Neoadjuvant radiotherapy of early-stage breast cancer and long-term disease-free survival

Concurrent Neoadjuvant Chemotherapy and Radiation in Locally Advanced Breast Cancer: Impact on Locoregional Recurrence Rates

Neoadjuvant chemoradiation therapy (NCRT) is an underutilized treatment in breast cancer but may improve outcomes by impacting the tumor immune microenvironment. The aim of this study was to evaluate NCRT's impact on recurrence and the role of tumor-infiltrating lymphocytes (TILs) in treatment response. We hypothesized that NCRT reduces recurrence by upregulating TILs. Patients with locally advanced breast cancer (LABC) were treated with NCRT. Stage IIB to III patients with any molecular subtypes were eligible. The patients were matched for age, stage, and molecular subtype by a propensity score to a concurrent cohort receiving standard neoadjuvant chemotherapy (NCT) followed by adjuvant radiation. The objective of this study was to assess the patients in terms of the pathological complete response (pCR), TIL counts prior to and following treatment, and locoregional recurrence. The median follow-up was 7.2 years. Thirty NCRT patients were successfully matched 1:3 to ninety NCT patients. The NCRT cohort had no regional and locoregional recurrences (p = 0.036, (hazard ratio) HR [0.25], 95% confidence interval (CI) [0.06-0.94] and p = 0.013, HR [0.25], 95% CI [0.08-0.76], respectively), compared to 17.8% of the NCT cohort. The NCRT group had significantly more pCRs, and TILs were increased in the post-treatment pCR specimens. NCRT can improve outcomes in LABC patients, with a higher pCR and significantly lower locoregional recurrence/higher recurrence-free survival. Further trials are needed to evaluate the role of NCRT in all breast cancer patients.

The Impact of Synchrotron Microbeam Radiation Therapy Combined With Broad Beam in a Preclinical Breast Cancer Model

Purpose

Both local tumor control and distant metastasis are important indicators of the efficacy of radiation therapy treatment. Synchrotron microbeam radiation therapy (MRT), spatially fractionated radiation delivered at ultrahigh dose rates, shows remarkable normal tissue sparing with excellent local control in some models. Some MRT regimens trigger an antitumor immune response that contributes not only to the local but also to systemic treatment efficacy. Despite recent advances in the treatment of primary breast cancer, metastatic disease is still the major cause of treatment failure in the clinic. Here, in an aggressive preclinical triple-negative breast cancer model, we compared local tumor response and metastasis following different MRT treatment programs.

Methods and Materials

4T1.2 mouse mammary tumors were treated with 300 Gy peak/7 Gy valley dose MRT and/or 8 Gy broad beam (BB) radiation, all delivered as daily fractionated programs (3 consecutive daily sessions of either MRT or BB or 1 MRT combined with 2 BB sessions, the first or last of the 3 fractions). The mice were euthanized on day 9 post last irradiation, when unirradiated control animals reached an ethical endpoint. Primary tumors were collected to evaluate immune cell prevalence, while lungs, spinal cords, and locoregional lymph nodes were collected to measure metastatic burden. In parallel, local tumor growth and survival were monitored.

Results

The combined MRT/BB treatment shifted the balance between pro- and antitumorigenic macrophages toward the accumulation of antitumorigenic macrophages in the tumor. Monitoring of the tumor volume and animal health indicated the benefit of the combined MRT/BB treatment for local control and treatment tolerance, while animal survival was only marginally longer for one combined schedule. The metastatic burden was similar for all 4 treatment schedules.

Conclusions

The addition of a single MRT to BB treatment improved the primary tumor response. This provides a basis for future experiments incorporating adjuvant immunotherapy or chemotherapy to improve local and systemic treatment outcomes.

Research hotspots and frontiers of neoadjuvant therapy in triple-negative breast cancer: a bibliometric analysis of publications between 2002 and 2023

Triple-negative breast cancer (TNBC) is a highly aggressive type of breast cancer with poor prognosis, and neoadjuvant therapy (NAT) has emerged as an important component in managing advanced-stage patients by providing surgical opportunities and improving survival outcomes. A search of publications on NAT for TNBC from 2002 to 2023 was conducted through the Web of Science core collection. A comprehensive bibliometric analysis was conducted on the data using CiteSpace, VOSviewer, and Bibliometrix. The analysis revealed a continuous and steady growth in the number of articles published in this field over the past 20 years. The United States has made significant contributions to this field, with The University of Texas MD Anderson Cancer Center publishing the most articles. Loibl, S. from Germany was found to be the most published author with 54 articles. Analysis of the journals showed that the Journal of Clinical Oncology is the most cited journal. Combined with the keyword co-occurrence analysis and clustering analysis, current research topic focuses on treatment regimens and disease prognosis. Dual-map overlay of the journals indicates that the research trend is gradually shifting from molecular biology and genetics to immunology and clinical research. Combination therapy, including immunotherapy, may be the future direction for NAT treatment of TNBC. Overall, this study provides valuable insights into the current research status, latest advancements, and emerging development trend of NAT for TNBC.

Neoadjuvant radiochemotherapy is safe and feasible for breast conserving surgery or immediate reconstruction

This study aimed to evaluate the survival outcomes of neoadjuvant radiochemotherapy (NARCT) for early breast cancer. Female patients ≤ 80 years old with unilateral T1-T4 invasive ductal breast cancer treated with neoadjuvant chemotherapy (NAC) and radiation therapy (RT) between 2006 and 2015 were enrolled from SEER database. Baseline differences in clinical and pathological characteristics were evaluated using chi-square test. The survival outcomes were estimated by Kaplan-Meier analysis and compared using Cox hazards models. The effects of baseline differences on survival outcome in patients treated with neoadjuvant radiation therapy (NART) and post-operation radiation therapy (PORT) were circumvented by propensity score matching (PSM). Altogether 14,151 patients receiving NAC and RT were enrolled, among whom 386 underwent NART. Based on a 1:4 PSM cohort, NART was an independent unfavorable prognostic factor for breast cancer-specific survival (BCSS) and overall survival (OS) for the whole cohort. However, among patients receiving breast conserving surgery (BCS) (HR 1.029, P = 0.915 for BCSS; HR 1.003, P = 0.990 for OS) or implant-based immediate breast reconstruction (IBR) (HR 1.039, P = 0.921 for BCSS; HR 1.153, P = 0.697 for OS), those treated with NART had similar survival outcomes compared with patients treated with PORT. In conclusion, NARCT was a safe and feasible approach for patients undergoing BCS and IBR.

Implantable, 3D-Printed Alginate Scaffolds with Bismuth Sulfide Nanoparticles for the Treatment of Local Breast Cancer via Enhanced Radiotherapy

Surgical removal of tumor tissue remains the primary clinical approach for addressing breast cancer; however, complete tumor excision is challenging, and the remaining tumor cells can lead to tumor recurrence and metastasis over time, which substantially deteriorates the life quality of the patients. With the aim to improve local cancer radiotherapy, this work reports the fabrication of alginate (Alg) scaffolds containing bovine serum albumin (BSA)-coated bismuth sulfide (Bi2S3@BSA) nanoradiosensitizers using three-dimensional (3D) printing. Under single-dose X-ray irradiation in vitro, Alg-Bi2S3@BSA scaffolds significantly increase the formation of reactive oxygen species, enhance the inhibition of breast cancer cells, and suppress their colony formation capacity. In addition, scaffolds implanted under tumor tissue in murine model show high therapeutic efficacy by reducing the tumor volume growth rate under single-dose X-ray irradiation, while histological observation of main organs reveals no cytotoxicity or side effects. 3D-printed Alg-Bi2S3@BSA scaffolds produced with biocompatible and biodegradable materials may potentially lower the recurrence and metastasis rates in breast cancer patients by inhibiting residual tumor cells following postsurgery as well as exhibit anticancer properties in other solid tumors.

