Indications and Patient Selection for Oncoplastic Breast Surgery

Introduction

The newly diagnosed breast cancer patient and her interdisciplinary treatment team must address both the local control (breast) and systemic control (body) issues to minimize the risk of recurrence. From a surgical perspective, the fundamental goals are to remove the tumor with an adequate margin of normal tissue while optimizing the long-term aesthetic outcomes for the patient. The technical decision then becomes whether to proceed with breast conservation therapy (lumpectomy and radiation) or a mastectomy with or without reconstruction. With the pioneering work of the National Surgical Adjuvant Breast and Bowel Project (NSABP), Umberto Veronesi, MD, and others in the 1970s, breast conservation therapy (BCT) has been well established as oncologically safe, offering similar local control rates and equivalent long-term survival rates compared with non-nipple-sparing mastectomy. More recently, nipple-sparing mastectomy (NSM) has been demonstrated to be a third alternative for patients requiring or requesting removal of the breast parenchyma while preserving the skin envelope and nipple–areolar complex (NAC). Breast-conserving lumpectomy and radiation therapy must then be evaluated as an alternative to both nipple-sparing and non-NSM with reconstruction.

The benefits of breast conservation over mastectomy are well established. Clinical outcome studies with 20-year follow-up have demonstrated that breast conservation is equivalent to mastectomy in terms of overall survival. In addition, preservation of the natural breast confers a significant psychological advantage for many women diagnosed with breast cancer. In most cases, preservation of the NAC is possible; therefore, the natural breast elements remain, and the majority of women are happy with the final breast appearance. With the advent of oncoplastic techniques, breast conservation can be expanded to include wider margins of resection and achieve local recurrence rates that are similar to mastectomy. As the reconstructive options have expanded, so has the prevalence of oncoplastic surgery.

There are several differences between traditional breast conservation and oncoplastic surgery. With traditional lumpectomy, the skin is opened directly over the localized lesion. The tumor is then removed, oriented, and sent for pathological evaluation. The skin is closed without attempts to close the internal cavity. For small tumors (either ductal carcinoma in situ [DCIS] or invasive breast cancer), this approach is adequate. Unfortunately, up to 40–45% of patients can be found to have positive margins requiring re-operation to achieve negative margins. Historically, 30% of patients undergoing lumpectomy and subsequent radiation therapy surveyed were found to be dissatisfied with their cosmetic outcome. Cosmetic defects included deformity of the overall shape of the breast, volume loss, changes in the shape and location of the nipple, and Snoopy deformities of the NAC after a transverse incision in the lower central breast. The challenge thus becomes extending the indications for lumpectomy while minimizing the risk of positive margins to optimize the cosmetic results after not only the surgical lumpectomy but also radiation therapy.

In the 1990s, Werner Audretsch, Christian Gabka, and Heinz Bohmert applied reduction mammoplasty and mastopexy concepts to expand the number of patients who are candidates for breast conservation as “oncoplastic surgery.” The term oncoplastic breast surgery is a Greek-derived word that literally means “molding of tumor”; however, in its present context it refers to excision of the tumor (onco) and reconstruction and shaping of the breast (plastic). This often requires a team approach between the oncologic and reconstructive surgeon. Today, the spectrum of oncoplastic surgery includes four basic techniques including:

1.

Local tissue mobilization and rearrangement
2.

Reduction pattern mammoplasty
3.

Skin and nipple rearrangement
4.

Volume replacement

This chapter will discuss the aspects of the tumor characteristics, patient’s anatomy, medical comorbidities, treatment-related issues, psychosexual concerns, and possible complications that affect the indications and patient selection for oncoplastic breast surgery over NSM and non-NSM.

