Analysis of fat necrosis after adjuvant high-dose-rate interstitial brachytherapy for early stage breast cancer

Thermally boosted interstitial high-dose-rate brachytherapy in high-risk early-stage breast cancer conserving therapy - large cohort long-term results

Background

Early-stage high-risk breast cancer (BC) is standardly treated with breast-conserving therapy (BCT), combined with systemic therapy and radiotherapy (RT) ± tumor bed boost, e.g., with interstitial high-dose-rate brachytherapy (HDR-BT). To improve local recurrence rate (LRR), BT radiosensitization (thermal boost, TB) with interstitial microwave hyperthermia (MWHT) may be an option. The paper aims to report a retrospective single-institutional study on 5- and 10-year local control (LC), distant metastasis-free survival (DMFS), disease-free survival (DFS), overall survival (OS), cosmetic outcome (CO), and late toxicity (fibrosis, fat necrosis) after thermally enhanced HDR-BT boost to the BC tumor bed.

Materials and methods

In 2006-2018, 557 early-stage (I-IIIA) high-risk BC patients were treated with BCT. If indicated, they were administered systemic therapy, then referred for 40.0-50.0 Gy whole breast irradiation (WBI) and 10 Gy interstitial HDR-BT boost (group A). Eligible patients had a single MWHT session preceding BT (group B). Based on present risk factors (RF), medium-risk (1-2 RF) and high-risk subgroups (≥ 3 RF) were formed. Patients were standardly checked, and control mammography (MMG) was performed yearly. Breast cosmesis (Harvard scale) and fibrosis were recorded. LC, DMFS, DFS, and OS were statistically analyzed.

Results

Out of 557 patients aged 57 years (26-84), 364 (63.4%) had interstitial HDR-BT boost (group A), and 193 (34.6%) were preheated with MWHT (group B). Patients in group B had a higher clinical stage and had more RFs. The median follow-up was 65.9. Estimated 5-year and 10-year LC resulted in 98.5% and 97.5%, respectively. There was no difference in LC, DMFS, DFS, and OS between groups A and B and between extracted high-risk subgroups A and B. Five- and ten-year OS probability was 95.4% and 88.0%, respectively, with no difference between groups A and B. Harvard criteria-based CO assessment revealed good/excellent cosmesis in 74.9-79.1%. Tumor bed hardening was present in 40.1-42.2%. Asymptomatic fat necrosis-related macrocalcifications were detected in 15.6%, more frequently in group B (p = 0.016).

Conclusions

Thermally boosted or not, HDR-BT was locally highly effective as part of combined treatment. Five- and ten-year LC, DMFS, DFS, and OS were high and equally distributed between the groups, although TB was prescribed in more advanced one with more RFs. TB did not influence CO and fibrosis. TB added to late toxicity regarding asymptomatic fat necrosis detected on MMG.

Superb Microvascular Imaging at Evaluation of Nonvisible Buried De-epitelized Flap Vascularization in Breast Reconstruction

OBJECTIVE

Superb microvascular imaging is a Doppler technique that increases the visibility of small vessels and gives quantitative information about tissue blood supply by measuring the vascular index. In this study, it is aimed to evaluate the long-term and postradiotherapy changes in blood flow of buried de-epitelized flaps in breast reconstruction by using the quantitative values obtained through superb microvascular imaging.

MATERIALS AND METHODS

Retrospective review of the 14 patients who underwent nipple-sparing breastconserving surgery and immediately breast reconstruction with a de-epitelized extended latissimus dorsi flap was done. In order to demonstrate the effect of radiotherapy on flaps microvascular circulation, patients were evaluated using superb microvascular imaging postoperative first week, first month, and postradiotherapy first week and sixth month. The normal distribution of the data was evaluated with the Shapiro-Wilk test. Paired samples t-test was used for comparisons.

RESULTS

According to the paired samples t-tests, postoperative first week mean vascular index was higher than postoperative first month and postradiotherapy first week (P < .05). Besides, postradiotherapy first week mean vascular index was higher than postoperative first month and also than postradiotherapy sixth month (P < .05).

CONCLUSION

Radiotherapy can affect the results of breast reconstruction by endothelial and fibrotic injury. In this study, the changes in the microvascular circulation of the latissimus dorsi flap were discussed and found to increase at postoperative and postradiotherapy early period related to inflammation and not decreased significantly at long-term follow-up after radiotherapy.

Validation of automated post-adjustments of HDR prostate brachytherapy treatment plans by quantitative measures and oncologist observer study

PURPOSE

The aim was to evaluate a postprocessing optimization algorithm's ability to improve the spatial properties of a clinical treatment plan while preserving the target coverage and the dose to the organs at risk. The goal was to obtain a more homogenous treatment plan, minimizing the need for manual adjustments after inverse treatment planning.

