Immediate tissue expander or implant-based breast reconstruction does not compromise the oncologic delivery of post-mastectomy radiotherapy (PMRT)

Postmastectomy radiotherapy in breast reconstruction: Current controversies and trends

Breast cancer is the most common cancer among women worldwide. Postmastectomy radiotherapy (PMRT) is an essential component of combined therapy for early-stage, high-risk breast cancer. Breast reconstruction (BR) is often considered for patients with breast cancer who have undergone mastectomy. There has been a considerable amount of discussion about the optimal approach to combining PMRT with BR in the treatment of breast cancer. PMRT may increase the risk of complications and prevent good aesthetic results after BR, while BR may increase the complexity of PMRT and the radiation dose to surrounding normal tissues. The purpose of this review is to give a broad overview and summary of the current controversies and trends in PMRT and BR in the context of the most recent literature available.

Oncologic Safety of One-Stage Implant-Based Breast Reconstruction in Breast Cancer Patients With Positive Sentinel Lymph Nodes: A Single-Center Retrospective Study Using Propensity Score Matching

OBJECTIVE

The purpose of this study is to evaluate the oncologic safety of one-stage implant-based breast reconstruction (OIBR) following mastectomy in breast cancer patients with positive sentinel lymph nodes (SLNs).

METHODS

We collected clinical and pathological data from breast cancer patients with positive SLNs who underwent OIBR or not after mastectomy between January 2015 and December 2018. A total of 194 patients were included, with 130 patients undergoing mastectomy alone (MA) and 64 patients receiving OIBR after mastectomy. The clinical and pathological features, as well as the postoperative oncologic outcomes, of the 2 groups were retrospectively analyzed. Propensity score matching (PSM) was employed to mitigate the effects of data bias and confounding factors.

RESULTS

The median follow-up time was 66 months for the OIBR group and 64 months for the MA group after PSM. The majority of reconstructive surgeries use an approach of prosthetic implantation (52.0%). This is followed by prosthetic implantation combined with a latissimus dorsi (LD) flap (32.0%), and acellular dermal matrix (ADM)-assisted implant placement (16.0%). During the follow-up period, a local recurrence was observed in 1 case, regional recurrence in 3 cases, and distant metastasis leading to death in 3 cases among the OIBR group patients. No significant difference was found between the OIBR and MA groups in disease-free survival (DFS) (P = .66), distant metastasis-free survival (DMFS) (P = .91), locoregional recurrence-free survival (LRRFS) (P = .44), and overall survival (OS) (P = .57).

CONCLUSION

OIBR is a safe option for breast cancer patients with positive SLNs and does not negatively impact cancer recurrence or overall survival.

Anatomic Location of Tissue Expander Placement Is Not Associated With Delay in Adjuvant Therapy in Women With Breast Cancer

BACKGROUND

Tissue expanders in breast reconstruction are traditionally placed retropectoral. Increasingly, patients are undergoing prepectoral placement. The impact of this placement on the initiation of adjuvant treatment is unknown.

METHODS

A retrospective review was conducted to identify women diagnosed with breast cancer who underwent mastectomy followed by radiation and/or chemotherapy. Women were divided into 3 groups: prepectoral tissue expander placement, retropectoral tissue expander placement, and no immediate reconstruction. A treatment delay was defined as greater than 8 weeks between tissue expander placement and adjuvant therapy.

RESULTS

Of 634 women, 205 (32%) underwent tissue expander placement, and 429 (68%) did not have immediate reconstruction. Of those with tissue expanders placed, 84 (41%) had prepectoral placement, and 121 (59%) had retropectoral placement. The median time to adjuvant therapy was 49 days for the entire cohort: no reconstruction, 47 days; prepectoral, 57 days; and retropectoral, 55 days. Treatment delays were observed in 34% of women: no reconstruction, 28%; prepectoral, 51%; and retropectoral, 46% ( P < 0.001). Tissue expander placement was associated with a delay to adjuvant therapy when compared with no reconstruction ( P < 0.001). The location of the tissue expander did not impact the odds of having a delay. On multivariable analysis, having reconstruction, having postoperative infection, not undergoing chemotherapy treatment, and being a current smoker were associated with a delay to adjuvant therapy. A delay to treatment was not associated with worse survival.

