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

[Towards an integrated approach to cardiovascular toxicities related to the treatments of breast cancer]

There is an increasing number of therapeutic options in breast cancer management. While prognosis improves, the cardiac toxicity related to treatments remains a significant issue. This toxicity has several clinical presentations and can be explained by complex and diverse molecular mechanisms. Systemic treatments (anthracyclines, inhibitors of HER2 signaling pathway, hormone therapy, antiangiogenic agents) and radiotherapy have their own cardiac toxicity. However, the toxicities associated with these treatments may potentiate together and the existence of pre-existing cardiovascular risk factors should be taken into account. The assessment of cardiac hazard evolves toward a multifactorial approach. Several possibilities exist to minimize the incidence of cardiac complications. Those include pharmacological and technological innovations, but also a more accurate selection of patients and a growing involvement of practitioners in the field of cardiac toxicity, which is prerequisite for an early management of cardiac events.

Intraoperative radiation therapy: a critical analysis of the ELIOT and TARGIT trials. Part 1--ELIOT

INTRODUCTION

Two randomized intraoperative radiation therapy trials for early-stage breast cancer were recently published. The ELIOT Trial used electrons (IOERT), and the TARGIT-A Trial Update used 50-kV X-rays (IORT). These studies were compared for similarities and differences. The results were analyzed and used to determine which patients might be suitable for single-dose treatment.

METHOD

The primary sources of data were the ELIOT Trial and TARGIT-A Trial, as well as a comprehensive analysis of the peer-reviewed literature of accelerated partial breast irradiation (APBI) using 50-kV X-rays or electrons. Studies published or presented prior to March 2014 were analyzed for efficacy, patient restrictions, complications, and outcome.

RESULTS

With a median follow-up of 5.8 years, the 5-year recurrence rates for ELIOT versus external beam radiation therapy (EBRT) patients were 4.4 % and 0.4 %, respectively, p = .0001. A low-risk ELIOT group was identified with a 5-year recurrence rate of 1.5 %. With a median follow-up of 29 months, the 5-year recurrence rates for the TARGIT-A versus EBRT patients were 3.3 % and 1.3 %, respectively, p = .042.

CONCLUSION

With 5.8 years of median follow-up, IOERT appears to have a subset of low-risk women for whom IOERT is acceptable. With 29 months of median follow-up the results of IORT with 50-kV devices are promising, but longer follow-up data are required. At the current time, single-fraction IOERT or IORT patients should be treated under strict institutional protocols.

A cohort analysis to identify eligible patients for intraoperative radiotherapy (IORT) of early breast cancer

BACKGROUND

Since the results from the randomized TARGIT A trial were published, intraoperative radiotherapy (IORT) is used more often. IORT can be provided as accelerated partial breast irradiation (APBI) or as a boost. The definition of suitable patients for IORT as APBI differs between different national societies (e.g. ESTRO and ASTRO) and different inclusion criteria of trials and so does the eligibility of patients. This analysis identifies eligible patients for IORT according to available consensus statements and inclusion criteria of the ongoing TARGIT trials.

METHODS

Between 01/03 - 12/09, 1505 breast cancer cases were treated at the breast cancer center at the University Medical Center Mannheim. Complete data sets for age, stage (T, N, and M), histology and hormone receptor status were available in 1108 cases. Parameters to identify eligible patients are as follows: ESTRO: >50 years, invasive ductal carcinoma/other favorable histology (IDC), T1-2 (≤3 cm), N0, any hormone receptor status, M0; ASTRO: ≥60 years, IDC, T1, N0, positive estrogen hormone receptor status, M0; TARGIT E "elderly", risk adapted radiotherapy with IORT followed by external beam radiotherapy in case of risk factors in final histopathology, phase II: ≥70 years, IDC, T1, N0, any hormone receptor status, M0; TARGIT C "consolidation", risk adapted radiotherapy, phase IV: ≥50 years, IDC, T1, N0, positive hormone receptor status, M0; TARGIT BQR "boost quality registry": every age, every histology, T1-2 (max. 3.5 cm), any hormone receptor status, N0/+, M0/+.

RESULTS

Out of the 1108 cases, 379 cases (34.2%) were suitable for IORT as APBI regarding the ESTRO and 175 (15.8%) regarding the ASTRO consensus statements. 82 (7.4%) patients were eligible for the TARGIT E trial, 258 (23.3%) for the TARGIT C trial and 671 (60.6%) for the TARGIT BQR registry. According to the consensus statements of ASTRO (45.1%) and ESTRO (41.4%) about half of the eligible patients were treated with IORT as APBI. From the eligible patients fulfilling the criteria for IORT boost (35%) about one third was eventually treated.

