6 Breast surgery

Axillary nodal status is the single most important prognostic indicator of systemic relapse in breast cancer. This is routinely assessed with a preoperative ultrasound scan and FNA analysis of any pathological nodes. Axillary lymph node dissection (ALND) remains the gold standard of managing clinically positive axillary lymph nodes or following a positive sentinel lymph node biopsy.¹

Anatomically, the axilla can be divided into three zones (Fig. 6.1):

Routine practice involves the dissection of lymph nodes up to level II, where level III clearance may be selectively carried out in the presence of extensive level II lymph node metastases.

Access to the axilla is best achieved via a 5–8cm horizontal or vertical incision. When performing a mastectomy, the axillary contents are reached via the same mastectomy wound as a continuation of the axillary tail of the breast.

Dissection involves incising the clavipectoral fascia to gain access to the axillary contents. Lateral border of pectoralis major is identified and the plane between the lateral chest wall and the axilla is created. On the posterior aspect of this space, the long thoracic nerve (nerve to serratus anterior) is identified and preserved. The dissection is continued cranially to the apex of the axilla where the axillary vein forms the superior boundary of level I nodes. Care must be taken to avoid avulsion of branches of the lateral thoracic vein from the main axillary vein trunk as troublesome bleeding will be encountered.

At this point, the thoracodorsal pedicle is identified and preserved. All axillary tissue is swept caudally off the axillary vein and laterally to the medial border of the latissimus dorsi (LD) muscle, which forms the lateral border of the axilla. Access to level III nodes can be aided by abduction and flexion of the shoulder, which relaxes the fibres of pectoralis major and minor. Where possible, axillary contents are dissected off en bloc. The intercostobrachial nerve traverses the middle of the axilla. Attempt should be made to preserve this nerve unless heavy involvement with nodal metastases may require it to be sacrificed.

Good haemostasis is ensured and routine use of a closed suction drain is common practice. Wound closure is carried out in layers using absorbable sutures.

Breast abscesses can be broadly divided into lactational and non-lactational causes. An abscess can complicate up to 10% of lactational mastitis and may affect up to 2.5% of breastfeeding mothers. The commonest cause of non-lactational breast abscess is periductal mastitis. Smoking is the strongest risk factor for this. An abscess may also arise from infective exacerbation of skin lesions (e.g. sebaceous cysts or hidradenitis suppurativa). Presentation of mastitis or a breast abscess in postmenopausal women should raise the suspicion of an inflammatory carcinoma and when tolerated, routine triple assessment should be completed.

The principal pathway of managing breast abscesses is by non-operative means. Serial ultrasound guided aspiration (± washout) of the abscess cavity is augmented with an appropriate antibiotic cover.¹ This commonly achieves a successful resolution of the abscess with superior cosmetic outcomes compared with incision and drainage. Occasionally, an ultrasound-guided insertion of a percutaneous drain may be required for large abscess cavities.

Overall, a formal incision and drainage is seldom required. For this, the core principles of ‘adequate drainage’ apply. Commonly access to the abscess cavity can be achieved through a small incision, although any overlying necrotic skin may require an excision. The cavity is washed out with copious amounts of saline and gently packed with an appropriate dressing. Use of a drain is rarely required. Wounds can be partly closed to aid healing by secondary intention. Attempt at delayed primary closure should be carefully considered as it carries a high risk of abscess recurrence. A specimen of pus or tissue from the cavity should be sent for microbiological analysis in order to direct appropriate antibiotic cover.

Indications for an incision and drainage of a breast abscess include:

Reduction mammoplasty is a common cosmetic procedure used to reduce the size and alter the shape of the breast.

The indications for a reduction mammoplasty include:

Recently, mammoplasty techniques have been amalgamated with oncological breast surgery as part of oncoplastic breast surgery. This has broadened the application of breast-conserving surgery, allowing for wide excisions of the tumour, while maintaining the optimal breast shape.

To date several different mammoplasty techniques have been described. Common to all is the reduction in breast volume that is achieved by excision of skin, fat, and glandular tissue, with subsequent repositioning of the nipple–areolar complex (NAC).

