A Guide to Prepectoral Breast Reconstruction: A New Dimension to Implant-based Breast Reconstruction

The use of meshes and matrices in breast reconstruction

Breast cancer is the most common cancer diagnosed in the UK ( Cancer Research UK, 2018 ). Breast reconstruction following mastectomy can be performed with prosthetic devices or autologous tissue. In the UK implant-based breast reconstruction following mastectomy is the most common type of breast reconstruction, estimated to account for 70% of the reconstructive caseload in the UK. Since 2001 there has been a considerable increase in the number of prosthetic reconstructions performed with the use of mesh or matrix to augment the reconstructive pocket. This article introduces the main types of mesh and matrix used in implant-based breast reconstruction, reconstructive techniques and reviews the benefits and complications associated with their use.

Tissue Contraction-A New Paradigm in Breast Reconstruction

Supplemental Digital Content is available in the text.

Background:

Skin expansion is commonly needed in order to reconstruct the breast following modified radical mastectomy. With the advent of skin-sparing and nipple-sparing techniques, expansion is no longer necessary. The natural ability of healing tissues to contract can be advantageously used to improve the outcomes of immediate prepectoral breast reconstruction.

Methods:

A prospective analysis of the results of 20 prepectoral breast reconstructions following skin-sparing or nipple-sparing mastectomies was performed. Reconstruction was performed using the adjustable breast implant initially underfilled with air. No acellular dermal matrix or mesh support was used. Further air was added during the follow-up office visits. Air was replaced with normal saline when the desired breast size was achieved. The adjustable implants were replaced with silicone gel implants when necessary.

Results:

Contraction of the skin flap over the underfilled implant was noticed in all patients. Five patients (25%) developed a seroma, and 2 patients had hematoma of the breast pocket. Wound-edge necrosis required debridement in 2 patients (10%). Complications were all resolved without implant loss.

Conclusions:

Tissue contraction can be successfully utilized in breast reconstruction following skin-sparing and nipple-sparing mastectomy. Contraction results in thickening and elevation of the flap, eliminating the need for skin excision or the use of acellular dermal matrix. The partially filled implant functions as a spacer, preventing the flap from adhering to the underlying muscle and avoiding pressure on the skin flap.

Impact of Postmastectomy Radiation Therapy in Prepectoral Versus Subpectoral Implant-Based Breast Reconstruction

BACKGROUND

This study aimed to compare the impact of postmastectomy radiation therapy (PMRT) on outcomes after prepectoral versus subpectoral implant-based breast reconstruction with local deepithelialized dermal flap and acellular dermal matrix (ADM).

METHODS

From 2010 to 2017, 274 patients (426 breasts) underwent prepectoral reconstruction. In this group, 241 patients (370 breasts) were not exposed to PMRT, whereas 45 patients (56 breasts) were exposed to PMRT. Of 100 patients (163 breasts) who underwent partial subpectoral reconstruction, 87 (140 breasts) were not exposed to PMRT, whereas 21 patients (23 breasts) were exposed. The outcomes were assessed by comparing complication rates between the pre- and subpectoral groups.

RESULTS

A higher rate of capsular contracture was found for the prepectoral patients with PMRT than for those without PMRT (16.1 vs 3.5%; p = 0.0008) and for the subpectoral patients with PMRT than for those without PMRT (52.2 vs 2.9%; p = 0.0001). The contracture rate was three times higher for the subpectoral patients with PMRT than for the prepectoral patients with PMRT (52.2 vs 16.1%; p = 0.0018). In addition, 10 (83.3%) of 12 cases with capsular contracture in the subpectoral cohort that received PMRT were Baker grades 3 or 4 compared with only 2 (22.2%) of 9 cases of the prepectoral group with PMRT (p = 0.0092).

CONCLUSIONS

The patients undergoing subpectoral breast reconstruction who received PMRT had a capsular contracture rate three times greater with more severe contractures (Baker grade 3 or 4) than the patients receiving PMRT who underwent prepectoral breast reconstruction.

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.

