A randomised study of whole-breast vs tumour-bed irradiation after local excision and axillary dissection for early breast cancer

Partial breast irradiation compared with whole breast irradiation: a systematic review and meta-analysis

BACKGROUND

Early-stage breast cancer is among the most common cancer diagnoses. Adjuvant radiotherapy is an essential component of breast-conserving therapy, and several options exist for tailoring its extent and duration. This study assesses the comparative effectiveness of partial-breast irradiation (PBI) compared with whole-breast irradiation (WBI).

METHODS

A systematic review was completed to identify relevant randomized clinical trials and comparative observational studies. Independent reviewers working in pairs selected studies and extracted data. Randomized trial results were pooled using a random effects model. Prespecified main outcomes were ipsilateral breast recurrence (IBR), cosmesis, and adverse events (AEs).

RESULTS

Fourteen randomized clinical trials and 6 comparative observational studies with 17 234 patients evaluated the comparative effectiveness of PBI. PBI was not statistically significantly different from WBI for IBR at 5 years (RR = 1.34, 95% CI = 0.83 to 2.18; high strength of evidence [SOE]) and 10 years (RR = 1.29, 95% CI = 0.87 to 1.91; high SOE). Evidence for cosmetic outcomes was insufficient. Statistically significantly fewer acute AEs were reported with PBI compared with WBI, with no statistically significant difference in late AEs. Data from subgroups according to patient, tumor, and treatment characteristics were insufficient. Intraoperative radiotherapy was associated with higher IBR at 5, 10, and over than 10 years (high SOE) compared with WBI.

CONCLUSIONS

Ipsilateral breast recurrence was not statistically significantly different between PBI and WBI. Acute AEs were less frequent with PBI. This evidence supports the effectiveness of PBI among selected patients with early-stage, favorable-risk breast cancer who are similar to those represented in the included studies.

A Meta-Analysis of Trials of Partial Breast Irradiation

PURPOSE

Partial breast irradiation (PBI) is the delivery of radiation therapy (RT) limited to the tumor bed after breast conserving surgery. The results of recent trials of PBI compared with whole breast irradiation (WBI) have suggested conflicting results with respect to local control and toxicity. The purpose of this meta-analysis was to assess effectiveness of PBI and to compare the different techniques.

METHODS AND MATERIALS

A meta-analysis of aggregate data from published randomized trials was performed to examine the effectiveness of PBI compared with WBI in patients with invasive breast cancer and ductal carcinoma in situ. Relevant data were extracted. The primary outcome was any ipsilateral breast event (invasive or noninvasive). Secondary outcomes included acute and late toxicity. The results of randomized trials were pooled using a fixed effects model and the inverse variance method.

RESULTS

Fifteen trials involving 16,474 patients were identified. The majority of enrolled patients were >60 years of age and had T1N0 grade 1 to 2 disease treated with hormone therapy. The percent of ipsilateral breast events was higher in patients treated with PBI compared with WBI (5.0% vs 2.8%; risk ratio [RR], 1.72; 95% confidence interval [CI], 1.47-2.02). Heterogeneity (P = .0002) was observed between the 4 PBI techniques: external beam RT without computed tomography (CT) planning (RR, 2.06; 95% CI, 1.36-3.12); brachytherapy (RR, 1.21; 95% CI, 0.65-2.25); intraoperative RT (RR, 2.79; 95% CI, 2.08-3.73); and external beam RT with CT planning (RR, 1.25; 95% CI, 0.99-1.58). When external beam RT without CT planning and intraoperative RT trials were excluded, the percent of ipsilateral breast events was 3.3% versus 2.6%, respectively (RR, 1.25; 95% CI, 1.00-1.55; P = .05), and no heterogeneity was observed (P = .92). Overall, acute toxicity was less with PBI, and the effect on late toxicity varied by technique.

CONCLUSIONS

Overall, WBI was more effective than PBI, but the effectiveness of PBI was technique related. PBI was less effective when given by external beam RT without CT planning or intraoperative therapy. Although PBI given by multicatheter brachytherapy or external beam RT with CT planning tended to be statistically less effective than WBI, the absolute difference between groups for ipsilateral breast events was very small (<1%), supporting these approaches for women considering PBI.

Partial breast irradiation versus whole breast radiotherapy for early breast cancer

BACKGROUND

Breast-conserving therapy for women with breast cancer consists of local excision of the tumour (achieving clear margins) followed by radiotherapy (RT). Most true recurrences occur in the same quadrant as the original tumour. Whole breast radiotherapy (WBRT) may not protect against the development of a new primary cancer developing in other quadrants of the breast. In this Cochrane Review, we investigated the delivery of radiation to a limited volume of the breast around the tumour bed (partial breast irradiation (PBI)) sometimes with a shortened treatment duration (accelerated partial breast irradiation (APBI)).

OBJECTIVES

To determine whether PBI/APBI is equivalent to or better than conventional or hypofractionated WBRT after breast-conserving therapy for early-stage breast cancer.

SEARCH METHODS

On 27 August 2020, we searched the Cochrane Breast Cancer Group Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and three trial databases. We searched for grey literature: OpenGrey (September 2020), reference lists of articles, conference proceedings and published abstracts, and applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) without confounding, that evaluated conservative surgery plus PBI/APBI versus conservative surgery plus WBRT. Published and unpublished trials were eligible.

DATA COLLECTION AND ANALYSIS

Two review authors (BH and ML) performed data extraction, used Cochrane's risk of bias tool and resolved any disagreements through discussion, and assessed the certainty of the evidence for main outcomes using GRADE. Main outcomes were local recurrence-free survival, cosmesis, overall survival, toxicity (subcutaneous fibrosis), cause-specific survival, distant metastasis-free survival and subsequent mastectomy. We entered data into Review Manager 5 for analysis.

MAIN RESULTS

We included nine RCTs that enrolled 15,187 women who had invasive breast cancer or ductal carcinoma in-situ (6.3%) with T1-2N0-1M0 Grade I or II unifocal tumours (less than 2 cm or 3 cm or less) treated with breast-conserving therapy with negative margins. This is the second update of the review and includes two new studies and 4432 more participants. Local recurrence-free survival is probably slightly reduced (by 3/1000, 95% CI 6 fewer to 0 fewer) with the use of PBI/APBI compared to WBRT (hazard ratio (HR) 1.21, 95% confidence interval (CI) 1.03 to 1.42; 8 studies, 13,168 participants; moderate-certainty evidence). Cosmesis (physician/nurse-reported) is probably worse (by 63/1000, 95% CI 35 more to 92 more) with the use of PBI/APBI (odds ratio (OR) 1.57, 95% CI 1.31 to 1.87; 6 studies, 3652 participants; moderate-certainty evidence). Overall survival is similar (0/1000 fewer, 95% CI 6 fewer to 6 more) with PBI/APBI and WBRT (HR 0.99, 95% CI 0.88 to 1.12; 8 studies, 13,175 participants; high-certainty evidence). Late radiation toxicity (subcutaneous fibrosis) is probably increased (by 14/1000 more, 95% CI 102 more to 188 more) with PBI/APBI (OR 5.07, 95% CI 3.81 to 6.74; 2 studies, 3011 participants; moderate-certainty evidence). The use of PBI/APBI probably makes little difference (1/1000 less, 95% CI 6 fewer to 3 more) to cause-specific survival (HR 1.06, 95% CI 0.83 to 1.36; 7 studies, 9865 participants; moderate-certainty evidence). We found the use of PBI/APBI compared with WBRT probably makes little or no difference (1/1000 fewer (95% CI 4 fewer to 6 more)) to distant metastasis-free survival (HR 0.95, 95% CI 0.80 to 1.13; 7 studies, 11,033 participants; moderate-certainty evidence). We found the use of PBI/APBI in comparison with WBRT makes little or no difference (2/1000 fewer, 95% CI 20 fewer to 20 more) to mastectomy rates (OR 0.98, 95% CI 0.78 to 1.23; 3 studies, 3740 participants, high-certainty evidence).