Txnrd1 as a prognosticator for recurrence, metastasis and response to neoadjuvant chemotherapy and radiotherapy in breast cancer patients

Thioredoxin reductase 1 (Txnrd1) is known to have prognostic significance in a subset of breast cancer patients. Despite the pivotal role of Txnrd1 in regulating several cellular and physiological processes in cancer progression and metastasis, its clinical significance is largely unrecognized. Here, we undertook a retrospective comprehensive meta-analysis of 13,322 breast cancer patients from 43 independent cohorts to assess prognostic and predictive roles of Txnrd1. We observed that Txnrd1 has a positive correlation with tumor grade and size and it is over-expressed in higher-grade and larger tumors. Further, hormone receptor-negative and HER2-positive tumors exhibit elevated Txnrd1 gene expression. Patients with elevated Txnrd1 expression exhibit significant hazards for shorter disease-specific and overall survival. While Txnrd1 has a positive correlation with tumor recurrence and metastasis, it has a negative correlation with time to recurrence and metastasis. Txnrd1High patients exhibit 2.5 years early recurrence and 1.3 years early metastasis as compared to Txnrd1Low cohort. Interestingly, patients with high Txnrd1 gene expression exhibit a pathologic complete response (pCR) to neoadjuvant chemotherapy, but they experience early recurrence after radiotherapy. Txnrd1High MDA-MB-231 cells exhibit significant ROS generation and reduced viability after doxorubicin treatment compared to Txnrd1Low MCF7 cells. Corroborating with findings from meta-analysis, Txnrd1 depletion leads to decreased survival, enhanced sensitivity to radiation induced killing, poor scratch-wound healing, and reduced invasion potential in MDA-MB-231 cells. Thus, Txnrd1 appears to be a potential predictor of recurrence, metastasis and therapy response in breast cancer patients.

Antineoplastic effect of compounds C14 and P8 on TNBC and radioresistant TNBC cells by stabilizing the K-Ras4BG13D/PDE6δ complex

Introduction

Breast cancer (BC) is the leading cause of cancer-related deaths among women, with triple-negative breast cancer (TNBC) representing one of the most aggressive and treatment-resistant subtypes. In this study, we aimed to evaluate the antitumor potential of C14 and P8 molecules in both TNBC and radioresistant TNBC cells. These compounds were chosen for their ability to stabilize the complex formed by the overactivated form of K-Ras4BG13D and its membrane transporter (PDE6δ).

Methods

The antitumor potential of C14 and P8 was assessed using TNBC cell lines, MDA-MB-231, and the radioresistant derivative MDA-MB-231RR, both carrying the K-Ras4B> G13D mutation. We investigated the compounds' effects on K-Ras signaling pathways, cell viability, and tumor growth in vivo.

Results

Western blotting analysis determined the negative impact of C14 and P8 on the activation of mutant K-Ras signaling pathways in MDA-MB-231 and MDA-MB-231RR cells. Proliferation assays demonstrated their efficacy as cytotoxic agents against K-RasG13D mutant cancer cells and in inducing apoptosis. Clonogenic assays proven their ability to inhibit TNBC and radioresistant TNBC cell clonogenicity. In In vivo studies, C14 and P8 inhibited tumor growth and reduced proliferation, angiogenesis, and cell cycle progression markers.

Discussion

These findings suggest that C14 and P8 could serve as promising adjuvant treatments for TNBC, particularly for non-responders to standard therapies. By targeting overactivated K-Ras and its membrane transporter, these compounds offer potential therapeutic benefits against TNBC, including its radioresistant form. Further research and clinical trials are warranted to validate their efficacy and safety as novel TNBC treatments.

Technical consideration for breast reconstruction in patients requiring neoadjuvant or adjuvant radiotherapy: a narrative review

Background and Objective

Surgical considerations for breast reconstruction (BR) in patients requiring neoadjuvant radiotherapy (NART) or adjuvant radiotherapy (ART) cannot be understated. The management of irradiated tissue leads surgeons to face several challenges. Therefore, it is essential to comprehensively understand the proper patient selection and preoperative planning to ensure the best outcomes and minimize the risk of complications. This narrative review aims to provide an update and summary of the most important technical considerations every breast surgeon must contemplate reconstructing the irradiated breast.

Methods

The search strategy was performed on January 10th, 2023. The PubMed, Embase, Cochrane Library, and Web of Science databases were queried to capture all publications regarding surgical considerations in BR of patients undergoing NART and ART.

Key Content and Findings

This review shows that the effects of radiotherapy (RT) on BR are still being studied. RT represents an essential factor for overall patient survival, and its use is increasing. However, the range of RT treatments across different cancer centers complicates the creation of a single treatment protocol. BR improves women's quality of life, so finding the proper integration of BR and RT is essential. When deciding on the reconstructive method, there are several factors to consider, such as the patient's body characteristics, tumor stage, RT protocol, and chemotherapy. To achieve the best surgical results and the most satisfied patient, using less aggressive and safer RT methods in the treatment sequence is recommended.

Conclusions

The timing of the radiation will influence the selection of the best reconstructive methods to be employed in the breast cancer patient. However, there is clear evidence of preference for immediate autologous-based BR in cases due to the low rate of complications in the long term. But patient individualization is the key. Therefore, the benefits and risks of immediate versus delayed and autologous versus implant-based reconstruction must be weighed in every single case.

A narrative review for radiation oncologists to implement preoperative partial breast irradiation

The strategy to anticipate radiotherapy (RT) before surgery, for breast cancer (BC) treatment, has recently generated a renewed interest. Historically, preoperative RT has remained confined either to highly selected patients, in the context of personalized therapy, or to clinical research protocols. Nevertheless, in the recent years, thanks to technological advances and increased tumor biology understanding, RT has undergone great changes that have also impacted the preoperative settings, embracing the modern approach to breast cancer. In particular, the reappraisal of preoperative RT can be viewed within the broader view of personalized and tailored medicine. In fact, preoperative accelerated partial breast irradiation (APBI) allows a more precise target delineation, with less variability in contouring among radiation oncologists, and a smaller treatment volume, possibly leading to lower toxicity and to dose escalation programs. The aim of the present review, which represents a benchmark study for the AIRC IG-23118, is to report available data on different technical aspects of preoperative RT including dosimetric studies, patient's selection and set-up, constraints, target delineation and clinical results. These data, along with the ones that will become available from ongoing studies, may inform the design of the future trials and representing a step toward a tailored APBI approach with the potential to challenge the current treatment paradigm in early-stage BC.Trial registration: The study is registered at clinicaltrials.gov (NCT04679454).

Preoperative Radiotherapy Does Not Change the Existing Treatment Paradigm in Stage III Breast Cancer

INTRODUCTION

Radiotherapy (RT) plays an indispensable role in postoperative breast cancer treatment. This study aimed to assess the feasibility of preoperative RT for stage III breast cancer by comparing preoperative RT with postoperative RT in terms of overall survival (OS).

METHODS

Based on the information in the Surveillance, Epidemiology, and End Results database from 2000 to 2018, patients with stage III breast cancer who had undergone radical surgery and RT were divided into two groups: a preoperative RT group and a postoperative RT group. OS was calculated using Kaplan-Meier analysis. The Cox proportional hazards model was used to evaluate independent factors associated with OS. Propensity score matching (PSM) was used to balance stratification factors.

RESULTS

In total, 9,605 patients were enrolled, of whom 9,456 received postoperative RT and 149 received preoperative RT. After a median follow-up of 72 months, postoperative RT was found to be superior to preoperative RT in terms of OS (p < 0.000). Compared to the postoperative RT group, the preoperative RT group showed a significantly higher risk of overall mortality without PSM in univariate (OS: hazard ratio [HR] = 1.653, 95% confidence interval [CI]: 1.288-2.123, p < 0.000) and multivariate analyses (OS: HR = 1.409, 95% CI: 1.096-1.810, p = 0.007). After PSM, the OS of the postoperative RT group was superior to the OS in the preoperative RT group (p = 0.041). Compared with the postoperative RT group, the preoperative RT group showed a significantly higher risk of overall mortality without PSM in univariate (HR = 1.312, 95% CI: 1.010-1.704, p = 0.042) and multivariate analyses (HR = 1.466, 95% CI: 1.127-1.906, p = 0.004).

CONCLUSION

Preoperative RT does not improve OS in patients with stage III breast cancer and has a worse prognosis. Preoperative RT has not changed the existing treatment paradigm in the current therapeutic context for patients with stage III breast cancer.

