External beam boost versus interstitial high-dose-rate brachytherapy boost in the adjuvant radiotherapy following breast-conserving therapy in early-stage breast cancer: a dosimetric comparison

Traditional Clinicopathological Biomarkers Still Determine Disease-Free and Overall Survival in Invasive Breast Cancer Patients: A Pilot Study

Background: Molecular classification, tumor diameter, Ki67 expression, and brachytherapy administration still act as the most potent potential predictors of breast cancer recurrence and overall survival. Methods: Over the period of 23 months, we included in the study 92 invasive breast cancer (IBrC) patients initially diagnosed at the Clinical Ward of Breast Cancer and Reconstructive Surgery, Oncology Center in Bydgoszcz, Poland. The probability of disease-free survival (DFS) and overall survival (OS) in relation to potential prognostic factors for the patients were determined using a Kaplan-Meier analysis, and univariate and multivariate Cox regression analyses evaluated the predictive factors of IBrC patients. The investigation of the potential prognostic model's accuracy was analyzed using the ROC curve. Results: Patients with tumor size < 2 cm, Ki67 expression < 20%, luminal-A molecular subtype, and extra-dose brachytherapy boost administration displayed the most favorable prognosis according to breast cancer disease-free survival and overall survival. The estimated 5 year probability of DFS and OS rates in women with tumor diameter < 2 cm were 89% and 90%, respectively. In tumor diameter > 2 cm, the estimated 5 year probability of DFS was 73% and OS was 76%. Interestingly, the tumor diameter of 1.6 cm with a specificity of 60.5% and a sensitivity of 75% occurred as the best threshold point to differentiate patients with cancer recurrence from those without cancer progression. Conclusions: Our study provides essential information on the clinicopathological profile and future outcomes of early stage IBrC patients. Furthermore, the tumor diameter cut-off value of 1.6 cm discriminating between disease recurrence and those without disease progression patients represents an innovative direction for further research.

Recent progress in radioactive seed implantation brachytherapy of non-small cell lung cancer: a narrative review

Background and Objective

Brachytherapy, a new form of radiation therapy, has been used to treat lung cancer and consists of two main forms of treatment: endobronchial brachytherapy and radioactive seed implantation brachytherapy (RSI-BT), the latter of which is used to treat non-small cell lung cancer (NSCLC). The use of RSI-BT in the treatment of NSCLC at our centre has yielded some positive results.

Methods

To more fully consider the context of this application, we conducted a search of PubMed from 2018 to March 5, 2023. The search included a combination of the MeSH terms: "brachytherapy" and "lung neoplasm".

Key Content and Findings

The majority of NSCLC patients who received RSI-BT achieved positive benefits. Most patients had a progression-free survival (PFS) of between 12 and 18 months. Additionally, radioactive particle stent implantation as a specific RSI-BT has shown therapeutic potential in the treatment of malignant airway obstruction. With the application of new technologies, RSI-BT will become more precise, efficient and inexpensive.

Conclusions

This review demonstrates that RSI-BT can be therapeutic in the treatment of both early and advanced NSCLC with manageable complications. There have also been reports on the combination of RSI-BT with other therapies, but more research is needed on the combination of RSI-BT with them.

Analysis of multicatheter interstitial brachytherapy: Accelerated partial breast irradiation in a retrospective cohort of early-stage breast cancer patients

PURPOSE

To determine cardiac dose received by patients treated with high dose rate interstitial brachytherapy. Patients with early-stage, node negative breast cancer can be treated using multi-catheter interstitial brachytherapy accelerated partial breast irradiation (MIB-APBI), with the benefit of reduced treatment volumes and favorable toxicity.

METHODS AND MATERIALS

We conducted a retrospective review of left-sided breast cancer patients treated using MIB-APBI at our institution since 2014. The mean heart dose (MHD) was calculated using the Oncentra 3.2 planning system. The minimum distance between the planning target volume (PTVeval) and heart contour was measured manually.

FINDINGS

81 patients were included. The upper outer quadrant was the most common site. The MHD was 97.8 cGy (EQD2a/b=2) (range 22-229 cGy). MHD significantly correlated with the closest distance between PTVeval and heart contour (correlation coefficient -0.823, p <0.001); size of PTVeval (cc) and quadrant location did not.

CONCLUSIONS

Appropriately selected women with early-stage, low-risk, left-sided breast cancer who received MIB-APBI had acceptable MHD. There was a strong correlation between the distance of PTVeval and MHD. Quadrant breast tumor is in cannot be used as a surrogate for MHD in brachytherapy. Our findings contribute to the growing evidence of the utility and safety of MIB-APBI.