AUTHORS' CONCLUSIONS

It appeared that local recurrence-free survival is probably worse with PBI/APBI; however, the difference was small and nearly all women remain free of local recurrence. Overall survival is similar with PBI/APBI and WBRT, and we found little to no difference in other oncological outcomes. Some late effects (subcutaneous fibrosis) may be worse with PBI/APBI and its use is probably associated with worse cosmetic outcomes. The limitations of the data currently available mean that we cannot make definitive conclusions about the efficacy and safety or ways to deliver PBI/APBI. We await completion of ongoing trials.

Comparison between Accelerated Partial Breast Irradiation with multicatheter interstitial brachytherapy and Whole Breast Irradiation, in clinical practice

Purpose

The aim of this study was to compare accelerated partial breast irradiation (APBI) with multicatheter interstitial brachytherapy (BT) and whole breast irradiation (WBI), in terms of toxicity, aesthetic result, quality of life and survival, in clinical practice.

Materials and methods

A comparative study of two prospectively recorded cohorts of 76 breast cancer patients who complied with the recommendations of GEC-ESTRO for APBI was conducted. The main objective was toxicity, quality of life measured through validated questionnaires and the aesthetic results. Secondary objectives were overall survival and disease-free survival.

Results

Seventy-six stage I/II breast cancer patients, with a mean age of 66 years entered the study. APBI group showed less acute G1-2 dermatitis (51.4 vs 94.9%, p < 0.001) and late hyperpigmentation (0 vs 17.9%, p = 0.04). There were no differences in aesthetic results, both assessed by the patient herself and by the doctor. Statistically significant differences in measures of quality of life were observed in favour of the APBI, both in EORTC QLQ-BR23 and body image scale questionnaires. With a median follow-up of 72 months (6 years), the estimated overall survival at 5 and 10 years was 96.8 and 77.7%, respectively, and disease-free survival at 5 and 10 years was 91.1 and 69.4%, respectively, without statistically significant differences between groups.

Discussion

APBI is an attractive alternative in candidate patients with initial breast cancer, with benefits in acute toxicity and quality of life and fewer visits to the hospital, without compromising tumor control or survival.

Single-dose intraoperative radiotherapy during lumpectomy for breast cancer: an innovative patient-centred treatment

In the randomised TARGIT-A trial, risk-adapted targeted intraoperative radiotherapy (TARGIT-IORT) during lumpectomy was non-inferior to whole-breast external beam radiotherapy, for local recurrence. In the long-term, no difference was found in any breast cancer outcome, whereas there were fewer deaths from non-breast-cancer causes. TARGIT-IORT should be included in pre-operative consultations with eligible patients.

Who are the optimal candidates for partial breast irradiation?

At the 2017 St. Gallen International Expert Consensus Conference on the Primary Therapy for Early Breast Cancer, the consensus panel recognized "partial breast irradiation as an option for women meeting the low-risk criteria put forward by the American Society for Radiation Oncology/European Society for Radiotherapy and Oncology (ASTRO/ESTRO) guideline," although acknowledging that there was less evidence for this approach. Partial breast irradiation is defined as irradiation localized to the surgical resection cavity only as opposed to the entire breast. Accelerated partial breast irradiation (APBI) involves intensive treatment in a short time period. The methods vary, and three available APBI options are brachytherapy, external beam and intra-operative irradiation. The long-term follow-up results from two large-scale, well-designed phase III randomized clinical trials have been released. However, further discussion of the optimal treatment candidates and delivery method is needed before the clinical application of APBI as a mainstream breast conservation treatment.

Long term survival and local control outcomes from single dose targeted intraoperative radiotherapy during lumpectomy (TARGIT-IORT) for early breast cancer: TARGIT-A randomised clinical trial

OBJECTIVE

To determine whether risk adapted intraoperative radiotherapy, delivered as a single dose during lumpectomy, can effectively replace postoperative whole breast external beam radiotherapy for early breast cancer.

DESIGN

Prospective, open label, randomised controlled clinical trial.

SETTING

32 centres in 10 countries in the United Kingdom, Europe, Australia, the United States, and Canada.

PARTICIPANTS

2298 women aged 45 years and older with invasive ductal carcinoma up to 3.5 cm in size, cN0-N1, eligible for breast conservation and randomised before lumpectomy (1:1 ratio, blocks stratified by centre) to either risk adapted targeted intraoperative radiotherapy (TARGIT-IORT) or external beam radiotherapy (EBRT).

INTERVENTIONS

Random allocation was to the EBRT arm, which consisted of a standard daily fractionated course (three to six weeks) of whole breast radiotherapy, or the TARGIT-IORT arm. TARGIT-IORT was given immediately after lumpectomy under the same anaesthetic and was the only radiotherapy for most patients (around 80%). TARGIT-IORT was supplemented by EBRT when postoperative histopathology found unsuspected higher risk factors (around 20% of patients).

MAIN OUTCOME MEASURES

Non-inferiority with a margin of 2.5% for the absolute difference between the five year local recurrence rates of the two arms, and long term survival outcomes.

RESULTS

Between 24 March 2000 and 25 June 2012, 1140 patients were randomised to TARGIT-IORT and 1158 to EBRT. TARGIT-IORT was non-inferior to EBRT: the local recurrence risk at five year complete follow-up was 2.11% for TARGIT-IORT compared with 0.95% for EBRT (difference 1.16%, 90% confidence interval 0.32 to 1.99). In the first five years, 13 additional local recurrences were reported (24/1140 v 11/1158) but 14 fewer deaths (42/1140 v 56/1158) for TARGIT-IORT compared with EBRT. With long term follow-up (median 8.6 years, maximum 18.90 years, interquartile range 7.0-10.6) no statistically significant difference was found for local recurrence-free survival (hazard ratio 1.13, 95% confidence interval 0.91 to 1.41, P=0.28), mastectomy-free survival (0.96, 0.78 to 1.19, P=0.74), distant disease-free survival (0.88, 0.69 to 1.12, P=0.30), overall survival (0.82, 0.63 to 1.05, P=0.13), and breast cancer mortality (1.12, 0.78 to 1.60, P=0.54). Mortality from other causes was significantly lower (0.59, 0.40 to 0.86, P=0.005).

CONCLUSION

For patients with early breast cancer who met our trial selection criteria, risk adapted immediate single dose TARGIT-IORT during lumpectomy was an effective alternative to EBRT, with comparable long term efficacy for cancer control and lower non-breast cancer mortality. TARGIT-IORT should be discussed with eligible patients when breast conserving surgery is planned.

TRIAL REGISTRATION

ISRCTN34086741, NCT00983684.

Partial-breast irradiation versus whole-breast radiotherapy for early breast cancer: A systematic review and update meta-analysis

PURPOSE

The purpose of this study was to compare the treatment outcomes of partial-breast irradiation (PBI) versus whole-breast radiotherapy (WBRT) in early breast cancer.

METHODS AND MATERIALS

Eligible randomized clinical trials were identified on Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through December 2019. A meta-analysis for local recurrence (LR), overall mortality (OM), and non-breast cancer mortality (NBCM) was conducted. When possible, the outcomes were calculated for 5, 7, and 10 years of followup. A subgroup analysis by PBI technique (brachytherapy [BT], external beam radiotherapy [EBRT], intraoperative radiotherapy [IORT], and mixed) was performed. A p value < 0.05 was considered significant.

