Improvements in breast reconstruction technique have significantly enhanced the quality of life for most patients with breast cancer. Therapeutic standards have evolved from radical intervention to skin-sparing mastectomy (SSM) or most recently nipple-sparing mastectomy (NSM), advancing reconstructive and aesthetic outcomes incrementally [12]. Although NSM has raised safety issues, this technique is generally considered an acceptable oncologic option in properly selected patients [345].

The demand for immediate breast reconstruction following conservative mastectomy has increased, with implant-based reconstruction most commonly pursued. According to Albornoz et al. [6], approximately 80% of all breast reconstructions performed in the United States involve prosthetic devices, and the vast majority are implanted immediately, placed at the time of mastectomy. When performing immediate implantbased breast reconstruction, it is still debatable whether a single-stage, direct-to-implant (DTI) strategy or a two-stage (tissue expander/implant) solution is best.

NSM with immediate prosthetic reconstruction may be performed using either a one-stage or two-stage method. Proponents of the one-stage DTI approach emphasize its low revision rate, fewer operations, reduced overall cost, and excellent patient outcomes [789]. Those supporting the two-stage method cite the opportunity to recontour and select an ideal device at second stage, reduced capsular contracture risk in the setting of postmastectomy radiation, lower unplanned revision rate, as well as excellent patient outcomes [1011].

When performing NSM, the choice of incision may be problematic, given that numerous variations have reportedly shown merit. Alternatives include radial, transverse periareolar, lateral, inferolateral, double concentric periareolar, vertical infra-areolar, and inframammary fold (IMF) incisions, with or without an axillary extension [12131415]. Endara et al. [16] have comprehensively addressed the process of choosing an appropriate incision for NSM. A radial or IMF incision is known to minimize scarring.

Although no incision is ideal, some certainly should be avoided. Endara et al. [16] found similar rates of nipple necrosis for radial and IMF incisions (8.8% and 9.1%, respectively), whereas this rate was much higher (17.8%) for periareolar/circumareolar incision lines. The highest incidence of nipple necrosis (81.8%) was recorded for a transareolar approach [16]. Using IMF incisions, the Beth Israel Deaconess group achieved an 82.0% nipple-areolar complex (NAC) survival rate in 17 breasts [17]. Blechman et al. [18] also reported a 94.0% NAC survival rate; in our series, the NAC survival rate was 95.1%.

Both oncologic and plastic surgeons would nevertheless agree on the convenience of a non-IMF incision in performing NSM. Moreover, a clearer intraoperative view is enabled. The drawback is a potential for visible scarring and nipple deformity or positional changes as likely consequences of scar contractures.

In this study, we examined two groups of patients who underwent DTI reconstruction after NSM, comparing complications encountered, revision rates, and aesthetic outcomes. The patients were stratified by the nature of the surgical incision, assigned to IMF and non-IMF groups.

Presently, NSM is a valid surgical option for treating breast cancer in selected patients. The combination of NSM and immediate breast reconstruction has been gaining traction as a preferred surgical strategy [222324], Furthermore, NSM techniques now include removal of glandular tissue from the nipple. This is a critical point of differentiation from prior subcutaneous mastectomy methods, where significant residual breast tissue was retained within and beneath the nipple. Benediktsson and Perbeck [25] have subsequently confirmed the oncologic safety of NSM, showing survival rates comparable to those of conventional mastectomy, given a 13-year median follow-up period.

One- and two-stage prosthetic reconstructions have been performed at a number of institutions using an array of incisions, including periareolar, inferior radial, inframammary, lateral, lateral radial, and inferolateral variations. The selection of a one- or two-stage approach in the setting of NSM is a complex process. Two-stage reconstruction yields better results, improving symmetry and implant position. Moreover, this strategy allows greater control over final breast volume and shape. However, cost is clearly a factor in that surgery is carried out at least twice. On the other hand, one-stage prosthetic reconstruction has few complications and confers relatively good aesthetic outcomes. At our facility, two-stage prosthetic reconstruction is elected if skin flap volume is scant or postoperative radiotherapy is anticipated.