Intraoperative Radiotherapy as a Tumour-Bed Boost Combined with Whole Breast Irradiation Versus Conventional Radiotherapy in Patients with Early-Stage Breast Cancer: A Systematic Review and Meta-analysis

BACKGROUND

There is no definitive answer regarding the efficacy of intraoperative radiotherapy (IORT) as a tumour bed boost for patients with early-stage breast cancer. The purpose of this meta-analysis was to summarise the available evidence and explore the efficacy and safety of IORT combined with whole breast irradiation (WBI) versus conventional radiotherapy in women with early-stage breast cancer who underwent breast-conserving surgery.

METHODS

The PUBMED, MEDLINE, EMBASE, Web of Science, and Cochrane Library databases were searched from inception to December 31, 2022. We collected studies on the efficacy, cosmetic outcome, and safety of IORT boost combined with WBI compared with those of conventional radiotherapy in patients with early-stage breast cancer after breast-conserving surgery. Two authors independently performed the literature selection and data extraction. The quality of the randomised, controlled trials (RCTs) was assessed according to the PEDro scale. The quality of non-RCTs was assessed according to the Methodological Index for Non-Randomised Studies. Risk ratios (RRs) for the local recurrence rate (LRR), distant metastasis rate (DMR), disease-free survival (DFS), cosmetic outcome, and toxicity were pooled using fixed or random effects models. Meta-analysis of the included studies was performed by using RevMan 5.3 software.

RESULTS

Nine studies, including one RCT and eight non-RCTs, with a total of 3219 patients were included. In terms of LRR, there was no significant benefit of IORT boost+WBI over conventional radiotherapy (with or without the tumour bed boost) (RR = 0.77, 95% confidence interval (CI): 0.54-1.09, P = 0.14), but a trend towards benefit could be identified. There was a significant reduction in DMR in the IORT boost+WBI group (RR = 0.63, 95% CI: 0.46-0.85, P = 0.003) and a significant improvement in DFS (RR = 0.40, 95% CI: 0.25-0.65, P = 0.0002). Exploratory subgroup analysis showed that the DMR and DFS of the electron boost group were significantly better than those of conventional radiotherapy group, and there was a tendency for LRR to improve in the electron boost group. However, the LRR, DMR, and DFS did not effectively improve in the x-ray boost group. In terms of appearance and toxicity, there were no significant differences in cosmetic outcome, fibrosis, and hyperpigmentation between the two groups (RR = 0.99, 95% CI: 0.91-1.07, P = 0.78; RR = 1.02, 95% CI: 0.41-2.56, P = 0.96; RR = 0.42, 95% CI: 0.10-1.72, P = 0.23), but the incidence of oedema was significantly reduced in the IORT boost+WBI group (RR = 0.27, 95% CI: 0.13-0.59, P = 0.0009).

CONCLUSIONS

IORT boost+WBI is more effective than conventional radiotherapy after breast-conserving surgery in patients with early-stage breast cancer, and electron boost exhibits better efficacy than x-ray boost. In addition, the cosmetic and safety profiles of IORT boost+WBI are not inferior to those of conventional radiotherapy.

Different approaches to target volume definition and boost delivery in surgery de-escalation clinical trial in breast cancer patients with pathological complete response

PURPOSE

We evaluate various approaches to target volume definition and boost delivery in patients with complete response to neoadjuvant systemic therapy (NST) who were treated by radiotherapy without a surgery.

MATERIALS AND METHODS

A pathological complete response (pCR) was diagnosed in 21 of 27 patients included in "surgery de-escalation" prospective observation study. Clips were placed in the primary tumor volume (PrTV) before NST and during the vacuum aspiration biopsy. Twenty patients with pCR underwent the whole breast irradiation and a boost to the PrTV. High-dose rate brachytherapy (HDRB) was the basic technique for boost delivery. Finally, we identified the value of fused images (computed tomography [CT] before NST with simulation CT), clips and their combination for an accurate boost delivery.

RESULTS

A complete overlap between PrTV on pre-treatment CT with the localization of the clips on simulation CT was mentioned in 10, partial mismatch in three patients. In 12 of these 13 women, HDRB was successfully used for the boost delivery. In five cases we mentioned a marked discrepancy between the PrTV on fused images and the topography of the clips. In other two women we did not find clips on simulation CT. The fused images in five of these seven patients showed anatomical landmarks (scar, fibrosis) used for identification of the gross tumor volume. In all 20 women with pCR (average follow-up of 16.6 months), there were no locoregional recurrences.