MATERIALS AND METHODS

The study included 25 previously treated prostate cancer patients. The treatment plans were evaluated on dose-volume histogram parameters established clinical and quantitative measures of the high dose volumes. The volumes of the four largest hot spots were compared and complemented with a human observer study with visual grading by eight oncologists. Statistical analysis was done using ordinal logistic regression. Weighted kappa and Fleiss' kappa were used to evaluate intra- and interobserver reliability.

RESULTS

The quantitative analysis showed that there was no change in planning target volume (PTV) coverage and dose to the rectum. There were significant improvements for the adjusted treatment plan in: V150% and V200% for PTV, dose to urethra, conformal index, and dose nonhomogeneity ratio. The three largest hot spots for the adjusted treatment plan were significantly smaller compared to the clinical treatment plan. The observers preferred the adjusted treatment plan in 132 cases and the clinical in 83 cases. The observers preferred the adjusted treatment plan on homogeneity and organs at risk but preferred the clinical plan on PTV coverage.

CONCLUSIONS

Quantitative analysis showed that the postadjustment optimization tool could improve the spatial properties of the treatment plans while maintaining the target coverage.

The treatment of symptomatic fat necrosis: A review and introduction of a new treatment algorithm

OBJECTIVE

Fat necrosis (FN) is a well-known complication in plastic surgery. Excision of symptomatic FN has been the gold standard, but it often results in contour irregularities that require subsequent treatment. Different alternative surgical and nonsurgical management strategies have been described; however, there are currently no guidelines. This literature review aims to provide an overview of available treatment options and current management standards to support clinical decision making.

METHOD

A literature search in the databases PubMed, Embase (via Ovid), and Web Of Science was carried out to identify eligible articles. The search strategy included combinations of the following terms: "Fat necrosis "AND (treatment OR management OR therapy). Six articles discussing or reporting management strategies of FN in a plastic surgery context were included.

RESULTS

A variety of techniques were used to manage symptomatic FN. Asymptomatic or small lesions can be treated conservatively. Oil cyst and moderately sized areas of symptomatic FN can effectively be treated by aspiration, ultrasound-assisted liposuction, or needle aeration. Calcified and large areas of FN require excision and debridement of necrotic fat tissue CONCLUSION: At present, there is no consensus on the management of symptomatic FN. The authors propose a new classification system to aid the guidance of management of symptomatic FN.

Fat necrosis: A consultant's conundrum

Fat necrosis of the breast is a benign non-suppurative inflammation of the adipose tissue and often mimics breast cancers, posing a diagnostic challenge for the clinician and radiologist. It has a myriad of appearances on different imaging techniques, ranging from the pathognomic oil cyst and benign dystrophic calcifications to indeterminate focal asymmetries, architectural distortions, and masses. A combination of different modalities can assist a radiologist in reaching a logical conclusion to avoid unnecessary interventions. The aim of this review article was to provide a comprehensive literature on the various imaging appearances of fat necrosis in the breast. Although a purely benign entity, the imaging appearances on mammography, contrast-enhanced mammography, ultrasound, and magnetic resonance imaging can be quite misleading, especially in post-therapy breasts. The purpose is to provide a comprehensive and all-inclusive review on fat necrosis with a proposed algorithm allowing a systematic approach to diagnosis.

[Diagnosis and management of fat necrosis after autologous fat transplantation of breast]

Objective

To review the diagnosis and management of fat necrosis after autologous fat transplantation of breast.

Methods

Based on the latest related literature, the pathology, clinical and radiographic examinations, influence factors, as well as the management of fat necrosis after autologous fat transplantation for breast augmentation and reconstruction were summarized.

Results

Fat necrosis after breast autologous fat transplantation is histologically manifested as hyaline degeneration, fibrosis, and calcification. The diagnosis of fat necrosis includes clinical examination, imaging examination (ultrasound, mammography, and MRI), and biopsy. The occurrence of fat necrosis is closely related to patient's own reason and fat transplantation technology. Optimizing the process of fat acquisition, purification, and transplantation can reduce the occurrence of fat necrosis. Intervention or not after fat necrosis depends on the nature of the nodules. According to the nature of the the nodules, various methods such as simple aspiration, vibration amplification of sound energy at resonance liposuction, or direct excision can be selected.

Conclusion

Fat necrosis after autologous fat transplantation of breast are difficult to control. How to process fat to minimize the injury and maximize the activity of grafted fat needs further researches.

Reporting of dose-volume specifications for "Martinez Universal Perineal Interstitial Template-based interstitial high-dose-rate brachytherapy for gynecological cancers" according to International Commission on Radiation Units and Measurements 58 with early clinical outcomes

PURPOSE

The study is an audit of reporting dose and volume specifications as per the ICRU 58 for MUPIT-based interstitial brachytherapy in gynecological cancers. Correlation between total reference air kerma (TRAK) and isodose surface was also evaluated to understand the intensity of treatment in interstitial brachytherapy.

