Characterized by its distinct histological features, including the loss of E-cadherin expression and dys-cohesive growth pattern, ILC often poses diagnostic and therapeutic dilemmas for clinicians. This abstract explores the surgical landscape of ILC, focusing on its epidemiology, clinical presentation, diagnostic modalities, and surgical interventions. Emphasizing the importance of individualized treatment strategies, this narrative delves into the nuances of surgical decision-making, including the role of breast-conserving surgery versus mastectomy, axillary staging, and the significance of margin status. Additionally, advancements in surgical techniques, such as oncoplastic approaches and sentinel lymph node biopsy, are examined in the context of optimizing oncologic outcomes and preserving cosmesis. Through a comprehensive review of current literature and clinical guidelines, this overview aims to provide a nuanced understanding of the surgical considerations inherent to the management of invasive lobular breast cancer.

Skin perfusion and oxygen saturation after mastectomy and radiation therapy in breast cancer patients

The pathophysiological mechanism behind complications associated with postmastectomy radiotherapy (PMRT) and subsequent implant-based breast reconstruction are not completely understood. The aim of this study was to examine if there is a relationship between PMRT and microvascular perfusion and saturation in the skin after mastectomy and assess if there is impaired responsiveness to a topically applied vasodilator (Methyl nicotinate - MN). Skin microvascular perfusion and oxygenation >2 years after PMRT were measured using white light diffuse reflectance spectroscopy (DRS) and laser Doppler flowmetry (LDF) in the irradiated chest wall of 31 women with the contralateral breast as a control. In the non-irradiated breast, the perfusion after application of MN (median 0.84, 25th-75th centile 0.59-1.02 % RBC × mm/s) was higher compared to the irradiated chest wall (median 0.51, 25th-75th centile 0.21-0.68 % RBC × mm/s, p < 0.001). The same phenomenon was noted for saturation (median 91 %, 25th-75th centile 89-94 % compared to 89 % 25th-75th centile 77-93 %, p = 0.001). Eight of the women (26%) had a ≥10 % difference in skin oxygenation between the non-irradiated breast and the irradiated chest wall. These results indicate that late microvascular changes caused by radiotherapy of the chest wall significantly affect skin perfusion and oxygenation.

Anatomical assessment of local recurrence site in breast cancer patients after breast reconstruction and post-mastectomy radiotherapy: implications for radiation volumes and techniques

INTRODUCTION

Post-mastectomy radiotherapy (PMRT) improves local control rates and survival in patients with adverse prognostic features. The dose coverage to target volumes is critical to yield maximum benefit to treated patients, increasing local control and reducing risk of toxicity. This study aims to assess patterns of breast cancer relapse in patients treated with mastectomy, breast reconstruction and PMRT.

METHODS

Breast cancer patients treated with PMRT between 1992 and 2017 were retrospectively reviewed. Clinical and pathological characteristics of patients were collected. Recurrences were defined as "in field," "marginal" or "out of field." Survival analyses were performed in relation to progression-free survival (PFS) and overall survival (OS). Correlation between baseline features was explored.

RESULTS

Data of 140 patients are collected. After a median follow-up time of 72 months, median PFS and OS of 63 and 74 months were detected, respectively. Neoadjuvant chemotherapy, lympho-vascular space invasion (LVI) and size of primary tumor were all significantly associated with worst PFS and OS. Ten patients developed local recurrence: 30% "in field," 30% marginal recurrences, 20% "out of field" and 20% both "in field" and "out of field." No recurrence was detected under the expander, 80% above the device and 20% patients relapsed on IMN chain. The mean distant relapse-free survival was 39 months. Overall, 39 of 140 patients developed distant metastases.

CONCLUSIONS

The onset of local-regional relapses occurred mainly above the expander/prosthesis, underlying the importance of inclusion of the subcutaneous tissues within the target volume. In order to refine new contouring recommendations for PMRT and breast reconstruction, future prospective studies are needed.

The impact of bolus on clinical outcomes for post-mastectomy breast cancer patients treated with IMRT: data from China

PURPOSE

This study aims to investigate the effects of chest wall bolus in intensity-modulated radiotherapy (IMRT) technology on clinical outcomes for post-mastectomy breast cancer patients.

MATERIALS AND METHODS

This retrospective study included patients with invasive carcinoma ((y)pT0-4, (y)pN0-3) who received photon IMRT after mastectomy at the Affiliated Hospital of Qingdao University from 2014 to 2019. The patients were divided into two groups based on whether they received daily bolus application or not, and the baseline characteristics were matched using propensity score matching (PSM). Cumulative incidence (CI) of local recurrence (LR), locoregional recurrence (LRR), overall survival (OS) and disease-free survival (DFS) were evaluated with a log-rank test. Acute skin toxicity and late radiation pneumonia was analyzed using chi-square test.

RESULTS

A total of 529 patients were included in this study, among whom 254 (48%) patients received bolus application. The median follow-up time was 60 months. After matching, 175 well-paired patients were selected. The adjusted 5-year outcomes (95% confidence interval) in patients treated with and without bolus were, respectively: CI of LR 2.42% (0.04-4.74) versus 2.38% (0.05-4.65), CI of LRR 2.42% (0.04-4.74) versus 3.59% (0.73-6.37), DFS 88.12% (83.35-93.18) versus 84.69% (79.42-90.30), OS 94.21% (90.79-97.76) versus 95.86% (92.91-98.91). No correlation between bolus application and skin toxicity (P = 0.555) and late pneumonia (P = 0.333) was observed.

CONCLUSIONS

The study revealed a low recurrence rate using IMRT technology. The daily used 5 mm chest wall bolus was not associated with improved clinical outcomes.

The impact of the new ESTRO-ACROP target volume delineation guidelines for postmastectomy radiotherapy after implant-based breast reconstruction on breast complications

The European Society for Radiotherapy and Oncology-Advisory Committee in Radiation Oncology Practice (ESTRO-ACROP) updated a new target volume delineation guideline for postmastectomy radiotherapy (PMRT) after implant-based reconstruction. This study aimed to evaluate the impact on breast complications with the new guideline compared to the conventional guidelines. In total, 308 patients who underwent PMRT after tissue expander or permanent implant insertion from 2016 to 2021 were included; 184 received PMRT by the new ESTRO-ACROP target delineation (ESTRO-T), and 124 by conventional target delineation (CONV-T). The endpoints were major breast complications (infection, necrosis, dehiscence, capsular contracture, animation deformity, and rupture) requiring re-operation or re-hospitalization and any grade ≥2 breast complications. With a median follow-up of 36.4 months, the cumulative incidence rates of major breast complications at 1, 2, and 3 years were 6.6%, 10.3%, and 12.6% in the ESTRO-T group, and 9.7%, 15.4%, and 16.3% in the CONV-T group; it did not show a significant difference between the groups (p = 0.56). In multivariable analyses, target delineation is not associated with the major complications (sHR = 0.87; p = 0.77). There was no significant difference in any breast complications (3-year incidence, 18.9% vs. 23.3%, respectively; p = 0.56). Symptomatic RT-induced pneumonitis was developed in six (3.2%) and three (2.4%) patients, respectively. One local recurrence occurred in the ESTRO-T group, which was within the ESTRO-target volume. The new ESTRO-ACROP target volume guideline did not demonstrate significant differences in major or any breast complications, although it showed a tendency of reduced complication risks. As the dosimetric benefits of normal organs and comparable oncologic outcomes have been reported, further analyses with long-term follow-up are necessary to evaluate whether it could be connected to better clinical outcomes.

Magnetic resonance imaging findings of radiation-induced breast angiosarcoma: A case report

BACKGROUND

Breast conservation surgery (BCS) with adjuvant radiotherapy has become a gold standard in the treatment of early-stage breast cancer, significantly reducing the risk of tumor recurrence. However, this treatment is associated with adverse effects, including the rare but aggressive radiation-induced angiosarcoma (RIAS). Despite its rarity and nonspecific initial presentation, RIAS presents a challenging diagnosis, emphasizing the importance of imaging techniques for early detection and accurate diagnosis.

CASE SUMMARY

We present a case of a 48-year-old post-menopausal woman who developed skin ecchymosis on the right breast seven years after receiving BCS and adjuvant radiotherapy for breast cancer. Initial mammography and ultrasound were inconclusive, showing post-treatment changes but failing to identify the underlying angiosarcoma. Contrast-enhanced breast magnetic resonance imaging (MRI) revealed diffuse skin thickening and nodularity with distinctive enhancement kinetics, leading to the diagnosis of RIAS. This case highlights the crucial role of MRI in diagnosing and determining the extent of RIAS, facilitating timely and appropriate surgical intervention.