Some of the commonly utilized techniques include:

The choice of the techniques is dependent on patient as well as surgeon factors. The breast tissue is commonly excised using sharp dissection (with a knife) or with the use of diathermy. Excessive bleeding can be minimized by infiltration of breast tissue with a diluted adrenaline solution (typically 1:1000 solution). Care is required to preserve an adequate width of the dermoglandular pedicle in order to preserve nipple–areolar viability. Careful haemostasis is of paramount importance. The routine use of suction drains have not been show to alter outcomes.

Implant-based breast reconstructions are a frequently performed technique and according to recent national data, account for 37% of all immediate and 16% of delayed reconstructions following a mastectomy.¹

The key advantages of implant reconstructions are the relatively short operative time and quicker postoperative recovery. However, unlike autologous reconstructions, the cosmetic outcome can be variable and the volume and projection of the reconstructed breast can be limited. Furthermore, the effects of radiotherapy to the final aesthetic result are significant where implants have been used. The pros and cons of implant-based reconstruction need to be clearly outlined to the patient prior to surgery.

The principal consideration of an implant-based reconstruction is whether there is adequate implant cover beneath the mastectomy skin flaps. The placement of the implant in the subpectoral space (posterior to the pectoralis major) is deemed the gold standard. However, this space is limited and therefore tissue expanders are often used to create a larger submuscular space.

The access to the subpectoral space is carried out by a muscle-splitting approach along the fibres of pectoralis major or via its lateral free border with the chest wall (Fig. 6.3). Careful submuscular dissection is performed with special attention to haemostasis. Once the implant is positioned in place, muscle fibres are closed over it for complete coverage. Post-operatively, the tissue expander is gradually filled with saline over several weeks, until the desired volume is reached. A number of adjustable implants/expanders (e.g. Becker adjustable implant) allow for a single stage procedure, where the injection port can be removed once the desired volume is reached.

The standard approach is a two-staged procedure where at the second stage, adjustments the implant capsule (capsulotomy) can be made and the tissue expander is a replaced for a definitive fixed volume implant. The critical area of inadequate muscle cover is the inferior border of pectoralis major, where additional implant cover is achieved using a dermal sling as part of a Wise pattern mastectomy or an acellular dermal allograft (e.g. Alloderm). This also allows the use of fixed-volume implants in the immediate reconstruction setting and allows the implant to sit lower on the chest wall thus achieving a better natural shape.

Implants may also be used to augment an autologous reconstruction (specially an LD flap) in cases where the volume of autologous tissue available may not be adequate to achieve symmetry with the contralateral breast.

Attempts at reducing the donor site morbidity from transverse rectus abdominis myocutaneous (TRAM) flaps led to the development of muscle-sparing techniques and later the deep inferior epigastric perforator (DIEP) free flap. It was first described by Allen and Treece in 1992.¹ Today, DIEP represents the gold standard method for autologous free flap breast reconstruction, using abdominal tissue.

Potentially any woman who has had a mastectomy is candidate for DIEP flap reconstruction. Relative contraindications include a history of heavy smoking, previous long transverse or oblique abdominal incisions or where one or both deep inferior epigastric vessels have been ligated. The need for post-mastectomy radiotherapy has been shown in several series to result in an inferior cosmetic results in all reconstruction, although autologous reconstructions are deemed more resistant. There is as yet no concrete evidence to suggest radiotherapy may lead to delayed flap necrosis and thus it is not considered a contraindication.

The DIEP flap is based on the deep inferior epigastric vessels, from which two rows of arteries and veins perforate the rectus abdominis muscle on each side to supply the ipsilateral skin and subcutaneous fat. Preoperative cross-sectional imaging has been shown to help accelerate flap harvesting and to potentially identify a dominant superficial inferior epigastric systems. Preoperative markings delineate the boundaries of the breast/mastectomy cavity and the length of abdominal flap. The latter is similar to the marking of an abdominoplasty.

The abdominal flap is harvested with identification of the lateral and medial rows of the deep inferior epigastric perforators. These are then traced down to their origin, between the fibres of the rectus abdominis muscle and with full preservation of muscle function and innervation. With the vascular pedicle to the free flap isolated, it is transported to the chest and a microvascular anastomosis is fashioned to the internal mammary (and occasionally the thoracodorsal) vessels. For a bilateral reconstruction, tissue from the two halves of the abdomen needs to be harvested on separate perforator pedicles.