METHODS AND MATERIALS

Forty-two patients underwent HDR MUPIT-based interstitial brachytherapy 20 Gy in five fractions after EBRT during 2017-2019. Treated volume, high and low-dose regions, mean central dose, Dose Homogeneity Index (DHI), organ at risk doses, and TRAK values were computed.

RESULTS

High-dose regions V150 mean was 12.4 cc and V200 was 4.58 cc; and low-dose region was 75.92 cc. The mean treated volume was 59.8 cc. The mean central dose was 3.7 Gy. DHI was 79%. The mean D2cm³ bladder and rectum were 2.9 Gy and 2.8 Gy. The mean TRAK was 0.16 cGy per fraction per hour at 1 m. TRAK values showed significant correlation with various isodose volumes (TRAK and V100: r = 0.943 p < 0.0005; and TRAK and V50: r = 0.953; p < 0.0005). A positive correlation was observed between TRAK and the number of needles (r = 0.746; p < 0.0005). At a median followup of 16 months, 4 of 42 patients (9.5%) had local recurrences.

CONCLUSIONS

Our study shows compliance with ICRU 58 recommendations along with certain deviations. Local recurrence rate is acceptable. TRAK shows correlation with surface isodose in MUPIT-based brachytherapy and should to be evaluated in future studies.

Risk Factors for Fat Necrosis After Stereotactic Partial Breast Irradiation for Early-Stage Breast Cancer in a Phase 1 Clinical Trial

PURPOSE

This study reports predictive dosimetric and physiologic factors for fat necrosis after stereotactic-partial breast irradiation (S-PBI).

METHODS AND MATERIALS

Seventy-five patients with ductal carcinoma-in situ or invasive nonlobular epithelial histologies stage 0, I, or II, with tumor size <3 cm were enrolled in a dose-escalation, phase I S-PBI trial between January 2011 and July 2015. Fat necrosis was evaluated clinically at each follow-up. Treatment data were extracted from the Multiplan Treatment Planning System (Cyberknife, Accuray). Univariate and stepwise logistic regression analyses were conducted to identify factors associated with palpable fat necrosis.

RESULTS

With a median follow-up of 61 months (range: 4.3-99.5 months), 11 patients experienced palpable fat necrosis, 5 cases of which were painful. The median time to development of fat necrosis was 12.7 months (range, 3-42 months). On univariate analyses, higher V32.5-47.5 Gy (P < .05) and larger breast volume (P < .01) were predictive of any fat necrosis; higher V35-50 Gy (P < .05), receiving 2 treatments on consecutive days (P = .02), and higher Dmax (P = .01) were predictive of painful fat necrosis. On multivariate analyses, breast volume larger than 1063 cm³ remained a predictive factor for any fat necrosis; receiving 2 treatments on consecutive days and higher V45 Gy were predictive of painful fat necrosis. Breast laterality, planning target volume (PTV), race, body mass index, diabetic status, and tobacco or drug use were not significantly associated with fat necrosis on univariate analysis.

CONCLUSIONS

Early-stage breast cancer patients treated with breast conserving surgery and S-PBI in our study had a fat necrosis rate comparable to other accelerated partial breast irradiation modalities, but S-PBI is less invasive. To reduce risk of painful fat necrosis, we recommend not delivering fractions on consecutive days; limiting V42.5 < 50 cm³, V45 < 20 cm³, V47.5 < 1 cm³, Dmax ≤ 48 Gy and PTV < 100 cm³ when feasible; and counseling patients about the increased risk for fat necrosis when constraints are not met and for those with breast volume >1000 cm³.

Single-Institution Phase 1/2 Prospective Clinical Trial of Single-Fraction, High-Gradient Adjuvant Partial-Breast Irradiation for Hormone Sensitive Stage 0-I Breast Cancer

PURPOSE

We sought to evaluate the feasibility and tolerability of a novel accelerated partial breast irradiation regimen delivered in a single fraction postoperatively.

METHODS AND MATERIALS

We enrolled 50 patients with low-risk, hormone-sensitive breast cancer from 2015 to 2018 on a prospective phase 1/2 trial to receive single-fraction, high-gradient partial-breast irradiation (SFHGPBI) 2 to 8 weeks after lumpectomy for node-negative, invasive, or in situ breast cancer. The high gradient was achieved by prescribing 20 Gy to the surgical bed and 5 Gy to the breast tissue within 1 cm of the surgical bed simultaneously in 1 fraction using external beam.

RESULTS

The median age was 65 (range, 52-84). Ten patients (20%) had small-volume ductal carcinoma in situ while the remainder had stage I disease. At a median follow-up of 25 months, we evaluated toxicity, patient- and physician-reported cosmesis, patient-reported quality of life (QOL), and initial tumor control. There was no Common Terminology Criteria for Adverse Events v4.0 grade 3+ toxicity. Only 34% of patients experienced grade 1 erythema. Good-to-excellent pretreatment cosmesis was present in 100% and 98% per physicians and patients, respectively, and did not change post-SFHGPBI. Quantitative cosmesis by percentage of breast retraction assessment significantly improved over time during the post-SFHGPBI period per mixed repeated measures modeling (P = .0026). QOL per European Organization for Research and Treatment of Cancer QOL Questionnaires C30 and BR-23 did not decline other than temporarily in the systemic therapy effects and hair loss domains, both of which returned to pretreatment values. There was 1 noninvasive in-breast recurrence in a separate untreated quadrant 18 months post-SFHGPBI and 1 isolated axillary recurrence 30 months post-SFHGPBI, both salvaged successfully. There were no distant recurrences or cancer-related deaths observed.