Indications

Oncoplasty enables the breast surgery team to excise more breast tissue, widening the margin of clearance between the tumor and the normal parenchyma. In addition, natural breast appearance is more likely to be achieved, although the volume will be less. These benefits have expanded the number of patients eligible for breast conservation. Many women who are treated with oncoplastic breast conservation surgery would otherwise have needed a mastectomy and/or have had a poor aesthetic result. Fundamentally, the indications for oncoplastic breast surgery are the same as those for breast conservation surgery. Patients should be considered for BCT if they have an adequate tumor-to-breast volume ratio to establish negative margins and are candidates for radiation therapy . All patients undergoing breast-conserving surgery (lumpectomy, partial segmental mastectomy, quadrantectomy, and tylectomy) should be assessed for their oncoplastic needs. The most common indications for oncoplastic breast surgery are tumor size (37%), poor tumor location (22%), oncocosmetic (1%), multifocality (10%), skin retraction (9%), positive margins after previous surgery (5%), and other reasons (5%).

It is also important to identify patients who are not candidates for breast conservation. Historically, absolute contraindications to BCT include (1) patients with a high probability of recurrence due to multicentric disease or the inability to obtain clear margins; (2) patients who are currently pregnant; (3) those with active collagen vascular disease, such as active lupus and scleroderma ; and (4) those with a history of prior breast irradiation either related to prior breast cancer or Hodgkin’s disease. Soft contraindications include (1) patients with a high probability of subsequent breast cancers including those with BRCA1/2 mutations, PTEN, etc.; (2) tumors that directly involve the NAC; and (3) patients with high tumor-to-breast ratios.

The increasing use of neoadjuvant chemotherapy has increased the number of patients eligible for breast-conserving surgery and oncoplastic tissue rearrangement. This is, in part, predicated on the invasive tumor molecular subtype. Neoadjuvant dual HER2 blockade with trastuzumab and pertuzumab in combination with cytotoxic chemotherapy for patients with HER2+ amplification results in a high pathology complete response (pCR) (16.8–66.2%) . Patients with ER+/HER2- cancers have lower pCR rates (7.0–16%), and those with triple negative tumors have 33–35% chances of achieving a pCR ; 40–70% overall will achieve a partial response.

Patient Selection

Comprehensive preoperative evaluation is necessary to determine patients appropriate for oncoplasty and the necessary type of reconstruction. The surgical team should obtain the patient’s history of any prior breast surgery, chest radiation, and infections. Risks factors for wound complications such as diabetes mellitus, active smoking, cardiovascular conditions, history of Ehlers-Danlos, coagulopathies, poor nutrition, and obesity should be noted. Patients with a history of chronic pain, fibromyalgia, and opioid dependence should also be assessed to coordinate optimal care with their primary care provider.

It is also important to understand the patient’s psychosexual concerns and feelings about her breast. Loss of nipple–areolar and breast sensation may be important to patients undergoing breast surgery in terms of quality of life and satisfaction. Patients undergoing skin-sparing mastectomy and NSM can have considerable loss in skin and nipple sensation. Many patients complain of loss of sexual arousal with breast or nipple stimulation after mastectomy. As such, fear of loss of nipple sensation may be an important consideration for oncoplastic tissue rearrangement. Very little data are currently available about the risks of nipple sensation loss after oncoplastic breast surgery and radiation. Concerns about nipple viability, postoperative nipple positioning, fears about the risk of recurrence, and risks of needing additional surgery should be ascertained along with the patient’s history of anxiety. Lastly, patients’ concerns about foreign body implantation and complications, including the remote risk of implant-associated anaplastic large-cell lymphoma, should be addressed.

On physical exam, the surgeon should clinically evaluate the patient’s breast and chest anatomy for breast symmetry, prior scars, bra size, and degrees of ptosis. Enlarged lymph nodes should be assessed for possible regional disease. Patients who have had prior breast conservation and radiation therapy are generally not good candidates for oncoplastic surgery. Diagnostic mammogram, ultrasound, and breast magnetic resonance imaging (MRI) should be strongly considered to precisely identify the location and extent of the breast tumor. Patients undergoing neoadjuvant chemotherapy should undergo another preoperative MRI to assess the extent of the residual tumor and rule out the possibility of disease progression. This will confirm that breast conservation and oncoplastic tissue rearrangement is still possible.