The flap is appropriately inset in the mastectomy cavity and the skin envelope resected to fit the mastectomy flaps. The incised anterior rectus sheath is reapproximated using a non-absorbable suture. The umbilicus is sutured in its new position and the abdominal wound closed over two suction drains.

Higher-level postoperative care is essential for regular monitoring of flap viability in the first 24–48h. Low index of suspicion should be kept for a possible haematoma and/or problems with the vascular anastomosis. Early return to theatre for an exploration is an important determinant of salvaging a threatened free flap.

Limited restriction of activity with graded physiotherapy (i.e. raising arms, lifting etc.) for at least 6 weeks postoperatively is associated with a reduction in recipient complication rates.

Complications of a DIEP flap reconstruction are divided into general, donor site, and flap-related problems

The outcome of the triple assessment for a breast lesion dictates the surgical therapy that ensues. In some circumstances, the preoperative assessment may yield inconclusive or indeterminate results thus requiring an excision biopsy to confirm the histological diagnosis. Where a lesion is preoperatively proven to be benign, decision to excise the lesion may be due to patient preference, the size of the lesion (e.g. a large (>2cm) fibroadenoma) or suspicious clinical features. Both approaches involve an excision of the target lesion with minimal disruption of surrounding normal breast tissue.

Current guidelines of the Association of Breast Surgery recommend that a preoperative diagnosis is achieved in over 90% of cases and that excision biopsy is confined to no greater than 25g of tissue.¹ Small impalpable lesions may need to be preoperatively localized using ultrasound marking and/or wire-guided techniques.

Nipple discharge accounts for approximately 5% of breast clinic referrals, of which 5% may be caused by underlying in situ or malignant disease. Nipple discharge may be coloured, from a single or multiple ducts. Serosangiunous/bloody discharge from a single duct may be associated with a papilloma, ductal hyperplasia, or carcinoma. More commonly the discharge is found to be physiological and associated with underlying duct ectasia.

The assessment of nipple discharge aims to differentiate between benign physiological discharge and ductal pathology. The principal mode of investigation remains the ‘triple assessment’. This is augmented by a number of non-surgical techniques that include ductoscopy, ductography, and ductal lavage, but these are seldom used in routine practice. The surgical management of nipple discharge can be diagnostic as well as therapeutic. The two main approaches include microdochectomy (the approach for a single duct discharge) or major duct excision.

Due to the abundance of ductal flora, antibiotic prophylaxis is often used. There is no evidence to support the routine use of antibiotic therapy postoperatively.

The approach to the mammary ducts can be achieved either via a radial incision or more commonly using a circumareolar incision (typically three-fifths to half of the areolar circumference). In a microdochectomy, it is important to express the duct discharge in theatre in order to identify the offending duct. The duct is then isolated using a lacrimal probe or via injection of methylene blue into the duct.

Ductoscopy can also be used to illuminate the relevant duct. A 2–3cm length of the duct is isolated and excised. Care should be taken to prevent excision/damage to the neighbouring normal ducts.

In a total duct excision (Hadfield's procedure), all ducts are excised from the underside of the nipple. The specimen includes the surrounding breast tissue to a depth of approximately 2cm behind the NAC (Fig. 6.4). A purse-string dermal suture behind the nipple can be used to minimize nipple inversion. Incisions are closed in layers using absorbable suture.

The LD myocutaneous flap (Fig. 6.5) was first described by Tansini in 1896. Over the years it has become a popular and versatile option for covering a large mastectomy defect, either as an autologous reconstruction or with the use of implant to augment its volume. The flap is based on the thoracodorsal vessels that enter the muscle just below its insertion into the humoral head.

Preoperative markings include that of the boundaries of the breast/mastectomy cavity and the skin paddle of the LD flap on the back. The orientation of the skin paddle is largely dependent on the patients shape and may be horizontal (along the bra straps) or oblique (using natural skin folds).

The LD flap is harvested with the patient position in the lateral position. The marked skin paddle is incised and the skin and superficial fascia is dissected off the proximal and distal boundaries of the muscle. The anterior edge of the LD muscle is identified and dissected off the chest wall. The muscle is detached from its distal attachment above the iliac crest and posteriorly from the paravertebral muscles.