CONCLUSIONS

Accelerated partial-breast irradiation delivered in a single fraction postoperatively using external beam techniques is a novel, feasible, well-tolerated regimen. SFHGPBI does not adversely affect cosmesis or QOL as reported by both physicians and patients. Initial tumor control rates are excellent, with longer follow-up required to confirm efficacy.

Fat Grafting and the Palpable Breast Mass in Implant-Based Breast Reconstruction: Incidence and Implications

BACKGROUND

Fat grafting is a powerful and increasingly used technique in breast reconstruction. However, fat necrosis can lead to palpable postoperative changes that can induce anxiety and lead to unplanned diagnostic studies. The authors' aim in this study was to evaluate the incidence, type, and timing of these unanticipated studies; the specialty of the ordering provider; and the factors that trigger the ordering process.

METHODS

A retrospective chart review was conducted for patients from 2006 to 2015 who underwent fat grafting as part of implant-based breast cancer reconstruction and had at least 1-year follow-up after fat grafting.

RESULTS

From 2006 to 2015, 166 patients underwent fat grafting as part of implant-based breast reconstruction. Forty-four women (26.5 percent) underwent at least one imaging procedure. Thirteen women (7.8 percent) underwent 17 biopsies. For a palpable mass, the initial imaging test most commonly ordered was ultrasound, followed by mammography/ultrasound. The percentage of patients with a diagnosis of fat necrosis on mammography, ultrasound, and biopsy was 4.2, 12.7, and 5.4 percent, respectively. Seven patients (4.2 percent) had distant metastases. Tissue diagnosis of local recurrence was never identified. Mean follow-up was 2.4 years.

CONCLUSIONS

Fat-grafting sequelae may lead to early unplanned invasive and noninvasive procedures initiated by a variety of providers. In this study, fat grafting had no impact on local recurrence rate. As use of fat grafting grows, communication among breast cancer care providers and enhanced patient and caregiver education will be increasingly important in optimizing the multidisciplinary evaluation and monitoring of palpable breast lesions.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Bone in the breast? Long term toxicity 21 years after interstitial brachytherapy as a boost

An 81-year-old patient developed an exulcerous tumor in her left breast 21 years after breast cancer treatment with lumpectomy and adjuvant radiotherapy. At the time of the initial treatment 21 years ago, whole breast irradiation was performed with a prescribed dose of 48 Gy and a maximal dose of 69 Gy. In addition, the patient received a 14.7 Gy boost with multicatheter brachytherapy as partial breast irradiation. In general, fat necrosis after radiotherapy, surgery or trauma is a minor problem for patients, but can lead to diagnostic difficulties. The incidence varies: the literature indicates that it occurs in up to 34% of cases. The direct pathogenesis is not clear; it can be due to high radiation dose to the breast, dosimetric inhomogeneities or surgical complications (seromas and inflammation). The tumor in the case described here, occurring more than two decades after the primary treatment, is a rarity in this extent and is an unusual clinical, radiological, and histological finding. It provides a good example of the need for an individualized approach to treatment.

Inverse planning and inverse implanting for breast interstitial brachytherapy. Introducing a new anatomy specific breast interstitial template (ASBIT)

An innovative template, based on thoracic cage surface reconstructions for breast interstitial brachytherapy was developed. Hybrid-inverse-planning-optimisation-based implantations and brachytherapy plans, using three custom anthropomorphic breast phantoms, were utilised for its validation. A user independent, inverse planning and inverse implanting technique is proposed.

ESTRO-ACROP guideline: Interstitial multi-catheter breast brachytherapy as Accelerated Partial Breast Irradiation alone or as boost - GEC-ESTRO Breast Cancer Working Group practical recommendations

PURPOSE

This consensus statement from the Breast Cancer Working Group of Groupe Européen de Curiethérapie of European Society for Radiotherapy and Oncology (GEC-ESTRO) aims at generating practical guidelines for multi-catheter image-guided brachytherapy in the conservative management of breast cancer patients used for either Accelerated Partial Breast Irradiation (APBI) or for a breast boost.

METHODS

Recent advances in techniques of multi-catheter brachytherapy were summarized and all the relevant literature was reviewed by a panel of experts. Panel members of the GEC-ESTRO experts participated in a series of conferences, supplemented their clinical experience, were surveyed to determine their current practices and patterns, performed a literature review, and formulated recommendations for implementing APBI with multi-catheter brachytherapy, focusing on treatment planning issues, catheter insertion, dosimetry and quality assurance. This document was reviewed and approved by the full panel, the GEC-ESTRO executive board and by the ACROP (Advisory Committee on Radiation Oncology Practice).