CONCLUSION

Combination of the clips with fusion of pre-NST and simulation CTs is important for an accurate boost delivery.

Risk Factors for Operation Complications of High Dose Rate 3-Dimensional Interstitial Brachytherapy for Lung Cancer

BACKGROUND

The risk factors for operation complications of high-dose-rate dimensional (3D) interstitial brachytherapy for lung malignant tumors are still unclear. We aimed to provide a reliable reference for the preoperative safety assessment of interstitial brachytherapy.

PATIENTS AND METHODS

We analyzed the degree and incidence of operational complications in 120 eligible patients with lung carcinoma who underwent computed tomography (CT)-guided HDR interstitial brachytherapy. Univariate and multivariate analyses were used to study the relationships between patient-related factors, tumor-related factors, operation-related factors, and operational complications.

RESULTS

The most frequent complications of CT-guided HDR interstitial brachytherapy were pneumothorax and hemorrhage. In univariate analysis, smoking, emphysema, distance of implanted needles through the normal lung tissue, number of implanted needle adjustments, and distance of the lesion from the pleura were the risk factors for pneumothorax; the tumor size, distance of the tumor from the pleura, number of implanted needle adjustments, and distance of the implanted needle through the normal lung tissue were risk factors for hemorrhage. In multivariate analysis, the depth of the implanted needle through the normal lung tissue and distance of the lesion from the pleura were independent risk factors for pneumothorax. Tumor size, number of implanted needle adjustments, and distance through normal lung tissue were independent risk factors for hemorrhage.

CONCLUSION

This study provides a reference for the clinical treatment of lung cancer by analyzing the risk factors for complications of interstitial brachytherapy.

Overall Survival and Related Factors of Patients Undergoing Breast-Conserving Surgery with Boost Through Interstitial Brachytherapy in a Cancer Center in Medellin, Colombia

Liza María González-HernándezPatients with breast cancer undergoing conservative surgery require management with radiotherapy to decrease the risk of recurrence. Moreover, the use of tumor bed boost in high-risk patients has shown an absolute reduction in the 10-year local recurrence risk from 23.9 to 13.5%. Therefore, this study aimed to estimate the overall survival of a group of patients undergoing conservative surgery with a boost through interstitial brachytherapy at a cancer center in Medellin, Colombia. A retrospective cohort study was performed, and records from 2014 to 2020 of patients with in situ or infiltrating breast cancer treated with a boost through interstitial brachytherapy were included. Univariate analysis was conducted to characterize the study population; median survival was calculated using the Kaplan-Meier method. Moreover, associations concerning survival were calculated with each of the factors independently. A total of 186 patients were included. Their overall survival was 93.5%, with a median survival of 79 months. The presence of negative hormone receptors, having two or more irradiated fields and having a locally advanced stage were factors associated independently with higher mortality. The overall survival of patients with in situ or infiltrating breast cancer was favorable and correlated with studies regarding intervention with a boost through interstitial brachytherapy and the factors associated with higher mortality, such as having a locally advanced stage.

Predictors of poor cosmesis in breast cancer patients treated with adjuvant whole breast radiation therapy plus high-dose-rate interstitial brachytherapy boost after breast conservation surgery

Purpose

To identify patient, tumor, and treatment-related factors, which predict cosmesis in breast cancer survivors treated with adjuvant whole breast irradiation (WBI) plus high-dose-rate (HDR) multicatheter interstitial brachytherapy (MIBT) boost after breast conservation surgery.

Material and methods

At least 12 months after completion of radiotherapy, cosmetic outcomes were measured both objectively with BCCT.core software (using a front view digital photograph), and subjectively according to Harvard's criteria. MIBT dose fractionation regimen was 13.6 Gy/4 fractions (bid). To evaluate the correlation between cosmetic scores and dose-volume histogram (DVH) parameters, WBI and MIBT plans were retrospectively analyzed, and ipsilateral skin and breast biologically equivalent dosimetric indices were recorded (α/β = 3 Gy). A multivariate ordinal logistic regression model was used for statistical analysis.