The thoracolumbar fascia is left intact as incising it may increase donor site morbidity and the risk of a lumbar herniation. Dissection of the hilum of the muscle involves careful preservation of vascular braches of the pedicle to serratus anterior and more importantly the main thoracodorsal pedicle. Anterior mobility of the flap is achieved by dividing the synsarcosis between the LD muscle and teres major and/or division of the tendinous insertion of LD. Routine division of the thoracodorsal nerve at this point is recommended by some to prevent problems with flap animation. A subcutaneous tunnel is created as high up as possible in the axilla to transmit the flap into the mastectomy cavity.

The donor site is closed in layers over suction drains. The flap is appropriately inset, the skin paddle trimmed and sutured to the mastectomy flaps. In an implant-augmented reconstruction, the LD muscle provides total muscle coverage of the implant. An extended LD reconstruction is a variation that aims to provide a larger volume of tissue for a complete autologous reconstruction.¹ This approach harvests a greater degree of subfascial fat but also recruits serratus, scapular, and iliac fat pads to gain additional autologous volume.

Postoperative care involves careful observation for flap viability in the first 24–48h, good level of hydration and oxygenation and gradual mobilization of the patient.

Complication can be divided into donor site and flap-related problems:

Mastectomy is the removal of all breast tissue and some overlying skin including the NAC (Fig. 6.6). Historically, Halstedian theory dictated that breast cancer is a locoregional disease and therefore surgery would include a radical excision of all breast tissue and locoregional axillary nodes, as well as the underlying chest wall musculature (pectoralis major and minor).

More recently Fisherian theory of breast cancer has changed the paradigm of treatment from a locoregional disease to that of systemic control. For this locoregional control would again take the shape of excising breast tissue and relevant regional lymph nodes, while maintaining the integrity of the underlying structures posterior to the mammary gland.

Indications for mastectomy:

Modern-day practice encompasses the following mastectomy techniques:

The sentinel lymph node is defined as the first node that directly drains the primary tumour. Evidence to date has shown that up to 85% of all stage breast cancers to be node negative, thus patients undergoing an unnecessary axillary clearance. Furthermore, routine ALND carries significant morbidity with no impact on survival. Sentinel lymph node biopsy (SLNB) is an alternative, minimally invasive approach to ALDN that has become the standard of care in prognosticating early, clinically node- negative breast cancer.

The results of the ALMANC trial have so far shown overall lower morbidity and a shorter hospital stay in patient undergoing SLNB compared with ALND.¹

Currently, the only absolute contraindications to SLNB are clinically node-positive disease and the presence of previous mastectomy (without axillary surgery). The standard of care for patients with a positive sentinel lymph node (tumour focus of >0.2mm) is to undergo an axillary clearance or axillary radiotherapy. The oncological implications of isolated tumour cells (tumour focus <0.2mm) is currently unknown and therefore such patients are treated as SLNB negative and require no further surgery.

Recently, there has been growing interest in techniques for intraoperative analysis of sentinel lymph nodes. Such approach has been shown to avoid repeat surgery, improve patient satisfaction and reduce delays to adjuvant treatment. The techniques used include frozen section analysis and more recently, molecular techniques such as reverse transcriptase polymerase chain reaction (RT-PCR).

Current NICE guidelines recommend that SLNB is carried out by a team that is validated in the use of the technique as identified by the NEW START programme.^2,3 This programme has standardized the protocol for sentinel node mapping. It involves dual localization of the sentinel lymph node(s) using technetium-99 labelled nanocolloid and Paten V blue dye.

Access to the axilla can be incorporated into the WLE scar or via a small (commonly <5cm) de novo incision in the axilla. Minimal disruption of the axillary contents is the key. Using a handheld G-probe, any hot (measured G-radiation count >x10 background) and/or blue node is excised for histological (or intraoperative) analysis. Meticulous haemostasis is mandatory. The routine use of a suction drain is not indicated. Closure of the wound in layers follows standard practice.

The TRAM flap is an axial pattern pedicle flap popularized following its first description by Hartrampf in 1982.¹ It utilizes a paddle of skin and underlying rectus abdominis muscle, which is mobilized on its pedicle, the deep superior epigastric vessels.