CONCLUSIONS

Placement of a tissue expander delayed adjuvant therapy. The location of tissue expander placement, retropectoral versus prepectoral, did not impact the time to adjuvant treatment.

Radiotherapy dosimetry and radiotherapy related complications of immediate implant-based reconstruction after breast cancer surgery

Backgrounds

The impact of immediate implant-based breast reconstruction (IBBR) on the delivery of radiotherapy plans remains controversial. This study aimed to compare the differences in radiotherapy dosimetry, complications of radiotherapy, and quality of life in patients who underwent modified radical mastectomy combined with or without IBBR.

Methods

We retrospectively collected 104 patients with breast cancer who underwent intensity-modulated radiation therapy after modified radical mastectomy with IBBR (n =46) or not (n =58) from January 2017 to December 2021. The dosimetric differences in radiotherapy of planning target volume (PTV) and organs at risk and the differences in complications of radiotherapy between the two groups were compared. We also applied the functional assessment of cancer therapy-breast cancer (FACT-B) score to compare the difference in quality of life. The chi-square test and independent samples t-test were used to analyze the above data.

Results

IBBR group was associated with higher PTV volumes, PTV D98, V95, and lower PTV Dmean, D2 compared with the non-reconstruction group (P<0.05). IBBR group also had lower radiotherapy dosimetric parameters in the ipsilateral lung and the heart of left breast cancer patients. The differences in the rates of radiation pneumonia (RP) and radiation dermatitis (RD) between the two groups were not statistically significant (P > 0.05). Moreover, FACT-B scores at 6 months after radiotherapy in patients with IBBR were higher than those without reconstruction (P < 0.05).

Conclusion

Patients with IBBR achieved better radiation dosimetry distribution and higher quality of life without more complications of radiotherapy.

Post-mastectomy radiation therapy with helical tomotherapy in patients with or without immediate implant-based reconstruction: a single institution experience

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We report very low doses to the heart and lung for PMRT with Helical Tomotherapy.

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Breast implant improves dosimetric results with reduced heart and lung doses.

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No local recurrence was seen in the posterior part of implants.

Introduction

We report on our experience of using Helical Tomotherapy (HT) in the context of post-mastectomy radiation therapy (PMRT) with or without immediate implant-based breast Reconstruction (IBR).

Material and methods

The study included a total of 173 patients who underwent PMRT with HT between 2013 and 2015 in our institution (87 immediate breast reconstructions with retropectoral implants (IBR + ), 86 without reconstructions (IBR-)). The chest wall target volume included subcutaneous tissue and pectoralis muscle and excluded the posterior region of the implant as well as the ribs.

Results

Median time to initiation of the first adjuvant treatment from mastectomy was similar between the two groups (p = 0.134). Dose coverage to the chest wall was significantly improved for the IBR + group (V95% = 95.1 % versus 92.0 %; p < 0.0001). The irradiated volume of the ipsilateral lung was significantly decreased in the IBR + group with a median V20Gy of 11.6 %, compared to 15.2 % for the control group (p < 0.0001). The median heart V15Gy was also significantly lower in the IBR + group than in the control group (1.7 vs 2.5 %; p = 0.0280). The reconstruction failure rate was 14.9% (n = 13). After a median follow-up of 65 months, loco regional recurrence rate was low in both groups: 3 patients (3.4%) in the IBR + group and 5 patients (5.8%) in the control group, without any local recurrence in the posterior part of the implant.

Conclusions

The presence of a breast implant reduces cardiac and pulmonary doses during Tomotherapy irradiation, without compromising oncological outcomes.

Immediate breast reconstruction has no impact on the oncologic outcomes of patients treated with post-mastectomy radiation therapy: a comparative analysis based on propensity score matching

PURPOSE

To investigate the impact of immediate breast reconstruction (iBR) on patients treated with post-mastectomy radiation therapy (PMRT) using propensity score matching (PSM).

METHODS

After a retrospective review of patients treated with PMRT between 2008 and 2017, we included 153 patients who underwent iBR and 872 patients who did not undergo iBR. Among the 153 patients who underwent iBR, 34 received one-stage iBR with autologous tissue and 119 received two-stage iBR. Conventional fractionated PMRT with a total dose of 50-50.4 Gy in 25-28 fractions was performed in all patients. Propensity scores were calculated via logistic regression.

