DEGRO practical guidelines for radiotherapy of breast cancer VI: therapy of locoregional breast cancer recurrences

[Reirradiation of recurrent breast carcinoma]

Approximately 10 to 15% of patients with breast cancer will have a local recurrence after initial conservative treatment or mastectomy. Total mastectomy has historically been the standard treatment for local recurrence. However, the question of reirradiation may arise as part of a second conservative treatment in conjunction with segmentectomy or in the case of chest wall recurrence to improve local control. Different modalities are available: brachytherapy, external beam radiotherapy with or without hyperthermia. Although the carcinologic results are encouraging, this complex situation requires rigorous patient selection and technical requirements to achieve the best local control and limit toxicity events. This article presents a review of the literature on the different indications and techniques for reirradiation of ipsilateral recurrent breast cancer, with the aim of providing decision support in clinical practice.

Salvage Breast-Conserving Surgery and Reirradiation With Intraoperative Electrons for Recurrent Breast Cancer: A Multicentric Study on Behalf of Italian Association of Radiotherapy and Clinical Oncology (AIRO)

PURPOSE

Intraoperative radiation therapy with electrons (IOERT) may represent a viable choice for partial breast reirradiation after repeat quadrantectomy for local recurrence (LR) for primary breast cancer (BC) in lieu of mastectomy.

METHODS AND MATERIALS

A database collecting data on partial breast reirradiation with IOERT from 8 Italian centers was set up in 2016 to 2018, providing data on cumulative incidence (CumI) of second LR and survival with a long follow-up.

RESULTS

From 2002 to 2015, 109 patients underwent the conservative retreatment. The median primary BC first LR interval was 11.1 years (range, 2.4-27.7). The median first LR size was 0.9 cm (range, 0.3-3.0), and 43.6% cases were luminal A. Median IOERT dose was 18 Gy (range, 12-21), and median collimator diameter was 4 cm (range, 3-6). Median follow-up duration was 11.7 years (IQR, 7.7-14.6). The second LR CumI was 12.2% (95% CI, 6.8%-19.2%) at 5 years and 32.3% at 10 years (95% CI, 22.8%-42.2%), occurring in the same site as the first LR in about half of the cases. Human epidermal growth factor receptor 2 status and collimator size were independent LR predictors. The 5- and 10-year overall survival rates were 95.2% and 88.3%, respectively, whereas 5- and 10-year BC-specific survival rates were 98% and 94.5%, respectively. The development of a second LR significantly reduced BC-specific survival (hazard ratio, 9.40; P < .001). Grade ≥3 fibrosis rate was 18.9%. Patient-reported cosmesis was good/excellent in 59.7% of the cases.

CONCLUSIONS

Second LR CumI was within the range of the literature but higher than expected, opening questions on radiation field extension and fractionation schedule. Because a second LR worsened the outcome, salvage modality must be carefully planned.

Long-Term Oncologic Outcomes of Omitting Axillary Surgery in Breast Cancer Patients with Chest Wall Recurrence after Mastectomy

BACKGROUND

The management of the axilla in breast cancer patients with isolated chest wall recurrence (CWR) after mastectomy remains controversial. Although sentinel lymph node biopsy (SLNB) for restaging is feasible, its role is unclear. We aimed to determine if the omission of axillary restaging surgery in female patients with operable presumably isolated CWRs could result in an increased risk of second recurrences.

METHODS

In this retrospective multicentre study, patients who developed CWRs were reviewed. We excluded patients with suspected or concomitant regional/distant metastases, bilateral cancers and patients without CWR surgery. Patients' demographics, pathological data and subsequent recurrences were collected from a prospective database and were compared between patients with axillary lymph node dissection (ALND) and/or SLNB versus no axillary operation at CWR.

FINDINGS

A total of 194 patients with CWRs were eligible. The median age at CWR was 56.0 (IQR 47.0-67.0) years old. At recurrence, 8 (4.1%), 5 (2.6%) and 181 (93.3%) patients had ALND, SLNB and no axillary operation, respectively. Patients with no axillary surgery during CWR were associated with, at primary cancer, a lower incidence of ductal carcinoma in situ as diagnosis (p = 0.007) and older age (p = 0.022). Subsequent ipsilateral axillary (p = 0.768) and second recurrences (p = 0.061) were not statistically different between patients with and without axillary surgery at CWR on median follow-up of 59.5 (IQR 27.3-105) months.

INTERPRETATION

In patients without evidence of concomitant regional or distant metastasis at CWR diagnosis, omission of axillary restaging surgery was not associated with an increased ipsilateral axillary or second recurrences on long-term follow-up.

Hypofractionated Partial Breast Reirradiation in the Conservative Retreatment of Breast Cancer Local Recurrence

PURPOSE

To evaluate the outcome of partial breast reirradiation (re-PBI) with intensity modulated radiation therapy using a hypofractionated scheme for breast cancer (BC) local relapse (LR) operated on with repeat breast-conservative surgery.

METHODS AND MATERIALS

Intensity modulated radiation therapy-based re-PBI was performed using either helical or step-and-shoot modality to deliver 37.05 Gy in 13 fractions in 2.5 weeks. Cumulative incidence of second LR, toxicity, disease-free survival (DFS), BC-specific survival, and overall survival were evaluated.

RESULTS

Between May 2012 and May 2021, 70 patients had re-PBI. The median follow-up (FU) was 6.3 years (quartiles 1-3, 4.0-8.1.). The median age at first LR was 62 years. The median primary BC first LR interval was 12.4 years (range, 1.6-26.7 years). Luminal A-like first LR accounted for 41% of the cases, and the median size was 0.8 cm. During FU, 18 (26%) patients showed a subsequent event: 3 second LRs (corresponding to an 8-year cumulative rate of 4%), 3 regional nodal recurrences, 7 distant metastases, and 5 other primary tumors. At 8 years, DFS, BC-specific survival, and overall survival were 76%, 90%, and 90%, respectively. At multivariate analysis, grade 3 and extensive intraductal components were independent predictors for DFS. For 51 and 46 patients, chronic toxicity and cosmesis were evaluated, respectively: 4% had grade 3 fibrosis, and cosmesis was deemed good/excellent in just >60% of the cases.

CONCLUSIONS

Re-PBI after repeat breast-conservative surgery represents a feasible alternative to mastectomy with regard to local control, showing an acceptable toxicity profile. A long-term FU is crucial to better understand the pattern of relapse and consolidate the position of re-PBI in clinical practice.

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.

Tools to Guide Radiation Oncologists in the Management of DCIS

Similar to invasive breast cancer, ductal carcinoma in situ is also going through a phase of changes not only from a technical but also a conceptual standpoint. From prescribing radiotherapy to everyone to personalized approaches, including radiotherapy omission, there is still a lack of a comprehensive framework to guide radiation oncologists in decision making. Many pieces of the puzzle are finding their place as high-quality data mature and are disseminated, but very often, the interpretation of risk factors and the perception of risk remain very highly subjective. Sharing the therapeutic choice with patients requires effective communication for an understanding of risks and benefits, facilitating an informed decision that does not increase anxiety and concerns about prognosis. The purpose of this narrative review is to summarize the current state of knowledge to highlight the tools available to radiation oncologists for managing DCIS, with an outlook on future developments.

Management of second ipsilateral breast tumor event: An advocacy for a randomized trial

For a second ipsilateral breast tumor event, salvage mastectomy is the standard of care while second conservative treatment is a possible option. However, level 1 proofs are missing, leading to perform salvage mastectomy for patients who could receive second conservative treatment and consequently avoid psychological/quality of life salvage mastectomy deleterious impacts. A phase 3 randomized trial comparing salvage mastectomy to second conservative treatment is needed. Here we discuss what would be to us the optimal design of such trial to confirm the non-inferiority between the two salvage options, with a focus on methodological aspects in terms of patient characteristics and statistical issues.