Important Considerations for Performing Prepectoral Breast Reconstruction

Prepectoral breast reconstruction has emerged as an excellent technique for postmastectomy reconstruction, as it allows for full preservation of a patient's pectoralis major muscle and chest wall function. This reduces pain, eliminates animation deformity, and results in high patient satisfaction. Safely performed prepectoral breast reconstruction requires a careful patient selection process before committing to the procedure, taking into account comorbidities, radiation status, and oncologic criteria such as tumor location and breast cancer stage. Furthermore, a thorough intraoperative assessment of mastectomy skin flaps is critical, with careful and precise confirmation that the skin is viable and well perfused, prior to proceeding with prepectoral breast reconstruction. This can be done both clinically and with perfusion assessment devices. The use of acellular dermal matrix (ADM) has enhanced outcomes and aesthetics of prepectoral reconstruction, by providing implant coverage and soft-tissue support. The ADM also adds the benefit of reducing capsular contracture rates and offers full control over the aesthetic definition of the newly reconstructed breast pocket. Aesthetic enhancement of results requires routine use of oversizing implants in the skin envelope, careful selection of full capacity or cohesive gel implants, and autologous fat grafting. In this way, patients in all clinical scenarios can benefit from the full muscle-sparing technique of prepectoral breast reconstruction, including those undergoing immediate reconstruction, delayed reconstruction, and delayed conversion from a subpectoral to prepectoral plane to correct animation deformity.

The Economics of Prepectoral Breast Reconstruction

The world of breast reconstruction over the last several years has seen a dramatic shift in focus to discussion and the application of placing tissue expanders and implants back into the prepectoral space. Although this technique failed during the early advent of breast reconstruction, newer technologies such as advances in fat grafting, improved acellular dermal matrices, better methods of assessing breast flap viability, and enhanced implants appear to have set the stage for the resurgence and positive early results seen with this technique. The main benefits of a switch to prepectoral breast reconstruction clinically appears to be less associated pain, lower incidence of animation deformities, and its associated symptoms as well as presumably better aesthetics. Early data suggest that the results are extremely promising and early adopters have attempted to define the ideal patients for prepectoral breast reconstruction. As with any new operative procedure, an assessment of finances and costs are crucial to its successful implementation. Although current data are minimal, this article attempts to build the fundamentals of an economic model that exhibits and displays potential savings through the use of prepectoral breast reconstruction.

Prepectoral Breast Reconstruction

Oncologic and reconstructive advancements in the management of patients with breast cancer and at high risk for breast cancer have led to improved outcomes and decreased patient morbidity. Traditional methods for prosthetic breast reconstructions have utilized total or partial muscle coverage of prosthetic devices. Although effective, placement of devices under the pectoralis major muscle can be associated with increased pain due to muscle spasm and animation deformities. Prepectoral prosthetic breast reconstruction has gained popularity in the plastic surgery community, and long-term outcomes have become available. This article will review the indications, technique, and current literature surrounding prepectoral prosthetic breast reconstruction.

Radiologic-Pathologic Correlation: Acellular Dermal Matrix (Alloderm®) Used in Breast Reconstructive Surgery

Acellular dermal matrix (ADM) such as Alloderm^® is sometimes used in tissue reconstruction in primary and reconstructive breast surgeries. As ADM is incorporated into the native tissues, the evolving imaging findings that would correlate with varying degrees of host migration and neoangiogenesis into the matrix can be challenging to recognize. In the setting of a palpable or clinical area of concern after breast reconstructive surgery following breast cancer, confident diagnosis of a mass representing ADM rather than recurring or developing disease can be challenging. Such diagnostic imaging uncertainties generally result in short-term imaging and clinical follow-up, but occasionally, biopsy is performed for histopathological confirmation of benignity. A case of biopsy-proven Alloderm^® is described. To the best of our knowledge, this is the first radiologic-pathologic correlation of ADM in the literature.

Subcutaneous implant breast reconstruction: Time to reconsider?

Improvements in breast surgery techniques such as skin and nipple preserving mastectomy and innovative prosthetics (implants, acellular dermal matrices and meshes) is renewing interest in subcutaneous (pre-pectoral) implant reconstruction. The aim of this paper is to review the current literature in an attempt to provide a rationale that may support a return to subcutaneous implant placement, so minimising the pain and functional problems resulting from submuscular breast reconstruction.