RESULTS

Patients who underwent iBR were younger, had early stage disease, and had more frequent hormone receptor-positive tumor than those who did not undergo iBR. After PSM, 127 patients from each group with well-balanced characteristics were selected. With a median follow-up of 67.5 months, iBR led to better 6-year disease-free survival rates compared to no iBR before PSM (84.8% vs. 71.4%, p = 0.003); after PSM, there was no significant difference (84.8% vs. 75.5%, p = 0.130). On multivariable analysis in the matched cohort, iBR was not associated with inferior disease-free survival (hazard ratio, 0.67; p = 0.175). In the sensitivity analysis, iBR was not associated with a lower disease-free survival across all prognostic groups. The 5-year cumulative incidence of iBR failure was 15.0%.

CONCLUSION

In patients with adverse pathologic factors planning to receive PMRT, iBR did not compromise oncologic outcomes. In addition, iBR can be considered in patients treated with PMRT with several clinicopathologic risk factors.

Proton Therapy for Breast Cancer: A Consensus Statement From the Particle Therapy Cooperative Group Breast Cancer Subcommittee

Radiation therapy plays an important role in the multidisciplinary management of breast cancer. Recent years have seen improvements in breast cancer survival and a greater appreciation of potential long-term morbidity associated with the dose and volume of irradiated organs. Proton therapy reduces the dose to nontarget structures while optimizing target coverage. However, there remain additional financial costs associated with proton therapy, despite reductions over time, and studies have yet to demonstrate that protons improve upon the treatment outcomes achieved with photon radiation therapy. There remains considerable heterogeneity in proton patient selection and techniques, and the rapid technological advances in the field have the potential to affect evidence evaluation, given the long latency period for breast cancer radiation therapy recurrence and late effects. In this consensus statement, we assess the data available to the radiation oncology community of proton therapy for breast cancer, provide expert consensus recommendations on indications and technique, and highlight ongoing trials' cost-effectiveness analyses and key areas for future research.

Implant risk failure in patients undergoing postmastectomy 3-week hypofractionated radiotherapy after immediate reconstruction

AIM

To evaluate reconstruction failure (RF) rate in patients receiving implant-based immediate breast reconstruction (IBR) and hypofractionated (HF) postmastectomy radiation therapy (PMRT).

MATERIALS AND METHODS

Stage II-III breast cancer patients, treated with HF-PMRT using intensity modulated radiotherapy were stratified in two groups according to IBR: single-stage direct-to-implant (DTI-group) and two-stage expander and implant (TE/I-group). Irradiated patients were matched with non-irradiated ones who underwent the same IBR during the same period. Prescription dose was 40.05 Gy/15 fractions to chest wall and infra/supraclavicular nodal region. Primary endpoint was RF defined as the need of major revisional surgery (MaRS) for implant removal or conversion to autologous reconstruction. Secondary endpoint was the rate of minor revisional surgeries (MiRS) including implant repositioning or substitution with another implant.

RESULTS

One hundred and seven irradiated patients (62 in TE/I-group, 45 in DTI-group) were matched with 107 non-irradiated subjects. Median follow-up was 4.2 years (0.1-6.1) In the TE/I setting, MaRS was performed in 8/62 irradiated patients (12.9%) of the irradiated TE/I group compared to 1/62 (1.6%) non-irradiated subjects (p = 0.015). In the DTI setting, MaRs occurred in 3/45 irradiated patients (6.7%) compared to 1/45 non-irradiated ones (2.2%) (p = 0.35). Overall MaRS rate was 10.3% in the irradiated group. MiRS was performed in 35.6% and 31.1% of the irradiated and non-irradiated DTI-groups (p = 0.65), respectively, and in 12.9% and 8.1% of the irradiated and non-irradiated TE/I groups (p = 0.38), respectively.

CONCLUSIONS

Compared to the non-irradiated counterparts, the TE/I group showed higher rate of RF, while no statistically significant difference was observed for the DTI group. The use of hypofractionation and IMRT to implant-based IBR did not seem to increase the risk of RF which appeared to be in line with the literature.

Does chemotherapy or radiotherapy affect the postoperative complication in breast cancer patients who underwent immediate breast reconstruction with tissue expander?