Preoperative Partial Breast Irradiation in Patients with Low-Risk Breast Cancer: A Systematic Review of Literature

BACKGROUND

Preoperative instead of standard postoperative partial breast irradiation (PBI) after breast-conserving surgery (BCS) has the advantage of reducing the irradiated breast volume, toxicity, and number of radiotherapy sessions and can allow tumor downstaging. In this review, we assessed tumor response and clinical outcomes after preoperative PBI.

PATIENTS AND METHODS

We conducted a systematic review of studies on preoperative PBI in patients with low-risk breast cancer using the databases Ovid Medline, Embase.com, Web of Science (Core Collection), and Scopus (PROSPERO registration CRD42022301435). References of eligible manuscripts were checked for other relevant manuscripts. The primary outcome measure was pathologic complete response (pCR).

RESULTS

A total of eight prospective and one retrospective cohort study were identified (n = 359). In up to 42% of the patients, pCR was obtained and this increased after a longer interval between radiotherapy and BCS (0.5-8 months). After a maximum median follow-up of 5.0 years, three studies on external beam radiotherapy reported low local recurrence rates (0-3%) and overall survival of 97-100%. Acute toxicity consisted mainly of grade 1 skin toxicity (0-34%) and seroma (0-31%). Late toxicity was predominantly fibrosis grade 1 (46-100%) and grade 2 (10-11%). Cosmetic outcome was good to excellent in 78-100% of the patients.

CONCLUSIONS

Preoperative PBI showed a higher pCR rate after a longer interval between radiotherapy and BCS. Mild late toxicity and good oncological and cosmetic outcomes were reported. In the ongoing ABLATIVE-2 trial, BCS is performed at a longer interval of 12 months after preoperative PBI aiming to achieve a higher pCR rate.

Use of tumour bed boost radiotherapy in volume replacement oncoplastic breast surgery: A systematic review

Tumour bed boost radiotherapy (RT) following breast conserving surgery reduces local recurrence in high-risk disease. There is recent debate over challenges to accurately localise tumour bed for RT boost delivery following volume replacement oncoplastic breast surgery (VR-OBS). This review evaluates the reporting of RT boost following VR-OBS in the literature published between January 2010 and December 2021. This review was in line with Preferred Reporting Items for Systematic Reviews and Metaanalysis statement.Nine studies met the inclusion criteria (n=670 patients), and RT boost was used in eight studies. Boost was administered in total to 384 patients (62.5% of irradiated patients). Only two studies reported boost planned target volumes and only one compared these against surgical specimen volumes.RT boost was not reported in most published studies on VR-OBS. Future prospective research are strongly needed to evaluate long-term outcomes of VR-OBS following RT boost, especially on breast cosmesis and patients' satisfaction. DATA AVAILABILITY: Data will be made available upon request.

Neoadjuvant radiohormonal therapy for oligo-metastatic prostate cancer: safety and efficacy outcomes from an open-label, dose-escalation, single-center, phase I/II clinical trial

To evaluate the safety and efficacy of neoadjuvant radiohormonal therapy for oligometastatic prostate cancer (OMPC), we conducted a 3 + 3 dose escalation, prospective, phase I/II, single-arm clinical trial (CHiCTR1900025743), in which long-term neoadjuvant androgen deprivation was adopted 1 month before radiotherapy, comprising intensity modulated radiotherapy to the pelvis, and stereotactic body radiation therapy to all extra-pelvic bone metastases for 4-7 weeks, at 39.6, 45, 50.4, and 54 Gy. Robotic-assisted radical prostatectomy was performed after 5-14 weeks. The primary outcome was treatment-related toxicities and adverse events; secondary outcomes were radiological treatment response, positive surgical margin (pSM), postoperative prostate-specific antigen (PSA), pathological down-grading and tumor regression grade, and survival parameters. Twelve patients were recruited from March 2019 to February 2020, aging 66.2 years in average (range, 52-80). Median baseline PSA was 62.0 ng/mL. All underwent RARP successfully without open conversions. Ten patients recorded pathological tumor down-staging (83.3%), and 5 (41.7%) with cN1 recorded negative regional lymph nodes on final pathology. 66.7% (8/12) recorded tumor regression grading (TRG) -I and 25% (3/12) recorded TRG-II. Median follow-up was 16.5 months. Mean radiological progression-free survival (RPFS) was 21.3 months, with 2-year RPFS of 83.3%. In all, neoadjuvant radiohormonal therapy is well tolerated for oligometastatic prostate cancer.

Preoperative Radio(Chemo)Therapy in Breast Cancer: Time to Switch the Perspective?

AIM

Radiation therapy represents, together with surgery and systemic treatment, the triad on which the current management of patients with breast cancer is based, achieving high control and survival rates. In recent years we have witnessed a (r)evolution in the conception of breast cancer treatment. The classic scheme of surgery followed by systemic treatment and radiotherapy is being subverted and it is becoming more and more frequent to propose the primary administration of systemic treatment before surgery, seeking to maximize its effect and favoring not only the performance of more conservative surgeries but also, in selected cases, increasing the rates of disease-free survival and overall survival. Radiotherapy is also evolving toward a change in perspective: considering preoperative primary administration of radiotherapy may be useful in selected groups. Advances in radiobiological knowledge, together with technological improvements that are constantly being incorporated into clinical practice, support the administration of increasingly reliable, precise, and effective radiotherapy, as well as its safe combination with antitumor drugs or immunotherapy in the primary preoperative context. In this paper, we present a narrative review of the usefulness of preoperative radiotherapy for breast cancer patients and the possibilities for its combination with other therapies.

Surgery-mediated tumor-promoting effects on the immune microenvironment

Surgical resection continues to be the mainstay treatment for solid cancers even though chemotherapy and immunotherapy have significantly improved patient overall survival and progression-free survival. Numerous studies have shown that surgery induces the dissemination of circulating tumor cells (CTCs) and that the resultant inflammatory response promotes occult tumor growth and the metastatic process by forming a supportive tumor microenvironment (TME). Surgery-induced platelet activation is one of the initial responses to a wound and the formation of fibrin clots can provide the scaffold for recruited inflammatory cells. Activated platelets can also shield CTCs to protect them from blood shear forces and promote CTCs evasion of immune destruction. Similarly, neutrophils are recruited to the fibrin clot and enhance cancer metastatic dissemination and progression by forming neutrophil extracellular traps (NETs). Activated macrophages are also recruited to surgical sites to facilitate the metastatic spread. More importantly, the body's response to surgical insult results in the recruitment and expansion of immunosuppressive cell populations (i.e. myeloid-derived suppressor cells and regulatory T cells) and in the suppression of natural killer (NK) cells that contribute to postoperative cancer recurrence and metastasis. In this review, we seek to provide an overview of the pro-tumorigenic mechanisms resulting from surgery's impact on these cells in the TME. Further understanding of these events will allow for the development of perioperative therapeutic strategies to prevent surgery-associated metastasis.

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.

Primary Chemoradiotherapy Treatment (PCRT) for HER2+ and Triple Negative Breast Cancer Patients: A Feasible Combination

Primary systemic treatment (PST) downsizes the tumor and improves pathological response. The aim of this study is to analyze the feasibility and tolerance of primary concurrent radio−chemotherapy (PCRT) in breast cancer patients. Patients with localized TN/HER2+ tumors were enrolled in this prospective study. Radiation was delivered concomitantly during the first 3 weeks of chemotherapy, and it was based on a 15 fractions scheme, 40.5 Gy/2.7 Gy per fraction to whole breast and nodal levels I-IV. Chemotherapy (CT) was based on Pertuzumab−Trastuzumab−Paclitaxel followed by anthracyclines in HER2+ and CBDCA-Paclitaxel followed by anthracyclines in TN breast cancers patients. A total of 58 patients were enrolled; 25 patients (43%) were TN and 33 patients HER2+ (57%). With a median follow-up of 24.2 months, 56 patients completed PCRT and surgery. A total of 35 patients (87.5%) achieved >90% loss of invasive carcinoma cells in the surgical specimen. The 70.8% and the 53.1% of patients with TN and HER-2+ subtype, respectively, achieved complete pathological response (pCR). This is the first study of concurrent neoadjuvant treatment in breast cancer in which three strategies were applied simultaneously: fractionation of RT (radiotherapy) in 15 sessions, adjustment of CT to tumor phenotype and local planning by PET. The pCR rates are encouraging.