CONCLUSIONS

Patient selection for IORT should be restrictive. For IORT as APBI the TARGIT trials are even more restrictive including patients than the ESTRO and ASTRO consensus statements.

[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.

Accelerated partial breast irradiation in the elderly: 5-year results of high-dose rate multi-catheter brachytherapy

Objective

To evaluate clinical outcome after accelerated partial breast irradiation (APBI) in the elderly after high-dose-rate interstitial multi-catheter brachytherapy (HIBT).

Methods and materials

Between 2005 and 2013, 70 patients underwent APBI using HIBT. Catheter implant was performed intra or post-operatively (referred patients) after lumpectomy and axillary sentinel lymph node dissection. Once the pathological results confirmed the indication of APBI, planification CT-scan was performed to deliver 34 Gy/10f/5d or 32 Gy/8f/4d. Dose-volume adaptation was manually achieved (graphical optimization). Dosimetric results and clinical outcome were retrospectively analyzed. Physician cosmetic evaluation was reported.

Results

With a median follow-up of 60.9 months [4.6 – 90.1], median age was 80.7 years [62 – 93.1]. Regarding APBI ASTRO criteria, 61.4%, 18.6% and 20% were classified as suitable, cautionary and non-suitable respectively. Axillary sentinel lymph node dissection was performed in 94.3%; 8 pts (11.5%) presented an axillary involvement. A median dose of 34 Gy [32 – 35] in 8 to 10 fractions was delivered. Median CTV was 75.2 cc [16.9 – 210], median D90 EQD2 was 43.3 Gy [35 – 72.6] and median DHI was 0.54 [0.19 – 0.74]. One patient experienced ipsilateral recurrence (5-year local free recurrence rate: 97.6%. Five-year specific and overall survival rates were 97.9% and 93.2% respectively. Thirty-four patients (48%) presented 47 late complications classified grade 1 (80.8%) and grade 2 (19.2%) with no grade ≥ 3. Cosmetic results were considered excellent/good for 67 pts (95.7%).

Conclusion

APBI using HIBT and respecting strict rules of implantation and planification, represents a smart alternative between no post-operative irradiation and whole breast irradiation delivered over 6 consecutive weeks.

Cardiac dose sparing and avoidance techniques in breast cancer radiotherapy

Breast cancer radiotherapy represents an essential component in the overall management of both early stage and locally advanced breast cancer. As the number of breast cancer survivors has increased, chronic sequelae of breast cancer radiotherapy become more important. While recently published data suggest a potential for an increase in cardiac events with radiotherapy, these studies do not consider the impact of newer radiotherapy techniques commonly utilized. Therefore, the purpose of this review is to evaluate cardiac dose sparing techniques in breast cancer radiotherapy. Current options for cardiac protection/avoidance include (1) maneuvers that displace the heart from the field such as coordinating the breathing cycle or through prone patient positioning, (2) technological advances such as intensity modulated radiation therapy (IMRT) or proton beam therapy (PBT), and (3) techniques that treat a smaller volume around the lumpectomy cavity such as accelerated partial breast irradiation (APBI), or intraoperative radiotherapy (IORT). While these techniques have shown promise dosimetrically, limited data on late cardiac events exist due to the difficulties of long-term follow up. Future studies are required to validate the efficacy of cardiac dose sparing techniques and may use surrogates for cardiac events such as biomarkers or perfusion imaging.

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.

Progress and controversies: radiation therapy for invasive breast cancer

Radiation therapy is a critical component of the multidisciplinary management of invasive breast cancer. In appropriately selected patients, radiation not only improves local control, sparing patients the morbidity and distress of local recurrence, but it also improves survival by preventing seeding and reseeding of distant metastases from persistent reservoirs of locoregional disease. In recent years, considerable progress has been made toward improving our ability to select patients most likely to benefit from radiotherapy and to administer treatment in ways that maximize clinical benefit while minimizing toxicity and burden. This article reviews the role of radiation therapy in invasive breast cancer management, both after breast-conserving surgery and after mastectomy. It focuses particularly on emerging evidence that helps to define the clinical situations in which radiotherapy is indicated, the appropriate targets of treatment, and optimal approaches for minimizing both the toxicity and the burden of treatment, all in the context of the evolving surgical and systemic management of this common disease. It includes a discussion of new approaches in breast cancer radiotherapy, including hypofractionation and intensity modulation, as well as a discussion of promising avenues for future research.