Protocol of the HISTOTHERM study: assessing the response to hyperthermia and hypofractionated radiotherapy in recurrent breast cancer

Introduction

Breast cancer is globally the leading cancer in women, and despite the high 5-year survival rate the most frequent cause of cancer related deaths. Surgery, systemic therapy and radiotherapy are the three pillars of curative breast cancer treatment. However, locoregional recurrences frequently occur after initial treatment and are often challenging to treat, amongst others due to high doses of previous radiotherapy treatments. Radiotherapy can be combined with local hyperthermia to sensitize tumor cells to radiation and thereby significantly reduce the required radiation dose. Therefore, the combination treatment of mild local hyperthermia, i.e. locally heating of the tissue to 39-43°C, and re-irradiation with a reduced total dose is a relevant treatment option for previously irradiated patients. The mechanisms of this effect in the course of the therapy are to date not well understood and will be investigated in the HISTOTHERM study.

Methods and analyses

Patients with local or (loco)regional recurrent breast cancer with macroscopic tumors are included in the study. Local tumor control is evaluated clinically and histologically during the course of a combination treatment of 60 minutes mild superficial hyperthermia (39 - 43°C) using water-filtered infrared A (wIRA) irradiation, immediately followed by hypofractionated re-irradiation with a total dose of 20-24 Gy, administered in weekly doses of 4 Gy. Tumor and tumor stroma biopsies as well as blood samples will be collected prior to treatment, during therapy (at a dose of 12 Gy) and in the follow-up to monitor therapy response. The treatment represents the standard operating procedure for hyperthermia plus re-irradiation. Various tissue and blood-based markers are analyzed. We aim at pinpointing key mechanisms and markers for therapy response which may help guiding treatment decisions in future. In addition, quality of life in the course of treatment will be assessed and survival data will be evaluated.

Registration

The study is registered at the German Clinical Trials Register, Deutsches Register Klinischer Studien (DRKS00029221).

Re-irradiation in clinical practice: Results of an international patterns of care survey within the framework of the ESTRO-EORTC E2-RADIatE platform

BACKGROUND

Re-irradiation is an increasingly utilized treatment for recurrent, metastatic or new malignancies after previous radiotherapy. It is unclear how re-irradiation is applied in clinical practice. We aimed to investigate the patterns of care of re-irradiation internationally.

MATERIAL/METHODS

A cross-sectional survey conducted between March and September 2022. The survey was structured into six sections, each corresponding to a specific anatomical region. Participants were instructed to complete the sections of their clinical expertise. A total of 15 multiple-choice questions were included in each section, addressing various aspects of the re-irradiation process. The online survey targeted radiation and clinical oncologists and was endorsed by the European Society for Radiotherapy and Oncology (ESTRO) and the European Organisation for Research and Treatment of Cancer (EORTC).

RESULTS

371 physicians from 55 countries across six continents participated. Participants had a median professional experience of 16 years, and the majority (60%) were affiliated with an academic hospital. The brain region was the most common site for re-irradiation (77%), followed by the pelvis (65%) and head and neck (63%). Prolonging local control was the most common goal (90-96% across anatomical regions). The most common minimum interval between previous radiotherapy and re-irradiation was 6-12 months (45-55%). Persistent grade 3 or greater radiation-induced toxicity (77-80%) was the leading contraindication. Variability in organs at risk dose constraints for re-irradiation was observed. Advanced imaging modalities and conformal radiotherapy techniques were predominantly used. A scarcity of institutional guidelines for re-irradiation was reported (16-19%). Participants from European centers more frequently applied thoracic and abdominal re-irradiation. Indications did not differ between academic and non-academic hospitals.

CONCLUSION

This study highlights the heterogeneity in re-irradiation practices across anatomical regions and emphasizes the need for high-quality evidence from prospective studies to guide treatment decisions and derive safe cumulative dose constraints.

Prospective randomized clinical studies involving reirradiation: update of a systematic review

BACKGROUND

Reirradiation is a potentially useful option for many patients with recurrent cancer, aiming at cure or symptom palliation, depending on disease/recurrence type and stage. The purpose of this follow-up study to a previous review from 2016 was to summarize all recently published randomized trials. Points of interest again included identifcation of methodological strengths and weaknesses, practice-changing results, and open questions.

MATERIAL AND METHODS

Systematic review of trials published between 2015 and February 2023.

RESULTS

We reviewed 7 additional trials, most of which addressed reirradiation of head and neck or brain tumours. The median number of patients was 60. Mirroring the previous review, trial design, primary endpoints and statistical hypotheses varied widely. The updated results only impact on decision making for reirradiation of nasopharynx cancer and glioma. Patients with one of these diseases, as well as other head and neck cancers, may benefit from reirradiation-induced local control, e.g. in terms of progression-free survival. For the first time, hyperfractionated radiotherapy emerged as preferred option for recurrent, inoperable nasopharynx cancer. Despite better therapeutic ratio with hyperfractionation, serious toxicity remains a concern after high cumulative total doses. Randomized trials are still lacking for prostate cancer and other sites.

CONCLUSION

Multicentric randomized trials on reirradiation are feasible and continue to refine the current standard of care for recurrent disease after previous radiotherapy. Ongoing prospective studies such as the European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer (ESTRO-EORTC) observational cohort ReCare (NCT: NCT03818503) will further shape the clinical practice of reirradiation.

The 2022 Assisi Think Tank Meeting: White paper on optimising radiation therapy for breast cancer

The present white paper, referring to the 4th Assisi Think Tank Meeting on breast cancer, reviews state-of-the-art data, on-going studies and research proposals. < 70% agreement in an online questionnaire identified the following clinical challenges: 1: Nodal RT in patients who have a) 1-2 positive sentinel nodes without ALND (axillary lymph node dissection); b) cN1 disease transformed into ypN0 by primary systemic therapy and c) 1-3 positive nodes after mastectomy and ALND. 2. The optimal combination of RT and immunotherapy (IT), patient selection, IT-RT timing, and RT optimal dose, fractionation and target volume. Most experts agreed that RT- IT combination does not enhance toxicity. 3: Re-irradiation for local relapse converged on the use of partial breast irradiation after second breast conserving surgery. Hyperthermia aroused support but is not widely available. Further studies are required to finetune best practice, especially given the increasing use of re-irradiation.

Prognostic factors after isolated ipsilateral local and regional recurrence in HER2-negative luminal breast cancer: a multi-center retrospective study

BACKGROUND

Although the incidence of isolated ipsilateral local and regional recurrence (IILRR) in human epidermal growth factor 2 (HER2)-negative luminal breast cancer is low, it is important because of its potential risk of distant metastasis and breast cancer related mortality. The aim of this study was to investigate prognostic factor and survival of IILRR using a large multi-center cohort.

METHODS

Data on patients with HER2-negative luminal breast cancer between 2005 and 2015 were retrieved. The endpoint was IILRR rate, post-recurrence progression-free survival (P-PFS), and post-recurrence overall survival (P-OS). Prognostic factors for progression and overall survival (OS) after IILRR were assessed by multivariate analysis.

RESULTS

Eighty (2.37%) patients experienced IILRR. Of them, 27 (33.7%) experienced a disease progression, including 23 (85.2%) who had distant metastasis. The median DFS was 48.5 months (range, 4-138 months). In 72.5% of cases, the first IILRR occurred after 3 years. Estimated 5-year P-PFS rates were 86.2%, 69.7%, 69.0%, 42.7%, and 82.2% for patients with age < 40 at diagnosis (p = 0.015), T1 stage (p = 0.012), stage I (p < 0.001), lymphovascular invasion (p = 0.003), and patients with post-recurrence endocrine therapy (p < 0.001), respectively. The 5-year Kaplan-Meier P-OS rate for patients was 81.4%. Post-recurrence endocrine therapy was independent factor for progression (HR: 0.176, p < 0.001) and OS (HR: 0.080, p < 0.001).

CONCLUSIONS

Although there is no standardized treatment for IILRR yet, endocrine therapy after local resection plays a more important role in improving prognosis than chemotherapy or radiotherapy in HER2-negative luminal breast cancer.