CONCLUSION

Breast MRI is crucial for detecting RIAS, especially when mammography and ultrasound are inconclusive.

The Impact of Timing of Delayed Autologous Breast Reconstruction following Postmastectomy Radiation Therapy on Postoperative Morbidity

BACKGROUND

 The ideal time to perform reconstruction after the completion of postmastectomy radiation therapy (PMRT) in patients with locally advanced breast cancer is currently unknown. We evaluate the association between the timing of delayed autologous breast reconstruction following PMRT and postoperative complications.

METHODS

 Patients who underwent mastectomy, PMRT, and then delayed autologous breast reconstruction from 2009 to 2016 were identified from the Truven Health MarketScan Research Databases. Timing of reconstruction following PMRT was grouped 0-3, 3-6, 6-12, 12-24, and after 24 months. Multivariable models were used to assess associations between timing of reconstruction following PMRT and key measures of morbidity.

RESULTS

 A total of 1,039 patients met inclusion criteria. The rate of any complications for the analytic cohort was 39.4%, including 13.3% of patients who experienced wound complications and 11.3% of patients requiring additional flaps. Unadjusted rates of complications increased from 23.4% between 0 and 3 months to 49.4% between 3 and 6 months and decreased thereafter. Need for additional flaps was highest within 3 to 6 months (14.0%). Multivariate analysis revealed higher rates of any complications when reconstruction was performed between 3 and 6 months (odds ratio [OR]: 3.04, p < 0.001), 6 and 12 months (OR: 2.66, p < 0.001), or 12 and 24 months (OR: 2.13, p = 0.001) after PMRT. No difference in complications were noted in reconstructions performed after 24 months compared with those performed before 3 months (p > 0.05). However, rates of wound complications were least likely in reconstructions after 24 months (OR: 0.34, p = 0.035).

CONCLUSION

 These findings suggest plastic surgeons may consider performing autologous breast reconstruction early for select patients, before 3 months following PMRT without increasing postoperative morbidity.

Predicting the Survival Benefit of Radiotherapy in Elderly Breast Cancer Patients: A Population-Based Analysis

INTRODUCTION

This study aimed to establish two prediction tools predicting cancer-specific survival (CSS) and overall survival (OS) in elderly breast cancer patients with or without radiotherapy.

METHODS

Clinicopathological data of breast cancer patients aged more than 70 y from 2010 to 2018 were retrospectively collected from the Surveillance, Epidemiology, and End Results database. Patients were randomly divided into the training and validation cohorts at 7:3, and the Cox proportional risk model was used to construct the nomograms. The concordance index, the area under the receiver operating characteristic curve, and the calibration plot are used to evaluate the discrimination and accuracy of the nomograms.

RESULTS

One lakh twenty eight thousand two hundred twenty three elderly breast cancer patients were enrolled, including 57,915 who received radiotherapy. The Cox regression model was used to identify independent factors. These independent influencing factors are used to construct the prediction models. The calibration plots reflect the excellent consistency between the predicted and actual survival rates. The concordance index of nomograms for CSS and OS was more than 0.7 in both the radiotherapy group and the nonradiotherapy group, and similar results are also shown in area under the receiver operating characteristic curve. Decision curve analysis showed that the prognostication accuracy of the model was much higher than that of the traditional tumor, node, metastasis staging.

CONCLUSIONS

Radiotherapy can benefit elderly breast cancer patients significantly. The two prediction tools provide a personalized survival scale for evaluating the CSS and OS of elderly breast cancer patients, which can better provide clinicians with better-individualized management for these patients.

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.

Is FAST FORWARD the Way Forward in Radiotherapy for Locally Advanced Breast Cancer - Learnings From the COVID Pandemic

INTRODUCTION

Low middle-income countries (LMICs), including India, have paucity of external beam radiotherapy (RT) machines leading to prolonged wait times for RT. Delay in delivery of RT has been shown to adversely affect outcomes in locally advanced breast cancer (LABC). With the availability of results of multiple randomized controlled trials, hypofractionated RT delivered over 3 to 4 weeks became the standard of care in breast cancer RT.

METHODS

We conducted a retrospective audit of 172 LABC patients treated with ultrahypofractionated adjuvant RT (radiotherapy completed in 1 week) during the COVID pandemic. Log rank and Cox-regression model used for univariate and multi-variate analyses.

RESULTS

No patient developed grade 3 esophagitis. Grade 2 esophagitis requiring short term narcotic analgesics was seen in 12 (6.9%) patients. Grade 2 or higher toxicity peaked between 2 and 3 weeks after RT. The estimated 2 and 3- year recurrence free survival (RFS) for the cohort is 87.1 % and 81.4 %, respectively. The estimated 2 and 3-year overall survival for the cohort is 95% and 91.3%. On multivariate analysis, presence of extra-nodal extension was found to be an independent factor associated with worse RFS (P = .028).

CONCLUSIONS

FAST FORWARD protocol RT in LABC appears well tolerated.

Radiotherapy for breast cancer

In early breast cancer, adjuvant moderately hypofractionated regimens are recommended for both whole breast, partial breast and locoregional irradiation which abbreviates the overall treatment time, as argued in this review. Gating is recommended as well as the use of a simultaneous integrated boost when indicated. A tangential field set-up is standard, however, for challenging cases volumetric modulated arc therapy techniques, or referral for proton therapy, may be considered. In the metastatic setting, stereotactic radiotherapy is a promising treatment option for oligometastatic disease.

Breast Reconstruction Complications After Postmastectomy Proton Radiation Therapy for Breast Cancer

Purpose

Our purpose was to report complications requiring surgical intervention among patients treated with postmastectomy proton radiation therapy (PMPRT) for breast cancer in the setting of breast reconstruction (BR).

Methods and Materials

Patients enrolled on a prospective proton registry who underwent BR with immediate autologous flap, tissue expander (TE), or implant in place during PMPRT (50/50.4 Gy +/- chest wall boost) were eligible. Major reconstruction complication (MRC) was defined as a complication requiring surgical intervention. Absolute reconstruction failure was an MRC requiring surgical removal of BR. A routine revision (RR) was a plastic surgery refining cosmesis of the BR. Kaplan-Meier method was used to assess disease outcomes and MRC. Cox regression was used to assess predictors of MRC.

Results

Seventy-three courses of PMPRT were delivered to 68 women with BR between 2013 and 2021. Median follow-up was 42.1 months. Median age was 47 years. Fifty-six (76.7%) courses used pencil beam scanning PMPRT. Of 73 BR, 29 were flaps (39.7%), 30 implants (41.1%), and 14 TE (19.2%) at time of irradiation. There were 20 (27.4%) RR. There were 9 (12.3%) MRC among 5 implants, 2 flaps, and 2 TE, occurring a median of 29 months from PMPRT start. Three-year freedom from MRC was 86.9%. Three (4.1%) of the MRC were absolute reconstruction failure. Complications leading to MRC included capsular contracture in 5, fat necrosis in 2, and infection in 2. On univariable analysis, BR type, boost, proton technique, age, and smoking status were not associated with MRC, whereas higher body mass index trended toward significance (hazard ratio, 1.07; 95% CI, 0.99-1.16; P = .10).

Conclusions

Patients undergoing PMPRT to BR had a 12.3% incidence of major complications leading to surgical intervention, and total loss of BR was rare. MRC rates were similar among reconstruction types. Minor surgery for RR is common in our practice.

Nomogram-Based Risk Stratification to Identify Patients with T3N0M0 Breast Cancer with Survival Benefit from Postmastectomy Radiotherapy

BACKGROUND

The survival benefit of postmastectomy radiotherapy (PMRT) for patients with T3N0M0 breast cancer remains controversial. This study aimed to identify patients with a survival benefit from PMRT by developing a novel risk stratification model.

PATIENTS AND METHODS

The study recruited 2062 patients with pT3N0M0 breast cancer from the Surveillance, Epidemiology, and End Results (SEER) database who underwent mastectomy between 2010 and 2019. Overall survival (OS) and breast-cancer-specific survival (BCSS) prognostic nomograms based on multivariate Cox regression were constructed to quantify the survival risk and classify patients into low- and high-risk groups. Subgroup analyses were undertaken to assess the role of PMRT according to age and risk stratification.