RESULTS

Three-dimensional (3D) treatment planning, catheter insertion techniques, dosimetry and methods of quality assurance for APBI and boost with multi-catheter image-guided brachytherapy after breast conserving surgery are described. Detailed recommendations for daily practice including dose constraints are given.

CONCLUSIONS

Recent standards and guidelines for the use of APBI with different multi-catheter image-guided brachytherapy techniques have been defined. Different techniques are used to insert the catheters. Guidelines are mandatory to assure precise catheter insertion for coverage of the target volume and to guarantee high-quality dosimetry. The same rules apply for brachytherapy based boost irradiation for breast cancer after whole breast irradiation as well as for partial breast re-irradiation.

American Brachytherapy Society consensus report for accelerated partial breast irradiation using interstitial multicatheter brachytherapy

PURPOSE

To develop a consensus report for the quality practice of accelerated partial breast irradiation (APBI) using interstitial multicatheter brachytherapy (IMB).

METHODS AND MATERIALS

The American Brachytherapy Society Board appointed an expert panel with clinical and research experience with breast brachytherapy to provide guidance for the current practice of IMB. This report is based on a comprehensive literature review with emphasis on randomized data and expertise of the panel.

RESULTS

Randomized trials have demonstrated equivalent efficacy of APBI using IMB compared with whole breast irradiation for select patients with early-stage breast cancer. Several techniques for placement of interstitial catheters are described, and importance of three-dimensional planning with appropriate optimization is reviewed. Optimal target definition is outlined. Commonly used dosing schemas include 50 Gy delivered in pulses of 0.6-0.8 Gy/h using pulsed-dose-rate technique and 34 Gy in 10 fractions, 32 Gy in eight fractions, or 30 Gy in seven fractions using high-dose-rate technique. Potential toxicities and strategies for toxicity avoidance are described in detail. Dosimetric constraints include limiting whole breast volume that receives ≥50% of prescription dose to <60%, skin dose to ≤100% of prescription dose (≤60-70% preferred), chest wall dose to ≤125% of prescription dose, Dose Homogeneity Index to >0.75 (>0.85 preferred), V₁₅₀ < 45 cc, and V₂₀₀ < 14 cc. Using an optimal implant technique coupled with optimal planning and appropriate dose constraints, a low rate of toxicity and a good-to-excellent cosmetic outcome of ≥90% is expected.

CONCLUSIONS

IMB is an effective technique to deliver APBI for appropriately selected women with early-stage breast cancer. This consensus report has been created to assist clinicians in the appropriate practice of APBI using IMB.

High-dose-rate interstitial brachytherapy for accelerated partial breast irradiation - trial results of Azerbaijan National Center of Oncology

Purpose

To describe early results of two cohorts of patients with low and intermediate risk of early breast cancer treated with accelerated partial breast irradiation (APBI) using different schedules of multicatheter brachytherapy.

Material and methods

Patients with early stage breast cancer after breast conserving surgery were enrolled for a prospective analysis. The APBI, using multicatheter brachytherapy, was delivered either eight times 4 Gy in five days with a planned total dose of 32 Gy, or seven times 5 Gy in four days with a planned total dose of 35 Gy. Primary endpoints were side effects.

Results

Forty-eight patients were enrolled between 2012 and 2014. Patients characteristics were as follow: median age of patients was 55 years, early breast cancer was defined according GEC-ESTRO recommendations. With a median follow-up period of 37 months, no significant differences regarding late side effects and cosmesis between two cohorts of patients were documented. In total, cosmesis was excellent in 13/48 (27.1%) patients, good in 34/48 (70.8%) patients, and moderate in 1/48 patient (2.1%).

Conclusions

Accelerated partial breast irradiation using multicatheter brachytherapy with 32 Gy/8 fractions and 35 Gy/7 fractions for early breast cancer seems to be similar in terms of late side effects. According to our findings, APBI was also feasible for intermediate-risk of early breast cancer patients.

Pulsed-dose-rate peri-operative brachytherapy as an interstitial boost in organ-sparing treatment of breast cancer

Purpose

To evaluate peri-operative multicatheter interstitial pulsed-dose-rate brachytherapy (PDR-BT) with an intra-operative catheter placement to boost the tumor excision site in breast cancer patients treated conservatively.

Material and methods

Between May 2002 and October 2008, 96 consecutive T1-3N0-2M0 breast cancer patients underwent breast-conserving therapy (BCT) including peri-operative PDR-BT boost, followed by whole breast external beam radiotherapy (WBRT). The BT dose of 15 Gy (1 Gy/pulse/h) was given on the following day after surgery.