RESULTS

Eleven randomized clinical trials with a total of 14,436 patients (7186 PBI vs. 7250 WBRT) were included in the meta-analysis. The odds ratio (OR) for LR in 5 y was 1.46 (95% CI 1.15-2, p = 0.024) for PBI. In the subgroup analysis, no significant difference for LR was observed between PBI and WBRT using BT (p = 0.51), EBRT (p = 0.25), or mixed techniques (p = 0.89). The only subgroup with statistical difference was IORT 3.1 (95% CI 1.2-7.6, p = 0.014). No significant difference in LR was observed with 7 and 10 years among the groups. The OM had no difference at 5, 7, and 10 years of followup for any subgroup. A nonsignificant difference was observed comparing PBI with WBRT for NBCM OR = 1.24 (95% CI 0.98-1.57, p = 0.07). The rates of cardiac death, contralateral breast cancer, and development of second tumor were not significant.

CONCLUSIONS

The LR with PBI is low and similar to WBRT in selected early breast cancer with a longer followup. The subgroup analysis detected a significant difference for LR associated with IORT and no significant difference for BT and EBRT. Our results confirm a nonsignificant difference for OM and NBCM between PBI and WBRT.

Accelerated Partial Breast Irradiation: A New Standard of Care?

Background

Breast-conserving therapy including lumpectomy and adjuvant whole breast irradiation (WBI) has become the standard therapy for early-stage breast cancer (EBC). Without WBI, the recurrence rate is significantly increased. However, when selecting patients at a low a priori risk of local recurrence only a small breast-cancer-specific mortality benefit, but no overall survival improvement, was detected for WBI. As most recurrences occur close to the lumpectomy cavity, accelerated partial breast irradiation (APBI) delivered exclusively to a limited volume of tissue around the initial lumpectomy site, has gained increased attention and is now discussed as an alternative to WBI for selected EBC patients.

Summary

Numerous techniques for APBI (interstitial brachytherapy, external beam-based APBI, intraoperative radiotherapy, MR-guided radiotherapy) allow treatment delivery in a shorter period of time, and radiation oncologists expect to further reduce side effects by using these new techniques, with improvements in cosmetics and quality of life. In this review, we aim to describe the existing evidence for the feasibility and effectiveness of different APBI techniques used in modern radiotherapy.

Key Messages

APBI has provided outcomes similar to WBI combined with potentially reduced toxicity. While appropriate patient selection persists to be crucial for acceptable recurrence rates, the precise definition of patients suitable for APBI remains a matter of discussion. As long-term data are often still lacking, special attention should be paid to late side effects and long-term outcomes. Decision-making on appropriate treatment techniques should take into account not only local control rates, but also the impact on the patient's quality of life.

The evolution of adjuvant radiation therapy for early-stage and locally advanced breast cancer

Adjuvant radiation therapy is often delivered after breast cancer surgery, both in the post-lumpectomy and post-mastectomy settings. Standard fractionation whole breast irradiation (SF-WBI), which is typically delivered over 5-7 weeks, was previously considered the standard of care. More recent data has helped to establish hypofractionated whole breast irradiation (HF-WBI), which consists of a 3-4 week regimen, as a new standard of care. This article provides an overview of the major randomized trials that support the routine use of HF-WBI for the majority of patients undergoing breast-conserving surgery for early-stage breast cancer. Newer data on the use of a hypofractionated approach in the post-mastectomy setting, as well as ongoing randomized trials addressing this topic, are also discussed.

Individualised target volume selection and dose prescription after conservative surgery, mastectomy and reconstruction

Progress in radiotherapy (RT) for early breast cancer, driven by advances in radiobiology and radiation techniques is enabling individualised target volume and dose-fractionation according to recurrence risk. Conventionally fractionated WBI (CF-WBI) has been justified on the basis that it spares dose-limiting late-responding normal tissues more than breast cancer. However, randomised clinical trials (RCTs) testing hypofractionated WBI (HF-WBI) showed equivalent tumour control, improved acute toxicity and similar late toxicity between selected HF-WBI schedules and CF-WBI. RCTs showed that tumour bed boost (TBB) after WBI improved local control but increased breast fibrosis compared to no TBB. RCT comparing sequential TBB and simultaneous integrated TBB using dose intensity modulation showed similar toxicity. Partial breast irradiation (PBI) limits target volume to the tumour bed, which permits safe treatment acceleration. RCTs showed that PBI resulted in low local relapse rates but in some RCTs, higher rates of late toxicity and adverse cosmetic outcome than WBI. Given heterogeneity of PBI techniques, target volumes and dose-fractionation schedules used in RCTs, interpretation of results to distinguish whether outcome variations are caused by target volume or dose-fractionation effect is challenging. RCTs demonstrating efficacy of post-mastectomy RT (PMRT) included the chest wall and regional nodes but did not distinguish relative contributions of nodal target sub-volumes. In patients with smaller axillary tumour burden, IMC irradiation is controversial. RCTs were not powered for comparison between CF-PMRT and HF-PMRT. No increase in arm or shoulder dysfunction with HF-PMRT was observed. No RCT data exist on HF-PMRT in patients with breast reconstruction.

Effectiveness of different accelerated partial breast irradiation techniques for the treatment of breast cancer patients: Systematic review using indirect comparisons of randomized clinical trials

AIM

This systematic review was conducted to compare the effectiveness of different accelerated partial breast irradiation (APBI) techniques for the treatment of breast cancer patients.

BACKGROUND

Numerous (APBI) techniques are available for clinical practice.

METHODS AND MATERIALS

Systematic review of randomized controlled trials of APBI versus whole breast irradiation (WBI). The data from APBI studies were extracted for the analyses. Indirect comparisons were used to compare different APBI techniques.

RESULTS

Ten studies fulfilled the inclusion criteria. A total of 4343 patients were included, most of them with tumor stage T1-T2 and N0. Regarding APBI techniques, six trials used external beam radiation therapy; one intraoperative electrons; one intraoperative low-energy photons; one brachytherapy; and one external beam radiation therapy or brachytherapy. The indirect comparisons related to 5-years local control and 5-years overall survival were not significantly different between APBI techniques.

CONCLUSIONS

Based on indirect comparisons, no differences in clinical outcomes were observed among diverse APBI techniques in published clinical trials that formally compared WBI to APBI. However wide confidence intervals and high risk of inconsistency precluded a sound conclusion. Further head-to-head clinical trials comparing different APBI techniques are required to confirm our findings. Studies comparing different techniques using individual participant data and/or real-life data from population-based studies/registries could also provide more robust results.

Accelerated partial breast radiotherapy: a review of the literature and future directions

Breast conservation therapy exemplifies the tailoring of medicine in the care of patients with cancer. Akin to improvements in surgical approaches, accelerated partial breast irradiation (APBI) tailors the treatment volume and duration to the needs of well selected patients. Here, we examine the evidence supporting APBI as well as the lessons in patient selection, dose and delivery techniques. Examination of historical techniques and their associated outcomes will support more correct patient selection and treatment delivery in an era where we await the reports of several large prospective trials.

Alternatives to Standard Fractionation Radiation Therapy After Lumpectomy: Hypofractionated Whole-Breast Irradiation and Accelerated Partial-Breast Irradiation

Adjuvant whole-breast irradiation (WBI) after lumpectomy has been an established standard of care for decades. Standard-fractionation WBI delivered over 5 to 7 weeks can achieve durable tumor control with low toxicity but can be inconvenient for patients and cost ineffective. Hypofractionated WBI can be completed in 3 to 4 weeks and, based on long-term randomized data, is the preferred standard of care in select patients. Accelerated partial-breast irradiation can be delivered using even shorter treatment regimens. Although the available data on accelerated partial-breast irradiation is more limited, early results suggest it is an effective alternative to WBI in select patients.

