Update in Direct-to-Implant Breast Reconstruction

Abstract

Implant-based reconstruction (IBR) remains the most commonly utilized breast reconstruction option for post-mastectomy patients. IBR can be approached as either a one-stage reconstruction or a two-stage reconstruction. Facilitated by improvements in surgical technology and advanced techniques, one-stage reconstruction, also known as direct-to-implant (DTI) reconstruction, involves the insertion of an implant at the time of mastectomy. The decision to pursue either a DTI or a two-stage reconstruction is based on several factors, including the patient's overall health, expected risk of postoperative complications, and associated costs to both the patient and hospital.

The overall rate of women who undergo breast reconstructions after mastectomies has been increasing year after year, and implant-based breast reconstruction (IBR) still remains the most common reconstructive approach. ^{1 2 3} Immediate breast reconstruction following mastectomy is often the preferred approach over delayed reconstruction. According to the American Society of Plastic Surgeons (ASPS) annual report, there were a total of 109,000 breast reconstruction cases in 2016, of which 79,019 cases (72.5%) were two-stage tissue expander-based reconstruction and 9,587 cases (8.8%) were single-stage direct-to-implant (DTI) breast reconstruction. ⁴ Tissue-expansion is an immediate two-stage reconstruction initiated by the placement of an expander at the time of mastectomy. The expansion process requires at least a month of expander inflation and multiple office visits. Furthermore, this approach commits the patient to a second surgery in order to exchange the expander for a permanent implant, thus increasing potential surgical morbidity. Due to such limitations, there is a need for improvements and alternative approaches in the field of immediate breast reconstruction.

The concept of immediate single-stage breast reconstruction was first reintroduced in 2006 by Salzberg et al and was called DTI reconstruction. ⁵ DTI breast reconstruction offers an ideal reconstructive choice among select patients by restoring the breast in a single operation following either therapeutic or prophylactic mastectomy. ⁶ This approach was abandoned decades ago due to feared postoperative complications such as pectoralis muscle retraction and capsular contracture. ⁶ However, advancements in technology, such as acellular dermal matrix (ADM) and prosthetic devices, improved mastectomy techniques like nipple-sparing mastectomy (NSM); greater clinical experience has encouraged plastic surgeons to perform single-stage immediate breast reconstruction. ^{7 8 9 10 11 12} Furthermore, new imaging technology, such as intraoperative indocyanine green (ICG) angiography, has helped decrease and prevent complications by allowing assessment of the mastectomy flap and NAC blood flow in real time. ^{13 14} The advent of such oncologically safe mastectomies and improved cosmetic achieved by these techniques have improved the aesthetic quality of breast reconstruction. DTI breast reconstruction has become a reliable and safe option for certain patients, and it is a viable alternative to the traditional two-staged reconstruction. ^{7 15}

This article offers an updated review on DTI breast reconstruction by discussing indications, patient selection, preoperative planning, surgical considerations, as well as postoperative complications.

Indication and Patient Selection

Patient expectations and overall health should be assessed at the initial consultation. Healthy, nonsmoking patients with small- to moderate-sized breasts who desire to be of similar breast size following reconstruction are the ideal candidates for DTI ( Fig. 1 ). However, patients who wish to attain significantly larger breast size are better off with a two-stage tissue expander-implant reconstruction. Patients undergoing DTI reconstruction should harbor realistic expectations about their range of postoperative breast size and understand that significant breast enlargement is not possible. ¹⁶

Fig. 1.

( A–C ) Healthy, nonsmoking patients with small- to moderate-sized, minimally ptotic breasts who desire to be of similar breast size following reconstruction are the ideal candidates for DTI.