Salvage Perioperative Interstitial High-Dose-Rate Interventional Radiotherapy (Brachytherapy) for Local Recurrences of the Chest Wall Following Mastectomy and Previous External Irradiation

(1) Background: To investigate the technical feasibility, safety, and efficacy of interstitial perioperative high-dose-rate interventional radiotherapy (HDR-IRT, brachytherapy) as a local salvage treatment combined with surgery for local chest wall recurrences following mastectomy and subsequent external beam radiation treatment (EBRT). (2) Methods: A retrospective analysis of 56 patients treated with interstitial HDR-IRT in combination with local surgery of a chest wall recurrence of breast cancer after previous treatment with mastectomy and EBRT from 2008 to 2020. (3) Results: Local recurrence following HDR-IRT was encountered in seven (12.5%) patients. The 1-year local recurrence-free survival (RFS), 3-year RFS, and 5-year RFS were 91%, 82%, and 82%, respectively. The 1-year overall survival (OS), 3-year OS, and 5-year OS was 85.5%, 58%, and 30%, respectively. Acute grade 1-2 radiation dermatitis was observed in 22 (39.3%) patients. Late ≥grade 3 toxicities were encountered in five (8.9%) patients. (4) Conclusions: Salvage perioperative interstitial high-dose-rate interventional radiotherapy (brachytherapy) combined with surgery seems to be an effective interdisciplinary management with acceptable treatment-related toxicity for local recurrences of the chest wall following mastectomy and previous external irradiation.

European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer consensus on re-irradiation: definition, reporting, and clinical decision making

Re-irradiation can be considered for local recurrence or new tumours adjacent to a previously irradiated site to achieve durable local control for patients with cancer who have otherwise few therapeutic options. With the use of new radiotherapy techniques, which allow for conformal treatment plans, image guidance, and short fractionation schemes, the use of re-irradiation for different sites is increasing in clinical settings. Yet, prospective evidence on re-irradiation is scarce and our understanding of the underlying radiobiology is poor. Our consensus on re-irradiation aims to assist in re-irradiation decision making, and to standardise the classification of different forms of re-irradiation and reporting. The consensus has been endorsed by the European Society for Radiotherapy and Oncology and the European Organisation for Research and Treatment of Cancer. The use of this classification in daily clinical practice and research will facilitate accurate understanding of the clinical implications of re-irradiation and allow for cross-study comparisons. Data gathered in a uniform manner could be used in the future to make recommendations for re-irradiation on the basis of clinical evidence. The consensus document is based on an adapted Delphi process and a systematic review of the literature was done according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

Is repeat breast conservation possible for small ipsilateral breast cancer recurrence?

BACKGROUND

Most cases of ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery (BCS) involve small tumors. Although a few guidelines recommend mastectomy, several patients prefer repeat BCS (re-BCS). This study aimed to compare re-BCS and mastectomy in terms of prognosis in patients with IBTR and to identify candidates for re-BCS.

METHODS

The data of patients with small IBTR between 1999 and 2015 were obtained from the Surveillance, Epidemiology, and End Results database. The outcomes of interest were overall survival (OS) and breast cancer-specific survival (BCSS). Multivariable Cox proportional hazards regression models and propensity score matching were applied.

RESULTS

Of the 3648 patients with IBTR, 2831 (77.6%) underwent mastectomy and 817 (22.4%) underwent re-BCS. The multivariate Cox model showed that re-BCS was associated with a worse OS (hazard ratio [HR], 1.342; 95% confidence interval [CI], 1.084-1.663) and BCSS (HR, 1.454; 95% CI, 1.004-2.105) compared with mastectomy. The omission of radiation after re-BCS was associated with worse survival overall and especially in patients with estrogen receptor (ER)-negative IBTR (HR, 1.384; 95% CI, 1.110-1.724; and HR, 1.577; 95% CI, 1.075-2.314, respectively). No statistically significant differences were observed in the OS and BCSS between re-BCS with radiation and mastectomy. Subgroup analysis indicated that the surgical approach was not an independent factor for survival in the ER-positive patients with IBTR.

CONCLUSIONS

Re-BCS should be considered with caution in patients with small IBTR. However, a positive ER status can be an important factor for choosing re-BCS, and radiation therapy may improve oncological safety after re-BCS.

LAY SUMMARY

Repeat breast-conserving surgery (re-BCS) was investigated to determine if it is safe for patients with small ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery (BCS). This population-based cohort study included 2831 patients with small IBTR. Re-BCS was associated with a worse overall survival and breast cancer-specific survival compared with mastectomy. Further analysis found that the IBTR estrogen receptor status was an important basis for choosing re-BCS, and radiation may improve oncological safety after re-BCS.

Multidisciplinary management and role of reirradiation in the treatment of a breast cancer patient with four locoregional recurrences

Breast cancer is a frequent and sometimes fatal disease. The risk of locoregional recurrence has considerably decreased since the introduction of adjuvant treatments (radiotherapy, chemotherapy, hormone therapy). Nevertheless, some patients present a risk of multiple local recurrences. We report here the case of a patient who had four locoregional breast cancer recurrences. There is currently no validated biomarker that allows the prediction of recurrence. Salvage surgery, most often mastectomy, remains the recommended treatment for the management of these recurrences in the irradiated field. However, increasingly, depending on the patient's wishes and the technical possibilities of multiple surgeries, the question of a second conservative treatment and reirradiation arises. This type of management must in all cases be multidisciplinary and in specialized centers. Reirradiation must in any case try to give maximum priority to the protection of healthy tissue already irradiated.

A Systematic Review and Meta-Analysis on the Role of Repeat Breast-Conserving Surgery for the Management of Ipsilateral Breast Cancer Recurrence

INTRODUCTION

The standard surgical management of ipsilateral breast cancer recurrence (IBCR) in patients previously treated with breast-conserving surgery (BCS) and radiotherapy (RT) is mastectomy. Recent international guidelines provide conflicting recommendations. The aim of this study was to perform a systematic literature review and meta-analysis of the oncological outcomes in patients with IBCR treated with repeat BCS (rBCS).

METHODS

The MEDLINE and EMBASE databases were searched for relevant English-language publications, with no date restrictions. All relevant studies providing sufficient data to assess oncological outcomes (second local recurrence [LR] and overall survival [OS]) of rBCS for the management of IBCR after previous BCS and RT were included (PROSPERO registration CRD42021286123).

RESULTS

Forty-two observational studies met the criteria and were included in the analysis. The pooled second LR rate after rBCS was 15.7% (95% confidence interval [CI] 12.1-19.7), and 10.3% (95% CI 6.9-14.3) after salvage mastectomy. On meta-analysis of comparative studies (n = 17), the risk ratio (RR) for second LR following rBCS compared with mastectomy was 2.103 (95% CI 1.535-2.883; p < 0.001, I² = 55.1%). Repeat RT had a protective effect (coefficient: - 0.317, 95% CI - 0.596 to - 0.038; p = 0.026, I² = 40.4%) for second LR. Pooled 5-year OS was 86.8% (95% CI 83.4-90.0) and 79.8% (95% CI 74.7-84.5) for rBCS and salvage mastectomy, respectively. Meta-analysis of comparative studies (n = 20) showed a small OS benefit in favor of rBCS (RR 1.040, 95% CI 1.003-1.079; p = 0.032, I² = 70.8%). Overall evidence certainty was very low.

CONCLUSIONS

This meta-analysis suggests rBCS could be considered as an option for the management of IBCR in patients previously treated with BCS and RT. Shared decision making, appropriate patient selection, and individualized approach are important for optimal outcomes.

Post-operative re-irradiation with hyperthermia in locoregional breast cancer recurrence: Temperature matters

PURPOSE

To investigate the impact of hyperthermia thermal dose (TD) on locoregional control (LRC), overall survival (OS) and toxicity in locoregional recurrent breast cancer patients treated with postoperative re-irradiation and hyperthermia.

