It is not important whether a general or a plastic surgeon performs the mastectomy, provided the surgeon has the appropriate training and skills to be able to safely find and then stay within the mastectomy plane.

The mastectomy plane lies between the subcutaneous fat and the superficial fascia of the breast, crossed by the ligaments of Cooper that travel through the subcutaneous fat to anchor in the dermis (Fig. 24.1a). There is a conventional view that the superficial fascial plane is not reliably present and thus the plane may not always be identifiable. This appears to be based on an often-quoted small observational study [10] of breast-reduction specimens. There is, however, a compelling embryological explanation for the constant presence of this fascia, even if patient factors (extremes of BMI) or surgical factors (poor or closed techniques) mean that it is not always visualized. The superficial fascia is formed as a condensation from the sixth embryological week, when the primary ectodermal breast bud invaginates into the underlying mesenchyme [11].

Regardless of the technique and instruments used, achieving the correct dissection plane is essential for optimal oncological safety and viability of the skin envelope. A ‘thin’ or traumatized skin flap is more likely to have compromised perfusion. A ‘thick’ skin flap is more likely to carry residual breast tissue with an unnecessary increased risk of future disease or local recurrence (Fig. 24.1b, c). There are several well-designed studies that demonstrate residual breast tissue left on mastectomy skin flaps in up to 50 % of biopsies looked at [12–14]. Without evidence of intact superficial fascia on the mastectomy specimens removed, such studies should be interpreted with caution.

It should be remembered that the ‘ideal’ skin flap thickness is proportionate to a patients BMI and body habitus and is therefore ‘patient-dependent’ not ‘surgeon-dependent’. It should be possible to aim for complete removal of the breast tissue, and breast surgeons should continue to strive for the cleanest possible dissection in the plane; i.e. over the fascia, with division of the ligaments of Cooper as close to dermal attachments as possible (Fig. 24.1d).

Planning the mastectomy must take into account the three-dimensional shape of the envelope, the likely tension on the skin and the access that the incision will give, for both the least traumatic removal of the gland and the safest, most accurate insertion of the implant.

Once the optimal amount of skin (with or without nipple) for the best envelope and reconstruction has been decided upon, the joint surgical objectives are:

There is no agreement, nor need there be, on the single best technique for performing skin sparing mastectomy. Some surgeons find infiltration helpful to develop the plane (with or without adrenaline). Alternatively a dry technique with direct visualization of the fascia and ligaments may be preferred. Scalpel, scissors, diathermy electrodissection, ultrasound, laser and argon all have their advocates. In selecting the technique for mastectomy, every surgeon must decide how best to reconcile the compromise among ease of dissection, speed, haemostasis and the development of complications such as seroma, haematoma and skin necrosis.

Finally, the appropriate selection of the technique and instruments to use for a specific mastectomy should be based not on a surgeon’s routine preference, but after consideration of that patient’s individual soft tissue characteristics and risk factors for skin necrosis (obesity, smoking status, etc.,).

When the nipple is to be sacrificed, our preference is for a short ellipse including the nipple with an oblique orientation (Fig. 24.3a). The dimensions and exact orientation of the ellipse should take into account the desired final three-dimensional shape and volume of the breast. The incision may require a short ‘lazy-S’ lateral extension, so that it is large enough to allow safe access for mastectomy, accurate insetting of the ADM and access to the axilla if necessary. Excess skin should be excised with caution and after consideration of the characteristics of the skin envelope (elasticity, compliance, possible perfusion problems) as well as how to achieve a comfortable fit between the implant domain and the skin envelope. It is always possible to modify and excise further if there is large skin excess when the envelope is redraped over the newly created mound. The oblique scar created is usually not conspicuous after nipple–areola reconstruction (Fig. 24.4).

If an ADM is to be used rather than an LPS, then our preference is for the transvertical approach (Fig. 24.3b), which combines two vectored skin excisions—the larger, horizontal one is placed lateral or oblique to the nipple–areola complex (NAC) and the shorter, vertical elliptical excision overlaps the former in the NAC area. The resultant skin envelope has a more pleasing final shape and a better positioned scar than if a longer, wider oblique or transverse ellipse is used. The transvertical approach avoids the potential ischaemia-related wound-healing problems encountered by some surgeons when using the Wise-pattern skin envelope (Figs. 24.5 and 24.6).

Traditional periareolar and circumareolar incisions have been shown in the best centres to have an increased risk of nipple–areola necrosis [15, 16]. Although it is possible to use an oblique orientated ‘lazy-S’ upper outer quadrant incision (Fig. 24.3d), our preference is for the use of an inframammary incision whenever possible (Fig. 24.3c). Although this is more technically challenging, there is less of a risk to nipple viability. The resultant access to the lower pole is ideal for the accurate insertion of the ADM and affords precise control and fixation of the IMF. It also produces a very favourable and ‘hidden’ scar (Figs. 24.7 and 24.8).

As mentioned earlier, the technique and instrumentation chosen for mastectomy through the IMF incision is less important than the surgeon’s ability to produce a healthy, non-traumatized skin envelope and a well-perfused nipple. Where access is difficult, the use of a headlight and delicate use of retractors is essential. Great care must be taken by the surgeon and assistant to avoid mechanical crush of the lower pole skin. An endoscope may be useful in the large breast (video-assisted mastectomy) for direct visualization of the medial, superior and lateral extent of the envelope, thus minimizing retraction injury or damage to the important skin perforator vessels.

Although the risk of occult nipple involvement or future nipple disease is acceptably low, provided predictive criteria for further nipple disease are followed [17, 18], we still recommend a subareolar ductal biopsy in all cases of nipple preservation with intraoperative frozen section. This requires close collaboration with an excellent histopathologist with a low false-negative rate for detecting occult disease on frozen section. Others may prefer to perform preoperative MRI, staged subareolar duct excision or subareolar vacuum-assisted biopsy prior to making a decision about the safety of nipple preservation. If the frozen section (or subsequent pathology report) demonstrates occult subareolar disease, then the nipple must be excised intraoperatively (or in a second procedure).