BACKGROUND

Immediate breast reconstruction with tissue expander in breast cancer patients who were expected to receive adjuvant therapy, such as chemotherapy or radiotherapy, has been a topic of debate. Postoperative complications from tissue expander procedures can delay the timing of adjuvant treatment and subsequently increase the probability of recurrence. The purpose of this study was to identify the impact of chemotherapy and radiotherapy on postoperative complications in patients who underwent immediate reconstruction (IR) using tissue expander.

METHODS

We conducted a retrospective study of 1081 breast cancer patients who underwent mastectomy and IR using tissue expander insertion between 2012 and 2017 in Samsung Medical Center. The patients were divided into two groups based on complications (complication group vs. no complication group). Complication group was regarded to have surgical removal or conservative treatment based on clinical findings such as infection, capsular contracture, seroma, hematoma, rupture, malposition, tissue viability, or cosmetic problem. The complication group had 59 patients (5.5%) and the no complication group had 1022 patients (94.5%).

RESULTS

In univariate analysis, adjuvant radiotherapy and adjuvant chemotherapy were significantly associated with postoperative complications. In multivariate analysis, however, only higher pathologic N stage was significantly associated with postoperative complications (p < 0.001). Chemotherapy (p = 0.775) or radiotherapy (p = 0.825) were not risk factors for postoperative complications.

CONCLUSIONS

IR with tissue expander after mastectomy may be a treatment option even when the patients are expected to receive adjuvant chemotherapy or radiotherapy. These results will aid patients who are concerned about the complications of IR caused by chemotherapy or radiotherapy determine whether or not to have IR.

TRIAL REGISTRATION

Patients were selected and registered retrospectively, and medical records were evaluated.

A Retrospective Dosimetric Analysis of the New ESTRO-ACROP Target Volume Delineation Guidelines for Postmastectomy Volumetric Modulated Arc Therapy After Implant-Based Immediate Breast Reconstruction

Purpose: The European Society of Radiation & Oncology and Advisory Committee on Radiation Oncology Practice (ESTRO-ACROP) presented new guidelines for clinical target volume (CTV) delineation in post-mastectomy radiation therapy (PMRT) after implant-based immediate breast reconstruction (IBR-i). This study evaluated the dosimetric characteristics, dosimetric accuracy, and delivery accuracy of these guidelines in volumetric modulated arc therapy (VMAT). Methods and Materials: This retrospective study included 15 patients with left breast cancer who underwent mastectomy with tissue expander placement followed by PMRT. An experienced radiation oncologist delineated the CTV twice on the same image datasets based on the ESTRO-ACROP (EA-TVD) and conventional target volume delineation (C-TVD) guidelines. All VMAT plans, which used a double partial arc, were generated using six MV photons. Clinically relevant dose-volume parameters for organs at risk were compared. Dosimetric accuracy of the treatment plans and delivery accuracy were assessed. Results: Target volume of EA-TVD was significantly smaller than that of C-TVD. Although no statistically significant difference was noted in the target coverage between the two VMAT plans, EA-TVD VMAT significantly reduced the mean heart dose (3.99 ± 1.02 vs. 5.84 ± 1.78 Gy, p = 0.000), the maximum left anterior descending coronary artery (LAD) dose (9.43 ± 3.04 vs. 13.97 ± 6.04 Gy, p = 0.026), and the mean LAD dose (4.52 ± 1.31 vs. 6.35 ± 2.79 Gy, p = 0.028) compared with C-TVD VMAT. No significant difference was observed with respect to the total monitor units, plan complexity, and delivery quality assurance. Conclusions: This is the first study to show significant dose reduction for the normal heart and LAD tissue offered by the EA-TVD, while maintaining dosimetric and delivery accuracy, in PMRT after IBR-i in VMAT for left-sided breast cancer patients.

Higher reconstruction failure and less patient-reported satisfaction after post mastectomy radiotherapy with immediate implant-based breast reconstruction compared to immediate autologous breast reconstruction

PURPOSE

To improve shared decision making, clinical- and patient-reported outcomes between immediate implant-based and autologous breast reconstruction followed by postmastectomy radiotherapy (PMRT) were compared.

METHODS

All women with in situ and/or invasive breast cancer who underwent skin sparing mastectomy with immediate breast reconstruction (IBR) (autologous- or implant based, one- or two staged) followed by PMRT in the Utrecht region between 2012 and 2016 were selected from the Netherlands Cancer Registry, of which 112 (59%) agreed to participate. The primary outcome was reconstruction failure after the start of radiotherapy, and secondary outcomes were patient-reported outcomes measured with BREAST-Q.