METHODS

In this retrospective study, 112 women with resected locoregional recurrent breast cancer treated in 2010-2017 with postoperative re-irradiation 8frx4Gy (n = 34) or 23frx2Gy (n = 78), combined with 4-5 weekly hyperthermia sessions guided by invasive thermometry, were subdivided into 'low' (n = 56) and 'high' TD (n = 56) groups by the best session with highest median cumulative equivalent minutes at 43 °C (Best CEM43T50) < 7.2 min and ≥7.2 min, respectively. Actuarial LRC, OS and late toxicity incidence were analyzed. Backward multivariable Cox regression and inverse probability weighting (IPW) analysis were performed.

RESULTS

TD subgroups showed no significant differences in patient/treatment characteristics. Median follow-up was 43 months (range 1-107 months). High vs. low TD was associated with LRC (p = 0.0013), but not with OS (p = 0.29) or late toxicity (p = 0.58). Three-year LRC was 74.0% vs. 92.3% in the low and high TD group, respectively (p = 0.008). After three years, 25.0% and 0.9% of the patients had late toxicity grade 3 and 4, respectively. Multivariable analysis showed that distant metastasis (HR 17.6; 95%CI 5.2-60.2), lymph node involvement (HR 2.9; 95%CI 1.2-7.2), recurrence site (chest wall vs. breast; HR 4.6; 95%CI 1.8-11.6) and TD (low vs. high; HR 4.1; 95%CI 1.4-11.5) were associated with LRC. TD was associated with LRC in IPW analysis (p = 0.0018).

CONCLUSIONS

High thermal dose (best CEM43T50 ≥ 7.2 min) was associated with significantly higher LRC for patients with locoregional recurrent breast cancer treated with postoperative re-irradiation and hyperthermia, without augmenting toxicity.

The POLO (Partially Omitted Lobe) approach to safely treat in-breast recurrence after intraoperative radiotherapy with electrons

OBJECTIVES

The aim of this study is to evaluate feasibility of salvage 4-week hypofractionated whole breast radiotherapy (WBRT) in patients with in-breast recurrence after receiving intraoperative radiotherapy with electrons (IOERT) for primary breast cancer (BC).

METHODS

BC patients who had repeated quadrantectomy underwent modified WBRT with intensity-modulated radiotherapy using Helical Tomotherapy to underdose the IOERT region. This approach, called POLO (Partially Omitted Lobe), excluded the IOERT volume from receiving the full prescription dose.

RESULTS

Nine patients were treated with this approach, receiving 45 Gy in 20 fractions. A simultaneous integrated boost of 2.5 Gy in 20 fractions was delivered in 6/9 patients. Dose constraints and planning objectives were reported. No severe toxicity was reported while local control and overall survival were 100%.

CONCLUSION

The POLO approach is technically feasible and capable to achieve a significant reduction of radiation dose delivered to the previous treated IOERT area.

ADVANCES IN KNOWLEDGE

The study demonstrates the technical and dosimetric feasibility of conservative salvage whole breast radiotherapy, while sparing the area already treated with IORT, in patients with in-breast recurrence.

Repeat Breast-Conserving Surgery Versus Salvage Mastectomy for Ipsilateral Breast Tumour Recurrence After Breast-Conserving Surgery in Breast Cancer Patients: A Meta-Analysis

Background

Salvage mastectomy (SM) is the standard surgery for ipsilateral breast tumour recurrence (IBTR). However, whether repeat breast-conserving surgery (RBCS) is an alternative method remains unclear. We performed a meta-analysis to compare the effects of RBCS and SM after IBTR for breast-conserving surgery (BCS).

Methods

We searched PubMed, Cochrane, Wiley Online and Embase for controlled studies comparing RBCS and SM after IBTR for BCS (published between 1993 and 2019, published in English). Our main endpoints were the secondary local recurrence rate (SLRR), distant metastasis rate (DMR) and overall survival (OS). We used a random-effects model or fixed-effects model for data pooling.

Results

Fifteen of the 424 eligible studies were ultimately included, and all studies were retrospective cohort studies (n=2532 participants). 1) SLRR: The SLRR of RBCS was higher than SM (pooled relative rate (pRR) = 1.87, 95% CI 1.22 - 2.86, P=0.004). Stratified analysis was performed according to whether radiotherapy was performed after salvage surgery (radiotherapy group: 2ndRT, no radiotherapy group: no-2ndRT), and the following results were revealed: pRR=0.43 (95% CI 0.20-0.95, P=0.04) for group 2ndRT; and pRR=2.30 (95% CI 1.72-3.06, P<0.00001) for group no-2ndRT. These results showed that the main cause of heterogeneity was salvage radiotherapy. 2) DMR: No significant difference in the DMR was observed between RBCS and SM (pRR = 0.61, 95% CI 0.37 - 1.01, P=0.05). 3) OS: No significant difference in OS was observed between RBCS and SM (pRR=0.65, 95% CI 0.39 - 1.08, P=0.10).

Conclusions

The SLRR of RBCS was higher than SM for ITBR after BCS, but survival was not affected. RBCS may be used as an alternative for IBTR patients after BCS with strict control for several indications, such as tumor size, recurrence interval and biological behavior, and attaching importance to subsequent salvage radiotherapy and systematic therapy.

How to Perform Repeat Sentinel Node Biopsy Safely After a Previous Mastectomy: Technical Features and Oncologic Outcomes

BACKGROUND

The latest National Comprehensive Cancer Network Breast Cancer Guidelines still discourage repeat sentinel node biopsy (SNB) after mastectomy, and the largest multicentric study available reports only 35 cases in the absence of previous axillary dissection (AD).

METHODS

From January 2003 to November 2018, 89 patients of the European Institute of Oncology with local recurrence of breast cancer after mastectomy, free of distant metastases, with a clinically negative axilla and a negative axillary ultrasound, in absence of AD, underwent lymphatic mapping before wide local excision.

RESULTS

During surgery, SNB was successful for 99% of the patients, with 14% being metastatic. Additional metastatic nodes removed by AD after a positive sentinel node occurred in 82% of cases. After a medium follow-up period of 3.7 years, the overall survival rate was 96.7%, and the disease-free survival rate was 84.4%. No axillary relapse after AD was recorded. One patient who refused human epidermal growth factor receptor 2 (HER2)-targeted treatment experienced ipsilateral axillary recurrence after a negative repeat SNB. The first axillary level was never directly irradiated because all the patients with positive repeat SNB underwent AD. For invasive luminal-like HER2-negative recurrences, the metastatic sentinel node was significantly associated with the choice to prescribe adjuvant chemotherapy (p = 0.003).

CONCLUSIONS

In specialized centers, repeat axillary SNB for patients with local recurrence after mastectomy in the absence of previous AD can represent a safe option for detection and removal of occult axillary disease that would otherwise not be excised/irradiated to achieve better local control and could possibly influence the choice of adjuvant treatments.

Proton reirradiation for recurrent or new primary breast cancer in the setting of prior breast irradiation

BACKGROUND AND PURPOSE

Late local recurrences and second primary breast cancers are increasingly common. Proton beam therapy (PBT) reirradiation (reRT) may allow safer delivery of a second definitive radiotherapy (RT) course. We analyzed outcomes of patients with recurrent or new primary breast cancer who underwent reRT.

MATERIALS AND METHODS

In an IRB-approved retrospective study, patient/tumor characteristics, treatment parameters, outcomes, and toxicities were collected for all consecutive patients with recurrent or new primary non-metastatic breast cancer previously treated with breast or chest wall RT who underwent PBT reRT.

RESULTS

Forty-six patients received reRT using uniform (70%) or pencil beam (30%) scanning PBT. Median first RT, reRT, and cumulative doses were 60 Gy (range 45-66 Gy), 50.4 Gy(RBE) (40-66.6 Gy(RBE)), and 110 Gy(RBE) (96.6-169.4 Gy(RBE)), respectively. Median follow-up was 21 months. There were no local or regional recurrences; 17% developed distant recurrence. Two-year DMFS and OS were 92.0% and 93.6%, respectively. Nine of 13 (69.2%) patients who underwent implant or flap reconstruction developed capsular contracture, 3 (23.1%) requiring surgical intervention. One (7.7%) patient developed grade 3 breast pain requiring mastectomy after breast conserving surgery. No acute or late grade 4-5 toxicities were seen. Increased body mass index (BMI) was protective of grade ≥ 2 acute toxicity (OR = 0.84, 95%CI = 0.70-1.00).

