Oncoplastic procedures to allow breast conservation and a satisfactory cosmetic outcome

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Oncoplastic procedures to allow breast conservation and a satisfactory cosmetic outcome

Richard M. Rainsbury, Krishna B. Clough, Gabriel J. Kaufman, Claude Nos and J. Michael Dixon

Part 1

Volume replacement techniques to improve cosmetic outcomes after breast-conserving surgery

Richard M. Rainsbury

Introduction

Breast-conserving surgery (BCS) combined with radiotherapy has become the treatment of choice for the majority of women presenting with primary breast cancer over the last 20 years.

A number of prospective randomised trials have compared BCS with mastectomy, showing a survival rate that is unrelated to the type of surgery performed,1–4 although local recurrence (LR) rates smay be higher when the breast is conserved.¹

The risk of LR is related to a number of factors, including positive margins, tumour grade, extent of in situ component, lymphovascular invasion and age. Whole-breast section analysis techniques have been used to show the likelihood of complete excision of unicentric carcinomas using different margins of excision (see Chapters 4 and 15).

Holland et al.⁵ showed that a margin of 2 cm would eradicate all microscopic disease in about 60% of cases compared with a margin of 4 cm, which increases this figure to about 90%.

Local recurrence and cosmetic outcome

The margins of clearance and to a lesser degree the extent of local excision during BCS are strong predictors of subsequent LR.⁶

The extent of local excision remains a controversial issue in BCS. The wider the margin of clearance, the less the risk of incomplete excision and thus potentially of LR (Table 6.1), but the greater the amount of tissue removed, the higher the risk of visible deformity leading to an unacceptable cosmetic result. This clash of interests⁸ is most evident when attempting BCS in patients with smaller breast–tumour ratios, for example when planning BCS for a 10-mm tumour in a 200-g breast or a 5-cm tumour in a 700-g breast.

Table 6.1

	Quadrantectomy	Wide local excision
Margin (cm)	2–4	1–2
Clearance (%)*	< 90	< 58
Recurrence (%)^†	2	7
Cosmesis	Fair	Good

^*Holland et al.⁵

^†Veronesi et al.⁷

The chances of a poor cosmetic outcome are increased still further when the tumour is in a central, medial or inferior location.⁹^,¹⁰ Cosmetic failure is more common than generally appreciated, occurring in up to 50% of patients after BCS.^11–15 A number of factors are responsible, including volume loss of more than 10–20% leading to retraction and asymmetry, nipple–areola displacement or distortion, the use of ugly and inappropriate incisions, and the local effects of radiotherapy. Volume loss underlies many of the most visible and distressing examples of poor cosmetic outcome and the effects may be compounded by associated displacement of the nipple–areola complex (NAC). Poor surgical technique leading to postoperative haematoma, infection or breast tissue and fat necrosis will increase the amount of scarring and retraction, and add to the risks of deformity. Moreover, the use of suction drains, inappropriate incisions and en bloc resections can worsen the cosmetic result still further.

Role of oncoplastic surgery

The interrelationship between breast–tumour ratio, volume loss, cosmetic outcome and margins of clearance is complex, and the widespread popularity of BCS has focused attention on new oncoplastic techniques that can avoid unacceptable cosmetic results. Until now, surgical options have been limited to BCS or mastectomy, the choice depending on fairly well-defined indications and factors. Oncoplastic techniques provide a ‘third option’ that avoids the need for mastectomy in selected patients and can influence the outcome of BCS in three respects:

1. Oncoplastic techniques allow wider excision of breast cancers without risking major local deformity.

2. The use of oncoplastic techniques to prevent deformity can extend the scope of BCS to include patients with 3–5 cm tumours, without compromising the adequacy of resection or the cosmetic outcome.

3. Volume replacement can be used after previous BCS and radiotherapy to correct unacceptable deformity ¹⁶ and may prevent the need for mastectomy in some cases of local recurrence when further local excision would result in considerable volume loss.

Choice of oncoplastic technique

The choice of technique depends on a number of factors, including the extent of resection, position of the tumour, timing of surgery, experience of the surgeon and expectations of the patient. Reconstruction at the same time as resection (breast-sparing reconstruction) is gaining in popularity. As a general rule, it is much easier to prevent than to correct a deformity that has developed as the sequela of previous surgery. Immediate reconstruction at the time of mastectomy is associated with clear surgical,¹⁷ financial¹⁸^,¹⁹ and psychological²⁰ benefits, and similar benefits are seen in patients undergoing immediate breast-sparing reconstruction after partial mastectomy.