As Endara et al. [16] have maintained, choosing the right incision for NSM facilitates both therapeutic and reconstructive efforts, preserving nipple-areola blood flow and producing an aesthetically favorable scar. Our oncologic surgeons generally relied upon non-IMF incisions until 2016. Thereafter, IMF incisions were introduced, supported by ideal incision criteria (referenced earlier). Since this transition, patient satisfaction has improved, and surgeons are pleased with the results, hoping to even further improve postoperative aesthetics.

Herein, we examined patients undergoing one-stage DTI breast reconstruction via non-IMF incisions and those reconstructed through IMF incisions, comparing complications. Skin necrosis in the IMF (n=9, 14.5%) vs. non-IMF (n=18, 21.7%) group was significantly less prevalent (p=0.030). There were nine instances of IMF-related skin necrosis in early 2016, suggesting a learning curve for this this new method. By preserving 3rd and 4th intercostal perforators to fortify the blood supply, our oncologic surgeon successfully enhanced remnant skin flap thickness and viability, and skin necrosis was seldom seen later that year. Nevertheless, skin necrosis did remain more problematic in non-IMF (vs. IMF) incisions, especially at the lower pole of the breast. One potential explanation is the gravitational pressure of implants against the lower reaches of skin flaps.

In the evolution of NSM procedures, the advantage of immediate breast reconstruction has brought to bear the importance of skin flap thickness in maintaining flap viability. Using 4 to 5 mm flaps, some sources [26] have confined necrosis to ~17%; through even thicker (10-mm) flaps, others have achieved rates <5% [2728]. Although thicker remnant flaps may indeed limit necrosis, no standard method is yet available for calibration, so consistency may be difficult to ensure. On average, our team generates 8-mm skin flaps. We are convinced that such relatively thick flaps may contribute to the lower rates of flap necrosis presently achieved. This also explains the lesser mean implant size in our IMF group, compared with the non-IMF group. The thin skin flaps formerly left behind were needed to cover larger sized implants. However, current (i.e., less aggressive) mastectomy trends leave relatively thick skin flaps, restricting the size of breast implants.

Rates of hematoma and seroma did not differ significantly by incision type, nor did the rate of capsular contractures, albeit somewhat premature. The follow-up period of ~1 year in the IMF group is possibly insufficient to reasonably assess contracture rates. Extended follow-up monitoring in future studies is truly needed. Rates of infection, implant loss, and tumor recurrence similarly showed no between-group differences.

In a subgroup analysis comparing postoperative complications in PMRT and non-PMRT groups, the various complications encountered did not differ significantly. As for reoperation outcomes, implant extraction was significantly more likely in the non-IMF (vs. IMF) group. This may be related to the higher rate of skin necrosis shown by the non-IMF group. Our data further indicated that PMRT had no impact on reoperation outcomes, regardless of incision type.

A multiplicity of criteria has been developed for assessing the aesthetic outcomes of NSM, including patient self-assessment, nipple sensitivity, postoperative scarring, nipple placement, breast contour, and overall symmetry [172930]. We used three criteria in our evaluations: NAC position, breast shape, and symmetry. IMF incisions concealed postoperative scarring and also resulted in fewer patient complaints.

Bilateral reconstruction (IMF group: four mastectomies) was excluded in our analysis of aesthetic outcome, owing to an inherent advantage in terms of symmetry. Accordingly, 35 patients (67.3%) in the IMF group were rated as having very good or good results, surpassing the corresponding rate (49.1%) in the non-IMF group. In the IMF (vs. non-IMF) group, significantly more patients were rated as very good (p=0.002).

Of note, we found no significant differences in aesthetic outcomes of IMF and non-IMF incisions after PMRT, regardless of aesthetic rating achieved. It may be that PMRT effects offset any aesthetic benefit conferred by IMF incisions. However, the aesthetic superiority of IMF (vs. non-IMF) incisions was upheld in non-PMRT subgroup analysis. Finally, because aesthetic outcomes were evaluated by our staff plastic surgeons, bias cannot be ruled out.

In conclusion, the use of IMF incisions for DTI breast reconstruction after NSM allows complete preservation of the NAC, with superior aesthetic results. We found that related postoperative complications, secondary corrective operations, and oncologic safety all compared favorably with non-IMF incisions. Moreover, IMF incisions produced the least visible scars and did not affect breast shape. Most patients expressed satisfaction with their aesthetic outcomes.