Results

Twenty-eight consecutive patients were enrolled into this study. The median time from completion of radiation therapy to cosmesis scoring was 18 months. In evaluation with BCCT.core software, no patient was scored as excellent. Cosmesis was good in 18%, fair in 50%, and poor in 32% of patients. According to Harvard's scale, 10.5% of patients had excellent cosmesis, and 43%, 28.5%, and 18% of patients had good, fair, and poor scores, respectively. In univariate analysis, patients with higher absolute MIBT V29Gy (cc), those treated with irradiation of regional lymphatics (odds ratio ≈ 5), and patients with larger breast volumes had statistically significant lower Harvard's scores. In the multivariate model, none of the mentioned factors remained statistically significant, except for a trend for poorer cosmesis in patients with higher absolute MIBT V29Gy (p-value = 0.066).

Conclusions

Based on the results of this study, MIBT breast V29Gy, regional nodal irradiation, and larger breast volumes are the potential factors, which could predict cosmesis.

Early Outcome, Cosmetic Result and Tolerability of an IOERT-Boost Prior to Adjuvant Whole-Breast Irradiation

Background/Aims: Due to its favorable dose distribution and targeting of the region at highest risk of recurrence due to direct visualization of tumor bed, intraoperative electron radiation therapy (IOERT) is used as part of a breast-conserving treatment approach. The aim of this study was to analyze tumor control and survival, as well as the toxicity profile, and cosmetic outcomes in patients irradiated with an IOERT boost for breast cancer. Materials and Methods: 139 Patients treated at our institution between January 2010 and January 2015 with a single boost dose of 10 Gy to the tumor bed during breast-conserving surgery followed by whole-breast irradiation were retrospectively analyzed. Results: 139 patients were included in this analysis. The median age was 54 years (range 28−83 years). The preferred surgical strategy was segmental resection with sentinel lymphonodectomy (66.5%) or axillary dissection (23.1%). Regarding adjuvant radiotherapy, the vast majority received 5 × 1.8 Gy to 50.4 Gy. At a median follow-up of 33.6 months, recurrence-free and overall survival were 95.5% and 94.9%, respectively. No patient developed an in-field recurrence. Seven patients (5.0%) died during the follow-up period, including two patients due to disease recurrence (non-in-field). High-grade (CTCAE > 2) perioperative adverse events attributable to IOERT included wound healing disorder (N = 1) and hematoma (N = 1). High-grade late adverse events (LENT-SOMA grade III) were reported only in one patient with fat necrosis. Low-grade late adverse events (LENT-SOMA grade I-II) included pain (18.0%), edema (10.5%), fibrosis (21%), telangiectasia (4.5%) and pigmentation change (23.0%). The mean breast retraction assessment score was 1.66 (0−6). Both patients and specialists rated the cosmetic result “excellent/good” in 84.8% and 87.9%, respectively. Conclusion: Our study reports favorable data on the cosmetic outcome as well as the acute and early long-term tolerability for patients treated with an IOERT boost. Our oncologic control rates are comparable to the previous literature. However, prospective investigations on the role of IOERT in comparison to other boost procedures would be desirable.

The value of brachytherapy in the age of advanced external beam radiotherapy: a review of the literature in terms of dosimetry

Brachytherapy (BT) has long been used for successful treatment of various tumour entities, including prostate, breast and gynaecological cancer. However, particularly due to advances in modern external beam techniques such as intensity-modulated radiotherapy (IMRT), volume modulated arc therapy (VMAT) and stereotactic body radiotherapy (SBRT), there are concerns about its future. Based on a comprehensive literature review, this article aims to summarize the role of BT in cancer treatment and highlight its particular dosimetric advantages. The authors conclude that image-guided BT supported by inverse dose planning will successfully compete with high-tech EBRT in the future and continue to serve as a valuable modality for cancer treatment.

Dosimetric comparison between interstitial brachytherapy and volumetric-modulated arc therapy for tumor bed boost in breast cancer

Purpose

To dosimetrically compare high-dose-rate interstitial brachytherapy (HDR-BT) with volumetric-modulated arc therapy (VMAT) for tumor bed boost, following breast conservative treatment.

Material and methods

50 patients with early-stage breast cancer who underwent breast conservation surgery, followed by either HDR-BT (n = 25) of 15 Gy in 6 fractions over a period of 3 days, or VMAT dose of 16 Gy in 8 fractions (n = 25) for tumor bed boost, were retrospectively reviewed. All patients received whole breast irradiation of 46 Gy in 23 fractions. Dosimetric parameters for organs at risk (OARs), including ipsilateral and contralateral lungs, heart, contralateral breast, skin, and ribs, were evaluated with the help of dose-volume histograms (DVH).