Patients with prior breast radiation or preexisting scars that adversely affect mastectomy skin flap perfusion are not considered good candidates for DTI. Similarly, patients with morbid obesity, uncontrolled diabetes mellitus, poorly perfused or thin mastectomy skin flaps, or advanced oncologic disease should be offered a two-stage approach instead. ¹⁶ On the other hand, DTI may be most advantageous for older or morbid patients who cannot tolerate additional procedures, do not desire a multiple-stage surgery, or for whom multiple surgeries would be medically unwise. ¹⁷

A special consideration must be made for patients who desire a significant reduction in breast size. ¹⁸ A nipple-sparing approach is not recommended in these patients due to technical difficulties, wound healing concerns, and the compromised viability of the nipple–areolar complex in the setting of a skin-reducing pattern or inverted-T incision. ^{10 19 20} Skin pattern reduction, either vertical or Wise patterned, can be performed in certain patients. In addition, free nipple grafting can be offered in carefully selected patients with good outcome, but is subject to high risk of nipple loss. ^{21 22}

Preoperative Planning

Patient Evaluation

A comprehensive evaluation of the patient's health and risk factors must be performed. Variables that require to be carefully considered include a patient's age, body mass index (BMI), past medical history (e.g., smoking, hypertension, diabetes mellitus), past surgical history (e.g., biopsy, prior partial mastectomy, previous breast augmentation), extent of the tumor, axillary node involvement, mastectomy weight, and desired breast size. Current medications must be evaluated for drugs with increased risks of wound healing disturbances or bleeding complications. Physical examination should focus on evaluation of breast size, ptosis, symmetry, previous scars, skin changes, nipple–areolar complex position, and chest wall configuration. In addition, a patient's breast cancer treatment plan and anticipated mastectomy type must be considered by the surgeon prior to offering DTI reconstruction.

Implant Selection

In addition to expected mastectomy weight and desired postoperative size, proper assessment of all breast dimensions is vital. The placement of an implant with insufficient width can result in concave lateral chest wall contour deformity. ¹⁶ To avoid such deformity, an implant base width that complements the chest diameter should be selected. ¹⁶ For this reason, it is advisable to have a variety of sizers readily available for proper volume selection. ¹⁶ Moreover, a three-dimensional volumetric computer program can be helpful when estimating appropriate implant size during the consultation. ²³

Tall, shaped implants are preferred by women whose breasts are positioned lower on the chest wall. Placing a regular implant in such patients can result in concave deformity in the upper pole which frequently requires fat grafting. ²³

Mastectomy Incision Type

When oncologic safety allows, NSM is preferred. Nipple–areola complex preservation positively impacts the patient's quality of life and helps them in achieving a better psychological and sexual well-being, as well as higher satisfaction with regard to their reconstruction. ^{24 25} The first choice and most favorable NSM incision is the lateral inframammary fold (IMF), as it permits good visualization for the mastectomy and is the least noticeable on frontal view. ²³ While large breasts pose a challenge for the oncologic surgeon, this incision has been associated with the lowest rate of nipple necrosis in the literature. ²⁶

The second and third choices are typically the vertical areolar to IMF incision and the inverted-T incision. Due to challenges in accessing the axilla through the vertical incision, a second incision is sometimes required. ²³ The lateral radial incision is the least favored of the incisions. It is directly visible on the breast and can cause retraction ischemia in the mastectomy skin flaps. ²³

Intraoperative Planning

Decision-making in the operating room should focus on optimizing surgical and aesthetic outcomes as well as maintaining skin viability. ¹⁶ The final decision on DTI is mostly made intraoperatively, depending on the perfusion of the mastectomy skin flap. ⁶ The surgeon may even consider participating in the mastectomy procedure to assure careful handling of the skin and avoidance of tissue retraction. Avoiding traction minimizes the stretching and distortion of the flap and decreases the risk of ischemic injury. ¹⁶ Should there be any doubt regarding the intraoperative viability of the skin flap, the procedure should be modified and an expander placed in the subpectoral pocket. The expander can then be injected with a volume sufficient to gently fill the skin envelope (hand-in-glove fit) without causing skin tension. Complete filling of the expander can be performed once the skin has healed.