Survival comparison between postoperative and preoperative radiotherapy for stage I-III non-inflammatory breast cancer

To compare the survival benefit between preoperative and postoperative radiotherapy for stage I-III non-inflammatory breast cancer patients, we conducted a retrospective cohort study using surveillance, epidemiology and end results databases. Our study recruited patients who had been diagnosed with stage I-III breast cancer and underwent surgery and radiotherapy. The overall survival was calculated by Kaplan-Meier method. Cox risk model was used to determine the impact of radiotherapy according to stage, molecular subtype and other risk factors. Propensity score matching was used to balance measurable confounding factors. Of all the 411,279 enrolled patients varying from 1975 to 2016, 1712 patients received preoperative radiotherapy, and 409,567 patients received postoperative radiotherapy. Compared with the postoperative radiotherapy group, the preoperative radiotherapy group showed significantly higher risks of overall mortality and breast cancer-specific mortality. Survival differences in treatment sequences were correlated with stage, molecular subtypes and other risk factors. According to the results of this study, preoperative radiotherapy did not show a survival advantage, and postoperative radiotherapy is still the primary treatment. However, preoperative radiotherapy also has some theoretical advantages, such as phase reduction and recurrence reduction. Therefore, it is still worthy of further exploration.

Predictive Factors of Long-Term Survival after Neoadjuvant Radiotherapy and Chemotherapy in High-Risk Breast Cancer

BACKGROUND

Neoadjuvant radiotherapy (naRT) in addition to neoadjuvant chemotherapy (naCT) has been used for locally advanced, inoperable breast cancer or to allow breast conserving surgery (BCS). Retrospective analyses suggest that naRT + naCT might result in an improvement in pathological complete response (pCR rate and disease-free survival). pCR is a surrogate parameter for improved event-free and overall survival (OS) and allows for the adaption of the post-neoadjuvant therapy regimens. However, it is not clear whether pCR achieved with the addition of naRT has the same prognostic value.

PATIENTS AND METHODS

We performed a retrospective re-analysis of 356 patients (cT1-cT4/cN0-N+) treated with naRT and naCT with a long-term follow-up. Patients underwent naRT on the breast and regional lymph nodes combined with a boost to the primary tumor. Chemotherapy with different agents was given either sequentially or concomitantly to naRT. We used the Cox proportional hazard regression model to estimate the effect of pCR in our cohort in different subgroups as well as chemotherapy protocols. Clinical response markers correlating with OS were also analyzed.

RESULTS

For patients with median follow-ups of 20 years, 10 years, 15 years, 20 years, and 25 years, OS rates were 69.7%, 60.6%, 53.1%, and 45.1%, respectively. pCR was achieved in 31.1% of patients and associated with a significant improvement in OS (HR = 0.58; CI-95%: 0.41-0.80; p = 0.001). The prognostic impact of pCR was evident across breast cancer subtypes and chemotherapy regimens. Multivariate analysis showed that age, clinical tumor and nodal stage, chemotherapy, and pCR were prognostic for OS.

CONCLUSION

NaCT and naRT prior to surgical resection achieve good long-term survival in high-risk breast cancer. pCR after naRT maintains its prognostic value in breast cancer subtypes and across different subgroups. pCR driven by naRT and naCT independently influences long-term survival.

Aggregation-induced emission photosensitizer-based photodynamic therapy in cancer: from chemical to clinical

Cancer remains a serious threat to human health owing to the lack of effective treatments. Photodynamic therapy (PDT) has emerged as a promising non-invasive cancer treatment that consists of three main elements: photosensitizers (PSs), light and oxygen. However, some traditional PSs are prone to aggregation-caused quenching (ACQ), leading to reduced reactive oxygen species (ROS) generation capacity. Aggregation-induced emission (AIE)-PSs, due to their distorted structure, suppress the strong molecular interactions, making them more photosensitive in the aggregated state instead. Activated by light, they can efficiently produce ROS and induce cell death. PS is one of the core factors of efficient PDT, so proceeding from the design and preparation of AIE-PSs, including how to manipulate the electron donor (D) and receptor (A) in the PSs configuration, introduce heavy atoms or metal complexes, design of Type I AIE-PSs, polymerization-enhanced photosensitization and nano-engineering approaches. Then, the preclinical experiments of AIE-PSs in treating different types of tumors, such as ovarian cancer, cervical cancer, lung cancer, breast cancer, and its great potential clinical applications are discussed. In addition, some perspectives on the further development of AIE-PSs are presented. This review hopes to stimulate the interest of researchers in different fields such as chemistry, materials science, biology, and medicine, and promote the clinical translation of AIE-PSs.

Mathematical modeling of radiotherapy and its impact on tumor interactions with the immune system

Radiotherapy is a primary therapeutic modality widely utilized with curative intent. Traditionally tumor response was hypothesized to be due to high levels of cell death induced by irreparable DNA damage. However, the immunomodulatory aspect of radiation is now widely accepted. As such, interest into the combination of radiotherapy and immunotherapy is increasing, the synergy of which has the potential to improve tumor regression beyond that observed after either treatment alone. However, questions regarding the timing (sequential vs concurrent) and dose fractionation (hyper-, standard-, or hypo-fractionation) that result in improved anti-tumor immune responses, and thus potentially enhanced tumor inhibition, remain. Here we discuss the biological response to radiotherapy and its immunomodulatory properties before giving an overview of pre-clinical data and clinical trials concerned with answering these questions. Finally, we review published mathematical models of the impact of radiotherapy on tumor-immune interactions. Ranging from considering the impact of properties of the tumor microenvironment on the induction of anti-tumor responses, to the impact of choice of radiation site in the setting of metastatic disease, these models all have an underlying feature in common: the push towards personalized therapy.

Safety and efficacy of immediate autologous breast reconstruction after mastectomy in patients undergoing neoadjuvant chemoradiotherapy for locally advanced breast cancer

PURPOSE

Immediate autologous breast reconstruction (IABR) offers fewer surgeries with better psychosocial, quality of life and aesthetic outcomes. In high-risk patients or those with locally advanced breast cancer (LABC), adjuvant postmastectomy radiotherapy decreases local recurrence and improves survival. However, it has negative effects on the reconstructed flap. Reversing the treatment protocol using neoadjuvant radiotherapy may minimise the negative effects on the reconstructed breast in women requesting IABR. We assessed the safety and efficacy of women who underwent mastectomy and IABR post-neoadjuvant chemoradiotherapy (NACRT) for LABC.

METHODOLOGY

A cohort study using a retrospective and prospective analysis was performed on women with LABC who underwent mastectomy and IABR post-NACRT between 1998 and 2018. All reconstructions were performed by oncoplastic breast surgeons from a single unit. Outcome measures analysed included surgical complications, flap failure, loco-regional recurrence, overall and disease-free survival. This study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). This study was approved by the institutional review board.

RESULTS

A total of 28 women with a median age of 50 (33-64) were included. 25% underwent TRAM flap and 75% underwent LD flap reconstruction. The median period of follow-up was 61 months. Post-NACRT, 35.7% achieved complete pathological response (PCR). 3/28 (10.7%) had early complications (2 implant and 1 donor site infection). 7% underwent revision surgery. There was no flap loss. 1/28 (3.5%) had loco-regional recurrence, 3.2% had distant metastasis, and 2.5% had breast cancer related mortality.

CONCLUSION

In women with LABC, NACRT followed by mastectomy and IABR is safe and may not compromise oncological and cosmetic outcomes. If offers the benefits of immediate breast reconstruction and avoids delaying adjuvant therapy.

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

Background

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

Methods

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

Discussion

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

Trial registration

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

Safety of pre- or postoperative accelerated radiotherapy in 5 fractions: A randomized pilot trial

OBJECTIVE

Neo-adjuvant radiotherapy (NART) for breast cancer has shown promising survival results in retrospective trials. However, there are some obstacles such as a chemotherapy delay, an increased overall treatment time (OTT) and the risk of increasing surgical morbidity. Accelerated radiotherapy (RT) in 5 fractions allows to deliver NART in a very short time span and minimizes the delay of surgery and chemotherapy. This trial investigates this NART schedule for safety, feasibility and OTT.