Secondary malignancies after partial versus whole breast irradiation: a systematic review and meta-analysis

Secondary malignancies are a common complication for patients receiving radiotherapy. Here, we compared rates of secondary malignancies after partial breast irradiation (PBI) and whole breast irradiation (WBI). The MEDLINE, EMBASE, and the Cochrane Library databases were systematically searched to identify relevant randomized clinical trials comparing PBI with WBI in breast cancer patients treated with breast-conserving therapy. Four studies including 2,185 patients were selected. Compared to WBI, the pooled odds ratios (OR) for contralateral breast cancer were 0.86 (95% confidence interval (CI) 0.31–2.42; p = 0.78) after 5 years and 1.15 (95% CI 0.43-3.09; p = 0.78) after 10 years for PBI. The pooled ORs for secondary non-breast cancer were 0.91 (95% CI 0.49-1.67; p = 0.77) after 5 years and 1.20 (95% CI 0.39-3.66; p = 0.75) after 10 years for PBI compared to WBI. These results demonstrate that the risk of secondary malignancies is similar for PBI and WBI after breast-conserving radiotherapy.

Treatment constraints for single dose external beam preoperative partial breast irradiation in early-stage breast cancer

Background

Following breast-conserving surgery and post-operative 3D-conformal accelerated partial breast irradiation (APBI), suboptimal cosmetic results have been reported. Preoperative radiation delivery to the intact tumor enables better target visualization and treatment volume reduction. Single dose preoperative APBI has the potential to improve toxicity profiles, reduce treatment burden and enable in vivo exploration of breast cancer radiogenomics.

Purpose

Develop practical guidelines for single dose external beam preoperative APBI.

Methods

Recommended dose constraints were derived from pooled dosimetry estimates from 2 clinical trials. In an American dose escalation trial, a uniform 15, 18 or 21 Gy dose has previously been evaluated for non-lobular cT1N0 or low/intermediate grade DCIS <2 cm in prone position (n = 32). In the Netherlands, the feasibility of ablative APBI (20 Gy to GTV, 15 Gy to CTV) to non-lobular cT1N0 in supine position, is currently being explored (n = 15). The dosimetric adherence to the developed constraints was evaluated in new APBI plans with a 21 Gy uniform dose but an extended CTV margin (n = 32).

Results

Dosimetric data pooling enabled the development of practical guidelines for single dose preoperative APBI.

Conclusion

The developed guidelines will allow further explorations in the promising field of single dose preoperative external beam APBI for breast cancer treatment.

Efficacy and safety of accelerated partial breast irradiation: a meta-analysis of published randomized studies

Background and purpose

Accelerated partial breast irradiation (APBI) technology has theoretical advantages in comparison with traditional adjuvant radiation therapy (whole-breast irradiation; WBI) after breast-conserving surgery. However, published randomized controlled trials have shown inconsistent outcomes. Therefore, a comprehensive assessment of the effectiveness and safety of APBI technology is needed.

Results

A total of 7 studies of 7452 patients were included in this analysis. All 7 studies reported local recurrence as an outcome. Meta-analysis of 5 trials that included 6486 patients showed significantly different 5-year local recurrence rates for APBI and WBI groups (hazard ratio = 4.54, 95% confidence interval: 1.78–11.61, p = 0.002). Further analysis showed that this difference may be related to the choice of treatment methods. Benefit was conferred to the APBI group for the outcome of non-breast cancer deaths. There was no significant difference between the two groups in terms of nodal recurrence, systemic recurrence, overall survival, or mortality rates. Toxicity side effects and cosmetic effects were similar in both groups, but intraoperative radiotherapy seemed to have a greater acute response.

Material and methods

Searches for relevant randomized controlled trials of APBI versus WBI were performed using the following sources: PubMed, EMBASE, Cochrane Library, Web of Science. Two independent observers evaluated the identified studies. The meta-analysis was conducted using RevMan 5.2 software.

Conclusions

Although the analysis showed that patients receiving APBI had a higher local recurrence rate, subgroup analyses suggested that this might be related to treatment options. Patients who receive accurate radiotherapy may have greater benefits. APBI is a promising treatment technology and more phase III clinical trials are expected based on new treatments.

Restricted Axillary Staging in Clinically and Sonographically Node-Negative Early Invasive Breast Cancer (c/iT1-2) in the Context of Breast Conserving Therapy: First Results Following Commencement of the Intergroup-Sentinel-Mamma (INSEMA) Trial

Axillary lymph node status remains an important prognostic factor in early breast cancer. It is regarded as an indicator for (neo)adjuvant systemic treatment and postoperative radiotherapy of the regional lymphatics. Commenced in September 2015, the INSEMA trial is investigating whether operative determination of nodal status as part of breast conserving therapy (BCT) for early stage breast cancer (c/iT1-2 c/iN0) can be avoided without reducing oncological safety. After inclusion of 1001 patients there was general acceptance of the complex study design by patients and study doctors so that recruitment for the first randomisation (axillary sentinel lymph node biopsy [SLNB]: yes or no) achieved predicted case numbers. The second randomisation however (SLNB alone versus complete axillary dissection when one or two macrometastases are present at SLNB) recruited fewer cases than expected for the following three reasons: a) the 13 % rate of one or two macrometastases after SLNB in the INSEMA trial collective was lower than expected; b) around 20 % of patients refused the second randomisation; c) there was delayed inclusion of the Austrian study centres, which only recruited for the second randomisation. Lack of knowledge of nodal status when SLNB is avoided represents a new challenge for the postoperative tumour board. In particular decisions on chemotherapy for luminal-like tumours and irradiation of the lymphatics (excluding axilla) must be guided by tumour biological parameters. The INSEMA trial does not provide answers to some important questions, e.g. it remains unclear whether patients without SLNB can be offered partial breast irradiation alone in low-risk situations and whether SLNB can also be avoided in patients with stage T1-2 tumours who have a mastectomy indication.

Ipsilateral axillary recurrence after breast conservative surgery: The protective effect of whole breast radiotherapy

BACKGROUND AND PURPOSE

Whole breast radiotherapy (WBRT) is one of the possible reasons for the low rate of axillary recurrence after breast-conserving surgery (BCS).

PATIENTS AND METHODS

We retrospectively collected data from 4,129 consecutive patients with breast cancer ⩽2cm and negative sentinel lymph node who underwent BCS between 1997 and 2007. We compared the risk of axillary lymph node recurrence between patients treated by WBRT (n=2939) and patients who received partial breast irradiation (PBI; n=1,190) performed by a single dose of electron intraoperative radiotherapy.

RESULTS

Median tumour diameter was 1.1cm in both WBRT and PBI. Women who received WBRT were significantly younger and expressed significantly more multifocality, extensive in situ component, negative oestrogen receptor status and HER2 over-expression than women who received PBI. After a median follow-up of 8.3years, 37 and 28 axillary recurrences were observed in the WBRT and PBI arm, respectively, corresponding to a 10-year cumulative incidence of 1.3% and 4.0% (P<0.001). Multivariate analysis resulted in a hazard ratio of 0.30 (95% CI 0.17-0.51) in favour of WBRT.

CONCLUSIONS

In this large series of women with T1 breast cancer and negative sentinel lymph node treated by BCS, WBRT lowered the risk of axillary recurrence by two thirds as compared to PBI.

Over-irradiation

Decreasing the burden of radiation therapy (RT) for breast cancer includes, next to complete omission, several ways to tailor the extent of RT. Possible options for this include lowering of the total dose, such as selective omission of the boost, hypofractionated RT to shorten the duration of treatment, the selective introduction of partial breast irradiation and anatomy based target volume contouring to decrease the size of the irradiated volumes. Elective regional nodal irradiation showed in several randomised trials and meta-analyses to significantly impact on local-regional control, disease-free survival, breast cancer mortality and overall survival. The generalisability of these results remains complex in the light of the decreasing use of axillary lymph node dissection, the use of more effective adjuvant systemic therapy, the increasing use of primary systemic therapy and continuously improving RT techniques. In general, the use of RT compensates for the decreasing extent of surgery to the breast and the axillary lymph nodes, eliminating residual tumour cells while maintaining better aesthetic and functional results. In some occasions, however, the indications for the extent of RT have to be based on limited pathological staging information. Research is ongoing to individualise RT more on the basis of biological factors including gene expression profiles. When considering age, treatment decisions should rather be based on biological instead of formal age. The aim of this review article is to put current evidence into the right perspective, and to search for an appropriate appreciation of the balance between efficacy and side effects of local-regional RT.