Multi-catheter interstitial accelerated partial breast irradiation - tips and tricks for a good insertion

Adjuvant radiotherapy is recommended post breast conserving surgery. Accelerated Partial Breast Irradiation (APBI) offers a more attractive shorter course of treatment over 5 days compared to standard conventional external beam radiotherapy, which is often protracted. Multi-catheter interstitial APBI offers excellent dosimetric coverage. This article describes two insertion techniques for multi-catheter interstitial APBI, the operator dependent freehand technique, and the easier to learn template technique. The indications, benefits, and drawbacks of these two techniques are discussed.

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.

Evaluating radiotherapy options in breast cancer: does intraoperative radiotherapy represent the most cost-efficacious option?

INTRODUCTION

This study analyzed the cost-efficacy of intraoperative radiation therapy (IORT) compared with whole-breast irradiation (WBI) and accelerated partial-breast irradiation (APBI) for early-stage breast cancer.

MATERIALS AND METHODS

Data for this analysis came from 2 phase III trials: the TARGIT (Targeted Intraoperative Radiotherapy) trial and the ELIOT (Electron Intraoperative Radiotherapy) trial. Cost analyses included a cost-minimization analysis and an incremental cost-effectiveness ratio analysis including a quality-adjusted life-year (QALY) analysis. Cost analyses were performed comparing IORT with WBI delivered using 3-dimensional conformal radiotherapy (3D-CRT), APBI 3D-CRT, APBI delivered with intensity-modulated radiotherapy (IMRT), APBI single-lumen (SL), APBI multilumen (ML), and APBI interstitial (I).

RESULTS

Per 1000 patients treated, the cost savings with IORT were $3.6-$4.3 million, $1.6-$2.4 million, $3.6-$4.4 million, $7.5-$8.2 million, and $2.8-$3.6 million compared with WBI 3D-CRT, APBI IMRT, APBI SL, APBI ML, and APBI I, respectively, with a cost decrement of $1.6-$2.4 million compared with APBI 3D-CRT based on data from the TARGIT trial. The costs per QALY for WBI 3D-CRT, APBI IMRT, APBI SL, APBI ML, and APBI I compared with IORT were $47,990-$60,002; $17,335-$29,347; $49,019-$61,031; $108,162-$120,173; and $36,129-$48,141, respectively, based on data from the ELIOT trial. These results are consistent with APBI and WBI being cost-effective compared with IORT.

CONCLUSION

Based on cost-minimization analyses, IORT represents a potential cost savings in the management of early-stage breast cancer. However, absolute reimbursement is misleading, because when additional medical and nonmedical costs associated with IORT are factored in, WBI and APBI represent cost-effective modalities based on cost-per-QALY analyses. They remain the standard of care.

Outcome of a phase II prospective study on partial breast irradiation with interstitial multi-catheter high-dose-rate brachytherapy

BACKGROUND AND PURPOSE

Partial breast irradiation (PBI) is an alternative to whole-breast irradiation after breast-conserving surgery in selected patients. Until the results of randomized phase III studies are available, phase II studies inform about PBI. We report the 5 year results of a phase II prospective study with PBI using interstitial multi-catheter high-dose-rate brachytherapy (ClinicalTrials.gov Identifier: NCT00499057).

METHODS

Hundred patients received PBI (4 Gy, twice a day for 4 days, until 32 Gy). Inclusion criteria were: age ≥ 40years, infiltrating carcinoma without lobular histology, ductal in situ carcinoma, tumor size ≤ 2.5 cm, negative surgical margins and axillary lymph nodes.

RESULTS

At a median follow-up of 60 months late toxicity occurred in 25 patients; the 5-year probability of freedom from late toxicity was 72.6% (95% CI: 63.7-81.7). Tamoxifen was the only significant risk factor for late toxicity. Cosmetic results, judged by physicians and patients, were good/excellent in 98 patients. Three local relapses (1 true, 2 elsewhere) and 1 regional relapse occurred. The 5-year probability of local or regional relapse-free survival was 97.7% (95% CI: 91.1-99.4) and 99.0% (95% CI: 92.9-99.8), respectively.

CONCLUSION

PBI with interstitial multi-catheter brachytherapy is associated with low relapse and late toxicity rates.