Resection defects can be reconstructed in one of two ways: (i) by volume replacement, importing volume from elsewhere to replace the amount of tissue resected; or (ii) by volume displacement, recruiting and transposing local dermoglandular flaps into the resection site. Volume replacement techniques can restore the shape and size of the breast, achieving symmetry and excellent cosmetic results without the need for contralateral surgery. However, these techniques require additional theatre time and may be complicated by donor-site morbidity, flap loss and an extended convalescence. In contrast, volume displacement techniques require less extensive surgery, can limit scars on the breast and limit donor-site problems. These procedures may be complicated by necrosis of the dermoglandular flaps and contralateral surgery is usually required to restore symmetry as volume loss is inevitable (Table 6.2).

Table 6.2

Comparison of techniques for breast-conserving reconstruction

	Volume replacement	Volume displacement
Symmetry	Good	Variable
Scars	Breast + back	Periareolar inverted-T
Problems	Donor scar Seroma flap loss	Parenchymal necrosis Nipple necrosis Volume loss
Theatre time (hours)	2–3	1–2 (per side)
Convalescence (weeks)	4–6	1–2
Timing	Immediate or delayed	Immediate > delayed
Mammographic surveillance	Possibly enhanced	Unaffected

A number of factors need to be considered when making the choice between volume replacement and volume displacement. Volume replacement is particularly suitable for patients who wish to avoid volume loss and contralateral surgery after extensive local resections. They must be prepared to accept a donor-site scar and be made aware of the possibility of complications that may result in prolonged convalescence. Volume replacement is equally well suited to immediate and delayed reconstruction and is the method of choice for correcting severe deformity after previous breast irradiation.

Volume displacement techniques are particularly useful for patients with large ptotic breasts who gain benefit from a ‘therapeutic’ reduction mammaplasty that incorporates wide removal of the tumour. Volume displacement is less reliable in irradiated breasts, and patients need to be warned about the risk of asymmetry that may require simultaneous or subsequent contralateral surgery.

Volume replacement techniques

Several different approaches to volume replacement have been developed over the last 10 years, including myocutaneous, myosubcutaneous, perforator and adipose tissue flaps, lipomodelling and implants. Autologous latissimus dorsi (LD) flaps are the most popular option because of their versatility and reliability.

The myocutaneous LD flap carries a skin paddle that can be used to replace skin which has been resected at the time of BCS or as a result of contracture and scarring following previous resection and radiotherapy ¹⁶ (Fig. 6.1). Although the skin paddle adds to the replacement volume, it can lead to an ugly ‘patch’ effect because of the difference in colour between the donor skin and the skin of the native breast.

Figure 6.1 Latissimus dorsi myocutaneous miniflap.

A myosubcutaneous LD miniflap ²¹ circumvents this problem by harvesting the flap in a plane deep to Scarpa’s fascia. This produces a bulky flap without a skin island and includes a layer of fat on its superficial surface that is used to reconstruct defects following wide excision with preservation of the overlying skin (Fig. 6.2).

Figure 6.2 Latissimus dorsi myosubcutaneous miniflap.

Transverse rectus abdominis myocutaneous (TRAM) and deep inferior epigastric perforator (DIEP) flaps are used much less frequently, as the greater risk of these procedures renders them a less attractive choice than LD flaps in this particular situation. Moreover, fat necrosis is a more common complication of abdominal flaps, creating the potential for diagnostic confusion on follow-up.

Perforator flaps ²²^,²³ based on thoracodorsal artery perforators (‘TDAP flaps’) and lateral intercostal artery perforators (‘LICAP flaps’) are gaining popularity. They provide skin and subcutaneous fat for volume replacement, are relatively quick to perform, and appear to be associated with a faster recovery and less morbidity than LD flaps. As the LD is relatively undisturbed, the LD muscle can be used for breast reconstruction if a mastectomy is required for a subsequent local recurrence. TDAP flaps are most suitable for lateral and upper pole defects, while LICAP flaps can be used to reconstruct small to medium-sized lateral pole defects. Neither flap can be transposed sufficiently to reconstruct medial pole defects, which are more suitable for reconstruction by an LD miniflap that has been fully mobilised following divison of the tendon, all the serratus anterior branches of the vessels and all remaining fascial attachments to terres major. Other flaps, such as the lateral thoracic adipose tissue flap, have been described²⁴ but their clinical utility is unclear.