RESULTS

109 patients underwent skin-sparing mastectomy, of which 29 (27%) underwent immediate autologous reconstruction and 80 (73%) received immediate implant-based reconstruction. After PMRT, reconstruction failure occurred in 17 patients (21%) with implant-based reconstruction, while no failure was seen in the autologous group (p = 0.04). Mean patient-reported 'Satisfaction with Breasts' (50.9 vs. 63.7, p = 0.001) and 'Sexual Well-being' (46.0 vs. 55.5, p = 0.037) were lower after implant-based reconstruction compared to autologous reconstruction. Thirteen patients with autologous flaps underwent surgical cosmetic corrections compared to ten patients in the implant group (45 vs. 13%, p = 0.001). IBR and PMRT in this study resulted in a high rate of severe capsular contraction in implant-based reconstruction (16.9%) and fibrosis in autologous reconstruction (13.8%).

CONCLUSIONS

Patients treated with PMRT and one or two stage immediate implant-based reconstruction were at greater risk of developing reconstruction failure and were less satisfied when compared to one or two stage immediate autologous reconstruction. Since fairly high complication rates in both reconstruction methods after PMRT are observed, it raises the question whether immediate breast reconstruction should be considered at all when PMRT is indicated. Patients considering or potential candidates for IBR should be informed about the consequences of PMRT and especially when opting for autologous reconstruction one should possibly perform reconstruction in a secondary setting.

International multidisciplinary expert panel consensus on breast reconstruction and radiotherapy

BACKGROUND

Conflicting evidence challenges clinical decision-making when breast reconstruction is considered in the context of radiotherapy. Current literature was evaluated and key statements on topical issues were generated and discussed by an expert panel at the International Oncoplastic Breast Surgery Meeting in Milan 2017.

METHODS

Studies on radiotherapy and breast reconstruction (1985 to September 2017) were screened using MEDLINE, Embase and CENTRAL. The literature review yielded 30 controversial key questions. A set of key statements was derived and the highest levels of clinical evidence (LoE) for each of these were summarized. Nineteen panellists convened for dedicated discussions at the International Oncoplastic Breast Surgery Meeting to express agreement, disagreement or abstention for the generated key statements.

RESULTS

The literature review identified 1522 peer-reviewed publications. A list of 22 key statements was produced, with the highest LoE recorded for each statement. These ranged from II to IV, with most statements (11 of 22, 50 per cent) supported by LoE III. There was full consensus for nine (41 per cent) of the 22 key statements, and more than 75 per cent agreement was reached for half (11 of 22).

CONCLUSION

Poor evidence exists on which to base patient-informed consent. Low-quality studies are conflicting with wide-ranging treatment options, precluding expert consensus regarding optimal type and timing of breast reconstruction in the context of radiotherapy. There is a need for high-quality evidence from prospective registries and randomized trials in this field.

Post-mastectomy intensity modulated proton therapy after immediate breast reconstruction: Initial report of reconstruction outcomes and predictors of complications

PURPOSE

To report reconstructive outcomes of patients treated with post-mastectomy intensity modulated proton therapy (IMPT) following immediate breast reconstruction (IBR).

MATERIALS AND METHODS

Consecutive women with breast cancer who underwent implant-based IBR and post-mastectomy IMPT were included. Clinical characteristics, dosimetry, and acute toxicity were collected prospectively and reconstruction complications retrospectively.

RESULTS

Fifty-one women were treated between 2015 and 2017. Forty-two had bilateral reconstruction with unilateral IMPT. The non-irradiated contralateral breasts served as controls. Conventional fractionation (median 50 Gy/25 fractions) was administered in 37 (73%) and hypofractionation (median 40.5 Gy/15 fractions) in 14 (27%) patients. Median mean heart, ipsilateral lung V20Gy, and CTV-IMN V95% were 0.6 Gy, 13.9%, and 97.4%. Maximal acute dermatitis grade was 1 in 32 (63%), 2 in 17 (33%), and 3 in 2 (4%) patients. Surgical site infection (hazard ratio [HR] 13.19, 95% confidence interval [CI] 1.67-104.03, p = 0.0012), and unplanned surgical intervention (HR 9.86, 95% CI 1.24-78.67, p = 0.0068) were more common in irradiated breasts. Eight of 51 irradiated breasts and 2 of 42 non-irradiated breasts had reconstruction failure (HR 3.59, 95% CI 0.78-16.41, p = 0.084). Among irradiated breasts, hypofractionation was significantly associated with reconstruction failure (HR 4.99, 95% CI 1.24-20.05, p = 0.024), as was older patient age (HR 1.14, 95% CI 1.05-1.24, p = 0.002).