MATERIAL AND METHODS

Twenty patients eligible for neo-adjuvant chemotherapy (NACT) and breast conserving surgery, were randomized between NART before NACT or NACT and postoperative RT. In both arms, RT treatment was given in 5 fractions to the whole breast with a simultaneously integrated boost (SIB) on the tumor(bed). Lymph node irradiation was given concomitantly in case of lymph node involvement. OTT was defined as the time from diagnosis to last surgery in the intervention group, while in the control group the time between diagnosis and last RT-fraction was used. In the intervention group NACT-delay was defined as time between diagnosis and start of chemotherapy.

RESULTS

20 patients were included, and 19 patients completed treatment. OTT was significantly shorter in the intervention group (mean 218 days, range 196-253) compared to the control group (mean 237, range 211-268, p = 0.001). The difference in mean duration from diagnosis to the first treatment was a non-significant 4 days longer (31 vs 27 days, p = 0.28), but the start of NACT after diagnosis was delayed by 21 days (48 vs 27 days, p < 0.001). NART did not result in additional surgery complications.

CONCLUSION

This pilot trial is the first to report on accelerated NART in 5 fractions with SIB. NART before NACT resulted in a shorter OTT with good safety results.

Integration of immune and hypoxia gene signatures improves the prediction of radiosensitivity in breast cancer

Immunity and hypoxia are two important factors that affect the response of cancer patients to radiotherapy. At the same time, considering the limited predictive value of a single predictive model and the uncertainty of grouping patients near the cutoff value, we developed and validated a combined model based on immune- and hypoxia-related gene expression profiles to predict the radiosensitivity of breast cancer patients. This study was based on breast cancer data from The Cancer Genome Atlas (TCGA). Spike-and-slab Lasso regression analysis was performed to select three immune-related genes and develop a radiosensitivity model. Lasso Cox regression modeling selected 11 hypoxia-related genes for development of radiosensitivity model. Three independent datasets (Molecular Taxonomy of Breast Cancer International Consortium [METABRIC], E-TABM-158, GSE103746) were used to validate the predictive value of radiosensitivity signatures. In the TCGA dataset, the 10-year survival probabilities of the immune radioresistant (IRR) and hypoxia radioresistant (HRR) groups were 0.189 (0.037, 0.973) and 0.477 (0.293, 0.776), respectively. The 10-year survival probabilities of the immune radiosensitive (IRS) and hypoxia radiosensitive (HRS) groups were 0.778 (0.676, 0.895) and 0.824 (0.723, 0.939), respectively. Based on these two gene signatures, we further constructed a combined model and divided all patients into three groups (IRS/HRS, mixed, IRR/HRR). We identified the IRS/HRS patients most likely to benefit from radiotherapy; the 10-year survival probability was 0.886 (0.806, 0.976). The 10-year survival probability of the IRR/HRR group was 0. In conclusion, a combined model integrating immune- and hypoxia-related gene signatures could effectively predict the radiosensitivity of breast cancer and more accurately identify radiosensitive and radioresistant patients than a single model.

Psychological Distress, Coping Strategies, and Quality of Life in Breast Cancer Patients Under Neoadjuvant Therapy: Protocol of a Systematic Review

Introduction

Women with breast cancer eligible for neoadjuvant therapy (NAT) present a disorder of biopsychosocial variables and alteration of their quality of life. They cope with this changing by adopting psychological adjustment strategies, either passive or active. This systematic review aims to investigate the psychological distress, coping strategies, and quality of life in breast cancer patients under neoadjuvant therapy.

Methods

Cochrane Library, PubMed, ScienceDirect, Scopus, Web of Science, and Wiley Online library represent the databases that were searched to identify relevant published articles until September 27, 2021. Full-text published articles, written in English and assessing the main outcomes (namely: psychological distress, coping strategies, and quality of life) in women with breast cancer under NAT will be included. Also, we will integrate papers dealing with the related bio psychosocial variables to the main variables. The paper selection, data extraction, and quality assessment of selected studies will be performed independently by two researchers, and disagreements will be resolved through discussions. We will bring together the results of all of the included studies to draw conclusions based on the body of evidence. The narrative approach will be adopted to analyze the results and conclusions extracted and we would perform quantitative groupings if we have similar data.

Ethics and dissemination

Ethical approval is not required as the proposed systematic review will not use primary data. The results of this review will be disseminated through publication in a peer-reviewed journal and conference presentation(s). PROSPERO registration number: CRD42021230300.

Potassium Iodide Nanoparticles Enhance Radiotherapy against Breast Cancer by Exploiting the Sodium-Iodide Symporter

Iodine has shown promise in enhancing radiotherapy. However, conventional iodine compounds show fast clearance and low retention inside cancer cells, limiting their application as a radiosensitizer. Herein, we synthesize poly(maleic anhydride-alt-1-octadecene) coated KI nanoparticles (PMAO-KI NPs) and evaluate their potential for enhancing radiotherapy. Owing to the polymer coating, the KI core of PMAO-KI NPs is not instantly dissolved in aqueous solutions but slowly degraded, allowing for controlled release of iodide (I-). I- is transported into cells via the sodium iodide symporter (NIS), which is upregulated in breast cancer cells. Our results show that PMAO-KI NPs can enhance radiation-induced production of reactive oxygen species such as hydroxyl radicals. When tested in vitro with MCF-7 cells, PMAO-KI NPs promote radiation-induced DNA double-strand breaks and lipid peroxidation, causing a drop in cancer cell viability and reproductivity. When tested in MCF-7 bearing mice, PMAO-KI NPs show significant radiosensitizing effects, leading to complete tumor eradication in 80% of the treated animals without inducing additional toxicity. Overall, our strategy exploits electrolyte nanoparticles to deliver iodide into cancer cells through NIS, thus promoting radiotherapy against breast cancer.

Developing ZNF Gene Signatures Predicting Radiosensitivity of Patients with Breast Cancer

Adjuvant radiotherapy is one of the main treatment methods for breast cancer, but its clinical benefit depends largely on the characteristics of the patient. This study aimed to explore the relationship between the expression of zinc finger (ZNF) gene family proteins and the radiosensitivity of breast cancer patients. Clinical and gene expression data on a total of 976 breast cancer samples were obtained from The Cancer Genome Atlas (TCGA) database. ZNF gene expression was dichotomized into groups with a higher or lower level than the median level of expression. Univariate and multivariate Cox regression analyses were used to evaluate the relationship between ZNF gene expression levels and radiosensitivity. The Molecular Taxonomy Data of the International Federation of Breast Cancer (METABRIC) database was used for validation. The results revealed that 4 ZNF genes were possible radiosensitivity markers. High expression of ZNF644 and low expression levels of the other 3 genes (ZNF341, ZNF541, and ZNF653) were related to the radiosensitivity of breast cancer. Hierarchical cluster, Cox, and CoxBoost analysis based on these 4 ZNF genes indicated that patients with a favorable 4-gene signature had better overall survival on radiotherapy. Thus, this 4-gene signature may have value for selecting those patients most likely to benefit from radiotherapy. ZNF gene clusters could act as radiosensitivity signatures for breast cancer patients and may be involved in determining the radiosensitivity of cancer.