Lipomodelling techniques ²⁵ have been used to correct rather than to prevent deformity after BCS.²⁶ Stem cells harvested from fat are injected around the defect, into underlying pectoralis muscle and overlying subcutaneous fat, avoiding the breast parenchyma. This helps to avoid the confusing mammographic images resulting from areas of calcified fat necrosis in the vicinity of the tumour bed. The theoretical risk of tumour induction by injected stem cells remains a concern, and has led to the somewhat cautious introduction of this innovative technique into clinical practice.²⁶ Some surgeons have started to use lipomodelling at the same time as wide local excision but no long-term results of this technique have yet been reported.

Non-autologous volume replacement with saline or silicone implants has been tried with mixed success.²⁷^,²⁸ Implants can be placed directly into the resection defect or under pectoralis major. They cannot be moulded to fit the resection defect and they form localised capsules, particularly in irradiated tissues. This may interfere with clinical examination and also mammographic surveillance, although there are techniques to allow mammaplasty in breasts with implants and magnetic resonance imaging (MRI) follow-up is an option in such patients. If using implants, low height and low projection implants placed low in the treated breast combined with lipomodelling gives the best results. If there is deformity and significant nipple deviation then a myocutaneous flap is preferred. Autologous tissue transfer is usually the best option for most patients and results in a lifelike breast of normal shape and size.

A number of innovative surgical procedures have evolved that facilitate volume replacement at the time of BCS or at a later date:

1. Resection through a radial incision and LD harvest through an axillary incision.²⁹

This was the original description by Noguchi et al. of the use of LD myocutaneous flaps to reconstruct resection defects during BCS in small-breasted Japanese patients. Radial incisions are not the incisions of choice.

2. Conventional LD myocutaneous flap harvest for correction of major resection defects.¹⁶

3. Resection through a circumferential incision and endoscopic LD flap harvest and reconstruction through an axillary incision.³⁰

4. Resection, LD harvest and reconstruction through a single lateral incision.²¹

Indications for volume replacement

Volume replacement should always be considered when adequate local tumour excision leads to an unacceptable degree of local deformity in those patients who wish to avoid mastectomy or contralateral surgery.

Resection of more than 20% of breast volume, particularly from central, medial or inferior locations, significantly increases the likelihood of a significant and unsightly local deformity,³¹ which results in psychological morbidity.³² In these patients, volume replacement can extend the role of BCS and avoid mastectomy when resecting up to 70% of the breast.

Breast conservation with or without reconstruction was formerly reserved for patients with unifocal tumours, but the much wider excision achieved in patients undergoing immediate volume replacement allows resection of multifocal disease with clear margins and excellent local control.³³ Volume replacement may be inappropriate in those with more widespread disease or locally advanced T4 tumours. Likewise, LD volume replacement is hazardous in patients with a history suggesting damage to the thoracodorsal pedicle or to the LD muscle, and alternative methods should be considered (Box 6.1). Patients should be informed that using LD for breast conservation precludes its subsequent use for later breast reconstruction. If a mastectomy is required to treat recurrent disease, the options include a variety of free flaps or subpectoral implant-based reconstruction.

Timing of procedures

Ideally, reconstruction of the partial mastectomy defect should be performed immediately or within a few weeks of the tumour resection in order to prevent deformity rather than to correct deformity months or years later. The emergence of the multiskilled ‘oncoplastic’ breast surgeon will in future help to circumvent the current problems encountered when organising a ‘two-team’ approach involving breast and plastic surgeons. Moreover, immediate reconstruction is associated with fewer technical problems and complications than delayed procedures. Delayed reconstruction may be compromised by previous radiotherapy, leading to reduced tissue viability and an increased risk of fat necrosis, infection and delayed wound healing.

Immediate reconstruction can be carried out as a one-stage procedure,²¹^,³⁴ which involves simultaneous resection and correction of the resulting defect. This requires perioperative confirmation of complete tumour excision using frozen-section techniques. As an alternative, the procedure can be split into two steps.³⁵ The first step involves excising the cancer and performing a sentinel node biopsy if the nodes are clinically and radiologically normal and the second step includes axillary dissection if required, flap harvest and reconstruction, and is carried out a few days later after confirmation of clear tumour resection margins. Patients undergoing a one-stage procedure must be informed that a mastectomy with or without reconstruction may be required if subsequent histopathological analysis confirms incomplete tumour excision.