CONCLUSIONS

IMPT following IBR spared underlying organs and had low rates of acute toxicity. Reconstruction complications are more common in irradiated breasts, and reconstructive outcomes appear comparable with photon literature. Hypofractionation was associated with higher reconstruction failure rates. Further investigation of optimal dose-fractionation after IBR is needed.

Prepectoral Direct-to-Implant Breast Reconstruction: Early Outcomes and Analysis of Postoperative Pain

BACKGROUND

Direct-to-implant (DTI) breast reconstruction provides high-quality aesthetic results in appropriate candidates. Most commonly, implants are placed in the subpectoral space which can lead to pain and breast animation. Surgical and technological advances have allowed for successful prepectoral implant placement which may eliminate these trade-offs.

OBJECTIVES

Here we present early outcomes from 153 reconstructions in 94 patients who underwent prepectoral DTI. We sought to determine whether these patients have less postoperative pain and narcotic use than subpectoral implant or expander placement.

METHODS

A retrospective review was performed for all prepectoral DTI reconstructions at our institution from 2015 to 2016. Data were collected on postoperative pain and narcotic use while in hospital.

RESULTS

The average follow-up time was 8.5 months (range, 3-17 months) and the overall complication rate was 27% (n = 41) with the most common complications being skin necrosis (9%, n = 13) and infection (7%, n = 11). No statistically significant difference in complications was found in patients who underwent postmastectomy radiation therapy. Patients who underwent prepectoral DTI reconstruction did not have a statistically significant difference in postoperative pain and narcotic use while in-hospital compared with other techniques.

CONCLUSION

Prepectoral DTI reconstruction provides good results with similar complication rates to subpectoral techniques. Prepectoral DTI eliminates the problem of breast animation. Although our series did not reach statistical significance in pain scores or requirement for postoperative narcotics, we believe that it is an important preliminary result and with larger numbers we anticipate a more definitive conclusion.

LEVEL OF EVIDENCE 4

The impact on Australian women of lack of choice of breast reconstruction options: A qualitative study

BACKGROUND

Many studies have demonstrated the positive impact of breast reconstruction (BR) on women following mastectomy for breast cancer. However, women's preferences for BR are not always considered by surgeons prior to mastectomy. The aim of this research is threefold: to document the negative impact lack of choice has had on some Australian women; to explore potential reasons for the absence of informed discussion; and to develop a prompt list of discussion topics to aid informed decision making.

METHODS

This research is part of a larger study using semistructured telephone or face-to-face interviews with women with breast cancer, surgeons, and health professionals to explore ways of improving access to BR. This article focuses on responses from all 22 women who reported negative BR experiences and seven of 31 surgeons who had made comments relevant to limiting BR discussion and choice.

RESULTS

The impact of a lack of information or choice at the time of mastectomy was often extreme and long-term. Breast surgeons are the gate keepers to accessing BR but too often appeared to limit women's choices. Interviews revealed cases where BR was not offered prior to mastectomy, even though it was available locally; where BR was not available locally, but patients were not informed about BR options available in other locations; where only delayed BR options were discussed; and where the type of BR being offered did not match patient preferences.

CONCLUSION

We have suggested essential BR discussion points to be raised with all clinically eligible women interested in considering BR.

Tamoxifen-Prefabricated Beige Adipose Tissue Improves Fat Graft Survival in Mice

BACKGROUND

Fat grafting has become an important tool for breast reconstruction in breast cancer patients. Tamoxifen, the hormone therapy agent most frequently used for breast cancer, can affect adipose metabolism and cause browning of adipose tissue. This study hypothesized that tamoxifen could increase fat graft survival by altering adipose metabolism.