Results

No increased bleeding or delayed wound healing related to the implants were observed. The only side effects included one case of temporary peri-operative breast infection and 3 cases of fat necrosis, both early and late. In 11 patients (11.4%), subsequent WBRT was omitted owing to the final pathology findings. These included eight patients who underwent mastectomy due to multiple adverse prognostic pathological features, one case of lobular carcinoma in situ, and two cases with no malignant tumor. With a median follow-up of 12 years (range: 7-14 years), among 85 patients who completed BCT, there was one ipsilateral breast tumor and one locoregional nodal recurrence. Six patients developed distant metastases and one was diagnosed with angiosarcoma within irradiated breast. The actuarial 5- and 10-year disease free survival was 90% (95% CI: 84-96%) and 87% (95% CI: 80-94%), respectively, for the patients with invasive breast cancer, and 91% (95% CI: 84-97%) and 89% (95% CI: 82-96%), respectively, for patients who completed BCT. Good cosmetic outcome by self-assessment was achieved in 58 out of 64 (91%) evaluable patients.

Conclusions

Peri-operative PDR-BT boost with intra-operative tube placement followed by EBRT is feasible and devoid of considerable toxicity, and provides excellent long-term local control. However, this strategy necessitates careful patient selection and histological confirmation of primary diagnosis.

Prospective analysis of toxicity in patients treated with strut-adjusted volume implant for early-stage breast cancer

PURPOSE

We report the toxicity of patients treated with strut-adjusted volume implant (SAVI) for accelerated partial breast irradiation treated at our institution.

METHODS AND MATERIALS

Patients treated from January 2013 to July 2015 with SAVI planned for 10 b.i.d. fractions for a total dose of 34 Gy were included. Acute and late toxicities were prospectively collected on patients in followup and graded by the Common Terminology Criteria for Adverse Events, version 4.0.

RESULTS

A total of 132 patients were included, with 1 patient having synchronous breast cancer treated in each breast. Median followup was 20.0 months (range, 2.7-37.4 months). The median age at diagnosis was 61 years (range, 41-83 years). Forty-two lesions (32%) were in situ, 88 lesions (66%) were Stage 1, and 3 (2%) lesions were Stage 2. The median planning target volume was 58.2 cc (range, 24.2-109.9 cc), median V150 was 26.3 cc (range, 11.5-47.5 cc), and median V200 was 13.0 cc (range, 6.3-26.1 cc). On a pain scale of 0-10 (10 = worst pain), pain was worst on Day 2 of treatment, with an average score of 0.46. There was one acute skin infection; there were three late skin infections, two of which was Grade 3. Other late toxicities were Grade 1 or 2: hyperpigmentation (44%), telangiectasia (0.8%), seroma (9%), fat necrosis (5%), and fibrosis (12%). Crude local recurrence rate was 4%.

CONCLUSION

SAVI is a safe treatment option for patients who are candidates for accelerated partial breast irradiation. Local control seems to be excellent, but longer followup is needed.

Validation of a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial HDR brachytherapy

PURPOSE

In current clinical practice, there is no integrated 3D ultrasound (3DUS) guidance system clinically available for breast brachytherapy. In this study, the authors present a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial high dose rate (HDR) brachytherapy treatment.

METHODS

For this work, a new computer controlled robotic 3DUS system was built to perform a hybrid motion scan, which is a combination of a 6 cm linear translation with a 30° rotation at both ends. The new 3DUS scanner was designed to fit on a modified Kuske assembly, keeping the current template grid configuration but modifying the frame to allow the mounting of the 3DUS system at several positions. A finer grid was also tested. A user interface was developed to perform image reconstruction, semiautomatic segmentation of the surgical bed as well as catheter reconstruction and tracking. A 3D string phantom was used to validate the geometric accuracy of the reconstruction. The volumetric accuracy of the system was validated with phantoms using magnetic resonance imaging (MRI) and computed tomography (CT) images. In order to accurately determine whether 3DUS can effectively replace CT for treatment planning, the authors have compared the 3DUS catheter reconstruction to the one obtained from CT images. In addition, in agarose-based phantoms, an end-to-end procedure was performed by executing six independent complete procedures with both 14 and 16 catheters, and for both standard and finer Kuske grids. Finally, in phantoms, five end-to-end procedures were performed with the final CT planning for the validation of 3DUS preplanning.

RESULTS

The 3DUS acquisition time is approximately 10 s. A paired Student t-test showed that there was no statistical significant difference between known and measured values of string separations in each direction. Both MRI and CT volume measurements were not statistically different from 3DUS volume (Student t-test: p > 0.05) and they were significantly correlated to 3DUS measurement (Pearson test: MRI p < 0.05 and CT p < 0.001). The mean angular separation distance between catheter trajectories segmented from 3DUS and CT images was 0.42° ± 0.24°, while the maximum and mean trajectory separations were 0.51 ± 0.19 and 0.37 ± 0.17 mm, respectively. Overall, the new finer grid has performed significantly better in terms of dosimetric indices. The planning target volume dosimetric indices were not found statistically different between 3DUS and CT planning (Student t-test, p > 0.05). Both the skin and the pectoral muscle dosimetric indices were within ABS guidelines.