Results

Heart sparing was similar in both modalities (left-sided breast irradiation, HDR-BT D_2cc 20.5% vs. VMAT 30.2%, p-value = 0.243; right-sided breast irradiation, D_2cc 6.5% vs. 4.4%, p-value = 0.165). Left-sided cases received higher dose to heart compared to right-sided patients. Interstitial brachytherapy resulted in significantly less dose to contralateral breast (D_2cc 4.3% vs. 9.6%, p-value < 0.0001), ipsilateral lung (D_2cc 27.6% vs. 73.2%, p-value < 0.0001), contralateral lung (D_2cc 4.2% vs. 14.5%, p-value < 0.0001), ribs (D_2cc 24.1% vs. 41.2%, p-value < 0.0001), and skin (D_2cc 77.3% vs. 95%, p-value < 0.0001).

Conclusions

HDR-BT-based tumor bed boost irradiation results in significantly lower doses to most organs at risk with similar heart sparing compared to VMAT.

Biological dose summation of external beam radiotherapy for the whole breast and image-guided high-dose-rate interstitial brachytherapy boost in early-stage breast cancer

Purpose

To develop an alternative method for summing biologically effective doses of external beam radiotherapy (EBRT) with interstitial high-dose-rate (HDR) brachytherapy (BT) boost in breast cancer. The total doses using EBRT boost were compared with BT boost using our method.

Material and methods

Twenty-four EBRT plus interstitial HDR-BT plans were selected, and additional plans using EBRT boost were created. The prescribed dose was 2.67/40.05 Gy to whole breast and 4.75/14.25 Gy BT or 2.67/10.7 Gy EBRT to planning target volume (PTV) boost. EBRT and BT computed tomography (CT) were registered twice, including fitting the target volumes and using the lung, and the most exposed volume of critical organs in BT were identified on EBRT CT images. The minimal dose of these from EBRT was summed with their BT dose, and these EQD2 doses were compared using BT vs. EBRT boost. This method was compared with uniform dose conception (UDC).

Results

D₉₀ of PTV boost was significantly higher with BT than with EBRT boost: 67.1 Gy vs. 56.7 Gy, p = 0.0001. There was no significant difference in the dose of non-target and contralateral breast using BT and EBRT boost. D₁ to skin, lung, and D_0.1 to heart were 58.6 Gy vs. 66.7 Gy (p = 0.0025), 32.6 Gy vs. 50.6 Gy (p = 0.0002), and 52.2 Gy vs. 58.1 Gy (p = 0.0009), respectively, while D_0.1 to ribs was 44.3 Gy vs. 37.7 Gy (p = 0.0062). UDC overestimated D₁ (lung) by 54% (p = 0.0001) and D₁ (ribs) by 28% (p = 0.0003).

Conclusions

Based on our biological dose summation method, the total dose of PTV in the breast is higher using BT boost than with EBRT. BT boost yields lower skin, lung, and heart doses, but higher dose to ribs. UDC overestimates lung and ribs doses.

Dosimetric analysis of breast cancer tumor bed boost: An interstitial brachytherapy vs. external beam radiation therapy comparison for deeply seated tumors

PURPOSE

To dosimetrically compare interstitial brachytherapy (MIBT) vs. EBRT (3DCRT and high-energy electron beams) for deep-seated tumor bed boosts (depth ≥4 cm) in early-stage breast cancer.

METHODS AND MATERIALS

Planning CTs of fifteen left-side breast cancer patients previously treated with MIBT boost chosen for this study. MIBT, 3DCRT (three-field technique), and enface high-energy electron (15-18 MeV) plans retrospectively generated on these images. To minimize intrapatient target contour inconsistency, due to a technical limitation for transferring identical contours from brachytherapy to EBRT planning system, spherical volumes delineated as hypothetical CTVs (CTV-H) (depth ≥4 cm with considering the geometry of the brachytherapy implant) instead of original lumpectomy cavities (which had irregular contours). In EBRT, PTV-H=CTV-H+5 mm. To account for beam penumbra, additional PTV-H to beam-edge margins added (3DCRT = 5 mm; electron = 10 mm). Included organs at risk (OARs) were ipsilateral breast, skin, ribs, lung, and heart. Prescribed dose-fractionations were 12 Gy/3fractions (MIBT) and 16 Gy/8fractions (EBRT) (BED = 24 Gy, breast cancer Alpha/Beta = 4 Gy). Biologically equivalent DVH parameters for all techniques compared.