A Novel Approach for the Discovery of Biomarkers of Radiotherapy Response in Breast Cancer

Radiotherapy (RT) is an important treatment modality for the local control of breast cancer (BC). Unfortunately, not all patients that receive RT will obtain a therapeutic benefit, as cancer cells that either possess intrinsic radioresistance or develop resistance during treatment can reduce its efficacy. For RT treatment regimens to become personalised, there is a need to identify biomarkers that can predict and/or monitor a tumour's response to radiation. Here we describe a novel method to identify such biomarkers. Liquid chromatography-mass spectrometry (LC-MS) was used on conditioned media (CM) samples from a radiosensitive oestrogen receptor positive (ER⁺) BC cell line (MCF-7) to identify cancer-secreted biomarkers which reflected a response to radiation. A total of 33 radiation-induced secreted proteins that had higher (up to 12-fold) secretion levels at 24 h post-2 Gy radiation were identified. Secretomic results were combined with whole-transcriptome gene expression experiments, using both radiosensitive and radioresistant cells, to identify a signature related to intrinsic radiosensitivity. Gene expression analysis assessing the levels of the 33 proteins showed that 5 (YBX3, EIF4EBP2, DKK1, GNPNAT1 and TK1) had higher expression levels in the radiosensitive cells compared to their radioresistant derivatives; 3 of these proteins (DKK1, GNPNAT1 and TK1) underwent in-lab and initial clinical validation. Western blot analysis using CM samples from cell lines confirmed a significant increase in the release of each candidate biomarker from radiosensitive cells 24 h after treatment with a 2 Gy dose of radiation; no significant increase in secretion was observed in the radioresistant cells after radiation. Immunohistochemistry showed that higher intracellular protein levels of the biomarkers were associated with greater radiosensitivity. Intracellular levels were further assessed in pre-treatment biopsy tissues from patients diagnosed with ER⁺ BC that were subsequently treated with breast-conserving surgery and RT. High DKK1 and GNPNAT1 intracellular levels were associated with significantly increased recurrence-free survival times, indicating that these two candidate biomarkers have the potential to predict sensitivity to RT. We suggest that the methods highlighted in this study could be utilised for the identification of biomarkers that may have a potential clinical role in personalising and optimising RT dosing regimens, whilst limiting the administration of RT to patients who are unlikely to benefit.

MRI Response to Pre-operative Stereotactic Ablative Body Radiotherapy (SABR) in Early Stage ER/PR+ HER2- Breast Cancer correlates with Surgical Pathology Tumor Bed Cellularity

OBJECTIVE

This study evaluates breast MRI response of ER/PR+ HER2- breast tumors to pre-operative SABR with pathologic response correlation.

METHODS

Women enrolled in a phase 2 single institution trial of SABR for ER/PR+ HER2- breast cancer were retrospectively evaluated for radiologic-pathologic correlation of tumor response. These patients underwent baseline breast MRI, SABR (28.5 Gy in 3 fractions), follow-up MRI 5 to 6 weeks post-SABR, and lumpectomy. Tumor size and BI-RADS descriptors on pre and post-SABR breast MRIs were compared to determine correlation with surgical specimen % tumor cellularity (%TC). Reported MRI tumor dimensions were used to calculate percent cubic volume remaining (%VR). Partial MRI response was defined as a BI-RADs descriptor change or %VR ≤ 70%, while partial pathologic response (pPR) was defined as %TC ≤ 70%.

RESULTS

Nineteen patients completed the trial, and %TC ranged 10% to 80%. For BI-RADS descriptor analysis, 12 of 19 (63%) showed change in lesion or kinetic enhancement descriptors post-SABR. This was associated with lower %TC (29% vs. 47%, P = .042). BI-RADS descriptor change analysis also demonstrated high PPV (100%) and specificity (100%) for predicting pPR to treatment (sensitivity 71%, accuracy 74%), but low NPV (29%). MRI %VR demonstrated strong linear correlation with %TC (R = 0.70, P < .001, Pearson's Correlation) and high accuracy (89%) for predicting pPR (sensitivity 88%, specificity 100%, PPV 100%, and NPV 50%).

CONCLUSION

Evaluating breast cancer response on MRI using %VR after pre-operative SABR treatment can help identify patients benefiting the most from neoadjuvant radiation treatment of their ER/PR+ HER2- tumors, a group in which pCR to neoadjuvant therapy is rare.

Neoadjuvant radiotherapy for locally advanced and high-risk breast cancer

INTRODUCTION

Neoadjuvant radiotherapy (NART) as part of a multi-modality approach for locally advanced breast cancer (LABC) requires further investigation. Importantly, this approach may allow for a single-staged surgical procedure, with mastectomy and immediate autologous reconstruction. Multiple other potential benefits of NART include improved pathological downstaging of breast disease, reduced overall treatment time, elimination of time period with breast tissue deficit and improved patient satisfaction.

METHODS

This is a retrospective multi-institutional review of patients with LABC and high-risk breast disease undergoing NART. Eligible patients sequentially underwent neoadjuvant chemotherapy (NACT) with or without HER2-targeted therapy, NART, followed by mastectomy with immediate autologous breast reconstruction (BR) 4- to 6 weeks post-completion of radiotherapy. Patient and tumour characteristics were analysed using descriptive statistics. Surgical complications were assessed using the Clavien-Dindo Classification (Ann Surg 2004; 240: 205).

RESULTS

From 3/2013 to 9/2019, 153 patients were treated with NART. The median age was 47 years (IQR 42-52), with median body mass index of 27. Eighteen patients experienced Grade 3 acute surgical complications. This included 13 Grade 3B breast-site events and 9 Grade 3B donor-site events, where further surgical intervention was required for management of wound infection, wound dehiscence, flap or mastectomy skin necrosis, haematoma and internal mammary venous anastomotic thrombosis. No autologous flap loss was observed.

CONCLUSION

Neoadjuvant radiotherapy facilitates a single-stage surgical procedure with mastectomy and immediate autologous BR, eliminating the delay to reconstructive surgery and thus shortening a woman's breast cancer journey. The findings of this review support the use of NART, with comparable rates of surgical complications to standard sequencing.

A systematic review of neo-adjuvant radiotherapy in the treatment of breast cancer

Introduction

The use of neo-adjuvant radiotherapy (NRT) has been proven effective at improving cancer related outcome measures, including overall-survival (OS) in the management of solid cancers. However, its utilisation in breast cancer has not been explored to the extent of neo-adjuvant chemotherapy (NAC). The evidence for the application of NRT in breast cancer is evaluated.

Methods

PubMed, Embase and the Cochrane Library databases were searched systematically in August 2020 for studies that addressed the role of NRT in the treatment of breast cancer. Studies were deemed eligible if they reported on objective outcome measurements of OS, disease free-survival (DFS) or pathological complete response (pCR) and attained a satisfactory quality assessment.

Findings

A total of 23 studies reported upon 3,766 patients who had received NRT of which 3,233 also received NAC concurrently (neo-adjuvant chemo-radiotherapy (NCRT)). The pCR values ranged from 14% to 42%, 5-year DFS 61.4% to 81% and 5-year OS 71.6% to 84.2%. Complications were confined to radiation dermatitis with no cases of implant loss reported during breast reconstruction. The application of NRCT alone showed no significant difference in OS or DFS compared to NCRT followed by surgery.

Interpretation

Numbers of patients receiving exclusively NRT is small. However, NCRT is oncologically safe with a low side-effect profile including preceding breast reconstruction. Potential benefits include precise cancer volume targeting, chemosensitisation, elimination of delays in adjuvant therapies and alternatives to chemotherapy in oestrogen receptor positive patients. These factors warrant further exploration within randomised controlled-trials.

Role of miRNAs in regulating responses to radiotherapy in human breast cancer

Breast cancer is the most common type of cancer that affects females globally. Radiotherapy is a standard treatment option for breast cancer, where one of its most significant limitations is radioresistance development. MicroRNAs (miRNAs) are small, non-protein-coding RNAs that have been widely studied for their roles as disease biomarkers. To date, several in vitro, in vivo, and clinical studies have reported the roles of miRNAs in regulating radiosensitivity and radioresistance in breast cancer cells. This article reviews the roles of miRNAs in regulating treatment response toward radiotherapy and the associating cellular pathways. We identified 36 miRNAs that play a role in mediating radio-responses; 22 were radiosensitizing, 12 were radioresistance-promoting, and two miRNAs were reported to promote both effects. A brief overview of breast cancer therapy options, mechanism of action of radiation, and molecular mechanism of radioresistance was provided in this article. A summary of the latest clinical researches involving miRNAs in breast cancer radiotherapy was also included.

Hypoxia and perfusion in breast cancer: simultaneous assessment using PET/MR imaging

OBJECTIVES

Hypoxia is associated with poor prognosis and treatment resistance in breast cancer. However, the temporally variant nature of hypoxia can complicate interpretation of imaging findings. We explored the relationship between hypoxia and vascular function in breast tumours through combined 18F-fluoromisonidazole (18 F-FMISO) PET/MRI, with simultaneous assessment circumventing the effect of temporal variation in hypoxia and perfusion.