However, it carries two main disadvantages. First, harvesting of significant amounts of rectus sheath and rectus abdominis muscle results in loss of abdominal wall integrity and potential for development of a hernia. The second is the relative unpredictability of the blood supply of any skin harvested beyond the muscle boundary.

Nonetheless, it provides ample tissue for autologous reconstruction of a breast, negating the need for augmentation with an implant. Modifications of this technique include muscle-sparing and the free TRAM flaps, the former resulting in lower risk donor site morbidity related to the abdominal wall. The current practice of using DIEP free flaps has become the gold standard of autologous breast reconstruction using abdominal tissue, and TRAM flaps are seldom used.

The TRAM flap (Fig. 6.7) can be used in both the immediate and delayed reconstruction setting. The preoperative skin marking on the abdomen involves a symmetrical abdominal skin ellipse similar to that of an abdominoplasty, within which the skin paddle of the flap is delineated. The myocutaneous flap on the one side of the abdomen provides autologous tissue for the contralateral breast reconstruction.

Careful dissection of skin and dermis preserves the midline-perforating vessels above and below the umbilicus, as well as the subdermal plexus that ensures maximal viability of the skin paddle. Inferiorly, the belly of rectus abdominis is isolated and transected, with ligation of the inferior epigastric vessels. Superiorly the anterior rectus sheath is divided and the muscle and the overlaying fat and skin are elevated. A subcutaneous tunnel from the abdominal wound to the mastectomy cavity transmits the flap, which is then appropriately inset and sutured to the mastectomy skin flaps.

The donor site defect is closed by approximating the anterior rectus sheet superiorly with non-absorbable suture (e.g. no 1. nylon). The defect in the inferior part of the rectus sheath is repaired with a tension free mesh closure. Transposition of the umbilicus on its stalk to its new position concludes closure of the superficial abdominal wound layers. Use of a closed suction drain in the abdominal wound is routine practice.

These can be divided into flap related or donor site related complications:

Wide local excision is a term that is synonymous with breast-conserving surgery (BCS), whereby an oncological resection is performed while maintaining as normal a breast shape (Fig. 6.8). There are no national guidelines regarding the thickness of resection of margins and locally agreed protocols are followed. Generally, the aim is to achieve macroscopic resection margins of at least 1cm and microscopic resection margins of 1mm and 2mm for invasive and in situ carcinoma, respectively. Evidence to date supports the fact that overall local recurrence and survival rates in BCS with postoperative radiotherapy are comparable with that of mastectomy alone.

The principal determinant of a satisfactory cosmetic outcome following a WLE is the proportion of breast tissue that is excised in relation to the total breast size. A resection of greater than 20% of the breast volume significantly impacts the aesthetic outcomes. Therefore recently, a number of plastic surgical techniques have been amalgamated with the oncological breast surgery, with the aim to widen the spectrum of applicability of BCS. These approaches are collectively termed ‘oncoplastic breast surgery’ and use a myriad of volume displacement, volume replacement and mammoplasty techniques to achieve the optimal aesthetic outcome while avoiding a mastectomy.

Contraindications to a WLE (or BCS) include multicentricity (presence of cancer in more than one quadrant), a high tumour to breast volume ratio (relative contraindication), and inflammatory carcinoma.

Small, impalpable lesions may require preoperative localization (e.g. ultrasound marking or wire-guided localization). An appropriately placed incision is a key principle in oncoplastic surgery. This minimizes poor cosmetic outcomes and allows for maximum access to the lesion. The full thickness resection aims to achieve macroscopically clear radial margins, and anterior (skin) and posterior (chest wall) margins may be considered less important as postoperative radiotherapy is planned.

Although a number of surgeons would leave the cavity unfilled, this almost always results in poor cosmetic outcomes especially after radiotherapy. Use of oncoplastic techniques with volume displacement techniques helps to obliterate this potential cavity.¹ Where a long subcutaneous tunnel to the lesion is created or where oncoplastic techniques are use to fill the excision cavity, use of titanium clips (e.g. Ligaclips™) help in directing radiotherapy planning.

Careful haemostasis is mandatory. Use of closed suction drains is sometimes required, especially to drain large areas of subcutaneous undermining. The wound is closed in layers using absorbable suture.