RESULTS

In the overall cohort, PMRT was beneficial in improving OS in patients with pT3N0 breast cancer (5-year OS, non-PMRT versus PMRT: 76.6% vs. 84.2%, P < 0.001), while the benefit on BCSS was not significant (P = 0.084). On the basis of the risk stratification nomogram, in the high-risk group, PMRT improved OS in young patients by 10.1%, OS in elderly patients by 12.4%, and BCSS by 10.2% (P < 0.05), but the use of PMRT in the low-risk group did not improve OS and BCSS in all patients (P > 0.05).

CONCLUSIONS

We presented a new method for quantifying risk using the nomogram to identify patients with high risk of pT3N0M0 breast cancer. This study found that older patients in the newly constructed high-risk group benefited from OS and BCSS benefits from PMRT, while for younger high-risk patients, there was only a benefit in terms of OS.

Estimating the risk and benefit of radiation therapy in (y)pN1 stage breast cancer patients: A Bayesian network model incorporating expert knowledge (KROG 22-13)

BACKGROUND

We aimed to evaluate the risk and benefit of (y)pN1 breast cancer patients in a Bayesian network model.

METHOD

We developed a Bayesian network (BN) model comprising three parts: pretreatment, intervention, and risk/benefit. The pretreatment part consisted of clinical information from a tertiary medical center. The intervention part regarded the field of radiotherapy. The risk/benefit component encompasses radiotherapy (RT)-related side effects and effectiveness, including factors such as recurrence, cardiac toxicity, lymphedema, and radiation pneumonitis. These factors were evaluated in terms of disability weights and probabilities from a nationwide expert survey. The overall disease burden (ODB) was calculated as the sum of the probability multiplied by the disability weight. A higher value of ODB indicates a greater disease burden for the patient.

RESULTS

Among the 58 participants, a BN model utilizing discretization and clustering techniques revealed five distinct clusters. Overall, factors associated with breast reconstruction and RT exhibited high discrepancies (24-34 %), while RT-related side effects demonstrated low discrepancies (3-11 %) among the experts. When incorporating recurrence and RT-related side effects, the mean ODB of (y)pN1 patients was 0.258 (range, 0.244-0.337), with a higher tendency observed in triple-negative breast cancer (TNBC) or mastectomy cases. The ODB for TNBC patients undergoing mastectomy without postmastectomy radiotherapy was 0.327, whereas for non-TNBC patients undergoing breast conserving surgery with RT, the disease burden was 0.251. There was an increasing trend in ODB as the field of RT increased.

CONCLUSION

We developed a Bayesian network model based on an expert survey, which helps to understand treatment patterns and enables precise estimations of RT-related risk and benefit in (y)pN1 patients.

Tolerance of Concurrent Adjuvant Radiation Therapy and Pembrolizumab for Triple Negative Breast Cancer: Real Life Experience

Purpose

The current standard-of-care management of locally advanced triple negative breast cancer (TNBC) is based on neoadjuvant chemo-immunotherapy with pembrolizumab, surgery, radiation therapy (RT), and adjuvant pembrolizumab. However, the safety of combining pembrolizumab with adjuvant breast RT has never been evaluated. This study evaluated the tolerance profile of concurrent pembrolizumab with adjuvant RT in patients with locally advanced TNBC.

Methods and Materials

This bicentric ambispective study included all the patients with early and locally advanced TNBC who received neoadjuvant chemo-immunotherapy with pembrolizumab and adjuvant RT as part of their treatment. The tolerance profile of adjuvant RT was evaluated and compared in patients who received concurrent pembrolizumab and in patients for whom pembrolizumab was withheld.

Results

Fifty-five patients were included between July 2021 and March 2023. Twenty-eight patients received adjuvant RT with concurrent pembrolizumab (RT+P group), and 27 patients had pembrolizumab withheld while receiving adjuvant RT (RT-only group). Two patients developed grade ≥3 toxicity (1 grade 3 pain in the RT+P group and 1 grade 3 radiodermatitis in the RT-only group), and there were no differences in terms of toxicity between the RT-only and the RT+P groups. No cardiac or pulmonary adverse event was reported during RT. With a median follow-up of 12 months (10-26), no patient relapsed.

Conclusions

In this study of limited size, the authors did not find a difference between the RT-only and RT+P groups in terms of toxicity. More studies and longer follow-up may add to the strength of this evidence.

Radiation therapy of the primary tumour and oligometastatic sites in patients with breast cancer with synchronous metastases: A literature review

De novo metastatic breast cancer represents 5 to 8% of all breast cancers (2500 new cases per year in France). Systemic treatment is the cornerstone of treatment, whereas radiation therapy usually has a palliative intent. Advances in systemic and local treatments (surgery and radiation therapy) have substantially improved overall survival. In the recent breast cancer statistics in the United States, the 5-year relative survival for patients diagnosed during 2012-2018 was 29% for stage IV (Breast Cancer Statistics). Thus, an increasing proportion of metastatic breast cancers present a prolonged complete response to systemic therapy, which raises the question of the impact of local treatment on patient survival. Radiation therapy has shown its value for early breast cancer, but its place in the local management of the primary tumour or oligometastatic sites for de novo metastatic breast cancer remains under debate. This article is a literature review assessing the role of radiation therapy directed to the primary tumour and oligometastatic sites of breast cancer in patients with synchronous metastases, in order to highlight clinicians in their therapeutic decision.

Quality of Life Outcomes and Determining Factors in Breast Cancer Patients Reporting to a Tertiary Care Centre in the Sub-Himalayan Region of India

PURPOSE

Breast cancer is the most common malignancy among women worldwide. This study was conducted to determine the quality of life (QOL) outcomes among breast cancer patients in the sub-Himalayan region and, secondly, to identify factors affecting them.

METHOD

The European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and BR-45 questionnaires in English and Hindi translations were used. The BR-45 Hindi translation was obtained using the forward-backward translation method. To check internal consistency and validity, Cronbach's alpha was employed. EORTC scoring manuals were used to score the questionnaires. The analysis of variance test was used to determine the impact of different treatment and sociodemographic factors on QOL domains.

RESULTS

The English and Hindi translations had Cronbach's alpha values of 0.949 and 0.950, respectively, suggesting that the data gathered were reliable. The mean score for global health status was 64.4 ± 29.7, the functional scale (FS) of QLQ_C30 was 76.9 ± 21.5, the FS of BR45 was 64.6 ± 24.1, the symptom scale (SS) of QLQ_C30 was 20.3 ± 19.2, and the SS of BR45 was 22.5 ± 19.1. Factors adversely affecting global health status included younger age, pre/perimenopausal status, and ongoing chemotherapy. Functional scales were significantly affected by marital status and earlier stages of the disease. Symptom scales were adversely affected by ongoing chemotherapy, an earlier stage of the disease, and a duration of treatment of less than six months.

CONCLUSION

Tailoring treatment to reduce radiotherapy, surgery, and systemic therapy-related side effects may improve QOL. Counselling and social support groups may help patients cope with the burden of family and societal roles.

The impact of post-mastectomy radiation timing on overall outcomes of autologous free-flap breast reconstruction

BACKGROUND

The optimal timing of post-mastectomy radiation therapy (PMRT) in autologous breast reconstruction is controversial. Our study compares overall reconstructive outcomes in patients who received post-mastectomy radiation therapy either before or after the autologous flap.

METHODS

A single-center retrospective review was performed for patients who underwent free flap breast reconstruction and post-mastectomy radiation from January 2004 through January 2021. Demographic, intraoperative, and post-operative variables were recorded.

RESULTS

A total of 452 free flaps were identified, and 82 underwent PMRT. 59.8% were radiated with an expander prior to free flap surgery (PreFlap), and 40.2% flaps underwent PMRT (PostFlap). PostFlap patients were significantly younger (43.0 vs. 47.9 years, p = .016). There were no significant differences in free flap outcomes between the two cohorts including thrombosis, venous congestion, flap loss, takebacks, fat necrosis, seroma, or infection. Mastectomy skin flap necrosis was significantly higher in the PostFlap cohort (9.1% vs. 0%, p = .032), but nipple necrosis rates did not differ. There were no significant differences in number or need for revision surgeries, fat necrosis, or fat grafting between groups. However, there were significantly more total reconstructive complications, including infection and wound breakdown, experienced by the PreFlap cohort (46.9% vs. 24.2%, p = .038).