Partial breast irradiation for early breast cancer

BACKGROUND

Breast-conserving therapy for women with breast cancer consists of local excision of the tumour (achieving clear margins) followed by radiotherapy (RT). RT is given to sterilize tumour cells that may remain after surgery to decrease the risk of local tumour recurrence. Most true recurrences occur in the same quadrant as the original tumour. Whole breast radiotherapy (WBRT) may not protect against the development of a new primary cancer developing in other quadrants of the breast. In this Cochrane review, we investigated the delivery of radiation to a limited volume of the breast around the tumour bed (partial breast irradiation (PBI)) sometimes with a shortened treatment duration (accelerated partial breast irradiation (APBI)).

OBJECTIVES

To determine whether PBI/APBI is equivalent to or better than conventional or hypo-fractionated WBRT after breast-conserving therapy for early-stage breast cancer.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group Specialized Register (4 May 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 5), MEDLINE (January 1966 to 4 May 2015), EMBASE (1980 to 4 May 2015), CINAHL (4 May 2015) and Current Contents (4 May 2015). We searched the International Standard Randomised Controlled Trial Number Register (5 May 2015), the World Health Organization's International Clinical Trials Registry Platform (4 May 2015) and ClinicalTrials.gov (17 June 2015). We searched for grey literature: OpenGrey (17 June 2015), reference lists of articles, several conference proceedings and published abstracts, and applied no language restrictions.

SELECTION CRITERIA

Randomized controlled trials (RCTs) without confounding, that evaluated conservative surgery plus PBI/APBI versus conservative surgery plus WBRT. Published and unpublished trials were eligible.

DATA COLLECTION AND ANALYSIS

Two review authors (BH and ML) performed data extraction and used Cochrane's 'Risk of bias' tool, and resolved any disagreements through discussion. We entered data into Review Manager 5 for analysis.

MAIN RESULTS

We included seven RCTs and studied 7586 women of the 8955 enrolled.Local recurrence-free survival appeared worse for women receiving PBI/APBI compared to WBRT (hazard ratio (HR) 1.62, 95% confidence interval (CI) 1.11 to 2.35; six studies, 6820 participants, low-quality evidence). Cosmesis (physician-reported) appeared worse with PBI/APBI (odds ratio (OR) 1.51, 95% CI 1.17 to 1.95, five studies, 1720 participants, low-quality evidence). Overall survival did not differ with PBI/APBI (HR 0.90, 95% CI 0.74 to 1.09, five studies, 6718 participants, high-quality evidence).Late radiation toxicity (subcutaneous fibrosis) appeared worse with PBI/APBI (OR 6.58, 95% CI 3.08 to 14.06, one study, 766 participants, moderate-quality evidence). Acute skin toxicity appeared reduced with PBI/APBI (OR 0.04, 95% CI 0.02 to 0.09, two studies, 608 participants). Telangiectasia (OR 26.56, 95% CI 3.59 to 196.51, 1 study, 766 participants) and radiological fat necrosis (OR 1.58, 95% CI 1.02 to 2.43, three studies, 1319 participants) appeared worse with PBI/APBI. Late skin toxicity (OR 0.21, 95% CI 0.01 to 4.39, two studies, 608 participants) and breast pain (OR 2.17, 95% CI 0.56 to 8.44, one study, 766 participants) appeared not to differ with PBI/APBI.'Elsewhere primaries' (new primaries in the ipsilateral breast) appeared more frequent with PBI/APBI (OR 3.97, 95% CI 1.51 to 10.41, three studies, 3009 participants).We found no clear evidence of a difference for the comparison of PBI/APBI with WBRT for the outcomes of: cause-specific survival (HR 1.08, 95% CI 0.73 to 1.58, five studies, 6718 participants, moderate-quality evidence), distant metastasis-free survival (HR 0.94, 95% CI 0.65 to 1.37, four studies, 3267 participants, moderate-quality evidence), relapse-free survival (HR 1.36, 95% CI 0.88 to 2.09, three studies, 3811 participants), loco-regional recurrence-free survival (HR 1.80, 95% CI 1.00 to 3.25, two studies, 3553 participants) or mastectomy rates (OR 1.20, 95% CI 0.77 to 1.87, three studies, 4817 participants, low-quality evidence). Compliance was met: more than 90% of the women in all studies received the RT they were assigned to receive. We found no data for the outcomes of costs, quality of life or consumer preference.

AUTHORS' CONCLUSIONS

It appeared that local recurrence and 'elsewhere primaries' (new primaries in the ipsilateral breast) are increased with PBI/APBI (the difference was small), but we found no evidence of detriment to other oncological outcomes. It appeared that cosmetic outcomes and some late effects were worse with PBI/APBI but its use was associated with less acute skin toxicity. The limitations of the data currently available mean that we cannot make definitive conclusions about the efficacy and safety or ways to deliver of PBI/APBI. We await completion of ongoing trials.

GEC-ESTRO multicenter phase 3-trial: Accelerated partial breast irradiation with interstitial multicatheter brachytherapy versus external beam whole breast irradiation: Early toxicity and patient compliance

BACKGROUND AND PURPOSE

To compare early side effects and patient compliance of accelerated partial breast irradiation (APBI) with multicatheter brachytherapy to external beam whole breast irradiation (WBI) in a low-risk group of patients with breast cancer.

MATERIAL AND METHODS

Between April 2004 and July 2009, 1328 patients with UICC stage 0-IIA breast cancer were randomized to receive WBI with 50Gy and a boost of 10Gy or APBI with either 32.0Gy/8 fractions, or 30.1Gy/7 fractions (HDR-brachytherapy), or 50Gy/0.60-0.80Gy per pulse (PDR-brachytherapy). This report focuses on early side-effects and patient compliance observed in 1186 analyzable patients. ClinicalTrials.gov identifier: NCT00402519.

RESULTS

Patient compliance was excellent in both arms. Both WBI and APBI were well tolerated with moderate early side-effects. No grade 4 toxicity had been observed. Grade 3 side effects were exclusively seen for early skin toxicity (radiation dermatitis) with 7% vs. 0.2% (p<0.0001), and breast infection with 0% vs. 0.2% (p=n.s.) for patients treated with WBI and APBI. The incidence of grades 1-2 early side effects for WBI and APBI was 86% vs. 21% (p<0.0001) for skin toxicity, 2% vs. 20% (p<0.0001) for mild hematoma, and 2% vs. 5% (p=0.01) for mild breast infection rates, respectively. No differences had been found regarding grades 1-2 early breast pain (26% vs. 29%, p=0.23).

CONCLUSIONS

APBI with interstitial multicatheter brachytherapy was tolerated very well and dramatically reduced early skin toxicity in comparison to standard WBI.

Reduced Mortality With Partial-Breast Irradiation for Early Breast Cancer: A Meta-Analysis of Randomized Trials

PURPOSE

With earlier detection and more effective treatment, mortality from breast cancer continues to fall and it has become increasingly important to reduce the toxicity of treatments. Partial-breast radiation therapy, which focuses radiation to the tumor bed, may achieve this aim. We analyzed mortality differences in randomized trials of partial-breast irradiation (PBI).

METHODS AND MATERIALS

We included data from published randomized trials of PBI (alone or as part of a risk-adapted approach) versus whole-breast irradiation (WBI) for invasive breast cancer suitable for breast-conserving therapy. We identified trials using PubMed and Google searches with the terms "partial breast irradiation" OR "intraoperative radiotherapy" OR "IMRT" OR ("accelerated" AND "radiation") AND "randomised/randomized," as well as through discussion with colleagues in the field. We calculated the proportion of patients who had events in each randomized arm at 5 years' follow-up and created a forest plot using Stata, version 14.1.