Recent technological advances have allowed surgeons to assess tissue viability intraoperatively and provide actionable, objective data that augments clinical assessment. ICG fluorescence imaging was developed in the 1960s as a means of evaluating perfusion. ^{13 14 27 28} This technology provides real-time, correlative assessment of tissue perfusion both intraoperatively and postoperatively, along with the feasibility to be used multiple times during the same operative procedure. ¹⁶

Several methods have been introduced to extend the submuscular plane and support the implant in anatomic position. ^{29 30 31} Allogenic dermal grafts, such as AlloDerm (LifeCell Corp.) or DermaMatrix (Synthes, Inc.), are commonly sutured to the detached part of the pectoralis muscle and inserted at the IMF to lengthen the submuscular space inferiorly. This creates an adequately large space to place a fully inflated implant and supplement the muscle deficit at the lower breast pole. ^{31 32 33}

Complications

Each reconstructive approach carries its own inherent risks of adverse events. Both DIT and two-stage reconstruction suffer from similar complications; however, the rates at which some of these complications occur differ between the two procedures. In 2018, data was gathered from the prospective multicenter Mastectomy Reconstruction Outcomes Consortium Study and an analysis was performed by comparing patient outcomes of DTI versus two-stage tissue expander/implant reconstruction. ¹⁵ Of 1,427 eligible patients, 99 underwent DTI reconstruction and 1,328 underwent tissue expander/implant reconstruction. While complication rates were generally higher with respect to DTI reconstruction, compared with tissue expander/implant reconstruction, the differences were not statistically significant. The DTI and two-staged reconstruction complication rates were as follows: overall complication rate (32.3 versus 26.2% respectively), major complications requiring readmission or reoperations (25.3 versus 19.15%), major infections requiring intravenous antibiotics and/or implant explantation (16.2 versus 10.5%), and reconstructive failures (8.1 versus 7.4%). ¹⁵

Several other complications have been reported in the higher rates of DTI when compared with two-staged reconstruction, including nipple necrosis (4.5 and 4.1% respectively) and implant exposure (7.2 and 1.7% respectively). ^{17 34 35} In addition, reported DTI complications include flap necrosis (3.4–20.5%), seroma (1%), hematoma (0.6%), capsular contracture (0.2%), skin thinning, wound healing delay, rippling, and implant malrotation. ^{16 17} Reoperation rates were reported between 5.8 and 11.5%. ^{16 17} The risk of nipple necrosis varies significantly according to the type of mastectomy incision. Periareolar and circumareolar NSM incisions were associated with the highest rates of nipple necrosis (17.81%). ²⁶

Revision, Postoperative Care and Prevention of the Complications

All empty spaces must be drained to prevent seroma and limit stress on the skin envelope in the postoperative period. Drains are removed when output is less than 30 ml for 48 hours. Patients are typically maintained on oral antibiotics until the drains are removed.

Ischemic injury to the skin envelope may occur during the mastectomy if skin flaps are too thin or under excessive tension. Typically, ischemic injury presents as exposed dermis and/or a red or blue discoloration to the skin either immediately after the mastectomy or inflation of the sizer. Significant intraoperative ischemic injury warrants a two-stage approach or delayed breast reconstruction. Ischemic injury can also occur during the reconstructive phase, as placement of the implant exerts tension on the skin flaps. If skin necrosis develops postoperatively, aggressive management is necessary. Mild skin necrosis involving 2 to 5 mm of skin edges can often be managed with debridement and closure under local anesthesia. In addition to extensive skin debridement, cases of severe necrosis necessitate downsizing the implant or exchanging it with a tissue expander. ³⁶

Seroma can be managed with percutaneous drainage in the outpatient setting. Acute hematomas must be explored, whereas subacute hematomas can be drained. Minor infections can be treated on an outpatient basis with oral antibiotics. Patients with major infection should be admitted and receive intravenous antibiotics; if the infection is persistent, patients should undergo removal of the implant. Baker grade 3 or 4 capsular contracture is classified as a late complication and requires periprosthetic capsulectomy and/or capsulotomy. ⁷

Cost Evaluation

Direct-to-implant reconstructions have been associated with a higher risk of adverse events and reoperations, all of which increases the overall cost. ⁷ On the other hand, a recent study from Boston-authored de Blacam et al demonstrated that immediate single-stage implant breast reconstruction using ADM reduces the total number of postoperative clinic visits and the need for a second procedure, both of which effectively reduced the overall cost. ³⁷

A comprehensive literature review of studies that directly compared single-stage against two-staged expander-implant breast reconstruction in a matched patients' cohort was conducted by Krishnan et al to identify the most clinically relevant associated complications, costs, and utilities. ⁷ Probabilities of clinically relevant complications were combined with cost and utility estimates for a decision tree analysis. Single-stage reconstruction with ADM and silicone implant proved to be the least costly approach, while deep inferior epigastric perforator flap reconstruction was the most expensive. ^{6 38} Furthermore, single-stage reconstruction with silicone implant and ADM was less expensive than two-staged implant reconstruction in both unilateral and bilateral cases. ⁷

Two-staged tissue expander-implant reconstruction comprised the highest procedure volume and accounted for the greatest share of total cost. ⁷ Recognizing these cost trends is crucial, so that efforts, such as moving toward single-stage procedures in select patients or reducing the direct costs of implants and ADM, can be made to reduce such expenses.