METHODS

C57/BL6 mice were divided into three groups receiving different treatments before and after fat grafting. The tamoxifen/grafting/tamoxifen group was pretreated with daily tamoxifen for 8 weeks, received fat grafting, and was treated with daily tamoxifen. The graft/tamoxifen group was pretreated with daily phosphate-buffered saline for 8 weeks, received fat grafting, and was treated with daily tamoxifen. The control group was pretreated with daily phosphate-buffered saline for 8 weeks, received fat grafting, and was treated with daily phosphate-buffered saline. The inguinal fat used for transplantation and the transferred fat at weeks 4 and 12 after transplantation were harvested and analyzed.

RESULTS

Tamoxifen-pretreated inguinal fat showed beige fat features, with smaller adipocyte size, up-regulated uncoupling protein 1 expression, and improved vascularization. The retention rate of transferred fat was significantly higher in the tamoxifen/grafting/tamoxifen group than in the control group (69 ± 12 percent versus 36 ± 13 percent; p < 0.05), but fat grafts in the graft/tamoxifen group had a retention rate similar to that in the control group (31 ± 12 percent versus 36 ± 13 percent; p > 0.05). Improved angiogenesis and increased vascular endothelial growth factor expression were found in the tamoxifen/grafting/tamoxifen group but not in the graft/tamoxifen group.

CONCLUSIONS

Tamoxifen treatment before fat grafting resulted in prefabricated vascularized beige fat with small adipocytes, which greatly improve fat graft survival. However, tamoxifen after fat grafting did not affect fat graft evolution.

Prepectoral Implant-Based Breast Reconstruction with Postmastectomy Radiation Therapy

BACKGROUND

Two-stage subpectoral implant-based breast reconstruction is the most common method for breast reconstruction. Recent advances in surgical techniques and technology have made prepectoral implant-based breast reconstruction feasible. There are limited data on outcomes after prepectoral implant-based breast reconstruction and postmastectomy radiation therapy.

METHODS

A retrospective review of consecutive patients undergoing immediate two-stage prepectoral implant-based breast reconstruction with postmastectomy radiation therapy was performed. Outcomes of irradiated breasts were compared with nonirradiated breasts in bilateral cases.

RESULTS

Ninety-three cases of prepectoral implant-based breast reconstruction in 54 women who underwent immediate two-stage reconstruction (39 bilateral and 15 unilateral) and unilateral postmastectomy radiation therapy were identified. Mean follow-up was 19 months from mastectomy and tissue expander reconstruction and 9 months from implant placement. Crude complication rates in irradiated versus nonirradiated sides were as follows: surgical-site infection, 18.5 percent versus 7.7 percent; seroma, 5.6 percent versus 5.1 percent; mastectomy skin flap necrosis, 1.9 percent versus 2.6 percent; wound dehiscence, 1.9 percent versus 7.7 percent; capsular contracture, 1.9 percent versus 0 percent; hematoma, 1.9 percent versus 2.6 percent; and extrusion, 1.9 percent versus 0 percent. On univariate analysis, there were no risk factors associated with any complication, including radiation therapy, surgical-site infection, unplanned readmissions, and unplanned return to the operating room. To date, reconstruction has been completed in 96 percent of patients, with successful implant-based breast reconstruction in 81 breasts (45 irradiated breasts and 36 nonirradiated breasts).

CONCLUSIONS

Early data of prepectoral implant-based breast reconstruction in patients with postmastectomy radiation therapy show promising results. Postmastectomy radiation therapy should not be an absolute contraindication to prepectoral implant-based breast reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Cardiovascular Concerns in BRCA1 and BRCA2 Mutation Carriers

PURPOSE OF REVIEW

BRCA1 and BRCA2 mutation carriers can be at increased cardiovascular risk. The goal of this review is to provide information about factors associated with increased cardiovascular risk, methods to prevent cardiovascular toxicities, and recommended screening guidelines.

RECENT FINDINGS

BRCA1/2 mutation carriers who are diagnosed with cancer are often exposed to chemotherapy, chest radiotherapy, and/or HER2 directed therapies, all of which can be cardiotoxic. In addition, BRCA1/2 carriers often undergo prophylactic salpingoopherectomies, which may also increase cardiovascular risks. Understanding the potential for increased cardiovascular risk in individuals with a BRCA1 or BRCA2 mutation, as well as gold standard practices for prevention, detection, and treatment of cardiac concerns in this population, is important.