CONCLUSION

In the largest series to date of PBT reRT for breast cancer recurrence or new primary after prior definitive breast or chest wall RT, excellent locoregional control and few high-grade toxicities were encountered. PBT reRT may provide a relatively safe and highly effective salvage option. Additional patients and follow-up are needed to correlate composite normal tissue doses with toxicities and assess long-term outcomes.

Combined Therapy Can Improve the Outcomes of Breast Cancer with Isolated Supraclavicular Lymph Node Involvement

Purpose

This study aimed to evaluate the efficacy of systemic combined with local therapies in isolated metachronous ipsilateral supraclavicular lymph node metastasis (mISLM) breast cancer patients.

Patients and Methods

We reviewed the data of mISLM patients admitted by Breast Disease Center of the Affiliated Hospital of Qingdao University, from January 2009 to July 2019. Ninety-nine patients were included and were divided into two groups: the systemic group, which referred to patients who received only systemic therapy, and the combined group, which referred to patients who received systemic therapy plus local therapy (including neck radiotherapy (RT) and/or supraclavicular lymph node dissection surgery). In the combined group, patients were further divided into systemic therapy plus: 1) neck RT, 2) supraclavicular lymph node dissection surgery, and 3) neck RT and supraclavicular lymph node dissection surgery.

Results

The median duration of follow-up was 36 months. The median PFS was 15 months, and the median OS was 35 months. Local control rates of 1 year, 2 years and 3 years were 92.9%, 86.9% and 84.8%, respectively. The combined group (n=56) had a significantly better PFS (P<0.001) and OS (P=0.001) than the systemic group (n=43). Compared with Group B (n=13) and Group C (n=14), Group A (n=29) had a significantly better PFS (P=0.007). Higher dose and conventional dose showed no significant differences regarding the local control rate (P=1.000), PFS (P=0.787) or OS (P=0.690) in the patients who received RT. In multivariate analysis, pN3 stage and combined therapy (systemic therapy plus local therapy) for mISLM affected PFS (P<0.001 and P=0.002, respectively). Neck RT was an independent parameter affecting OS (P=0.002).

Conclusion

In breast cancer patients with mISLM, systemic therapy combined with local therapy could improve PFS and OS. Based on systemic therapy, RT had a better effect on survival than surgery. However, more aggressive methods, such as systemic therapy combined with both RT and surgery or a higher dose of RT, may not be associated with improved PFS or OS in these patients.

Locoregional Management of Inflammatory Breast Cancer

Purpose of Review

Inflammatory breast cancer (IBC) is a biologically aggressive subtype with a high risk for rapid local progression and early distant metastasis. We review the updated data for optimal locoregional management of IBC, including areas of active controversy.

Recent Findings

Advancements in tri-modality therapies have improved survival among IBC patients in recent years; however, the risk of locoregional and distant recurrence remains high, particularly in triple-negative IBC. Data to support de-escalation of surgery or radiotherapy is limited, and the recommended treatment approach for non-metastatic IBC remains preoperative systemic therapy (PST), modified radical mastectomy (MRM), and adjuvant radiotherapy in all patients. For patients with de novo metastatic disease, locoregional intervention may be appropriate.

Summary

Optimal locoregional management of IBC remains PST followed by MRM and adjuvant radiotherapy. With increasingly effective systemic therapies, research to identify a subset of patients who may benefit from de-escalation of locoregional therapies is warranted.

Shared decision making in breast cancer treatment guidelines: Development of a quality assessment tool and a systematic review

BACKGROUND

It is not clear whether clinical practice guidelines (CPGs) and consensus statements (CSs) are adequately promoting shared decision making (SDM).

OBJECTIVE

To evaluate the recommendations about SDM in CPGs and CSs concerning breast cancer (BC) treatment.

SEARCH STRATEGY

Following protocol registration (Prospero no.: CRD42018106643), CPGs and CSs on BC treatment were identified, without language restrictions, through systematic search of bibliographic databases (MEDLINE, EMBASE, Web of Science, Scopus, CDSR) and online sources (12 guideline databases and 51 professional society websites) from January 2010 to December 2019.

INCLUSION CRITERIA

CPGs and CSs on BC treatment were selected whether published in a journal or in an online document.

DATA EXTRACTION AND SYNTHESIS

A 31-item SDM quality assessment tool was developed and used to extract data in duplicate.

MAIN RESULTS

There were 167 relevant CPGs (139) and CSs (28); SDM was reported in only 40% of the studies. SDM was reported more often in recent publications after 2015 (42/101 (41.6 %) vs 46/66 (69.7 %), P = .0003) but less often in medical journal publications (44/101 (43.5 %) vs 17/66 (25.7 %), P = .009). In CPGs and CSs with SDM, only 8/66 (12%) met one-fifth (6 of 31) of the quality items; only 14/66 (8%) provided clear and precise SDM recommendations.

DISCUSSION AND CONCLUSIONS

SDM descriptions and recommendations in CPGs and CSs concerning BC treatment need improvement. SDM was more frequently reported in CPGs and CSs in recent years, but surprisingly it was less often covered in medical journals, a feature that needs attention.

Prognosis of Surgical Treatment After Ipsilateral Breast Tumor Recurrence

BACKGROUND

Ipsilateral breast tumor recurrence (IBTR) was determined to be a powerful independent risk factor of distant disease and increased mortality. Although mastectomy is the standard salvage treatment for IBTR after breast conserving treatment, there is evidence that repeat breast conserving surgery (rBCS) might be a feasible alternative treatment.

MATERIALS AND METHODS

The data of patients who were diagnosed with IBTR between 1998 and 2013 were obtained from the Surveillance, Epidemiology, and End Results database. Breast cancer-specific survival (BCSS) and overall survival (OS) were calculated using the Kaplan-Meier method. The Cox proportional hazards model was used for multivariate analysis, and propensity score matching analysis was applied to compensate for the differences in some baseline characteristics.

RESULTS

A total of 475 patients (22.9%) who underwent rBCS and 1600 (77.1%) who underwent mastectomy after IBTR were included in the study. During a median follow-up of 130 mo, no significant differences were observed in BCSS and OS between the rBCS and mastectomy groups of patients before and after propensity score matching. Multivariate analysis revealed that race, the American Joint Committee on Cancer stage of the recurrent tumor, and reirradiation were independent prognostic factors for both BCSS and OS.

CONCLUSIONS

The results of our study indicate that rBCS can be a feasible alternative treatment option for patients with IBTR. Nevertheless, further studies should be conducted to identify the prognosis of patients after rBCS as well as the best candidates for a second breast conserving surgery.

Identifying Long-Term Survival Candidates among Patients with Isolated Locoregionally Recurrent Breast Cancer: Implications of the Use of Systemic Chemotherapy

Purpose

We aimed to investigate the clinicopathologic factors associated with distant metastasis (DM) and post-recurrence overall survival (OS) after salvage treatments for isolated locoregional recurrence (ILRR) of breast cancer and identify long-term surviving patients for providing a more personalized therapy.

Methods

We analyzed 125 patients who underwent salvage local treatments for ILRR after initial curative breast surgery.

Results

Fifty-two (41.6%) patients experienced secondary recurrence or disease progression, of which 20 (38.5%) experienced a secondary locoregional recurrence and 40 (76.9%) experienced DM as the first site of failure. In multivariate analysis of distant metastasis free survival (DMFS) and post-recurrence OS, the initial pN2-3 stage, a disease-free interval of < 36 months, and non-curative resection for recurrent disease were independently poor prognosticators. The score for patients stratified according to the number of risk factors increased from 0 to 3; the corresponding 5-year DMFS rates were 91.4%, 53.0%, 35.9%, and 0% and the 5-year OS rates were 97.3%, 70.4%, 32.7%, and 25.0%, respectively (p < 0.001). Systemic chemotherapy reduced DM in patients with a score of 2-3, but it did not in those with a score of 0-1.

