Evaluation of Dual-port versus Single-port Tissue Expanders in Postmastectomy Breast Reconstruction

Evaluation of a non-metallic dual-port expander for intensity modulated proton therapy

PURPOSE

To provide a methodology for characterization of the technical properties of a newly developed non-metallic tissue expander for intensity modulated proton therapy.

METHODS

Three tissue expanders (AlloX2-Pro: plastic-dual port, AlloX2: metal-dual port, and Dermaspan: metal-single port) were deconstructed, CT-scanned, and modeled in RayStation12A. A 165 MeV single spot was used to create RayStation dose planes, and the integrated depth dose profiles were calculated and the DR90 extracted to predict water equivalent thickness (WET). These predictions were compared to measurements taken with an IBA Giraffe MLIC. Native, water, and fully modelled overrides were compared for the AlloX2 Pro to quantify differences in override choices. Geometric considerations between expanders were compared using a ray-tracing technique to contour the "no-fly" zone around metallic components using a clinical, three beam arrangement. Lastly, a planning and evaluation framework was provided using a single plan as an illustration.

RESULTS

The measured AlloX2-Pro WET values were within 0.22 cm of RayStation predictions while metallic values ranged from 0.08 to 0.46 cm. Using natively scanned density values for the AlloX2 Pro improved the discrepancy in WET between predicted and measured from -0.22 to -0.09 cm (drain) and from -0.17 to -0.12 cm (injection). The "no-fly" zone volume of all three beams reduced 95% between the AlloX2-Pro and Dermaspan, which geometrically allowed more uniform coverage behind the port and reduced need for beam modulation.

CONCLUSION

The beam perturbation of the AlloX2-Pro is well modeled, but improved agreement with measured WET values was observed when utilizing native densities in calculations. The AlloX2 Pro can support beam arrangements that traverse the ports, which can enable simpler beam geometry and a reduction in dose modulation around the port to promote improved robustness and treatment delivery quality.

The current use of tissue expanders in breast reconstruction: device design, features, and technical considerations

INTRODUCTION

The use of tissue expanders (TE) in post-mastectomy breast reconstruction is a widely accepted practice, especially in patients desiring implant-based breast reconstruction. It has become the standard of care to perform a two-staged breast reconstruction using tissue expanders for the past 50 years due to its reliability, safety, cost-effectiveness, and versatility. Due to its popularity, there are numerous types and features of breast tissue expanders and various surgical approaches available for plastic surgeons.

AREAS COVERED

In this article, we will review the role of tissue expanders in breast reconstruction, the types and features of breast tissue expanders, and technical considerations.

EXPERT OPINION

The use of tissue expanders in breast reconstruction offers significant advantages of preserving the breast skin envelope and reestablishing the breast mound. With evolving approaches to breast reconstruction, tissue expander design, and application underwent several refinements and modifications. Due to these advances, studies on its long-term efficacy and safety profile typically fall behind and more studies with higher levels of evidence are needed to better evaluate the efficacy and safety profile of tissue expanders. With increased understanding, reconstructive surgeons can minimize complications and maximize reconstructive, aesthetic outcomes with high patient satisfaction.

The Effect of Early Cultures and Dual-port Expanders on Two-stage, Prepectoral Breast Reconstruction: The 25/25 Study

Background

Two-stage tissue expander to implant surgery remains the predominant technique for breast reconstruction. Unfortunately, there is a high incidence of reconstruction failure which portends a financial and emotional burden. Most failures are related to postmastectomy skin flap necrosis and infection. Recently, a dual-port tissue expander was introduced to the market, and the authors hypothesize that early cultures from the peri-implant fluid will guide antibiotic treatment and decrease reconstruction failure.

Methods

This is a cohort study of 50 consecutive patients treated for breast cancer or genetic susceptibility via a two-stage, prepectoral technique. The first 25 patients (46 breasts) were treated with a variety of tissue expanders, and the subsequent 25 patients (47 breasts) received a dual-port expander. Routine cultures from the drain port were taken from the dual-port group at the second postoperative visit, and cultures were taken in the control group only when signs of infection were present. All other procedures and interventions were similar.

Results

Fifty patients, totaling 93 breasts, completed the study with a mean follow-up of 145 days. There were no statistically significant demographic or pathologic differences between groups. Fifteen tissue expanders were explanted in the control group and five in the dual-port cohort (32.6% versus 10.6%, P = 0.012). All bacteria in the control group failures were either methicillin-resistant Staphylococcus aureus or Staphylococcus epidermidis, whereas failures in the dual-port group varied.

Conclusion

Treatment of routine, early cultures from a dual-port expander led to a statistically significant decrease in tissue expander explantation.

Nipple-Sparing Mastectomies in Patients over the Age of 60 Years: Factors Associated with Surgical Outcomes

BACKGROUND

Nipple-sparing mastectomy (NSM) outcomes in the elderly have not been well characterized. The goal of this study was to evaluate NSM outcomes in patients over age 60.

PATIENTS AND METHODS

A single-institution retrospective cohort study was performed for NSM patients over the age of 60 from January 2004 to January 2022. Demographic, intraoperative, and postoperative variables were collected.

RESULTS

We identified 136 women who underwent a total of 200 NSMs at a mean age 65.2 years and with mean body mass index of 25. Most (56%) had invasive breast cancer, requiring neoadjuvant chemotherapy in 15%, and 17.5% had radiation prior to NSM. A total of 91% had immediate tissue expander placement. The infection rate was 19%, with 11.5% requiring expander explantation in the follow-up period. In binomial logistic regression analysis, prior radiation increased the odds of any complication by 2.9 (OR 2.93, CI 1.30-6.58, p = 0.009) and increased the odds of infection by 5.7 (OR 5.70, CI 1.95-16.66, p = 0.001), but no associations were seen for other covariates including age, comorbidities, prior chemotherapy, or presence of invasive disease. Diabetes increased the odds of wound breakdown specifically by 9.0 (OR 8.97, CI 2.01-39.92, p = 0.004). Local recurrence was 3% in mean 3.4-year follow-up.

CONCLUSIONS

Our data support NSM in patients over the age of 60 years with acceptable outcomes within the standard of care. Locoregional recurrence was within the cited range of 0-5%, and only diabetes and prior radiation were associated with reconstructive complications. NSM should thus be offered when appropriate regardless of increased age to achieve oncologic and reconstructive goals.