RESULTS

Mean CTV-H depth was 6 cm. Normal breast V_25%-V_100%; skin V_10%-V_90%; rib V_25%-V_75%; lung V_5%-V_25%; heart V_10%; mean lung dose; ribs/lung D_max were lower in MIBT vs. 3CDRT. MIBT reduced breast V_25%-V_125%; skin V_25%-V_125%; rib V_25%-V_75% and V_100%; lung V_25%-V_90%; heart V_10%-V_50%; skin/ribs/lung D_max compared to electrons. In contrast, breast V_125%-V_250% and V_175%-V_250% were increased in MIBT vs. 3DCRT and electron plans, respectively. Electron plans had the minimum mean heart dose.

CONCLUSIONS

From a dosimetric point of view, in deeply-seated lumpectomy beds, MIBT boost better protects OARs from exposure to medium and high doses of radiation compared to 3DCRT and high energy electron beams (except more ipsilateral breast hot spots).

Synchronous bilateral breast cancer patients submitted to conservative treatment and brachytherapy - The experience of a service

Introduction

The incidence of breast carcinoma (BC) has increased in the last years. Between 2 and 12% of patients diagnosed with BC will develop bilateral breast carcinoma (BBC). The treatment of these carcinomas is more aggressive than unilateral BC.

Purpose

To perform a retrospective qualitative analysis of BBC patients whose treatment has included brachytherapy (BT) and to present a revised literature on this issue.

Material and methods

The cases of BBC whose treatment included brachytherapy were revised. The literature on this issue was refreshed.

Results

Five women, aged between 54 and 78 at the time of the diagnosis, submitted to conservative surgery followed by external radiotherapy (RT) with boost of BT or exclusive BT (APBI), in the IPO-P BT Service between 2003 and 2016.

Discussion

The patients with BBC have slightly higher rates of local recurrences, mostly in the tumor bed, where there is a higher risk of local recurrence. Patients treated with BT had lower rates of recurrences than those treated with photons and electrons.

Conclusions

BBC represents a complex challenge for doctors, because in some cases there is a tendency to use more aggressive treatments and, at the same time, it is not easy to achieve the timing for the correct treatment.

A national survey of AIRO (Italian Association of Radiation Oncology) brachytherapy (Interventional Radiotherapy) study group

Purpose

To review brachytherapy resources and to explore current practice patterns in Italy.

Material and methods

In 2016, on behalf of the Italian Association of Radiation Oncology (AIRO), the Brachytherapy Study Group proposed conducting a survey in order to identify brachytherapy practice patterns. An electronic questionnaire was sent to all radiotherapy centres in Italy, asking for: 1. General information on the Radiation Oncology Centre (affiliation, whether brachytherapy was delivered or not); 2. Brachytherapy equipment and human resources; 3. Brachytherapy procedures; 4. Brachytherapy assessment (number of patients treated annually, treated sites, and different modalities of treatments).

Results

A total of 66 questionnaires were returned (33.5% of all brachytherapy centers in Italy), out of which 48 (74%) from non-academic hospitals, 6 (10%) from academic hospitals, and 12 (16%) from private institutions. Most centers (84%) had only one brachytherapy machine; 44% did not deliver brachytherapy treatments or delivered less than demanded because of the lack of staff or expertise, need of modernization, or other reasons. The majority of treatments were administered to outpatients for gynecological tumors.

Conclusions

This survey illustrates the current status of brachytherapy in Italy and should encourage collaboration to develop, implement, and monitor its use when appropriate.

The Role of Brachytherapy in the Treatment of Breast Cancer

Radiotherapy plays an important part in the management of breast cancer. Especially after breast-conserving surgery, external whole breast irradiation, occasionally with an additional local boost, is an integral part of breast conservation. Besides external radiation techniques, brachytherapy (BT) has long been among the treatment options, especially with regard to local boost application. With the emerging implementation of accelerated partial breast irradiation (APBI), BT in general and interstitial multi-catheter BT in particular, are gaining an increasing role in the management of a selected group of early breast cancer patients. APBI is an approach to reduce the irradiated area to the former tumor bed rather than treating the whole breast tissue in patients with a low baseline local recurrence risk. After a variety of phase I-III clinical studies, it is clearly evident that APBI will play a role in the treatment of this selected patient group. In this review, we focus on the clinical development and different available techniques of breast BT and provide a preview of prospects for its use.