Conclusion

Our collective stratification can help with prognosis prediction for ILRR of breast cancer. Depending on the DM risk of patients, the potential combination of systemic therapy should be discussed further.

Integrating Loco-Regional Hyperthermia Into the Current Oncology Practice: SWOT and TOWS Analyses

Moderate hyperthermia at temperatures between 40 and 44°C is a multifaceted therapeutic modality. It is a potent radiosensitizer, interacts favorably with a host of chemotherapeutic agents, and, in combination with radiotherapy, enforces immunomodulation akin to “in situ tumor vaccination.” By sensitizing hypoxic tumor cells and inhibiting repair of radiotherapy-induced DNA damage, the properties of hyperthermia delivered together with photons might provide a tumor-selective therapeutic advantage analogous to high linear energy transfer (LET) neutrons, but with less normal tissue toxicity. Furthermore, the high LET attributes of hyperthermia thermoradiobiologically are likely to enhance low LET protons; thus, proton thermoradiotherapy would mimic ¹²C ion therapy. Hyperthermia with radiotherapy and/or chemotherapy substantially improves therapeutic outcomes without enhancing normal tissue morbidities, yielding level I evidence reported in several randomized clinical trials, systematic reviews, and meta-analyses for various tumor sites. Technological advancements in hyperthermia delivery, advancements in hyperthermia treatment planning, online invasive and non-invasive MR-guided thermometry, and adherence to quality assurance guidelines have ensured safe and effective delivery of hyperthermia to the target region. Novel biological modeling permits integration of hyperthermia and radiotherapy treatment plans. Further, hyperthermia along with immune checkpoint inhibitors and DNA damage repair inhibitors could further augment the therapeutic efficacy resulting in synthetic lethality. Additionally, hyperthermia induced by magnetic nanoparticles coupled to selective payloads, namely, tumor-specific radiotheranostics (for both tumor imaging and radionuclide therapy), chemotherapeutic drugs, immunotherapeutic agents, and gene silencing, could provide a comprehensive tumor-specific theranostic modality akin to “magic (nano)bullets.” To get a realistic overview of the strength (S), weakness (W), opportunities (O), and threats (T) of hyperthermia, a SWOT analysis has been undertaken. Additionally, a TOWS analysis categorizes future strategies to facilitate further integration of hyperthermia with the current treatment modalities. These could gainfully accomplish a safe, versatile, and cost-effective enhancement of the existing therapeutic armamentarium to improve outcomes in clinical oncology.

High-dose-rate Brachytherapy as Adjuvant Local rEirradiation for Salvage Treatment of Recurrent breAst cancer (BALESTRA): a retrospective mono-institutional study

PURPOSE

To evaluate clinical results of catheter-based interstitial high-dose-rate (HDR) brachytherapy (BT) as adjuvant treatment in previously irradiated recurrent breast cancer.

MATERIAL AND METHODS

Between January 2011 and September 2015, 31 consecutive patients with histologically confirmed recurrent breast cancer after conservative surgery and conventional whole breast radiotherapy, were retreated with a second conservative surgical resection and reirradiated with adjuvant interstitial HDR-BT. None of the brachytherapy implant was performed during the quadrantectomy procedure. A dose of 34 Gy in 10 fractions, 2 fractions per day, with a minimal interval of 6 hours was delivered.

RESULTS

At the time of the implant, the median age of patients was 59.7 years (range, 39.3-74.9 years). The median time from first treatment until BT for local recurrence was 11.9 years (range, 2.5-27.8 years). The median interval between salvage surgery and BT was 3.6 months (range, 1-8.2 months). No acute epidermitis or soft tissue side effects higher than grade 2 were recorded, with good cosmetic results in all patients. Most of the patients presented grade 1-2 late side effects. Only one patient developed grade 3 liponecrosis. After a median follow-up of 73.7 months (range, 28.8-102.4 months), the overall survival and cancer specific survival were 87.1% and 90.3%, respectively; 5-year local control and 5-year progression-free survival rate were 90.3% and 83.9%, respectively.

CONCLUSIONS

Our preliminary analysis showed that HDR-BT is a feasible treatment for partial breast reirradiation offering very low complications rate and fast procedure. Higher patients' cohort is warranted in order to define the role of this treatment modality in the breast conservative management of local recurrence.

Breast-conserving surgery with intraoperative radiotherapy in recurrent breast cancer: the patient's perspective

Purpose

When ipsilateral breast-tumor recurrence (IBTR) following breast-conserving surgery (BCS) occurs, the cure of a potentially life-threatening disease is the main goal. If, however, this is diagnosed early, prognosis is still good and patient-reported outcomes become more important. Despite the fact that many patients would prefer a further BCS, international breast cancer guidelines still recommend mastectomy, mainly because previous radiation implies limited options. Our comparative study evaluates the long-term quality-of-life and outcome in patients with IBTR who received BCS plus intraoperative radiotherapy (IORT) versus mastectomy.

Methods

Patients with IBTR were retrospectively divided into three groups according to the local treatment: group 1 (n = 26) was treated with BCS + IORT; group 2 (n = 35) received a standard mastectomy; group 3 (n = 52) had a mastectomy with subsequent reconstruction. Outcomes were analyzed after a mean follow-up of 5 years after IBTR. Quality-of-life was evaluated by the validated questionnaire BREAST-Q in 50 patients who fulfilled the inclusion criteria.

Results

Quality-of-life scores varied within the groups, ranging from 51.4 to 91.3 (out of 100 points). We observed satisfactory scores in all items, with no statistical difference within the groups. Disease-free survival of all groups did not statistically differ, and overall mortality was very low (0.9%). The postinterventional complication rate was lower after BCS (19.2% versus 34.3% after mastectomy and 30.8% after mastectomy with reconstruction).

Conclusion

For patients with previous surgery and radiation who demand a second BCS in the recurrent situation, this surgical technique can be offered in combination with IORT. Our long-term results imply oncological safety, lower complication rate, and good patient satisfaction.

Differences of the Immune Phenotype of Breast Cancer Cells after Ex Vivo Hyperthermia by Warm-Water or Microwave Radiation in a Closed-Loop System Alone or in Combination with Radiotherapy

The treatment of breast cancer by radiotherapy can be complemented by hyperthermia. Little is known about how the immune phenotype of tumor cells is changed thereby, also in terms of a dependence on the heating method. We developed a sterile closed-loop system, using either a warm-water bath or a microwave at 2.45 GHz to examine the impact of ex vivo hyperthermia on cell death, the release of HSP70, and the expression of immune checkpoint molecules (ICMs) on MCF-7 and MDA-MB-231 breast cancer cells by multicolor flow cytometry and ELISA. Heating was performed between 39 and 44 °C. Numerical process simulations identified temperature distributions. Additionally, irradiation with 2 × 5 Gy or 5 × 2 Gy was applied. We observed a release of HSP70 after hyperthermia at all examined temperatures and independently of the heating method, but microwave heating was more effective in cell killing, and microwave heating with and without radiotherapy increased subsequent HSP70 concentrations. Adding hyperthermia to radiotherapy, dynamically or individually, affected the expression of the ICM PD-L1, PD-L2, HVEM, ICOS-L, CD137-L, OX40-L, CD27-L, and EGFR on breast cancer cells. Well-characterized pre-clinical heating systems are mandatory to screen the immune phenotype of tumor cells in clinically relevant settings to define immune matrices for therapy adaption.

Second conservative treatment for second ipsilateral breast tumor event: A systematic review of the different re-irradiation techniques

AIM

To address the different partial breast re-irradiation techniques available in the context of second conservative treatment (SCT), as an alternative to salvage mastectomy, for 2nd ipsilateral breast tumor event (IBTE) and summarize their respective oncological and toxicity outcomes.

MATERIAL AND METHODS

A literature search was made based on MeSH/PubMed, including papers from 1995 to 2019. Each article was described according to the main irradiation technique, fractionation, oncological results and grade 3 toxicities related to the salvage conservative treatment.