CONCLUSIONS

A novel robot-assisted 3DUS system was designed and validated. To their knowledge, this is the first system capable of performing real-time guidance and planning of breast multicatheter HDR brachytherapy treatments. Future investigation will test the feasibility of using the system in the clinic and for permanent breast brachytherapy.

[Rare benign breast tumors including Abrikossoff tumor (granular cell tumor), erosive adenomatosis of the nipple, cytosteatonecrosis, fibromatosis (desmoid tumor), galactocele, hamartoma, hemangioma, lipoma, juvenile papillomatosis, pseudoangiomatous hyperplasia, and syringomatous adenoma: Guidelines for clinical practice]

OBJECTIVES

To provide guidelines for clinical practice from the French College of Gynaecologists and Obstetricians (CNGOF), based on the best evidence available, concerning rare benign breast tumors: Abrikossoff (granular cell tumor), erosive adenomatosis of the nipple, cytosteatonecrosis, fibromatosis (desmoid tumor), galactocele, hamartoma, hemangioma, lipoma, juvenile papillomatosis, pseudoangiomatous hyperplasia, and syringomatous adenoma.

METHODS

Bibliographical search in French and English languages by consultation of Pubmed, Cochrane and international databases.

RESULTS

For erosive adenomatosis of the nipple, surgical excision is recommended to exclude Paget's disease or cancer (grade C). When surgery is performed for breast desmoid tumor or syringomatous adenoma, free margins are recommended (grade C). Without clinico-radio-histologic discordance, surgical abstention may be proposed for Abrikossoff tumor (granular cell tumor), cytosteatonecrosis, galactocele, hamartoma, hemangioma, lipoma, juvenile papillomatosis, pseudoangiomatous hyperplasia, and syringomatous adenoma (grade C).

Accelerated Partial Breast Irradiation: A Safe, Effective, and Convenient Early Breast Cancer Treatment Option

Accelerated partial breast irradiation (APBI) is an excellent treatment option for many women with early stage breast cancer. Patient selection criteria include age over 40, status post lumpectomy, breast cancer (invasive or in situ disease) measuring <3 cm, negative margins (at least 2 mm), negative lymph nodes, and no lymphovascular space invasion. APBI is effective, well tolerated, and convenient. Women with early stage breast cancer and theii caregivers should be aware of this potential treatment option.

The incidence of fat necrosis in balloon-based breast brachytherapy

Purpose

To investigate the incidence of and potential risk factors for fat necrosis in high dose-rate (HDR) balloon-based breast brachytherapy (BBB).

Material and methods

Fifty-four patients were treated postoperatively with HDR-BBB between May 2007 and December 2010. Median age was 71 years (range: 50-88 years). Median tumor size was 1 cm (range: 0.1-2.7 cm). Forty-four had invasive histology; 43% were grade 1, 24% grade 2, and 15% grade 3. The median margin size was 0.7 cm (range: 0.1-1.5 cm).

Results

With a median follow-up of 2.9 years (range: 0.5-5.2 years), local control was 98% with one in-breast failure, and overall survival was 89%. Fifty percent of patients experienced fat necrosis. Seven patients were symptomatic, with the remainder detected by mammography alone. Two patients required surgical resection with pathology confirming fat necrosis; 1 required i.v. steroids. At 1, 3, and 5 years following treatment, estimated cumulative incidences of fat necrosis were 7.5%, 52.7%, and 60.6%. Breast laterality, location, tumor size, histology, margin size, balloon volume, skin distance, skin dose, and number of dwell positions were not significantly associated with fat necrosis on univariate analysis.

Conclusions

In this retrospective review of HDR-BBB, we found a 50% incidence of both asymptomatic and symptomatic fat necrosis. Only three patients, however, required intervention. None of the risk factors considered were significantly associated with fat necrosis. Further studies evaluating factors associated with fat necrosis for patients undergoing HDR-BBB are necessary to appropriately assess the risks associated with treatment.

Recent developments and best practice in brachytherapy treatment planning

Brachytherapy has evolved over many decades, but more recently, there have been significant changes in the way that brachytherapy is used for different treatment sites. This has been due to the development of new, technologically advanced computer planning systems and treatment delivery techniques. Modern, three-dimensional (3D) imaging modalities have been incorporated into treatment planning methods, allowing full 3D dose distributions to be computed. Treatment techniques involving online planning have emerged, allowing dose distributions to be calculated and updated in real time based on the actual clinical situation. In the case of early stage breast cancer treatment, for example, electronic brachytherapy treatment techniques are being used in which the radiation dose is delivered during the same procedure as the surgery. There have also been significant advances in treatment applicator design, which allow the use of modern 3D imaging techniques for planning, and manufacturers have begun to implement new dose calculation algorithms that will correct for applicator shielding and tissue inhomogeneities. This article aims to review the recent developments and best practice in brachytherapy techniques and treatments. It will look at how imaging developments have been incorporated into current brachytherapy treatment and how these developments have played an integral role in the modern brachytherapy era. The planning requirements for different treatments sites are reviewed as well as the future developments of brachytherapy in radiobiology and treatment planning dose calculation.