RESULTS

We identified 9 randomized trials of PBI versus WBI in invasive breast cancer; 5-year outcomes were available for non-breast cancer mortality in 5 trials (n=4489) and for breast cancer mortality in 4 trials (n=4231). The overall mortality was 4.9%. There was no detectable heterogeneity between the trials for any of the outcomes. There was no difference in the proportion of patients dying of breast cancer (difference, 0.000% [95% confidence interval (CI), -0.7 to +0.7]; P=.999). Non-breast cancer mortality with PBI was lower than with WBI (difference, 1.1% [95% CI, -2.1% to -0.2%]; P=.023). Total mortality with PBI was also lower than with WBI (difference, 1.3% [95% CI, -2.5% to 0.0%]; P=.05).

CONCLUSIONS

Use of PBI instead of WBI in selected patients results in a lower 5-year non-breast cancer and overall mortality, amounting to a 25% reduction in relative terms. This information should be included when breast-conserving therapy is proposed to a patient.

Accelerated partial breast irradiation: advances and controversies

The management of localized breast cancer has changed dramatically over the past three to four decades. Breast-conserving therapy, which involved lumpectomy followed by adjuvant irradiation, is now widely considered the standard of care in women with early-stage breast cancer. Accelerated partial breast irradiation (APBI), which involves focal irradiation of the lumpectomy cavity over a short period of time, has developed over the past two decades as an alternative to whole breast irradiation (WBI). Multiple APBI modalities have been developed including brachytherapy, external beam irradiation, and intraoperative irradiation. These new techniques have provided early-stage breast cancer patients with shorter treatment duration and more focused irradiation, delivering very high biological doses to the region at a high risk of failures over a much shorter treatment course as compared with conventional radiotherapy. However, the advantages of APBI over conventional radiotherapy are controversial, including a higher risk of complications reported in retrospective literature and shorter follow-up duration in the intraoperative APBI trials. Nevertheless, APBI presents a valuable alternative to WBI for a selected population of women with early-stage breast cancer.

5-year results of accelerated partial breast irradiation using sole interstitial multicatheter brachytherapy versus whole-breast irradiation with boost after breast-conserving surgery for low-risk invasive and in-situ carcinoma of the female breast: a randomised, phase 3, non-inferiority trial

BACKGROUND

In a phase 3, randomised, non-inferiority trial, accelerated partial breast irradiation (APBI) for patients with stage 0, I, and IIA breast cancer who underwent breast-conserving treatment was compared with whole-breast irradiation. Here, we present 5-year follow-up results.

METHODS

We did a phase 3, randomised, non-inferiority trial at 16 hospitals and medical centres in seven European countries. 1184 patients with low-risk invasive and ductal carcinoma in situ treated with breast-conserving surgery were centrally randomised to either whole-breast irradiation or APBI using multicatheter brachytherapy. The primary endpoint was local recurrence. Analysis was done according to treatment received. This trial is registered with ClinicalTrials.gov, number NCT00402519.

FINDINGS

Between April 20, 2004, and July 30, 2009, 551 patients had whole-breast irradiation with tumour-bed boost and 633 patients received APBI using interstitial multicatheter brachytherapy. At 5-year follow-up, nine patients treated with APBI and five patients receiving whole-breast irradiation had a local recurrence; the cumulative incidence of local recurrence was 1.44% (95% CI 0.51-2.38) with APBI and 0.92% (0.12-1.73) with whole-breast irradiation (difference 0.52%, 95% CI -0.72 to 1.75; p=0.42). No grade 4 late side-effects were reported. The 5-year risk of grade 2-3 late side-effects to the skin was 3.2% with APBI versus 5.7% with whole-breast irradiation (p=0.08), and 5-year risk of grade 2-3 subcutaneous tissue late side-effects was 7.6% versus 6.3% (p=0.53). The risk of severe (grade 3) fibrosis at 5 years was 0.2% with whole-breast irradiation and 0% with APBI (p=0.46).

INTERPRETATION

The difference between treatments was below the relevance margin of 3 percentage points. Therefore, adjuvant APBI using multicatheter brachytherapy after breast-conserving surgery in patients with early breast cancer is not inferior to adjuvant whole-breast irradiation with respect to 5-year local control, disease-free survival, and overall survival.

FUNDING

German Cancer Aid.

Accelerated partial breast irradiation using intensity-modulated radiotherapy versus whole breast irradiation: 5-year survival analysis of a phase 3 randomised controlled trial

BACKGROUND

Accelerated partial breast irradiation (APBI) has been introduced as an alternative treatment method for selected patients with early stage breast cancer (BC). Intensity-modulated radiotherapy (IMRT) has the theoretical advantage of a further increase in dose conformity compared with three-dimensional techniques, with more normal tissue sparing. The aim of this randomised trial is to compare the local recurrence and survival of APBI using the IMRT technique after breast-conserving surgery to conventional whole-breast irradiation (WBI) in early stage BC.

METHODS

This study was performed at the University of Florence (Florence, Italy). Women aged more than 40years affected by early BC, with a maximum pathological tumour size of 25mm, were randomly assigned in a 1:1 ratio to receive either WBI or APBI using IMRT. Patients in the APBI arm received a total dose of 30 Gy to the tumour bed in five daily fractions. The WBI arm received 50Gy in 25 fractions, followed by a boost on the tumour bed of 10Gy in five fractions. The primary end-point was occurrence of ipsilateral breast tumour recurrences (IBTRs); the main analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT02104895.

FINDINGS

A total of 520 patients were randomised (260 to external WBI and 260 to APBI with IMRT) between March 2005 and June 2013. At a median follow-up of 5.0 years (Interquartile Range (IQR) 3.4-7.0), the IBTR rate was 1.5% (three cases) in the APBI group (95% confidence interval (CI) 0.1-3.0) and in the WBI group (three cases; 95% CI 0.0-2.8). No significant difference emerged between the two groups (log rank test p=0.86). We identified seven deaths in the WBI group and only one in the APBI group (p=0.057). The 5-year overall survival was 96.6% for the WBI group and 99.4% for the APBI group. The APBI group presented significantly better results considering acute (p=0.0001), late (p=0.004), and cosmetic outcome (p=0.045).

INTERPRETATION

To our knowledge, this is the first randomised study using the IMRT technique for APBI delivery. No significant difference in terms of IBTR and overall survival was observed between the two arms. APBI displayed a significantly better toxicity profile.

Optimal management of breast cancer in the elderly patient: current perspectives

Breast cancer (BC) is the most common female malignancy in the world and almost one third of cases occur after 70 years of age. Optimal management of BC in the elderly is a real challenge and requires a multidisciplinary approach, mainly because the elderly population is heterogeneous. In this review, we describe the various possibilities of treatment for localized or metastatic BC in an aging population. We provide an overview of the comprehensive geriatric assessment, surgery, radiotherapy, and adjuvant therapy for early localized BC and of chemotherapy and targeted therapies for metastatic BC. Finally, we attempt to put into perspective the necessary balance between the expected benefits and risks, especially in the adjuvant setting.

Accelerated partial irradiation for breast cancer: systematic review and meta-analysis of 8653 women in eight randomized trials

BACKGROUND AND PURPOSE

Accelerated partial breast irradiation (APBI) is the strategy that allows adjuvant treatment delivery in a shorter period of time in smaller volumes. This study was undertaken to assess the effectiveness and outcomes of APBI in breast cancer compared with whole-breast irradiation (WBI).

MATERIAL AND METHODS

Systematic review and meta-analysis of randomized controlled trials of WBI versus APBI. Two authors independently selected and assessed the studies regarding eligibility criteria.