CONCLUSIONS

Timing of PMRT did not impact free flap outcomes, but those who had the expander radiated experienced significantly more complications overall. For the 34.7% of patients in the preFlap group who planned for autologous reconstruction form initial consultation, radiation after the flap may have improved their overall outcomes. As added complications cause delays in cancer therapy and final reconstruction, our results suggest that PMRT of the flap when possible may improve the overall experience for breast cancer patients.

Outcomes with and without postmastectomy radiotherapy for pT3N0-1M0 breast cancer: An institutional experience

AIM

The objective of this study is to comprehensively evaluate the therapeutic efficacy of postmastectomy radiotherapy (PMRT) in treating patients with pT3N0-1M0 breast cancer within the context of modern therapeutic strategies.

METHODS

Clinical data from patients with pT3N0-1M0 breast cancer who underwent mastectomy from January 2005 to December 2018 at our institution were retrospectively analyzed.

RESULTS

The study involved a total of 222 participants, with 112 individuals undergoing PMRT and 110 individuals not receiving it. The median follow-up duration was 77 months (range: 6-171 months). The entire cohort demonstrated 5-year disease-free survival (DFS) and overall survival (OS) rates of 85.1% and 91.0%, respectively, along with a locoregional recurrence (LRR) rate as low as 7.2%. The PMRT group showed significantly better 5-year DFS (90.2% vs. 80.0%, p = 0.02) and OS (95.5% vs. 86.4%, p = 0.012) rates, as well as a lower LRR rate (4.5% vs. 10.0%, p = 0.122), compared to the group without PMRT. Cox regression analysis confirmed the independent prognostic significance of PMRT for both DFS (p = 0.040) and OS (p = 0.047). Following propensity score matching (PSM), the analysis included 100 matched patients, revealing an improved prognosis for those who received PMRT (DFS: p = 0.067; OS: p = 0.043).

CONCLUSIONS

Our study reveals favorable prognoses for pT3N0-1M0 breast cancer patients treated within contemporary therapeutic approaches. The pivotal role of PMRT in this context is evident. However, due to the retrospective design of our study and the relatively limited sample size, further investigation is imperative to validate and enhance these initial findings.

Impact of breath hold on regional nodal irradiation and heart volume in field in left breast cancer adjuvant irradiation

PURPOSE

Compared to the free-breathing technique, adjuvant left breast irradiation after breast-conserving surgery or mastectomy using the breath-hold method significantly reduces the heart mean dose, Left anterior descending artery, and ipsilateral lung doses. Movement with deep inspiration may also reduce heart volume in the field and regional node doses.

MATERIALS AND METHODS

Pre-radiotherapy planning CT was performed in the free-breathing, and breath-hold techniques using RPM, demographic information, clinicopathological data, heart volume in the field, heart mean dose, LAD mean dose, and regional nodal doses were calculated in both free breathing and DIBH. Fifty patients with left breast cancer receiving left breast adjuvant radiation were enrolled.

RESULTS

There was no significant difference in axillary LN coverage between the two techniques, except for SCL maximum dose, Axilla I node maximum dose, and Axilla II minimum dose in favor of the breath hold technique. The mean age was 47.54 years, 78% had GII IDC, 66% had positive LVSI results, and 74% of patients had T2. The breath hold strategy resulted in considerably decreased mean heart dose (p = 0.000), LAD dose (p = 0.000), ipsilateral lung mean dose (p = 0.012), and heart volume if the field (p = 0.013). The mean cardiac dosage and the dose of the LAD were significantly correlated (p = 0.000, R = 0.673). Heart volume in the field and heart mean dosage was not significantly correlated (p = 0.285, r = - 0.108).

CONCLUSION

When compared to free breathing scans, DIBH procedures result in considerably reduced dosage to the OAR and no appreciable changes in dose exposure to regional lymph node stations in patients with left-sided breast cancer.

De-escalation of Post-mastectomy Irradiation in Hormone Receptor-Positive Breast Cancer with One to Three Positive Nodes

BACKGROUND

The 21-gene recurrence score (RS) is used to predict benefit from chemotherapy in hormone receptor (HR)-positive breast cancer with one to three positive lymph nodes. Prospective-retrospective studies have shown that the RS is prognostic for both systemic and locoregional recurrence in tamoxifen-treated patients. We aimed to assess whether RS could be utilized to predict a survival benefit from postmastectomy radiation therapy (PMRT).

PATIENTS AND METHODS

The National Cancer Database (NCDB) was used to identify women ≤ 75 years of age with HR+, HER2-negative, T1-3, N1, M0 breast cancer who underwent mastectomy and axillary staging with available RS during the years 2010-2016. Kaplan-Meier and Cox proportional hazards models were used to identify association between treatment and overall survival (OS). Univariate and multivariate analyses were used to identify variables correlating with PMRT and OS.

RESULTS

A total of 8907 patients were identified. Of the total, 3203 (36%) patients received adjuvant PMRT and 5704 (64%) did not. Across the entire cohort, 5-year OS was 97.5% for patients receiving PMRT and 96.8% for those who did not (P = 0.063). After adjusting for all covariates, in patients with RS ≤ 25, there was no statistically significant improvement in 5-year OS with the addition of adjuvant PMRT (97.5% versus 98.1% P = 0.093). Moreover, no survival benefit was seen with axillary node dissection (P = 0.58) or with the addition of chemotherapy (P = 0.312).

CONCLUSIONS

In our cohort of patients with one to three positive nodes and a RS ≤ 25, omission of post-mastectomy radiation therapy had no impact on OS. Our results suggest that RS may be utilized in the individualized decision making on PMRT.

To Dissect or Not to Dissect: Can We Predict the Presence of Four or More Axillary Lymph Node Metastases in Postmenopausal Women with Clinically Node-Negative Breast Cancer?

BACKGROUND

Axillary lymph node (ALN) involvement is important for prognosis and guidance of multidisciplinary treatment of breast cancer patients. This study sought to identify preoperative clinicopathologic factors predictive of four or more pathologically positive ALNs in patients with cN0 disease and to develop a predictive nomogram to inform therapy recommendations.

METHODS

Using an institutional prospective database, the study identified postmenopausal women with cN0 invasive breast cancer undergoing upfront sentinel lymph node biopsy (SLNB) with or without completion ALND (cALND) between 1993 and 2007. Logistic regression analyses identified factors predictive of four or more positive nodes in the cN0 population and patients with one, two, or more SLNs.

RESULTS

The study identified 2532 postmenopausal women, 615 (24.3%) of whom underwent cALND. In the univariate analysis, tumor size, lymphovascular (LVI), histology, estrogen receptor (ER)-positive status, and multifocality/multicentricity were predictive of four or more positive nodes (n = 63; p < 0.05), and all except ER status were significant in the multivariate analysis. Of the 2532 patients, 1263 (49.2%) had hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative disease, and 30 (2.4%) were found to have four or more positive nodes. Of the 130 patients with exactly one positive SLN who underwent cALND (n = 130, 5.4%), 7 had four or more positive nodes, with grade as the only predictive factor (p = 0.01). Of the 33 patients with two or more positive SLNs who underwent cALND, 9 (27.3%) had four or more positive nodes after cALND, but no factors were predictive in this subset.

CONCLUSION

Postmenopausal women with early-stage cN0 HR-positive, HER2-negative breast cancer with a single positive SLN had a very low risk (5%) of having four or more positive nodes on final pathology. With such a low risk of N2 disease, limited staging with SLNB may be sufficient to guide therapy decisions for this subset of patients.

Quality assurance in a phase III, multicenter, randomized trial of POstmastectomy radioThErapy in Node posiTive breast cancer with or without Internal mAmmary nodaL irradiation (POTENTIAL): a planning benchmark case

PURPOSE

To report the planning benchmark case results of the POTENTIAL trial-a multicenter, randomized, phase 3 trial-to evaluate the value of internal mammary nodal (IMN) irradiation for patients with high-risk breast cancer.

METHODS

All participating institutions were provided the outlines of one benchmark case, and they generated radiation therapy plans per protocol. The plans were evaluated by a quality assurance team, after which the institutions resubmitted their revised plans. The information on beams arrangement, skin flash, inhomogeneity corrections, and protocol compliance was assessed in the first and final submission.