Volume replacement with latissimus dorsi miniflaps

There are many similarities between the different surgical approaches used in breast-conserving reconstruction and these can be best illustrated by summarising the main steps involved in LD miniflap reconstruction, which has been described in detail elsewhere.³⁶^,³⁷ This procedure involves the use of a myosubcutaneous flap of LD for immediate reconstruction of a partial mastectomy defect, most commonly in the central zone but also in the upper outer and upper inner quadrants of the breast. The term ‘miniflap’ is somewhat misleading, as the flap needs to be of sufficient volume to replace resection defects resulting from the excision of 150–350 g of breast tissue. Moreover, the miniflap needs to be bulky enough to allow for a small degree of postoperative flap atrophy.

When planning immediate volume replacement, the patient needs to be fully informed about the nature of the procedure and the possibility that a subsequent total mastectomy may be required if partial mastectomy results in incomplete excision. Careful preoperative mark-up of the tumour, the margins of resection and the line of incision are essential. The operation allows simultaneous partial mastectomy, axillary dissection, mobilisation of part of LD (the miniflap) and reconstruction of the resection defect through a single lateral incision. The procedure is greatly simplified by high-quality equipment, which is essential when developing the narrow optical spaces behind the breast and on the superficial and deep surfaces of the miniflap.

The operation involves tumour resection, axillary dissection, flap harvest and reconstruction. First, the tumour is resected in a subcutaneous plane by separating the skin envelope overlying the tumour-bearing quadrant from the underlying breast disc by sharp dissection, using the preoperative skin marks to determine the exact extent of dissection. By developing a mirror-image retromammary space deep to pectoralis fascia, the mobilised tumour-bearing quadrant is gripped firmly between fingers and thumb and resected with a generous margin of normal breast tissue. Four biopsies taken from opposite poles of the resection defect are sent for frozen-section analysis to allow intraoperative assessment of completeness of excision. The cavity wall is inked in situ with methylene blue to identify the inner surface, and then can be re-excised in its entirety if considered necessary. Further bed biopsies can also be examined after re-excising the cavity wall if frozen-section examination of the initial biopsies shows incomplete excision. A mastectomy is performed if these further bed biopsies fail to confirm complete excision. Next, appropriate axillary surgery (sentinel node or axillary dissection) is carried out and the vascular pedicle is prepared.

The third step involves mobilisation of the LD miniflap by developing superficial and deep perimuscular spaces that mirror each other. The myosubcutaneous flap carries a layer of fat on its superficial surface to increase its volume and this is achieved by developing the superficial pocket just deep to Scarpa’s fascia. Division of the miniflap around the perimeter of the dissection pocket and division of the tendon of the LD near its insertion ensures unrestricted transposition of the miniflap into the resection defect. Finally, reconstruction of the resection defect is completed by careful use of sutures to model the flap, before fixing it to the cavity walls.

Perioperative outcomes

The time required for breast-conserving immediate reconstruction with a miniflap lies somewhere between BCS alone and total mastectomy combined with immediate LD reconstruction. Early postoperative complications include infection, flap necrosis, haematoma formation and transient brachial plexopathy,³⁴ although postoperative stay and disability are similar to other types of BCS. Breast oedema is common, particularly after extensive resection, but usually settles within 6–8 weeks. It may be caused by division of multiple afferent lymphatic pathways during retromammary dissection. Donor-site seroma formation occurs in almost all patients, and can be reduced by ‘quilting’ or delaying drain removal. Flap necrosis is rare, and can be avoided by gentle resection and handling of the pedicle and by taking care to prevent traction and twisting injuries during transposition and fixation of the flap after tendon division.

Late sequelae of volume replacement include lateral retraction of the flap, leading to distortion and hollowing of the resection site, and flap atrophy. Flap retraction can be avoided by division and fixation of the tendon and careful suture of the flap into the resection defect. Detectable flap atrophy occurs in a minority of patients followed for up to 10 years.³⁸ It can be counteracted by over-replacement of the resected volume with a fully innervated flap that has been harvested with a generous layer of subcutaneous fat, by using a myocutaneous flap or by later lipofilling.¹⁶

Frozen-section analysis of bed biopsies has been found to correlate closely with the adequacy of excision determined by formal histopathology.³³ Moreover, the use of LD miniflap reconstruction leads to a significant fall in the number of incomplete excisions compared with BCS alone²⁴ without compromising the cosmetic outcome. Sensory loss following miniflap reconstruction is minimal compared with the loss following total mastectomy.³⁹ The sensory innervation of the breast and NAC is largely intact, except over the resected quadrant. Finally, volume replacement preserves symmetry, avoiding the need for alterations to the contralateral breast in almost all patients (Fig. 6.3).

Figure 6.3 (a) Latissimus dorsi myocutaneous miniflap. (b) Latissimus dorsi myosubcutaneous miniflap.