RESULTS

Eight studies were selected. A total of 8653 patients were randomly assigned for WBI versus APBI. Six studies reported local recurrence outcomes. Two studies were matched in 5 years and only one study for different time of follow-up. Meta-analysis of two trials assessing 1407 participants showed significant difference in the WBI versus APBI group regarding the 5-year local recurrence rate (HR=4.54, 95% CI: 1.78-11.61, p=0.002). Significant difference in favor of WBI for different follow-up times was also found. No differences in nodal recurrence, systemic recurrence, overall survival and mortality rates were observed.

CONCLUSIONS

APBI is associated with higher local recurrence compared to WBI without compromising other clinical outcomes.

[State of the art and perspectives of accelerated partial breast irradiation in 2014]

In the frame of treatment de-escalation and personalization, accelerated partial breast irradiation is taking its place in the breast cancer therapeutic options. This study analyzed the results of phase III randomized trials having compared accelerated partial breast irradiation versus whole breast irradiation. Currently, among those trails, six proposed some results regarding efficacy and/or toxicity. Globally, the non-randomized studies confirmed the expected results showing a low rate of local recurrence and toxicity. The first results of the phase III randomized trials showed encouraging data in terms of local control while the toxicity varied mainly according to the accelerated partial breast irradiation technique used. However, the follow-up of the majority of these studies remains insufficient. The strict respect of accelerated partial breast irradiation indications likely represents one of the key factors of the therapeutic success. The next results could allow proposing a better definition of the accelerated partial breast irradiation selection criteria.

Partial breast irradiation for early breast cancer

BACKGROUND

Breast conserving therapy for women with breast cancer consists of local excision of the tumour (achieving clear margins) followed by radiation therapy (RT). RT is given to sterilize tumour cells that may remain after surgery to decrease the risk of local tumour recurrence. Most true recurrences occur in the same quadrant as the original tumour. Whole breast RT may not protect against the development of a new primary cancer developing in other quadrants of the breast. In this Cochrane Review, we investigated the role of delivering radiation to a limited volume of the breast around the tumour bed (partial breast irradiation: PBI) sometimes with a shortened treatment duration (accelerated partial breast irradiation: APBI).

OBJECTIVES

To determine whether PBI/APBI is equivalent to or better than conventional or hypofractionated WBRT after breast conservation therapy for early-stage breast cancer.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group Specialised Register (07 November 2013), CENTRAL (2014, Issue 3), MEDLINE (January 1966 to 11 April 2014), EMBASE (1980 to 11 April 2014), CINAHL (11 April 2014) and Current Contents (11 April 2014). Also we searched the International Standard Randomised Controlled Trial Number Register, the World Health Organization's International Clinical Trials Registry Platform (07 November 2013) and US clinical trials registry (www.clinicaltrials.gov) (22 April 2014). We searched for grey literature: Open Grey (23 April 2014), reference lists of articles, a number of conference proceedings and published abstracts, and did not apply any language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) without confounding and evaluating conservative surgery plus PBI/APBI versus conservative surgery plus whole breast RT. We included both published and unpublished trials.

DATA COLLECTION AND ANALYSIS

Three review authors (ML, DF and BH) performed data extraction and resolved any disagreements through discussion. We entered data into Review Manager for analysis. BH and ML assessed trials, graded the methodological quality using Cochrane's Risk of Bias tool and resolved any disagreements through discussion.

MAIN RESULTS

We included four RCTs that had 2253 women. Two older trials examined RT techniques which do not reflect current practice and one trial had a short follow-up. We downgraded the quality of the evidence for our key outcomes due to risk of bias. Taken together with other GRADE recommendations, the quality of evidence for our outcomes was very low to low. For the comparison of partial breast irradiation/accelerated breast irradiation (PBI/APBI) with whole breast irradiation (WBRT), local recurrence-free survival appeared worse (Hazard Ratio (HR) 1.74, 95% confidence interval (CI) 1.23 to 2.45; three trials, 1140 participants, very low quality evidence). Cosmesis appeared improved with PBI/APBI in a single trial (OR 0.40, 95% CI 0.23 to 0.72; one trial, 241 participants, very low quality evidence), but late toxicity (telangiectasia OR 4.41, 95% CI 3.21 to 6.05; very low quality evidence, 708 participants) and subcutaneous fibrosis (OR 4.27, 95% CI 3.04 to 6.01; one trial, 710 participants, very low quality evidence) appeared increased in another trial. We found no clear evidence of a difference for the comparison of PBI/APBI versus WBRT for the outcomes of: overall survival (HR 0.99, 95% CI 0.83 to 1.18; three trials, 1140 participants, very low quality evidence), cause-specific survival (HR 0.95, 95% CI 0.74 to 1.22; two trials, 966 participants, low evidence quality), distant metastasis-free survival (HR 1.02, 95% CI 0.81 to 1.28; 1140 participants, low quality evidence), subsequent mastectomy rate (OR 0.20, 95% CI 0.01 to 4.21; 258 participants, low quality evidence) and relapse-free survival (HR 0.99, 95% CI 0.53 to 1.85; 258 participants, low quality evidence). We found no data for the outcomes of acute toxicity, new ipsilateral breast primaries, costs, quality of life or consumer preference.

AUTHORS' CONCLUSIONS

The limitations of the data currently available mean that we cannot make definitive conclusions about the efficacy and safety or ways to deliver of PBI/APBI. We await completion of ongoing trials.

Intraoperative radiotherapy for breast cancer

Intra-operative radiotherapy (IORT) as a treatment for breast cancer is a relatively new technique that is designed to be a replacement for whole breast external beam radiotherapy (EBRT) in selected women suitable for breast-conserving therapy. This article reviews twelve reasons for the use of the technique, with a particular emphasis on targeted intra-operative radiotherapy (TARGIT) which uses X-rays generated from a portable device within the operating theatre immediately after the breast tumour (and surrounding margin of healthy tissue) has been removed. The delivery of a single fraction of radiotherapy directly to the tumour bed at the time of surgery, with the capability of adding EBRT at a later date if required (risk-adaptive technique) is discussed in light of recent results from a large multinational randomised controlled trial comparing TARGIT with EBRT. The technique avoids irradiation of normal tissues such as skin, heart, lungs, ribs and spine, and has been shown to improve cosmetic outcome when compared with EBRT. Beneficial aspects to both institutional and societal economics are discussed, together with evidence demonstrating excellent patient satisfaction and quality of life. There is a discussion of the published evidence regarding the use of IORT twice in the same breast (for new primary cancers) and in patients who would never be considered for EBRT because of their special circumstances (such as the frail, the elderly, or those with collagen vascular disease). Finally, there is a discussion of the role of the TARGIT Academy in developing and sustaining high standards in the use of the technique.

Shortened radiation therapy schedules for early-stage breast cancer: a review of hypofractionated whole-breast irradiation and accelerated partial breast irradiation

Breast-conserving therapy consisting of segmental mastectomy followed by whole-breast irradiation (WBI) has become widely accepted as an alternative to mastectomy as a treatment for women with early-stage breast cancer. WBI is typically delivered over the course of 5-6 weeks to the whole breast. Hypofractionated whole-breast irradiation and accelerated partial breast irradiation have developed as alternative radiation techniques for select patients with favorable early-stage breast cancer. These radiation regimens allow for greater patient convenience and the potential for decreased health care costs. We review here the scientific rationale behind delivering a shorter course of radiation therapy using these distinct treatment regimens in this setting as well as an overview of the published data and pending trials comparing these alternative treatment regimens to WBI.

DEGRO practical guidelines: radiotherapy of breast cancer I: radiotherapy following breast conserving therapy for invasive breast cancer

Background and purpose

The aim of the present paper is to update the practical guidelines for postoperative adjuvant radiotherapy of breast cancer published in 2007 by the breast cancer expert panel of the German Society for Radiooncology (Deutsche Gesellschaft für Radioonkologie, DEGRO). The present recommendations are based on a revision of the German interdisciplinary S-3 guidelines published in July 2012.