Tumor Characteristics

Invasive Breast Carcinoma

Oncoplastic surgery has been shown to have no adverse effects related to local recurrence, disease-free, or overall survival for all stages of breast cancer.

For patients with invasive lobular carcinoma, extensive microcalcifications, or multifocal breast cancer, the possibility or risk of positive margins is an important consideration for oncoplastic planning.

Ductal Carcinoma In-Situ (DCIS)

The management of DCIS remains controversial to minimize overtreatment and undertreatment. Despite this, margin status is one of the most important determinants in local recurrence and clinical outcomes. The Society of Surgical Oncology (SSO)/ American Society Radiation Oncology (ASRO)/ American Society of Clinical Oncology (ASCO) Consensus Guidelines on margins for DCIS, published in 2016, recommend at least 2-mm margins to reduce the risk of in-breast recurrence relative to narrower negative margins. Parenthetically, the multidisciplinary panel also noted that clinical judgment was necessary to determine whether patients with smaller negative margin widths (≥ 1 mm) require re-excision. They identified additional factors important to consider before additional surgery, including an assessment of residual calcifications on postexcision mammogram, extent of DCIS in proximity to margin, and which margin is close (anteriorly just under the skin and posteriorly excised to the pectoral fascia) versus margins associated with residual breast tissue. The routine practice of obtaining negative margin widths wider than 2 mm is not supported by the evidence.

In a recent case-control study, De Lorenzi et al at the European Institute of Oncology (IEO) compared oncoplastic breast surgery followed by radiation (44 patients) and conservative breast surgery alone followed by radiation (375 patients). The primary endpoints were disease-free survival (DFS) and ipsilateral breast tumor recurrence (IBTR). The tumor size was larger in the oncoplastic group. This was expected as oncoplasty can manage the resection of larger volumes of breast tissue. The average annual rates of invasive IBTR were 1.6% and 1.0% for the oncoplastic and conservative patients, respectively. The authors also found no difference in the rates of contralateral breast cancer distant metastasis and contralateral breast cancer. They observed similar rates of focally involved margins (focally ink on DCIS) in 4.5% and 3.5%, respectively, for the oncoplastic and conservative patients. Close margins (<1 mm) were observed in 22.8% and 17.9%, respectively. None of their patients underwent further surgery. They conclude that oncoplastic breast surgery is a safe and valid treatment component for patients with DCIS.

In a recent review of DCIS, Song et al reviewed their experience at Emory Healthcare System. Twenty-eight patients were included in the study. Therapeutic mammoplasty was the definitive procedure in 64%. There were 10 patients (36%) who required re-operation: 9 for positive margins and 1 for residual microcalcifications. Positive margin rates were independent of tumor location. All 10 patients requiring completion mastectomy or re-excision had intermediate or high-grade disease. In addition, the women requiring re-operation were younger (mean 45.6; median 43) compared with those who did not require re-operation (mean 57; median 57). The authors concluded that oncoplastic reduction techniques are appropriate for DCIS taking into account patient selection and improved confirmation of negative margins. One strategy to minimize the incidence of positive margins is to obtain a preoperative breast MRI, which is useful in determining the extent of DCIS and establishing the boundaries for resection. Intraoperative margin assessment can also reduce the risk of positive margins.

The Impact of the Tumor-to-Breast Size Ratio on Oncoplastic Breast Surgery

In general, women with an A or B cup breast are poor candidates for oncoplastic tissue rearrangement or reduction. They simply do not have enough breast tissue. In this population, small tumors can be excised with local tissue mobilization for adequate closure. Alternatively, the patient may be a candidate for neoadjuvant chemotherapy to shrink the tumor, allowing her to be converted from a mastectomy to breast conservation. If not, the patient may be best suited for mastectomy and immediate implant reconstruction. Figs. 3.1 and 3.2 illustrate a patient with an A cup who completed NSM and two-stage prosthetic reconstruction.