Muscle-sparing TRAM flap does not protect breast reconstruction from postmastectomy radiation damage compared with the DIEP flap

BACKGROUND

Irradiation to free flaps following immediate breast reconstruction has been shown to compromise outcomes. The authors hypothesized that irradiated muscle-sparing free transverse rectus abdominis musculocutaneous (TRAM) flaps experience less fat necrosis than irradiated deep inferior epigastric perforator (DIEP) flaps.

METHODS

The authors performed a retrospective study of all consecutive patients undergoing immediate, autologous, abdomen-based free flap breast reconstruction with muscle-sparing free TRAM or DIEP flaps over a 10-year period at their institution. Irradiated flaps (external-beam radiation therapy) after immediate breast reconstruction were compared with nonirradiated flaps. Logistic regression analysis identified potential associations between patient, tumor, and reconstructive characteristics and surgical outcomes.

RESULTS

The analysis included 625 flaps: 40 (6.4 percent) irradiated versus 585 (93.6 percent) nonirradiated. Mean follow-up for the irradiated and nonirradiated flaps was 60.0 and 48.5 months, respectively (p = 0.02). Overall complication rates were similar for both the irradiated and nonirradiated flaps. Irradiated flaps (i.e., both DIEP and muscle-sparing free TRAM flaps) developed fat necrosis at a significantly higher rate (22.5 percent) than the nonirradiated flaps (9.2 percent; p = 0.009). There were no differences in fat necrosis rates between the DIEP and muscle-sparing free TRAM flaps in both the irradiated and nonirradiated groups.

CONCLUSIONS

Both DIEP and muscle-sparing free TRAM flap reconstructions had much higher rates of fat necrosis when irradiated. Contrary to our hypothesis, the authors found that immediate breast reconstruction with a muscle-sparing free TRAM flap does not result in a lower rate of fat necrosis than reconstruction with a DIEP flap.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Fat necrosis of the breast in the accelerated partial breast irradiation era: the need for a universal grading system

Fat necrosis of the breast is increasingly reported and used as a trial endpoint in the treatment of breast cancer with accelerated partial breast irradiation (APBI). Yet, there is no universal toxicity scoring system within the latest version of the Common Terminology Criteria for Adverse Events (CTCAE v4.0). This requires investigators to adopt their own scoring system or improperly use those that exist, and limits accurate reporting of this entity. Fat necrosis of the breast also creates diagnostic uncertainty among clinicians and concern of recurrence among patients. In this review, we address the question of increasing incidence of fat necrosis through the comparison of recent APBI trials and literature. The pathogenesis, symptoms, clinical and radiologic diagnosis, clinical predictors of developing fat necrosis, management and follow-up are also discussed.Lastly, we propose a simplified and universal scoring system for the reporting of fat necrosis.

A prospective longitudinal clinical trial evaluating quality of life after breast-conserving surgery and high-dose-rate interstitial brachytherapy for early-stage breast cancer

PURPOSE

To prospectively examine quality of life (QOL) of patients with early stage breast cancer treated with accelerated partial breast irradiation (APBI) using high-dose-rate (HDR) interstitial brachytherapy.

METHODS AND MATERIALS

Between March 2004 and December 2008, 151 patients with early stage breast cancer were enrolled in a phase 2 prospective clinical trial. Eligible patients included those with Tis-T2 tumors measuring ≤3 cm excised with negative surgical margins and with no nodal involvement. Patients received 3.4 Gy twice daily to a total dose of 34 Gy. QOL was measured using European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30, version 3.0, and QLQ-BR23 questionnaires. The QLQ-C30 and QLQ-BR23 questionnaires were evaluated during pretreatment and then at 6 to 8 weeks, 3 to 4 months, 6 to 8 months, and 1 and 2 years after treatment.

RESULTS

The median follow-up was 55 months. Breast symptom scores remained stable in the months after treatment, and they significantly improved 6 to 8 months after treatment. Scores for emotional functioning, social functioning, and future perspective showed significant improvement 2 years after treatment. Symptomatic fat necrosis was associated with several changes in QOL, including increased pain, breast symptoms, systemic treatment side effects, dyspnea, and fatigue, as well as decreased role functioning, emotional functioning, and social functioning.

CONCLUSIONS

HDR multicatheter interstitial brachytherapy was well tolerated, with no significant detrimental effect on measured QOL scales/items through 2 years of follow-up. Compared to pretreatment scores, there was improvement in breast symptoms, emotional functioning, social functioning, and future perspective 2 years after treatment.