Methods

A comprehensive survey of the literature concerning radiotherapy following breast conserving therapy (BCT) was performed using the search terms “breast cancer”, “radiotherapy”, and “breast conserving therapy”. Data from lately published meta-analyses, recent randomized trials, and guidelines of international breast cancer societies, yielding new aspects compared to 2007, provided the basis for defining recommendations according to the criteria of evidence-based medicine. In addition to the more general statements of the DKG (Deutsche Krebsgesellschaft), this paper addresses indications, target definition, dosage, and technique of radiotherapy of the breast after conservative surgery for invasive breast cancer.

Results

Among numerous reports on the effect of radiotherapy during BCT published since the last recommendations, the recent EBCTCG report builds the largest meta-analysis so far available. In a 15 year follow-up on 10,801 patients, whole breast irradiation (WBI) halves the average annual rate of disease recurrence (RR 0.52, 0.48–0.56) and reduces the annual breast cancer death rate by about one sixth (RR 0.82, 0.75–0.90), with a similar proportional, but different absolute benefit in prognostic subgroups (EBCTCG 2011).

Furthermore, there is growing evidence that risk-adapted dose augmentation strategies to the tumor bed as well as the implementation of high precision RT techniques (e.g., intraoperative radiotherapy) contribute substantially to a further reduction of local relapse rates. A main focus of ongoing research lies in partial breast irradiation strategies as well as WBI hypofractionation schedules. The potential of both in replacing normofractionated WBI has not yet been finally clarified.

Conclusion

After breast conserving surgery, no subgroup even in low risk patients has yet been identified for whom radiotherapy can be safely omitted without compromising local control and, hence, cancer-specific survival. In most patients, this translates into an overall survival benefit.

Accelerated partial breast irradiation for breast cancer: a meta-analysis

To evaluate the long-term effect of breast conservation with accelerated partial breast irradiation (APBI) for early-stage breast cancer, PubMed, EMBASE, Cochrane Library, Web of Science, Chinese Biomedical Literature Database, Chinese Scientific Journals Full-text Database, and China Journal Full-text Database were searched to identify relevant original published trials. Randomized controlled trials in any language comparing APBI with whole-breast radiotherapy in patients with early-stage breast cancer were included. RevMan 5 software was used for statistical analysis. Four trials involving 919 patients were included. The rate of 5- and 7-year excellent/good cosmetic results was significant {odds ratio (OR) = 2.09 [95% confidence interval (CI) = 1.21-3.62]} between two groups. The 5- and 8-year overall survival had no significant difference [OR = 1.76 (95% CI = 0.67-4.62) and OR = 0.86 (95% CI = 0.44-1.66)]. The 10-year overall survival had significant differences [OR = 0.56 (95% CI = 0.35-0.91)]. There were no differences in the 5-year local recurrence (LR)-free survival [OR = 0.65 (95% CI = 0.18-2.34)], cancer-specific survival [OR = 1.67 (95% CI = 0.39-7.12)], disease-free survival [OR = 0.84 (95% CI = 0.38-1.84)], LR [OR = 1.36 (95% CI = 0.46-3.99)], the rate of contralateral breast cancer [OR = 2.82 (95% CI = 0.73-10.89)], and distant metastasis [OR = 0.71 (95% CI = 0.22-2.31)]. APBI significantly improved the rate of excellent/good cosmetic results anywhere in the breast, shortened the treatment time, alleviated the pain, and improved the quality of life. Future large-scale, high-quality, and double-blind trials are needed.

Intraoperative radiotherapy versus external radiotherapy for early breast cancer (ELIOT): a randomised controlled equivalence trial

BACKGROUND

Intraoperative radiotherapy with electrons allows the substitution of conventional postoperative whole breast irradiation with one session of radiotherapy with the same equivalent dose during surgery. However, its ability to control for recurrence of local disease required confirmation in a randomised controlled trial.

METHODS

This study was done at the European Institute of Oncology (Milan, Italy). Women aged 48-75 years with early breast cancer, a maximum tumour diameter of up to 2·5 cm, and suitable for breast-conserving surgery were randomly assigned in a 1:1 ratio (using a random permuted block design, stratified for clinical tumour size [<1·0 cm vs 1·0-1·4 cm vs ≥1·5 cm]) to receive either whole-breast external radiotherapy or intraoperative radiotherapy with electrons. Study coordinators, clinicians, and patients were aware of the assignment. Patients in the intraoperative radiotherapy group received one dose of 21 Gy to the tumour bed during surgery. Those in the external radiotherapy group received 50 Gy in 25 fractions of 2 Gy, followed by a boost of 10 Gy in five fractions. This was an equivalence trial; the prespecified equivalence margin was local recurrence of 7·5% in the intraoperative radiotherapy group. The primary endpoint was occurrence of ipsilateral breast tumour recurrences (IBTR); overall survival was a secondary outcome. The main analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01849133.

FINDINGS

1305 patients were randomised (654 to external radiotherapy and 651 to intraoperative radiotherapy) between Nov 20, 2000, and Dec 27, 2007. After a medium follow-up of 5·8 years (IQR 4·1-7·7), 35 patients in the intraoperative radiotherapy group and four patients in the external radiotherapy group had had an IBTR (p<0·0001). The 5-year event rate for IBRT was 4·4% (95% CI 2·7-6·1) in the intraoperative radiotherapy group and 0·4% (0·0-1·0) in the external radiotherapy group (hazard ratio 9·3 [95% CI 3·3-26·3]). During the same period, 34 women allocated to intraoperative radiotherapy and 31 to external radiotherapy died (p=0·59). 5-year overall survival was 96·8% (95% CI 95·3-98·3) in the intraoperative radiotherapy group and 96·9% (95·5-98·3) in the external radiotherapy group. In patients with data available (n=464 for intraoperative radiotherapy; n=412 for external radiotherapy) we noted significantly fewer skin side-effects in women in the intraoperative radiotherapy group than in those in the external radiotherapy group (p=0·0002).

INTERPRETATION

Although the rate of IBTR in the intraoperative radiotherapy group was within the prespecified equivalence margin, the rate was significantly greater than with external radiotherapy, and overall survival did not differ between groups. Improved selection of patients could reduce the rate of IBTR with intraoperative radiotherapy with electrons.

FUNDING

Italian Association for Cancer Research, Jacqueline Seroussi Memorial Foundation for Cancer Research, and Umberto Veronesi Foundation.

Breast-conserving therapy with partial or whole breast irradiation: ten-year results of the Budapest randomized trial

BACKGROUND AND PURPOSE

To report the long-term results of a single-institution randomized study comparing the results of breast-conserving treatment with partial breast irradiation (PBI) or conventional whole breast irradiation (WBI).

PATIENTS AND METHODS

Between 1998 and 2004, 258 selected women with pT1 pN0-1mi M0, grade 1-2, non-lobular breast cancer without the presence of extensive intraductal component and resected with negative margins were randomized after BCS to receive 50 Gy WBI (n=130) or PBI (n=128). The latter consisted of either 7 × 5.2 Gy high-dose-rate (HDR) multi-catheter brachytherapy (BT; n=88) or 50 Gy electron beam (EB) irradiation (n=40). Primary endpoint was local recurrence (LR) as a first event. Secondary endpoints were overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), and cosmetic results.

RESULTS

After a median follow up of 10.2 years, the ten-year actuarial rate of LR was 5.9% and 5.1% in PBI and WBI arms, respectively (p=0.77). There was no significant difference in the ten-year probability of OS (80% vs 82%), CSS (94% vs 92%), and DFS (85% vs 84%), either. The rate of excellent-good cosmetic result was 81% in the PBI, and 63% in the control group (p<0.01).

CONCLUSIONS

Partial breast irradiation delivered by interstitial HDR BT or EB for a selected group of early-stage breast cancer patients produces similar ten-year results to those achieved with conventional WBI. Significantly better cosmetic outcome can be achieved with HDR BT implants compared with the outcome after WBI.