RESULTS

The plans from 26 institutions were analyzed. Some major deviations were found in the first submission. The protocol compliance rates of dose coverage for the planning target volume of chest wall, supraclavicular fossa plus axilla, and IMN region (PTVim) were all significantly improved in the final submission, which were 96.2% vs. 69.2%, 100% vs. 76.9%, and 88.4% vs. 53.8%, respectively. For OARs, the compliance rates of heart Dmean, left anterior descending coronary artery V40Gy, ipsilateral lung V5Gy, and stomach V5Gy were significantly improved. In the first and final submission, the mean values of PTVim V100% were 79.9% vs. 92.7%; the mean values of heart Dmean were 11.5 Gy vs. 9.7 Gy for hypofractionated radiation therapy and 11.5 Gy vs. 11.0 Gy for conventional fractionated radiation therapy, respectively.

CONCLUSION

The major deviations were corrected and protocol compliance was significantly improved after revision, which highlighted the importance of planning benchmark case to guarantee the planning quality for multicenter trials.

De-escalated radiotherapy for HER2-overexpressing breast cancer patients with 1-3 positive lymph nodes undergoing anti-HER2 targeted therapy

Background

In the era of anti-HER2 targeted therapy, the potential clinical feasibility of considering HER2-overexpressing breast cancer cases presenting with 1-3 positive axillary lymph nodes as low-risk, and thereby contemplating postoperative radiotherapy reduction, remains an important subject for in-depth examination. The aim of this retrospective study was to evaluate the effectiveness of de-escalated radiotherapy in T1-2N1M0 HER2-overexpressing breast cancer patients receiving anti-HER2 targeted therapy. Specifically, omitting regional lymph node irradiation (RNI) after breast-conserving surgery and only performing whole-breast irradiation or omitting postmastectomy radiation therapy.

Methods

A retrospective analysis was conducted on 429 patients with stage T1-2N1M0 primary invasive HER2-overexpressing breast cancer from our center between 2004 and 2018. Patients who received anti-HER2 targeted therapy were divided into an RNI group and a no RNI group to assess the role of RNI. The prognostic role of RNI was investigated via the Kaplan-Meier method and Cox proportional hazards modeling.

Results

The median follow-up time was 46.8 months (range 7.1-225.8 months). In the anti-HER2 targeted therapy group RNI yielded no significant improvements in invasive disease-free survival (IDFS) (p = 0.940), local-regional recurrence-free survival (p = 0.380), distant metastases-free survival (p = 0.698), or overall survival (p = 0.403). Estrogen receptor (ER) status (hazard ratio [HR] 0.105, 95% confidence interval [CI] 0.023-0.749, p = 0.004) and lymph vascular invasion status (LVI) (HR 5.721, 95% CI 1.586-20.633, p = 0.008) were identified as independent prognostic factors for IDFS, and ER-positive and LVI-negative patients exhibited better prognoses.

Conclusion

Omitting RNI may be a safe option in T1-2N1 HER2-overexpressing breast cancer patients receiving standardized anti-HER2 targeted therapy; particularly in ER-positive or LVI-negative subgroups.

Near-Surface Dose Correlates With Moist Desquamation and Unplanned Reconstructive Surgery in Patients With Implant-Based Reconstruction Receiving Postmastectomy Radiation Therapy

Purpose

Postmastectomy radiation therapy (PMRT) reduces disease recurrence in appropriately selected patients but may compromise implant-based reconstruction. We investigated whether near-surface dose correlates with radiation-related toxic effects in these patients.

Methods and Materials

Patients receiving PMRT at a single institution from 2016 to 2019 were retrospectively reviewed. Patient demographics and treatment information were collected. Three near-surface structures were retrospectively generated, bound by the chest wall tangent beam as well as the skin surface and the skin-3 mm contour (SR3), skin surface and skin-5 mm contour (SR5), or skin-5 and skin-10 mm contours. Dosimetric analysis of these near-surface contours was performed in 2 Gy intervals. Univariate and multivariate analyses were used to identify predictors of moist desquamation, grade 2+ chest wall pain, use of opiate pain medication, unplanned reconstructive surgery, and implant failure. Logistic regression for each outcome and near-surface contour was performed for receiver-operator area under the curve (AUC) analysis and the Youden J Statistic was used to determine the optimal threshold for each dosimetric parameter.

Results

Of 126 patients reviewed, 109 met the study's eligibility criteria. Median follow-up was 2.3 years. Twenty-five patients (23%) underwent unplanned reconstructive surgery, and 10 (9.2%) experienced implant failure. Among clinical variables, low body mass index and history of smoking predicted unplanned surgery on univariate and multivariate analyses, and moist desquamation predicted grade 2+ chest wall pain. The top dosimetric parameters by AUC for moist desquamation, grade 2+ chest wall pain, use of opiates, unplanned reconstructive surgery, and implant failure were SR5 D10 cc (AUC = 0.701, optimal threshold 57.8 Gy, P < .001), SR3 D10 cc (AUC = 0.600, optimal threshold 56.8 Gy, P = .079), SR5 D10 cc (AUC = 0.642, optimal threshold 57.3 Gy, P = .041), SR3 V44 Gy (AUC = 0.711, optimal threshold 81%, P = .001), and SR3 V44 Gy (AUC = 0.688, optimal threshold 82%, P = .052), respectively.

Conclusions

Near-surface dose correlates with moist desquamation and unplanned reconstructive surgery after PMRT. Further evaluation of prospective optimization of dosimetric parameters related to SR3 and SR5 should be considered.

Effect of radiation therapy during surgery on postoperative wound complications after breast reconstruction in patients with breast cancer: A meta-analysis

Breast remodelling is a major therapeutic choice in radical mastectomy. Breast reconstruction is regarded as a promising option for the treatment of breast cancer. The purpose of this meta-analysis was to investigate the effect of Post mastectomy radiotherapy (PMRT) on postoperative wound complications in breast carcinoma. A comprehensive review of documents was conducted between the date of establishment and the 28th of August 2023. In all of the trials, patients were treated with breast cancer. The researchers chose 11 publications out of 8068 related studies. Two researchers examined these publications to satisfy the inclusion criteria. Among the 516 patients who had received radiation therapy in the course of the operation, 1772 had not received radiation therapy. The impact of radiation therapy and non-radiation therapy in breast cancer patients after breast reconstruction was reported in 8 studies, and the incidence of postoperative wound infection in non-radiation group was significantly lower (OR, 1.95; 95% CI, 1.26-3.02 p = 0.003). In nine studies, There is not considered to have achieved statistical significance between radiation therapy and non-radiation treatment for post-operation wound dehiscence in breast cancer patients who had received chemotherapy (OR, 1.61; 95% CI, 0.70-3.72 p = 0.27). The results of six trials demonstrated that radiation therapy and non-radiation therapy had no statistical significance on post-operation haemorrhage in breast cancer patients (OR, 1.02; 95% CI, 0.42-2.47 p = 0.96). The results of 7 trials demonstrated that radiation therapy and non-radiation therapy had no significant impact on the post-operation of skin necrosis (OR, 1.22; 95% CI, 0.66-2.28 p = 0.53). Two trials demonstrated that those without radiation therapy were less likely than those who received radiation therapy in skin contracture in patients (OR, 7.24; 95% CI, 1.80-29.10 p = 0.005). Regarding the incidence of wound infection and cutaneous contraction was higher in the radiation group.

The trade-off of post-mastectomy radiotherapy usage for the breast cancer patients aged 70 years or older: a study based on SEER database

BACKGROUND

This study aimed to investigate the role of post-mastectomy radiotherapy (PMRT) in the female aged 70 years or older diagnosed with breast cancer, which is still controversial.

METHODS

This retrospective study enrolled female breast cancer women aged 70 + years following mastectomy from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was performed to reduce covariable imbalance. A nomogram was created to predict the 1,3,5-years overall survival (OS) and divide patients into three risk groups.

RESULTS

After matching, PMRT were associated with significant improvement in breast cancer-specific survival (BCSS) and OS (p < 0.001). By contrast, the BCSS and OS benefit from PMRT were not significant in patients with T1N1 tumor (BCSS: HR = 0.716, p = 0.249;OS:HR = 0.908, p = 0.572), and T2N1 tumor (BCSS:HR = 0.866, p = 0.289;OS:HR = 0.879, p = 0.166). Stratified by subtype, the HR+/HER-2- subtype and the HR-/HER-2- subtype (all p < 0.001) have a significant prolonged survival, yet not significant BCSS difference are shown in the HER-2 + tumor. In the low-risk group as determined by the nomogram, the use of PMRT did not significantly improve OS (p = 0.203).