METHODS

Women with histologically confirmed, primary breast cancer underwent a simultaneous 18F-FMISO-PET/MR examination. Tumour hypoxia was assessed using influx rate constant Ki and hypoxic fractions (%HF), while parameters of vascular function (Ktrans, kep, ve, vp) and cellularity (ADC) were derived from dynamic contrast-enhanced (DCE) and diffusion-weighted (DW)-MRI, respectively. Additional correlates included histological subtype, grade and size. Relationships between imaging variables were assessed using Pearson correlation (r).

RESULTS

Twenty-nine women with 32 lesions were assessed. Hypoxic fractions > 1% were observed in 6/32 (19%) cancers, while 18/32 (56%) tumours showed a %HF of zero. The presence of hypoxia in lesions was independent of histological subtype or grade. Mean tumour Ktrans correlated negatively with Ki (r = - 0.38, p = 0.04) and %HF (r = - 0.33, p = 0.04), though parametric maps exhibited intratumoural heterogeneity with hypoxic regions colocalising with both hypo- and hyperperfused areas. No correlation was observed between ADC and DCE-MRI or PET parameters. %HF correlated positively with lesion size (r = 0.63, p = 0.001).

CONCLUSION

Hypoxia measured by 18F-FMISO-PET correlated negatively with Ktrans from DCE-MRI, supporting the hypothesis of perfusion-driven hypoxia in breast cancer. Intratumoural hypoxia-perfusion relationships were heterogeneous, suggesting that combined assessment may be needed for disease characterisation, which could be achieved using simultaneous multimodality imaging.

KEY POINTS

• At the tumour level, hypoxia measured by 18F-FMISO-PET was negatively correlated with perfusion measured by DCE-MRI, which supports the hypothesis of perfusion-driven hypoxia in breast cancer. • No associations were observed between 18F-FMISO-PET parameters and tumour histology or grade, but tumour hypoxic fractions increased with lesion size. • Intratumoural hypoxia-perfusion relationships were heterogeneous, suggesting that the combined hypoxia-perfusion status of tumours may need to be considered for disease characterisation, which can be achieved via simultaneous multimodality imaging as reported here.

Dichloroacetate Radiosensitizes Hypoxic Breast Cancer Cells

Mitochondrial metabolism is an attractive target for cancer therapy. Reprogramming metabolic pathways can potentially sensitize tumors with limited treatment options, such as triple-negative breast cancer (TNBC), to chemo- and/or radiotherapy. Dichloroacetate (DCA) is a specific inhibitor of the pyruvate dehydrogenase kinase (PDK), which leads to enhanced reactive oxygen species (ROS) production. ROS are the primary effector molecules of radiation and an increase hereof will enhance the radioresponse. In this study, we evaluated the effects of DCA and radiotherapy on two TNBC cell lines, namely EMT6 and 4T1, under aerobic and hypoxic conditions. As expected, DCA treatment decreased phosphorylated pyruvate dehydrogenase (PDH) and lowered both extracellular acidification rate (ECAR) and lactate production. Remarkably, DCA treatment led to a significant increase in ROS production (up to 15-fold) in hypoxic cancer cells but not in aerobic cells. Consistently, DCA radiosensitized hypoxic tumor cells and 3D spheroids while leaving the intrinsic radiosensitivity of the tumor cells unchanged. Our results suggest that although described as an oxidative phosphorylation (OXPHOS)-promoting drug, DCA can also increase hypoxic radioresponses. This study therefore paves the way for the targeting of mitochondrial metabolism of hypoxic cancer cells, in particular to combat radioresistance.

Feasibility study on pre or postoperative accelerated radiotherapy (POP-ART) in breast cancer patients

Background

In early-stage breast cancer, the cornerstone of treatment is surgery. After breast-conserving surgery, adjuvant radiotherapy has shown to improve locoregional control and overall survival rates. The use of breast radiotherapy in the preoperative (preop) setting is far less common. Nevertheless, it might improve disease-free survival as compared to postoperative radiotherapy. There is also a possibility of downsizing the tumour which might lead to a lower need for mastectomy. There are some obstacles that complicate its introduction into daily practice. It may complicate surgery or lead to an increase in wound complications or delayed wound healing. Another fear of preop radiotherapy is delaying surgery for too long. At Ghent University Hospital, we have experience with a 5-fraction radiotherapy schedule allowing radiotherapy delivery in a very short time span.

Methods

Twenty female breast cancer patients with non-metastatic disease receiving preop chemotherapy will be randomized between preop or postoperative radiotherapy. The feasibility of preop radiotherapy will be evaluated based on overall treatment time. All patients will be treated in 5 fractions of 5.7 Gy to the whole breast with a simultaneous integrated boost to the tumour/tumour bed of 5 × 6.2 Gy. In case of lymph node irradiation, the lymph node regions will receive a dose of 27 Gy in 5 fractions of 5.4 Gy. The total duration of therapy will be 10 to 12 days. In the preop group, overall treatment time is defined as the time between diagnosis and the day of last surgery, in the postop group between diagnosis and last irradiation fraction. Toxicity related to surgery, radio-, and chemotherapy will be evaluated on dedicated case-report forms at predefined time points. Tumour response will be evaluated on the pathology report and on MRI at baseline and in the interval between chemotherapy and surgery.

Discussion

The primary objective of the trial is to investigate the feasibility of preop radiotherapy. Secondary objectives are to search for biomarkers of response and toxicity and identify the involved cell death mechanisms and the effect of preop breast radiotherapy on the in-situ immune micro-environment.

The 8-Year Management of an Older Breast Cancer Patient by Non-surgical Primary Therapies and Minimized Surgery: A Case Report

A 74-year-old woman presented with a palpable lesion in her right breast. At the time of her visit, she was taking medications for diabetes, hypertension, tremors, tinnitus, and lumbago. She was also caring for her husband, who had dementia. Imaging studies revealed another lesion in addition to the palpable mass. A core biopsy of the palpable mass confirmed invasive ductal carcinoma. Surgery was recommended to remove both masses. However, the patient refused the operation due to her comorbidities and her husband's nursing needs. A modified treatment process, including non-surgical primary therapies, minimized surgery, and close follow-up, for 8 years proved successful. This report focuses on the points to consider in the treatment and management of older patients with breast cancer.

High School Internship Program in Integrated Mathematical Oncology (HIP IMO): Five-Year Experience at Moffitt Cancer Center

Modern cancer research, and the wealth of data across multiple spatial and temporal scales, has created the need for researchers that are well versed in the life sciences (cancer biology, developmental biology, immunology), medical sciences (oncology) and natural sciences (mathematics, physics, engineering, computer sciences). College undergraduate education traditionally occurs in disciplinary silos, which creates a steep learning curve at the graduate and postdoctoral levels that increasingly bridge multiple disciplines. Numerous colleges have begun to embrace interdisciplinary curricula, but students who double major in mathematics (or other quantitative sciences) and biology (or medicine) remain scarce. We identified the need to educate junior and senior high school students about integrating mathematical and biological skills, through the lens of mathematical oncology, to better prepare students for future careers at the interdisciplinary interface. The High school Internship Program in Integrated Mathematical Oncology (HIP IMO) at Moffitt Cancer Center has so far trained 59 students between 2015 and 2019. We report here on the program structure, training deliverables, curriculum and outcomes. We hope to promote interdisciplinary educational activities early in a student's career.

Immunologic Consequences of Sequencing Cancer Radiotherapy and Surgery

PURPOSE

Early-stage cancers are routinely treated with surgery followed by radiotherapy (SR). Radiotherapy before surgery (RS) has been widely ignored for some cancers. We evaluate overall survival (OS) and disease-free survival (DFS) with SR and RS for different cancer types and simulate the plausibility of RS- and SR-induced antitumor immunity contributing to outcomes.

MATERIALS AND METHODS

We analyzed a SEER data set of early-stage cancers treated with SR or RS. OS and DFS were calculated for cancers with sufficient numbers for statistical power (cancers of lung and bronchus, esophagus, rectum, cervix uteri, corpus uteri, and breast). We simulated the immunologic consequences of SR, RS, and radiotherapy alone in a mathematical model of tumor-immune interactions.