RESULTS

Twenty-two articles were identified, reporting the outcomes of over 1 000 patients. MIB Brachytherapy was the most used re-irradiation technique in case of SCT, with a median 3rdIBTE-FS rate of 88% and summed up grade 3 toxicities of 6%. As for IORT, the average rate of 3rdIBTE-FS was about Finally, external beam partial re-irradiation was recently tested in this indication with encouraging results in terms of tolerance.

CONCLUSION

When presenting a 2ndIBTE, a SCT can safely be proposed to carefully selected and well-informed patients, as an alternative to salvage mastectomy. MIB appears to be the first intention and most robust choice. IORT, external beam radiotherapy and balloon brachytherapy are interesting alternatives but have only been tested in small series. Further investigations are required and their use should be limited to clinical trial only.

Suppression of the proliferation and invasion of breast cancer cells by ST7L occurs through inhibition of activation of Wnt/GSK-3β/β-catenin signalling

Emerging evidence has indicated that suppression of tumorigenicity 7-like (ST7L) is a tumour suppressor in multiple types of cancers. However, the functional involvement of ST7L has not been studied in breast cancer. In the present study, we aimed to investigate the potential biological function of ST7L in breast cancer. Herein, we found that ST7L expression was frequently downregulated in breast cancer cell lines. Functional assays revealed that ST7L overexpression significantly inhibited the proliferation and invasion of breast cancer cells, while ST7L silencing showed opposite effect. Notably, ST7L was found to decrease glycogen synthase kinase (GSK)-3β phosphorylation and downregulate active β-catenin protein expression, thereby leading to repression of β-catenin transcriptional activity. Activation of Wnt/β-catenin signalling by treatment of GSK-3β inhibitor significantly abrogated ST7L-mediated antitumour effect. Additionally, ST7L overexpression blunted the tumorigenicity of breast cancer cells in vivo in xenograft mice. Taken together, our results demonstrate that ST7L exerts antitumor function in breast cancer associated with the suppression of Wnt/β-catenin signalling, suggesting ST7L as a potential therapeutic target for breast cancer.

Second breast conserving therapy after ipsilateral breast tumor recurrence - a 10-year experience of re-irradiation

Purpose

The aim of this study is to evaluate the efficacy and toxicity of post-operative partial breast re-irradiation with multi-catheter brachytherapy after second breast conserving therapy (BCT) in patients with small, low-risk ipsilateral breast tumor recurrence (IBTR).

Material and methods

Between 2008 and 2018, 19 consecutive patients with low-risk IBTR (max. rpT1 cN0 cM0, Her2 negative, preferably positive hormone receptor status) who refused mastectomy were treated with salvage lumpectomy, followed by post-operative partial breast re-irradiation with multi-catheter brachytherapy. Eight patients were irradiated using PDR brachytherapy (49.8-50.4 Gy in pulses of 0.5-0.7 Gy) and 11 patients using HDR brachytherapy (34.2 Gy in fractions of 3.8 Gy or 32 Gy in fractions of 4 Gy). All patients had undergone prior BCT for their primary tumor, followed by adjuvant whole breast radiotherapy. Local control (LC), locoregional control (LRC), overall survival (OS), disease-free survival (DFS) as well as toxicity were evaluated in the present study.

Results

After a median follow-up of 65 months following IBTR (18-120 months), only one second IBTR in 19 patients was diagnosed 77 months after re-irradiation, resulting in a LC rate of 100% at 5 years. DFS and OS rates were both 100% at 5 years following re-irradiation. Except for the above mentioned second IBTR, no regional or distant relapse was recorded. Regarding toxicity, 63% of patients developed adverse events (CTCAE grade ≤ 2), with fibrosis detected in 37% (7/19) of patients, necrosis in 11% (2/19), hyperpigmentation in 47% (9/19), and telangiectasia in 11% (2/19), respectively. No patient showed a high-grade (CTCAE grade ≥ 3) adverse event.

Conclusions

In case of small, low-risk IBTR, adjuvant re-irradiation using multi-catheter brachytherapy is a feasible, safe, and effective treatment method after repeated lumpectomy, and an alternative to mastectomy.

Reirradiation of recurrent breast cancer with proton beam therapy: A case report and literature review

BACKGROUND

Locoregional recurrence of breast cancer is challenging for clinicians, due to the various former treatments patients have undergone. However, treatment of the recurrence with systemic therapy and subsequent reirradiation of chest wall is accompanied by increased toxicities, particularly radiation-induced cardiovascular disease. Reirradiation by proton beam therapy (PBT) enables superior preservation of adjacent organs at risk as well as concurrent dose escalation for delivery to the gross tumor. This technology is expected to improve the overall outcome of recurrent breast cancer.

CASE SUMMARY

A 47-year-old female presented with an extensive locoregional recurrence at 10 yr after primary treatment of a luminal A breast cancer. Because of tumor progression despite having undergone bilateral ovarectomy and systemic therapy, the patient was treated with PBT BE total dose of 64.40 Gy to each gross tumor and 56.00 Gy to the upper mediastinal and retrosternal lymphatics including the entire sternum in 28 fractions. Follow-up computed tomography showed a partial remission, without evidence of newly emerging metastasis. At 19 mo after the PBT, the patient developed a radiation-induced pericardial disease and pleural effusions with clinical burden of dyspnea, which were successfully treated by drainage and corticosteroid. Cytological analysis of the puncture fluid showed no malignancy, and the subsequent computed tomography scan indicated stable disease as well as significantly decreased pericardial and pleural effusions. The patient remains free of progression to date.

CONCLUSION

PBT was a safe and effective method of reirradiation for locoregionally recurrent breast cancer in our patient.

Prospective results of concurrent radiation therapy and weekly paclitaxel as salvage therapy for unresectable locoregionally recurrent breast cancer

Purpose

To investigate the efficacy and toxicity of concurrent radiation therapy (RT) and paclitaxel in the treatment of unresectable locoregionally recurrent breast cancer (RBC) after mastectomy as primary treatment.

Methods

This was a prospective monocentric study of 51 patients (pts) diagnosed with unresectable locoregionally RBC after mastectomy and treated between 2008 and 2012. Radiotherapy (RT) was delivered at 60 Gy in 30 treatment fractions to recurrent sites. Chemotherapy was weekly paclitaxel of 50 mg/m² for 5 weeks. All pts. underwent clinical examination, CT or PET/CT every 3 months in first 2 years and then every 6 months. Tumor response was evaluated clinically and by CT using the RECIST criteria. Toxicity was assessed weekly during RT by the NCI common toxicity criteria (version 3.0).

Results

Fifty-one pts. with 61 recurrent sites were studied. The median age was 49 years. Sites of RBC were chest wall in 20 patients (32.8%), supraclavicular in 19 (31.1%), axilla in 11 (18.0%), and internal mammary lymph nodes in the remaining 11 (18.0%). RBC presented as single in 25 pts., multiple in 20 pts. and diffuse growth in 6 pts. Clinical response was observed in 47 pts. (92.2%), with 36 (70.6%) complete and 11 (21.6%) partial responses. Two patients (3.9%) presented with stable disease and 2 progressive disease. The cumulative local progression-free survival rate was 62.8% at 2 year and 53.0% at 5 years after treatment. No grade 4 toxicity was observed. Grade 3 radiation dermatitis and leukocytopenia were observed in 10 (19.6%) and 12 (23.5%) pts., respectively. One patient experienced grade 2 pneumonitis.

Conclusions

Concurrent RT and weekly paclitaxel could be an effective therapeutic option for unresectable locoregionally recurrent breast cancer after mastectomy with an acceptable toxicity profile.

Salvage treatment with sole high-dose-rate endobronchial interventional radiotherapy (brachytherapy) for isolated endobronchial tumor recurrence in non-small-cell lung cancer patients: a 20-year experience

PURPOSE

The purpose of this study was to report on the use of high-dose-rate (HDR) endobronchial interventional radiotherapy (brachytherapy) for isolated endobronchial tumor recurrence in patients with non-small-cell lung cancer, in whom a surgery or external radiation treatment is not possible.