CONCLUSIONS

This study demonstrated that PMRT improves the survival of females with elderly breast cancer, while for T1-2N1 breast cancer patients, the omission of PMRT could be considered. Furthermore, the nomogram we constructed could be used as a decision tool for the omission of PMRT in low-risk elderly patients.

Locoregional breast radiotherapy including IMN: optimizing the dose distribution using an automated non-coplanar VMAT-technique

BACKGROUND

Volumetric Modulated Arc Therapy (VMAT) offers better conformity, homogeneity and sparing of the heart and ipsilateral lung for locoregional radiotherapy in left-sided breast cancer compared to three-dimensional conformal radiotherapy (3D-CRT). However, conventional coplanar VMAT (cVMAT) can result in higher doses to the normal tissue on the contralateral side. This study investigates a non-coplanar VMAT-technique (ncVMAT) to mitigate this issue.

MATERIAL AND METHODS

CT series of 20 left sided breast cancer patients were included for planning of locoregional breast radiotherapy including internal mammary nodes (IMN). Three treatment plans; 3D-CRT, cVMAT and ncVMAT, were generated for each patient with a prescription dose of 40.05 Gy in 15 fractions. Both VMAT-techniques consisted of a single arc in the axial plane, while ncVMAT included an additional arc in the sagittal plane. All plans were optimized to cover the clinical target volume (CTV) by 38.05 Gy for the breast and 36.05 Gy for lymph nodes, with as low as possible dose to organs at risk.

RESULTS

Full CTV coverage was achieved for all plans. Both cVMAT and ncVMAT delivered more conformal and homogeneous target doses than 3D-CRT. Doses to the heart and ipsilateral lung were significantly lower with ncVMAT compared to both cVMAT and 3D-CRT. ncVMAT reduced doses to both the contralateral breast and lung compared to cVMAT and achieved levels similar to 3D-CRT for the contralateral breast and moderately higher doses for the contralateral lung. Delivery of high doses (>30 Gy) to the contralateral side was completely avoided with ncVMAT, contrary to the results for cVMAT and 3D-CRT.

CONCLUSION

ncVMAT reduced doses to the heart and ipsilateral lung as compared to both cVMAT and 3D-CRT. All contralateral dose metrics were reduced with the novel ncVMAT technique compared to cVMAT, and the mean contralateral breast doses were similar to 3D-CRT.

Temporal Trends and Factors Associated with Receipt of Post-mastectomy Radiation After Neoadjuvant Chemotherapy in Women with cT3 Breast Cancer

INTRODUCTION

Given the potential impact of increasingly effective neoadjuvant chemotherapy (NACT) on post-mastectomy radiotherapy (PMRT) recommendations, we examined temporal trends in post-NACT PMRT for cT3 breast cancer.

METHODS

We identified women ≥ 18 years in the National Cancer Database (NCDB) diagnosed 2004-2019 with cT3N0-1M0 breast cancer treated with chemotherapy and mastectomy. Multivariable logistic regression and Cox proportional hazards models were used to estimate associations between pathologic NACT response [complete response (CR), partial response (PR), or no response (NR); or disease progression (DP)] and PMRT and between PMRT and overall survival (OS), respectively.

RESULTS

We identified 39,901 women (Asian/Pacific Islander 1731, Black 5875, Hispanic 3265, White 27,303). Among cN0 patients with CR, PMRT rates declined from 67% in 2004 to 35% in 2019 but remained unchanged for patients with DP. Relative to NR, CR [odds ratio (OR) 0.36, 95% confidence interval (CI) 0.29-0.46] and PR (OR 0.44, 95% CI 0.36-0.55) in cN0 patients were associated with lower odds of PMRT while DP (OR 1.33, 95% CI 1.05-1.69) was associated with higher odds. Among cN1 patients, PMRT rates decreased from 90% to 73% for CR between 2005 and 2019 and increased from 76% to 82% for DP between 2004 and 2019. Relative to NR, CR (OR 0.78, 95% CI 0.63-0.95) was associated with lower odds of PMRT while DP (OR 1.93, 95% CI 1.58-2.37) was associated with higher odds. PMRT was associated with improved OS among cN1 patients (hazard ratio (HR) 0.77, 95% CI 0.67-0.88).

CONCLUSION

CR was associated with decreased PMRT receipt over time, while temporal trends following PR and DP differed by cN status, suggesting that nodal involvement guided PMRT receipt more than in-breast disease.

Explaining risks and benefits of loco-regional treatments to patients

Treatment for early-stage breast cancer is complex, requiring multidisciplinary care with a multitude of treatment options available for each patient. Coupled with the rising importance of shared decision-making, patient-physician conversations are progressively more complicated. These conversations require frank disclosure of risks and benefits of the different treatment modalities in a way that is individualized for each patient and simple to understand. In most patients, breast conserving therapy with radiation should be presented as the gold-standard local treatment given similar long-term and improved quality of life outcomes. De-escalation is currently at the forefront of research in loco-regional treatments, and further investigations are required to best determine the optimal patient populations for reduced sentinel lymph node sampling, omission of sentinel lymph node biopsy altogether and omission of radiation treatment. For future trials, better endpoints need to be established considering patient-centered outcomes as well as recurrence.

Trends and variation in treatment of early breast cancer in European certified breast centres: an EUSOMA-based analysis

BACKGROUND

Practice indicators (PI) measure provided care making use of real-world data. This study describes trends and variations in adjuvant treatment of early breast cancer (EBC) using the European Society of Breast Cancer Specialists (EUSOMA) database.

METHODS

The analysis was conducted on anonymous cumulative data registered by 56 certified breast centres, which all entered at least 500 new diagnoses in the database in the 10-year period 2010-2019. Practice trends of radiotherapy, endocrine treatment, chemotherapy, and anti-HER2 therapy were evaluated. The association with age group (<50, 50-69, ≥70) and geographical area of the centre (Northern, Central, Southern Europe; NE, CE, SE) was assessed with the Pearson Chi2 test for independence in contingency tables.

RESULTS

In total, 150,150 patients with EBC were selected. Overall, radiotherapy was administered more frequently in NE centres, and conversely, endocrine, chemo-, and anti-HER2 therapy were used more frequently in SE centres (p<0.001). 46.9% of the pN1 patients received postmastectomy radiotherapy, with significant differences by age and geographical region (p < 0.001). Adjuvant endocrine treatment for endocrine-sensitive carcinoma in situ was administered in 46.1%, with a decreasing trend during the study period (58.5-34.5%; p < 0.001). Anti-HER2 therapy was delivered in 75.6% of all patients with HER2BC T1a/bN0, patients older than 70 received anti-HER2 in 67.6% in SE compared to 31.3% in NE centres.

CONCLUSION

Important variations in EBC management between European certified breast centres have been demonstrated. PI using real-world data can help to monitor, evaluate, and eventually guide and align good clinical practice in the management of breast cancer.

Lymph node metastasis in cancer progression: molecular mechanisms, clinical significance and therapeutic interventions

Lymph nodes (LNs) are important hubs for metastatic cell arrest and growth, immune modulation, and secondary dissemination to distant sites through a series of mechanisms, and it has been proved that lymph node metastasis (LNM) is an essential prognostic indicator in many different types of cancer. Therefore, it is important for oncologists to understand the mechanisms of tumor cells to metastasize to LNs, as well as how LNM affects the prognosis and therapy of patients with cancer in order to provide patients with accurate disease assessment and effective treatment strategies. In recent years, with the updates in both basic and clinical studies on LNM and the application of advanced medical technologies, much progress has been made in the understanding of the mechanisms of LNM and the strategies for diagnosis and treatment of LNM. In this review, current knowledge of the anatomical and physiological characteristics of LNs, as well as the molecular mechanisms of LNM, are described. The clinical significance of LNM in different anatomical sites is summarized, including the roles of LNM playing in staging, prognostic prediction, and treatment selection for patients with various types of cancers. And the novel exploration and academic disputes of strategies for recognition, diagnosis, and therapeutic interventions of metastatic LNs are also discussed.

Variation in Rates of Post-Mastectomy Radiotherapy Among Women with Early Invasive Breast Cancer in England and Wales: A Population-Based Cohort Study

AIMS

This study examined whether patterns of post-mastectomy radiotherapy (PMRT) among women with early invasive breast cancer (EIBC) varied within England and Wales and explored the role of different patient factors in explaining any variation.

