Breast Reconstruction With Postmastectomy Radiation: Choices and Tradeoffs

Effect of internal port on dose distribution in post-mastectomy radiotherapy for breast cancer patients after expander breast reconstruction

Background

In patients with expander-based reconstruction a few dosimetric analyses detected radiation therapy dose perturbation due to the internal port of an expander, potentially leading to toxicity or loss of local control. This study aimed at adding data on this field.

Materials and methods

A dosimetric analysis was conducted in 30 chest wall treatment planning without and with correction for port artifact. In plans with artifact correction density was overwritten as 1 g/cm³. Medium, minimum and maximum chest wall doses were compared in the two plans. Both plans, with and without correction, were compared on an anthropomorphic phantom with a tissue expander on the chest covered by a bolus simulating the skin. Ex vivo dosimetry was carried out on the phantom and in vivo dosimetry in three patients by using film strips during one treatment fraction. Estimated doses and measured film doses were compared.

Results

No significant differences emerged in the minimum, medium and maximum doses in the two plans, without and with correction for port artifacts. Ex vivo and in vivo analyses showed a good correspondence between detected and calculated doses without and with correction.

Conclusions

The port did not significantly affect dose distribution in patients who will receive post-mastectomy radiation therapy.

Dosimetric and Clinical Factors Associated with Breast Reconstruction Complications in Patients Receiving Post-Mastectomy Radiation

PURPOSE/OBJECTIVE(S)

Approximately 30% of women who receive post-mastectomy radiation therapy (PMRT) in the setting of breast reconstruction suffer from reconstruction complications. This study aims to assess clinical and dosimetric factors associated with the risk of reconstruction complications after PMRT, with the ultimate goal of identifying a dosimetric constraint that can be utilized clinically to limit this risk.

MATERIALS/METHODS

We retrospectively identified 41 patients who underwent modified radical (MRM) or total mastectomy followed by immediate or delayed reconstruction (autologous or implant-based) and radiation at a single institution from 2014-2020. Reconstruction complications were defined as flap or implant failure, necrosis, capsular contracture, cellulitis/infection, implant rupture, implant malposition, leakage/rupture, unplanned operation, and hematoma/seroma. Clinical and dosimetric variables associated with complications were assessed with univariate analyses.

RESULTS

12 patients (29%) suffered reconstruction complications which led to flap or implant failure in 5 patients. Median time to complication following reconstruction was 8 months. 32% of patients with immediate and 20% with delayed reconstruction suffered a complication, respectively. There were no local failures. Smoking (p=0.02), use of bolus (p=0.03), and V107 > 11% (p=0.03) were associated with increased complication rates. The complication rates were 42% when V107 > 11% versus 12% when V107 < 11%; 58% in smokers versus 17% in nonsmokers; and 42% with bolus versus 7% without.

CONCLUSION

Plan heterogeneity appears to be associated with the risk of reconstruction complications. Pending further validation, V107 < 11% may serve as a reasonable guide to limit this risk. Further consideration should be given to the selective use of bolus in this setting and optimization of clinical factors such as smoking cessation.

Lipotransfer Strategies and Techniques to Achieve Successful Breast Reconstruction in the Radiated Breast

Radiation therapy is frequently a critical component of breast cancer care but carries with it side effects that are particularly damaging to reconstructive efforts. Autologous lipotransfer has the ability to improve radiated skin throughout the body due to the pluripotent stem cells and multiple growth factors transferred therein. The oncologic safety of lipotransfer to the breasts is demonstrated in the literature and is frequently considered an adjunctive procedure for improving the aesthetic outcomes of breast reconstruction. Using lipotransfer as an integral rather than adjunctive step in the reconstructive process for breast cancer patients requiring radiation results in improved complication rates equivalent to those of nonradiated breasts, expanding options in these otherwise complicated cases. Herein, we provide a detailed review of the cellular toxicity conferred by radiotherapy and describe at length our approach to autologous lipotransfer in radiated breasts.

The 2018 assisi think tank meeting on breast cancer: International expert panel white paper

We report on the second Assisi Think Tank Meeting (ATTM) on breast cancer which was held under the auspices of the European Society for RadioTherapy & Oncology (ESTRO). In discussing in-depth current evidence and practice it was designed to identify grey areas in diverse forms of the disease. It aimed at addressing uncertainties and proposing future trials to improve patient care. Before the meeting, three key topics were selected: 1) primary systemic therapy, mastectomy, breast reconstruction and post-mastectomy radiation therapy, 2) therapeutic options in ductal carcinoma in situ, and 3) therapy de-escalation in early stage breast cancer. Clinical practice in these areas was investigated by means of an online questionnaire. The time lapse period between the survey and the meeting was used to review the literature and on-going clinical trials. At the ATTM both were discussed in depth and research protocols were proposed.

Successful Immediate Staged Breast Reconstruction with Intermediary Autologous Lipotransfer in Irradiated Patients

As indications for radiotherapy in mastectomized patients grow, the need for greater reconstructive options is critical. Preliminary research suggests an ameliorating impact of lipotransfer on irradiated patients with expander-to-implant reconstruction. Herein, we present our technique using lipotransfer during the expansion stage to facilitate implant placement.

ESTRO ACROP consensus guideline for target volume delineation in the setting of postmastectomy radiation therapy after implant-based immediate reconstruction for early stage breast cancer

Immediate breast reconstruction (IBR) rates after mastectomy are increasing. Postmastectomy radiation therapy (PMRT) contouring guidelines for target volumes in the setting of IBR are lacking. Therefore, many patients who have had IBR receive PMRT to target volumes similar to conventional simulator-based whole breast irradiation. The aim of this paper is to describe delineation guidelines for PMRT after implant-based IBR based on a thorough understanding of the surgical procedures, disease stage, patterns of recurrence and radiation techniques. They are based on a consensus endorsed by a global multidisciplinary group of breast cancer experts.

Optimise not compromise: The importance of a multidisciplinary breast cancer patient pathway in the era of oncoplastic and reconstructive surgery

Modern breast cancer care is a complex multidisciplinary undertaking in which the integrated function of multiple constituent parts is critical, and where changes to one therapeutic component may profoundly influence the delivery and outcomes of another. Oncoplastic and reconstructive breast surgery has evolved in the era of longer survival rates for women with breast cancer and aims to enhance oncological and cosmetic outcomes. However, concurrently there has been an expansion in the indications for post-mastectomy radiation therapy (Abdulkarim et al., 2011; Early Breast Cancer Trialists' Collaborative Group (EBCTCG), 2014; Poortmans et al., 2015; Wang et al., 2011), the recognition of several biologically distinct breast cancer subtypes (Perou et al., 2000; Sørlie et al., 2001, 2003; Cheang et al., 2008, 2009; Sotiriou et al., 2003; Millar et al., 2011; Blows et al., 2010; Schnitt, 2010; Haque et al., 2012; Dai et al., 2015) and the development of recommendations for prophylactic surgery for high-risk women, including BRCA-mutation carriers (James et al., 2006; Domchek et al., 2010). Primary systemic therapy is increasingly utilised yet has varying efficacy depending on tumour biology (Cortazar et al., 2014). In this paper we review the evidence which informs the multidisciplinary team opinion in the era of oncoplastic and reconstructive breast surgery. We aim to describe an optimal multidisciplinary approach which balances competing risks of multimodal therapies to optimise oncological and cosmetic outcomes.