Mammographic surveillance

The mammographic appearance of the partially reconstructed breast compares favourably with the appearances after routine BCS. Symmetry is preserved and the fibres of the isodense flap may be detectable, often associated with a variable zone of radiolucency that corresponds to the layer of surface fat. Flaps may be indistinguishable from the surrounding breast tissue, and important radiological characteristics such as skin thickening, stellate lesions and microcalcifications are easily visualised after flap transfer. Volume replacement does not compromise the early detection of LR,⁴⁰ which typically develops at the junctional zone between muscle and breast parenchyma. The appearance of miniflap on mammograms contrasts with the radiodense distorting stellate scars that are a common source of diagnostic confusion following conventional BCS. Lastly, very few patients develop clinically detectable flap atrophy, with the majority of flaps remaining bulky and functional throughout the period of follow-up.

Future prospects

The role of breast-conserving volume replacement is set to increase as more precise, image-guided resection of specific zones of breast tissue becomes possible. Increasingly sophisticated imaging techniques, such as high-frequency ultrasound and contrast-enhanced dynamic magnetic resonance imaging,⁴¹ may in future enable exact delineation and excision of all malignant and premalignant changes. Endoscopically assisted techniques⁴² may increase the ability to harvest more bulky myosubcutaneous flaps, allowing the reconstruction of more extensive resection defects. This will require the further development of novel techniques for endoscopic dissection,³⁰ including the use of balloon-assisted techniques⁴²^,⁴³ and carbon dioxide insufflation to maintain the epimuscular optical cavities. Current progress is hampered by the use of non-flexible straight endoscopes to carry out dissection over the rigid convex surface of the chest wall.

Deformities following breast-conserving surgery

Until recently, little attention has been paid to the cosmetic sequelae of BCS, as most patients are relieved not to lose their breast and many surgeons are unfamiliar with the plastic surgery techniques that can eliminate postoperative deformities. Moreover, there has been a tendency to recommend delayed reconstructive surgery some time after completion of radiotherapy. Although this is possible, partial reconstruction of the breast after surgery and radiotherapy is technically challenging and requires sophisticated techniques, with cosmetic results that are often disappointing.

In order to better assess the surgical approach for these patients, a classification of the cosmetic sequelae after BCS has been published by Clough et al.⁴⁴^,⁴⁵ This simple classification defines three groups of patients based on clinical examination (Fig. 6.4). The advantage of this classification is that it is a valuable guide for choosing the optimal reconstructive technique, but it is also a good predictor of the final cosmetic result after surgery.

Figure 6.4 Deformities after conservative treatment of breast cancer. (a) Type I: a symmetrical breast with no deformity of the treated breast. (b) Type II: deformity of the treated breast, compatible with partial reconstruction and breast conservation. (c) Type III: major deformity of the breast requiring mastectomy. Reproduced from Clough KB, Claude N, Fitoussi A et al. Oncoplastic conservative surgery for breast cancer. In: Operative techniques in plastic and reconstructive surgery. Philadelphia: WB Saunders, 1999; pp. 50–60. With permission from Elsevier.

• Type I deformities: patients have a treated breast with a normal appearance but there is asymmetry between the two breasts.

• Type II deformities: patients have a deformity of the treated breast. This deformity can be corrected by partial breast reconstruction and breast conservation, with the irradiated breast tissue being spared in the reconstruction.

• Type III deformities: patients have a major distortion of the treated breast, or diffuse painful fibrosis. These sequelae are so severe that only a mastectomy can be considered.⁴⁴

For type I deformities, a contralateral mammaplasty is performed to restore symmetry, avoiding any surgery on the irradiated breast. This is a simple and reliable approach, the irradiated breast serving as the model for a contralateral breast lift or breast reduction. Type II sequelae are almost always postoperative and are the most difficult to treat. A wide range of techniques can be used to repair these defects, from recentralisation of the nipple to the insetting of a flap to reconstruct a missing quadrant. Type III sequelae require treatment by mastectomy and immediate reconstruction with a myocutaneous flap.

Poor remodelling is one of the reasons for an ugly deformity after lumpectomy or quadrantectomy.⁴⁶^,⁴⁷ Some surgeons perform no remodelling at all, leaving an empty defect and relying on a postoperative haematoma to fill the dead space. This may produce acceptable results in the short term but breast retraction of larger defects invariably occurs with longer follow-up, leading to major deformities that are increased by postoperative radiotherapy.¹⁰^,⁴⁴^,⁴⁸^,⁴⁹