MATERIALS AND METHODS

The study used national cancer data on women aged ≥50 years diagnosed with EIBC (stage I-IIIa) in England and Wales between January 2014 and December 2018 who had a mastectomy within 12 months of diagnosis. A multilevel mixed-effects logistic regression model was used to calculate risk-adjusted rates of PMRT for geographical regions and National Health Service acute care organisations. The study examined the variation in these rates within subgroups of women with different risks of recurrence (low: T1-2N0; intermediate: T3N0/T1-2N1; high: T1-2N2/T3N1-2) and investigated whether the variation was linked to patient case-mix within regions and organisations.

RESULTS

Among 26 228 women, use of PMRT increased with greater recurrence risk (low: 15.0%; intermediate: 59.4%; high: 85.1%). In all risk groups, use of PMRT was more common among women who had received chemotherapy and decreased among women aged ≥80 years. There was weak or no evidence of an association between use of PMRT and comorbidity or frailty, for each risk group. In women with an intermediate risk, unadjusted rates of PMRT varied substantially between geographical regions (range 40.3-77.3%), but varied less for the high-risk (range 77.1-91.6%) and low-risk groups (range 4.1-32.9%). Adjusting for patient case-mix reduced the variation in regional and organisational PMRT rates to a small degree.

CONCLUSIONS

Rates of PMRT are consistently high across England and Wales among women with high-risk EIBC, but variation exists across regions and organisations for women with intermediate-risk EIBC. Effort is required to reduce unwarranted variation in practice for intermediate-risk EIBC.

Locoregional Treatment for Early-Stage Breast Cancer: Current Status and Future Perspectives

BACKGROUND

The locoregional recurrence of breast cancer has been reduced due to the multidisciplinary approach of breast surgery, systemic therapy and radiation. Early detection and better surgical techniques contribute to an improvement in breast cancer outcomes.

PURPOSE OF REVIEW

The purpose of this review is to have an overview and summary of the current evidence behind the current approaches to the locoregional treatment of breast cancer and to discuss its future direction.

SUMMARY

With improved surgical techniques and the use of a more effective neoadjuvant systemic therapy, including checkpoint inhibitors and dual HER2-directed therapies that lead to a higher frequency of pathologic complete responses and advances in adjuvant radiation therapy, breast cancer patients are experiencing better locoregional control and reduced local and systemic recurrence. De-escalation in surgery has not only improved the quality of life in the majority of breast cancer patients, but also maintained the low risk of recurrence. There are ongoing clinical trials to optimize radiation therapy in breast cancer. More modern radiation technologies are evolving to improve the patient outcome and reduce radiation toxicities.

Radiotherapy Use and Incidence of Locoregional Recurrence in Patients With Favorable-Risk, Node-Positive Breast Cancer Enrolled in the SWOG S1007 Trial

Importance

Little is known about regional nodal irradiation (RNI) practice patterns or rates of locoregional recurrence (LRR) with and without RNI in patients with limited nodal disease and favorable biology treated with modern surgical and systemic therapy, including approaches that de-escalate those latter treatments.

Objective

To investigate how often patients with low-recurrence score breast cancer with 1 to 3 nodes involved receive RNI, incidence and predictors of LRR, and associations between locoregional therapy and disease-free survival.

Design, Setting, and Participants

In this secondary analysis of the SWOG S1007 trial, patients with hormone receptor-positive, ERBB2-negative breast cancer, and a Oncotype DX 21-gene Breast Recurrence Score assay result of no more than 25, were randomized to endocrine therapy alone vs chemotherapy then endocrine therapy. Prospectively collected radiotherapy information was collected from 4871 patients treated in diverse settings. Data were analyzed June 2022 to April 2023.

Exposure

Receipt of RNI (targeting at least the supraclavicular region).

Main Outcome(s) and Measure(s)

Cumulative incidence of LRR was calculated by locoregional treatment received. Analyses were assessed for associations between invasive disease-free survival (IDFS) and locoregional therapy, adjusted for menopausal status, treatment group, recurrence score, tumor size, nodes involved, and axillary surgery. Radiotherapy information was recorded in the first year after randomization, so survival analyses were landmarked as starting at 1 year among those still at risk.

Results

Of 4871 female patients (median [range] age, 57 [18-87] years) with radiotherapy forms, 3947 (81.0%) reported radiotherapy receipt. Of 3852 patients who received radiotherapy and had complete information on targets, 2274 (59.0%) received RNI. With a median follow-up of 6.1 years, the cumulative incidence of LRR by 5 years was 0.85% among patients who received breast-conserving surgery and radiotherapy with RNI; 0.55% after breast-conserving surgery with radiotherapy without RNI; 0.11% after mastectomy with postmastectomy radiotherapy; and 1.7% after mastectomy without radiotherapy. Similarly low LRR was observed within the group assigned to endocrine therapy without chemotherapy. The rate of IDFS did not differ by RNI receipt (premenopausal: hazard ratio [HR], 1.03; 95% CI, 0.74-1.43; P = .87; postmenopausal: HR, 0.85; 95% CI, 0.68-1.07; P = .16).

Conclusions and Relevance

In this secondary analysis of a clinical trial, RNI use was divided in the setting of biologically favorable N1 disease, and rates of LRR were low even in patients who did not receive RNI. Disease-free survival was not associated with RNI receipt; omission of chemotherapy among patients similar to those enrolled in the S1007 trial is not an independent indication for use of RNI.

Histology Specific Molecular Biomarkers: Ushering in a New Era of Precision Radiation Oncology

Histopathology and clinical staging have historically formed the backbone for allocation of treatment decisions in oncology. Although this has provided an extremely practical and fruitful approach for decades, it has long been evident that these data alone do not adequately capture the heterogeneity and breadth of disease trajectories experienced by patients. As efficient and affordable DNA and RNA sequencing have become available, the ability to provide precision therapy has become within grasp. This has been realized with systemic oncologic therapy, as targeted therapies have demonstrated immense promise for subsets of patients with oncogene-driver mutations. Further, several studies have evaluated predictive biomarkers for response to systemic therapy within a variety of malignancies. Within radiation oncology, the use of genomics/transcriptomics to guide the use, dose, and fractionation of radiation therapy is rapidly evolving but still in its infancy. The genomic adjusted radiation dose/radiation sensitivity index is one such early and exciting effort to provide genomically guided radiation dosing with a pan-cancer approach. In addition to this broad method, a histology specific approach to precision radiation therapy is also underway. Herein we review select literature surrounding the use of histology specific, molecular biomarkers to allow for precision radiotherapy with the greatest emphasis on commercially available and prospectively validated biomarkers.

Efficacy of post‑mastectomy radiotherapy in patients with T1‑2N1 breast cancer aged ≤35 years or with a positive HER‑2 status

Post-mastectomy radiotherapy (PMRT) is highly recommended for patients with breast cancer with one to three positive nodes; however, there remains some controversy regarding its use. The present retrospective study aimed to explore which patients may be able to avoid PMRT and its associated side effects. A total of 728 patients with T1-2N1 breast cancer who were treated with or without PMRT were included in the present study. The results suggested that PMRT significantly decreased the locoregional recurrence rate (LRR) [hazard ratio (HR)=5.602, 95% confidence interval (CI)=3.139-9.998, P<0.01; 3-year LRR: 4 vs. 17%] and improved overall survival (OS) (HR=0.651, 95% CI=0.437-0.971, P=0.03; 3-year OS: 91 vs. 87%) for patients with T1-2N1 breast cancer. By contrast, PMRT had no significant effect on the distant metastasis (DM) rate (HR=0.691, 95% CI=0.468-1.019, P=0.06; 3-year DM: 10 vs. 15%). Further stratified analysis revealed that PMRT did not reduce the LRR and DM, or improve OS in patients aged ≤35 years or in those with a positive human epidermal growth factor receptor-2 (HER-2) status. The analysis of 438 patients treated with PMRT revealed that patients aged ≤35 years or those with a positive HER-2 status were more likely to experience local recurrence even following PMRT. Thus, the benefits of using PMRT in patients with T1-2N1 breast cancer who are aged ≤35 years or in those with a positive HER-2 status need to be carefully considered. Further studies are required to confirm whether this patient group may be exempted from PMRT.