METHODS AND MATERIALS

A retrospective review of the patients with endobronchial tumors treated with HDR-endobronchial interventional radiotherapy at our institution (1995-2015) was performed. Treatment results and treatment-related toxicity were recorded. Clinical response was evaluated by bronchoscopy 3 months after treatment. Disease-free survival and overall survival were analyzed.

RESULTS

One hundred twenty-six patients were identified. The median age was 63 years, and median followup time was 67.2 months. Three-month complete local response was 86.5%. At 5 years, disease-free survival was 41.4% and overall survival was 23.6%. 12.7% of the patients died from massive hemoptysis.

CONCLUSION

HDR-endo brochial brachytherapy is an effective treatment option with acceptable toxicity for patients with endobronchial tumor recurrence in whom surgery and external beam radiotherapy are contraindicated.

A microfluidic assay for the quantification of the metastatic propensity of breast cancer specimens

The challenge of predicting which patients with breast cancer will develop metastases leads to the overtreatment of patients with benign disease and to the inadequate treatment of the aggressive cancers. Here, we report the development and testing of a microfluidic assay that quantifies the abundance and proliferative index of migratory cells in breast-cancer specimens, for the assessment of their metastatic propensity and for the rapid screening of potential antimetastatic therapeutics. On the basis of the key roles of cell motility and proliferation in cancer metastasis, the device accurately predicts the metastatic potential of breast-cancer cell lines and of patient-derived xenografts. Compared to unsorted cancer cells, highly motile cells isolated by the device exhibited similar tumourigenic potential but markedly increased metastatic propensity in vivo. RNA sequencing of the highly motile cells revealed an enrichment of motility-related and survival-related genes. The approach might be developed into a companion assay for the prediction of metastasis in patients and for the selection of effective therapeutic regimens.

microRNAs-107 inhibited autophagy, proliferation, and migration of breast cancer cells by targeting HMGB1

PURPOSE

To investigate the effects of microRNAs-107 (miR-107) on autophagy, proliferation, and migration of breast cancer cells and its mechanism by targeting high mobility group protein B1 (HMGB1).

METHODS

Real-time polymerase chain reaction assay was used to detect the expression of miR-107 in breast cancer and its cell lines. In MDA-MB-231 and MDA-MB-453 breast cancer cells, the expression of p62, Beclin1 protein, and the changes of cell proliferation and migration after overexpression of m miR-107 were detected by Western blotting, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, and transwell assays. Target Scan online prediction, dual luciferase reporter gene, and Western blot were used to verify the targeting relationship between miR-107 and HMGB1. The effects of silencing HMGB1 expression on p62, Beclin1 protein expression, cell proliferation, and migration ability were detected. The transfected MDA-MB-453 cells were inoculated into the right axilla of the nude mice, the tumor volume and weight were weighed, and the expression of miR-107, HMGB1, p62, and Beclin1 in the tumor were detected.

RESULTS

The expression of miR-107 was downregulated in breast cancer tissues and cell lines (P < 0.01). The expression of p62 protein was upregulated (P < 0.01), while Beclin1 protein was downregulated (P < 0.01) and cell proliferation and migration ability were decreased (P < 0.01) after overexpressing miR-107 in MDA-MB-231 and MDA-MB-453 cells. The results of TargetScan online prediction, dual luciferase reporter gene, and Western blot showed that miR-107 could regulate HMGB1 expression. The expression of p62 protein was upregulated (P < 0.01), while Beclin1 protein was downregulated (P < 0.01) and cell proliferation and migration ability were decreased (P < 0.01) after silencing HMGB1 in MDA-MB-231 and MDA-MB-453 cells. The results of xenograft experiments showed that miR-107 could delay tumor growth and inhibit autophagy.

CONCLUSION

miR-107 could inhibit cell autophagy, proliferation, and migration of breast cancer cells by targeting HMGB1.

Second breast-conserving surgery and interstitial brachytherapy vs. salvage mastectomy for the treatment of local recurrences: 5-year results

PURPOSE

The purpose of this study was to report the clinical outcomes of a second breast-conserving therapy (2nd BCT) with perioperative interstitial brachytherapy (iBT) vs. those of salvage mastectomy (sMT) in the treatment of ipsilateral breast tumor recurrences (IBTRs).

METHODS AND MATERIALS

Between 1999 and 2015, 195 patients with IBTR after a previous breast-conserving treatment were salvaged either with reexcision and perioperative high-dose-rate iBT (n = 39), or with sMT (n = 156). In the 2nd BCT group, a total dose of 22 Gy in five fractions of 4.4 Gy was delivered to the tumor bed with intraoperatively implanted catheters for 3 consecutive days.

RESULTS

The median followup time was 59 months (1-189) in the 2nd BCT, and 56 months (3-189) in the sMT group. The mean size of IBTR was 16 mm (2-70) vs. 24 mm (2-90), respectively (p = 0.0005), but there were no other significant differences in patient- or IBTR-related parameters between the two groups. During the followup period, 4 of 39 (10.2%) and 28 of 156 (17.9%) second local recurrences (2nd LR) occurred in the 2nd BCT and the sMT group, respectively. The 5-year actuarial rate of 2nd LR was 6% vs. 18% (p = 0.22), the 5-year probability of disease-free, cancer-specific and overall survival was 69% vs. 65% (p = 0.13), 85% vs. 78% (p = 0.32), and 81% vs. 66% (p = 0.15), respectively. In the 2nd BCT group, the rate of good to excellent cosmesis was 70%.

CONCLUSIONS

2nd BCT with perioperative high-dose-rate iBT is a safe and feasible option for the management of IBTR, resulting in similar 5-year oncological outcomes and better cosmetic results compared with sMT.

Increased Mortality with Repeat Lumpectomy Alone After Ipsilateral Breast Tumor Recurrence

BACKGROUND

The benefit of repeat lumpectomy for ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery is currently inconclusive.

MATERIALS AND METHODS

Patients with IBTR with definitive surgery were identified in the Surveillance, Epidemiology, and End Results registry between 1973 and 2013. The effect of different IBTR surgeries on overall and cancer-specific mortality was assessed using risk-adjusted Cox proportional hazard regression modeling and stratified propensity score-matching analysis (PSMA).

RESULTS

Of the 5,098 patients with IBTR, 4,048 (79.4%) women underwent mastectomy and 1,050 (20.1%) underwent repeat lumpectomy. In multivariable Cox regression analysis, repeat lumpectomy was associated with increased overall mortality (hazard ratio for death [HR], 1.522; 95% confidence interval [CI], 1.317-1.759; p < .001) and cancer-specific mortality (HR, 1.666; 95% CI, 1.319-2.105; p < .001). Similar HRs were derived from the PSMA cohort. However, we found no significant difference in overall mortality for women who underwent repeat lumpectomy followed by radiation therapy (RT) compared with that for those who underwent mastectomy. Moreover, patients with IBTR with small tumors (≤1 cm) who underwent repeat lumpectomy with RT rather than without had similar overall and cancer-specific survival rates to those who underwent mastectomy.

CONCLUSION

Our investigation suggests that compared with mastectomy, repeat lumpectomy for IBTR is associated with higher overall and cancer-specific mortality under real-world observational conditions. Furthermore, repeat lumpectomy with RT is equivalent to mastectomy with respect to overall mortality and may influence treatment decision making for patients with small IBTR.

IMPLICATIONS FOR PRACTICE

Although mastectomy has been regarded as the standard treatment for ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery, many patients diagnosed with small and early-detected recurrent tumor might be technically suitable for a less invasive surgical procedure. However, different studies have drawn inconsistent conclusions. The present study is a population-based analysis, which demonstrated the overall unfavorable impact of repeat lumpectomy over mastectomy on survival outcomes for patients with IBTR. However, patients with small IBTR (≤1 cm) that can tolerate radiation therapy may be the optimal candidates for repeat lumpectomy.