Discussion

Although several options are currently available for reconstructing the breast after mastectomy, implant-based techniques remain the most common. ³⁹ DTI reconstruction has become a favorable option for both patients and surgeons as it offers distinct advantages. A single-stage combined mastectomy–reconstruction approach eliminates the need for multiple tissue expansion visits, a second implant exchange operation, and the possibility of a prolonged expansion period influenced by postoperative complications or adjuvant cancer therapies.

Patient selection plays a major role when it comes to deciding between DIT and two-stage reconstruction. ⁴⁰ Patients with small, minimally ptotic breasts are the most ideal candidates for DIT, whereas patients with larger, more ptotic breasts are counseled for a two-stage approach and a contralateral procedure for symmetry. Irradiated patients are considered less than ideal for implant-based breast reconstruction due to higher capsular contracture rates and the risk of implant extrusion from severe radiodermitis. ⁴¹

Direct-to-implant reconstruction is generally preferred for prophylactic and risk-reducing mastectomies, especially in small and non-ptotic breasts. On the other hand, the two-stage approach allows for a good quality breast reconstruction using anatomically shaped expanders and implants in almost every type of patient, particularly among those requiring adjuvant treatment, a potential cause of breast asymmetry. In addition, contralateral breast surgery has been shown to improve patient satisfaction and aesthetic outcomes, particularly in young patients. ^{41 42 43} The matching procedure ranges from a simple augmentation or mastopexy to a breast reduction. ⁴¹

Although the number of patients requesting DTI reconstruction is increasing, many surgeons may be hesitant to perform the procedure due to a perceived higher risk of complications when compared with traditional expander-implant techniques. While many studies have shown higher complications rates in DTI reconstruction, the majority were part of a retrospective single-institution design with an inherent risk of bias. ^{16 17 26 34 35} The 2018 multicenter prospective study successfully controlled for such limitations and demonstrated no significant difference in patient-reported outcomes between the two approaches. ¹⁵ Surgeons should be encouraged to consider single-stage reconstruction in properly selected patients when feasible. ⁷ Patients undergoing single-stage reconstruction should have realistic expectations and understand that significant breast enlargement is unlikely. ³⁰ Patients who smoke or have poorly controlled diabetes mellitus, prior breast irradiation, or very thin mastectomy skin flaps should be carefully assessed prior to offering single-stage breast reconstruction, and should be counseled to undergo two-stage reconstruction, whether immediate or delayed. ³⁰

It is crucial that the plastic surgery, breast surgery, and oncologic teams coordinate their services and work together for optimal patient care and final outcomes. Synergy between teams can also contribute to cost-effectiveness, as it reduces the number of hospitalizations, the surgical cost, and the additional costs of the expander. ³⁰ Breast reconstruction with a definitive anatomical silicone filled implant after skin-sparing mastectomy and NSM can produce excellent cosmetic results in one surgical stage with a low rate of complications ( Fig. 2 ). ³⁰ Surgeons and patients must weigh the psychological benefits, aesthetic outcome, and overall time and potential cost savings against the potentially greater complications and risks of single-stage reconstruction.

Fig. 2.

( A–C ) Bilateral direct-to-implant breast reconstruction following right therapeutic skin sparing mastectomy and contralateral matching procedure.

Conclusion

Breast reconstruction approaches are always evolving with new trends continuously emerging. With recent technological advances and oncologically safe and improved mastectomy techniques, more patients are undergoing risk-reducing mastectomies and opting for a single-stage reconstruction. Given the inherent advantages of DTI reconstruction, risks, and patient-reported outcomes when compared with the traditional two-staged expander/implant procedures, DTI procedures may be worth considering in select patients.