Advances in Radiotherapy for Breast Cancer

Breast cancer is the most prevalent cancer in women, and the second leading cause of cancer death in women in the United States. Radiation therapy is an important component in the multimodal management of breast cancer, including early stage and locally advanced breast cancers, as well as metastatic cases. Breast cancer radiation therapy has seen significant advancements over the past 20 years. This article discusses the latest advances in the radiotherapeutic management of breast cancer, especially focusing on the technological advances in radiation treatment planning and techniques that have exploited the understanding of radiation biology.

Post-mastectomy radiotherapy for women with early breast cancer and one to three positive lymph nodes

BACKGROUND

Continual improvement in adjuvant therapies has resulted in a better prognosis for women diagnosed with breast cancer. A surrogate marker used to detect the spread of disease after treatment of breast cancer is local and regional recurrence. The risk of local and regional recurrence after mastectomy increases with the number of axillary lymph nodes affected by cancer. There is a consensus to use radiotherapy as an adjuvant treatment after mastectomy (postmastectomy radiotherapy (PMRT)) in women diagnosed with breast cancer and found to have disease in four or more positive axillary lymph nodes. Despite data showing almost double the risk of local and regional recurrence in women treated with mastectomy and found to have one to three positive lymph nodes, there is a lack of international consensus on the use of PMRT in this group.

OBJECTIVES

To assess the effects of PMRT in women diagnosed with early breast cancer and found to have one to three positive axillary lymph nodes.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group's Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov up to 24 September 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs). The inclusion criteria included women diagnosed with breast cancer treated with simple or modified radical mastectomy and axillary surgery (sentinel lymph node biopsy (SLNB) alone or those undergoing axillary lymph node clearance with or without prior SLNB). We included only women receiving PMRT using X-rays (electron and photon radiation), and we defined the radiotherapy dose to reflect what is currently being recommended (i.e. 40 Gray (Gy) to 50 Gy in 15 to 25/28 fractions in 3 to 5 weeks. The included studies did not administer any boost to the tumour bed. In this review, we excluded studies using neoadjuvant chemotherapy as a supportive treatment before surgery.

DATA COLLECTION AND ANALYSIS

We used Covidence to screen records. We collected data on tumour characteristics, adjuvant treatments and the outcomes of local and regional recurrence, overall survival, disease-free survival, time to progression, short- and long-term adverse events and quality of life. We reported on time-to-event outcome measures using the hazard ratio (HR) and subdistribution HR. We used Cochrane's risk of bias tool (RoB 1), and we presented overall certainty of the evidence using the GRADE approach.

MAIN RESULTS

The RCTs included in this review were subgroup analyses of original RCTs conducted in the 1980s to assess the effectiveness of PMRT. Hence, the type and duration of adjuvant systemic treatments used in the studies included in this review were suboptimal compared to the current standard of care. The review involved three RCTs with a total of 829 women diagnosed with breast cancer and low-volume axillary disease. Amongst the included studies, only a single study pertained to the modern-day radiotherapy practice. The results from this one study showed a reduction of local and regional recurrence (HR 0.20, 95% confidence interval (CI) 0.13 to 0.33, 1 study, 522 women; low-certainty evidence) and improvement in overall survival with PMRT (HR 0.76, 95% CI 0.60 to 0.97, 1 study, 522 women; moderate-certainty evidence). One of the other studies using radiotherapy techniques that do not reflect modern-day practice reported on disease-free survival in women with low-volume axillary disease (subdistribution HR 0.63, 95% CI 0.41 to 0.96, 1 study, 173 women). None of the included studies reported on PMRT side effects or quality-of-life outcome measures.

AUTHORS' CONCLUSIONS

Based on one study, the use of PMRT in women diagnosed with breast cancer and low-volume axillary disease indicated a reduction in locoregional recurrence and an improvement in survival. There is a need for more research to be conducted using modern-day radiotherapy equipment and methods to support and supplement the review findings.

Breast cancer survival and the health system in Brazil: an analysis of public and private healthcare

Background

The incidence of breast cancer is increasing globally; however, survival outcomes vary and are lower in developing countries.

Methods

We analyzed the 5- and 10-year survival rates for breast cancer according to the type of healthcare insurance (public vs. private) in a referral center for cancer care in the Brazilian southeast region. This hospital-based cohort study included 517 women diagnosed with invasive breast cancer between 2003 and 2005. The Kaplan-Meier method was used to estimate the probability of survival, and the Cox proportional hazards regression model was used to assess prognostic factors.

Results

The 5- and 10-year breast cancer survival rates were as follows: private healthcare service survival rate of 80.6% (95% CI 75.0-85.0) and 71.5% (95% CI 65.4-77.1), respectively, and public healthcare service survival rate of 68.5% (95% CI 62.5-73.8) and 58.5% (95% CI 52.1-64.4), respectively. The main factors associated with the worst prognosis were lymph node involvement in both healthcare services and tumor size >2 cm only in public health services. The use of hormone therapy (private) and radiotherapy (public) was associated with the best survival rates.

Conclusions

The survival discrepancies found between health services can be explained mainly by the difference in the stage of the disease at the time of diagnosis, indicating inequalities in access to the early detection of breast cancer.

Post-mastectomy Radiation Therapy in HER-2 Positive Breast Cancer after Primary Systemic Therapy: Pooled Analysis of TRYPHAENA and NeoSphere Trials

PURPOSE

The role of post-mastectomy radiation therapy (PMRT) following primary systemic therapy (PST) in HER-2 positive breast cancer (Her2+BC) remains poorly understood. The current study evaluates PMRT based on the pathological response to PST in Her2+BC.

METHODS AND MATERIALS

TRYPHAENA and NeoSphere are randomized phase II trials that investigated PST for Her2+BC. Our study is a pooled analysis of both trials, including 312 node-positive patients treated with HER-2 targeted PST followed by mastectomy with or without PMRT. The primary endpoint is loco-regional recurrence-free survival (LRRFS).

RESULTS

Our analysis included 172 (55%) patients who achieved complete nodal pathological response (ypN0) and 140 (45%) patients who did not. Patients with ypN0 had a 5-year LRRFS of 97% in both, the PMRT and no PMRT, groups (p=0.94). Patients with ypN+ had 5-year LRRFS of 89% in the PMRT group and 82% in the no PMRT group (p=0.17). Patients with ypN1 (n=62) disease who received PMRT (n=40) had a 5-year LRRFS of 85% as compared to 89% in those who did not (n=22); (p=0.60). A significant LRRFS difference was noted in patients with ypN2-3 (n=78) disease who received PMRT (n=53) compared to those who did not (n=25) (5-year LRRFS 92% vs. 75%; p=0.019). On multivariate analysis, clinical nodal disease at diagnosis and ypN0 were significantly associated with loco-regional recurrence (LRR).

CONCLUSIONS

Her2+BC patients who achieve ypN0 after PST have excellent locoregional-control which supports de-escalation of PMRT. In contrast, patients with ypN2-3 disease derive significant benefit from PMRT. Clinical nodal stage at presentation and ypN0 status are significantly associated with LRR risk in Her2+BC.

Predictors of cardiac dose sparing in deep inspiratory breath-hold technique for radiation of left breast cancer patients

Introduction

Radiation therapy to left breast cancer patients results in significant exposure to heart resulting in long-term cardiac morbidity. This exposure can be reduced by performing deep inspiratory breath-hold (DIBH) technique, however, patient selection criteria or predictive parameters are not routinely used which can identify patients who will have significant benefit with this technique. This study intends to find and use these predictive parameters measured on free-breathing (FB) simulation scan which can help to select such patients so as to develop our institutional protocol.

Methods

A total of 35 patients of left breast cancer postsurgery were recruited in the study. All patients underwent 2-3 sessions of DIBH coaching followed by planning computed tomography scan in both FB phase and DIBH phase. Various anatomical parameters such as cardiac contact distance parasagittal (CCDps), CCD axial, heart-chest distance (HCD), and D were measured on FB scan and were correlated with a mean heart dose achieved in DIBH scan.

Results

Dose to normal structures, namely heart and lung, was drastically reduced for DIBH scan over FB scan. V5, V10, and V20 of heart also followed a similar reduction. The mean dose to heart in FB scan was 5.34 Gy, while in DIBH scan, it was 2.79 Gy which was statistically significant. Among all the parameters measured, CCDps and D had a statistically significant positive correlation with the mean heart dose in DIBH phase while HCD had a negative correlation which was statistically significant.

Conclusion

Cardiac parameters on FB scan such as CCDps, HCD, and D predict the patients with usual cardiac risk who will benefit most with DIBH techniques setting an arbitrarily cutoff value.