Among breast reconstruction methods using a prosthesis, prepectoral breast reconstruction is acknowledged for its stability and cosmetic outcomes. Sigalove et al reported that prepectoral breast reconstruction is a safe method with predictable results (17). In addition, several papers have reported its excellent postoperative outcomes, such as reducing pain and animation deformity owing to the preservation of the pectoralis major (18-21).
Several previous studies have discussed prepectoral DTI breast reconstruction. The study by Reitsamer et al described the full coverage of the prosthesis using porcine ADM Strattice (LifeCell Corporation, Bridgewater, NJ, USA) (4), whereas Vidya et al reported beneficial results from a method that fully covers the prosthesis using Braxon®, a single large ADM (22). Similarly, our team reported outcomes of prepectoral DTI breast reconstruction with complete implant coverage using a double-crossed ADM (9). Most prepectoral DTI breast reconstruction using ADM described in several studies used ADM for full coverage of the implant (14-16).
Some studies have also reported the anterior coverage method, wherein only the anterior part of the implant is covered. Kyle et al introduced a technique for anterior coverage using a method to sling AlloDerm™ partially through the dual-plane technique (23). Ayesha et al and Yang et al reported methods involving complete anterior coverage of an implant (24,25), but only a few studies have discussed a method that completely covers the anterior part of the ADM (i.e., complete anterior coverage).
Our team performed prepectoral DTI breast reconstruction, in which the implant is inserted into a pocket, to achieve complete anterior coverage. This was made by fixing a single, large, square-shaped ADM to the pectoralis major. Our study aimed to determine the functional and cosmetic outcomes of our prepectoral DTI method and compare the outcomes with those of the classic subpectoral DTI technique.
We compared postoperative outcomes between patients who underwent the subpectoral technique and those who underwent the prepectoral technique. We also evaluated complication rates, patient satisfaction using the KNUH Breast-Q scale, and symmetry using the Vectra H2 3D scanner. No significant difference in major and minor (i.e., seroma, linear skin necrosis, hematoma, capsular contracture, infection, and rippling) complications was observed between the two groups. However, the mean drain removal period was 10.5429 ± 2.2274 and 8.5588 ± 2.5008 days (p < 0.001) in the subpectoral and anterior coverage groups, respectively. This implies that it takes less time to recover when using the anterior coverage technique versus the subpectoral technique. The hospitalization period is shortened, and the patient can return to daily life faster because of early discharge. Furthermore, the anterior coverage technique had noninferior stability and faster recovery time than the subpectoral technique did.
Moreover, it has been reported that the percentage of skin necrosis may be high when conducting prepectoral reconstruction along with mastectomy skin flap (1). In our study, a lower percentage of linear skin necrosis was observed in prepectoral reconstruction using the anterior coverage method versus the subpectoral method, but its statistical significance was not verified. This is thought to have an effect, as surgery was performed only for patients with an indication after confirming that the thickness of the mastectomy flap and the perfusion state were appropriate for prepectoral reconstruction. In addition, it is thought that because our surgical method covers the anterior surface of the implant after spreading the ADM wide, the relatively good adhesion between the skin flap and the ADM might also have had an effect.
One case (2.86%) of capsular contracture occurred in the subpectoral DTI group. This patient received postmastectomy radiation therapy after mastectomy and subpectoral DTI. Two patients received postmastectomy radiation therapy in the anterior coverage group, but no capsular contracture occurred in these patients (Fig. 3).
Infection occurred in one patient (2.86%) in the subpectoral patient group and in none (0%) of the patients in the anterior coverage group. Despite our compliance with the hospital’s infection prevention protocol when performing breast reconstruction through DTI (26), occasional cases of infection still occur. In these cases, our team immediately administered empirical antibiotics and referred the patient to other departments to quickly diagnose and establish a treatment plan so that proactive surgical intervention could be considered alongside appropriate drug therapy (26). In the single case with infection in this study, broad-spectrum antibiotics were administered immediately upon appearance of symptoms. Salvage reoperation was not performed, as the symptoms of infection subsided within a short time.
A previous study found that implant visibility and rippling occur frequently after breast reconstruction with prepectoral DTI (9). In this study, rippling occurred slightly more frequently in the anterior coverage group than in the subpectoral DTI group (two patients [5.71%] vs. zero patients [0%]). As a patient group for prepectoral DTI, an indication is set as a group of patients who had undergone skin-sparing or nipple-sparing mastectomy; flap quality (thickness, vascularity) should be confirmed, and it is advantageous to exclude from the indication for preoperative radiotherapy history, current smokers, and patients with uncontrollable diabetes mellitus in which the skin flap may not be in good condition (9).
We found no significant difference between the two groups in the KNUH Breast-Q scale, which evaluated subjective satisfaction with breast reconstruction and QoL after surgery. Furthermore, no significant differences were found in symmetry measurement using the Vectra H2 3D scanner. The Vectra H2 3D scanner enables the measurement of the SN–N distance, IMF–N difference, breast width, N–M distance, breast projection difference, and breast volume of patients (Fig. 2). Yan Yang et al reported measurements of breast symmetry using surface anatomy (27). Although there are some discrepancies between their surface anatomy parameters and those of our study, we did not experience difficulties measuring breast symmetry using our parameters.
According to our results, there was no statistically significant difference in symmetry measured by the 3D scanner, but a smaller difference was observed in the anterior coverage group in all items. This represents the superiority of anterior coverage in adjusting breast symmetry during breast reconstruction, which is in line with the findings of existing studies claiming that prepectoral breast reconstruction can yield superior cosmetic outcomes. The superiority in cosmetic outcome can be seen in the gross photos captured in patients with anterior coverage during their follow-up (Figs. 3 and 4).
During prepectoral DTI breast reconstruction with anterior coverage, all aspects of ADM are fixed to the pectoralis muscle. In particular, when fixing the inferior aspect of ADM, it is made to form a natural IMF by folding the ADM downward into the implant sizer (Fig. 1); this may improve cases of ptotic breasts. Compared with the prepectoral DTI technique through full wrapping, the prepectoral DTI technique with anterior coverage has an effect of reducing the dead space between the skin flap and ADM. Unlike full wrapping, wherein implants are wrapped based on the shape of the ADM, the anterior coverage technique takes into consideration the natural breast shape, and thus the ADM is spread over the implant, and the anterior surface of the implant is covered. The outcome of complications such as seroma were better with the anterior coverage method than with the full wrapping method, although these findings require verification in further studies.
Despite its prospective cohort study design, one limitation of this study is the small number of patients in both groups, which hindered statistical verification. In addition, the superiority of the anterior coverage method could have been better demonstrated by comparing it with prepectoral breast reconstruction methods other than the subpectoral method. Finally, the relatively short follow-up period in some patients is considered to be another limitation.
Regardless of these limitations, our findings demonstrate that anterior coverage–based breast reconstruction had superior outcomes over the existing subpectoral implant-based reconstruction in terms of faster recovery time and breast symmetry.