RESULTS

RS improved OS for cancers with low 20-year survival rates (lung: hazard ratio [HR], 0.88; P = .046) and improved DFS for cancers with higher survival (breast: HR = 0.64; P < .001). For rectal cancer, with intermediate 20-year survival, RS improved both OS (HR = 0.89; P = .006) and DFS (HR = 0.86; P = .04). Model simulations suggested that RS could increase OS by eliminating cancer for a broader range of model parameters and radiotherapy-induced antitumor immunity compared with SR for selected parameter combinations. This could create an immune memory that may explain increased DFS after RS for certain cancers.

CONCLUSION

Study results suggest plausibility that radiation to the bulk of the tumor could induce a more robust immune response and better harness the synergy of radiotherapy and antitumor immunity than postsurgical radiation to the tumor bed. This exploratory study provides motivation for prospective evaluation of immune activation of RS versus SR in controlled clinical studies.

The Utility of Liquid Biopsies in Radiation Oncology

The use of therapeutic radiation is primarily guided by clinicopathologic factors and medical imaging, whereas molecular biomarkers currently play a comparatively minor role in most settings. Liquid biopsies provide a rich source of noninvasive tumor-specific biomarkers and are amenable to repeated and noninvasive assessment. Here, we review the current status of liquid biopsies and their potential impact on the field of radiation oncology. We focus on established and emerging approaches to analyze circulating tumor DNA and circulating tumor cells from peripheral blood. These promising classes of biomarkers could have an outsized impact on cancer management by meaningfully stratifying patients into risk groups, tracking radiation therapy efficacy during and after treatment, and identifying patients with radiosensitive or radioresistant disease. Finally, we highlight opportunities for future investigation including the need for prospective interventional studies employing liquid biopsies to guide the management of radiation therapy-treated patients.

Neoadjuvant Radio(chemo)therapy for Breast Cancer: An Old Concept Revisited

Background: The international standard of care for the treatment of high-risk breast cancer (BC) consists of neoadjuvant chemotherapy (NACT) and surgery followed by adjuvant whole breast/chest wall irradiation. In this setting, the time interval from the start of NACT to the end of radiotherapy (RT) is usually postponed to 6 months or longer. In addition to this, a high percentage of capsular fibrosis may occur when breast implants are irradiated. Most of these disadvantages could be avoided by using preoperative RT (PRT). PRT is already the standard of care in several other tumor entities (rectal cancer, esophagus carcinoma, lung cancer, and soft tissue sarcoma). Nevertheless, PRT in BC has been tested in several trials, but randomized prospective trials using modern radiation technology and systemic therapies are lacking. The available evidence summarized in this review indicates that PRT may improve survival and reduce long-term toxicity in patients with a higher risk of recurrence and should be consequently tested in a randomized trial. Summary: Prospective, randomized trials concerning PRT in high-risk BC are needed. We plan to conduct a NeoRad trial (NACT followed by PRT in high-risk BC). Key Messages: Prospective, randomized studies concerning PRT in high-risk BC are needed.

A Novel Electrochemiluminescent Immunoassay Based on Target Transformation Assisted with Catalyzed Hairpin Assembly Amplification for the Ultrasensitive Bioassay

In this work, we constructed a novel electrochemiluminescent (ECL) strategy based on sandwich immunoassay-induced target transformation assisted with catalyzed hairpin assembly (CHA) amplification for ultrasensitive bioassay with cysteine-rich protein 61 (CCN1) as a model. First, the target CCN1 could be equally transformed into the specific oligonucleotide (initiator I) labeled on the detection antibody based on the specific sandwich immunoassay. In addition, the initiator I triggered an efficient nonenzymatic CHA amplification in the presence of ferrocene-labeled hairpin 1 (Fc-H1) and hairpin 2 (H2) to produce massive hybrids (Fc-H1-H2) containing a sticky end labeled with ferrocene. Finally, Fc-H1-H2 could be immobilized on the capture probe single-stranded DNA (ssDNA)-modified electrode through the hybridization between the sticky end of Fc-H1-H2 and ssDNA, and a significantly quenched ECL signal could be obtained due to the efficient quench effect between ferrocene and the ECL indicator, ruthenium(II) tris(4,4'-dicarboxylicacid-2,2'-bipyridyl) [Ru(dcbpy)₃²⁺], immobilized on the surface of the electrode, which was related to the concentration of target CCN1. As expected, the proposed ECL biosensor exhibited a relatively low detection limit of 3.9 fg/mL in a linear range from 10 fg/mL to 100 ng/mL. This ECL strategy inspired the clinical examination of the biomarker CCN1, providing potential application in early diagnosis and malignant monitoring of cancer.

Dosimetric comparison between three- and four-dimensional computerised tomography radiotherapy for breast cancer

At present, methods of radiotherapy simulation for breast cancer based on four-dimensional computerised tomography (4D-CT) or three-dimensional CT (3D-CT) simulation remain controversial. In the present study, 7 patients with residual breast tissue received whole breast radiotherapy based on 3D-CT and 4D-CT simulation. For the 4D-CT plan, four types of CT images were produced, including images of the end of inspiration and the end of expiration, and images acquired by the maximal intensity projection (MIP) and average intensity projection (AIP). In the 3D-CT plan, the clinical target volume (CTV) and plan target volume (PTV) were marginally higher compared with the 4D-CT plan. In addition, the minimum point dose of the target volume (D min), the maximum point dose of the target volume (D max) and the mean point dose of the target volume (D mean) of the CTV and PTV in the MIP and AIP plans were marginally higher compared with the 3D-CT plan. For the contralateral breast (C-B), volumes of the 4D-CT plan were markedly lower compared with the 3D-CT plan. Furthermore, D min, D max and D mean of the 3D-CT plan were higher compared with the AIP and MIP plans. For the ipsilateral lungs (I-L), volumes of the 3D-CT and AIP plans were higher compared with the MIP plan. Furthermore, when breast lesions were on the left side, for the heart, the volume receiving no less than 40% of the prescription dose (V 40) and the volume receiving no less than 30% of the prescription dose (V 30) of the MIP and AIP plans were slightly lower compared with those of the 3D plan. In conclusion, 4D-CT radiotherapy based on the MIP and AIP plans provides a slightly smaller radiation area and slightly higher radiotherapy dosage of the CTV and PTV compared with 3D-CT radiotherapy for breast radiotherapy. Therefore, the MIP and AIP plans prevent C-B radiation exposure and improve sparing of the heart and I-L.

The 2019 mathematical oncology roadmap

Whether the nom de guerre is Mathematical Oncology, Computational or Systems Biology, Theoretical Biology, Evolutionary Oncology, Bioinformatics, or simply Basic Science, there is no denying that mathematics continues to play an increasingly prominent role in cancer research. Mathematical Oncology-defined here simply as the use of mathematics in cancer research-complements and overlaps with a number of other fields that rely on mathematics as a core methodology. As a result, Mathematical Oncology has a broad scope, ranging from theoretical studies to clinical trials designed with mathematical models. This Roadmap differentiates Mathematical Oncology from related fields and demonstrates specific areas of focus within this unique field of research. The dominant theme of this Roadmap is the personalization of medicine through mathematics, modelling, and simulation. This is achieved through the use of patient-specific clinical data to: develop individualized screening strategies to detect cancer earlier; make predictions of response to therapy; design adaptive, patient-specific treatment plans to overcome therapy resistance; and establish domain-specific standards to share model predictions and to make models and simulations reproducible. The cover art for this Roadmap was chosen as an apt metaphor for the beautiful, strange, and evolving relationship between mathematics and cancer.

Preoperative radiotherapy: A paradigm shift in the treatment of breast cancer? A review of literature

The standard of care for early-stage breast cancer (BC) consists of breast-conserving surgery followed by postoperative irradiation. Recently, the concept of changing the usual sequence of treatment components in BC RT has been investigated. Potential advantages of preoperative RT in BC include a possible tumor downstaging with improved surgical cosmetic outcomes, accurate tumor site identification and better target volume delineation. Furthermore, preoperative RT could serve as a tool for treatment stratification for de-escalation of treatments in the event of pathological complete response. The present literature review analyzed the available clinical data regarding the potential impact of preoperative RT. Overall, available clinical evidence of preoperative RT in BC remains limited, deriving mostly from retrospective case series. Nevertheless, the experiences prove the feasibility of the preoperative RT approach and confirm the efficacy in almost all analyzed studies, including experiences using higher prescription RT doses or RT in combination with systemic therapy.