Wednesday, January 13, 2010

SKIN-CONSERVING BILATERAL MASTECTOMY: What, How, If, Who and Why?

OBJECTIVES:

Being identified as high risk doesn't mean the patient will get cancer with 100% certainty, but it does mean that she'll have some important decisions to make. One of which may be whether to have prophylactic (preventive) mastectomy — surgery to remove one or both breasts in hopes of preventing or reducing her risk of breast cancer. Some experts argue that even for high-risk women, prophylactic mastectomy is inappropriate because not all breast tissue can be removed during a surgical procedure.


Our knowledge and technique surrounding determining genetic markers for breast cancer are becoming well developed. We can accurately stage and determine prognosis in women who have already suffered through breast cancer. We can determine risk /benefit ratios and we can determine future heath probabilities with stunning accuracy. When we present a young woman of 20-30 years of age with the alarming possibility of a 90% chance of developing breast cancer in her life time the decision to manage that risk is daunting.


In this article I will discuss this woman’s choices. I will demonstrate the efficacy, method and results of skin conserving mastectomy. We will explore some of the reasons a young woman may opt for that choice.


What is skin-conserving mastectomy?

A skin-sparing operation removes cancerous breast tissue by using the same minimal and judiciously placed incisions used by plastic surgeons for elective breast augmentation. The most common approach is to use a simple, small, circular incision around the edge of the nipple area. The surgeon leaves all or most of the overlying breast skin, preserving the natural skin envelope that can be filled with an implant or with a patient’s own fat tissue from another part of the body.


How is the Surgery Accomplished?

The mastectomy technique has changed dramatically in the past 50 years from the Halsted radical mastectomy, which sacrificed skin and muscle of the chest wall as well as the axillary anatomy. Today it is believed that the skin envelope of the breast can safely be preserved in the absence of direct tumor invasion. The breast tissue and the biopsy scar are included in the resected mastectomy specimen, depending on the clinical circumstance, the nipple areola complex is included in the specimen or can be left intact. In many cases, this can be achieved by performing the mastectomy through an obliquely oriented elliptical incision that encompasses the nipple areola complex (if necessary) and the adjacent biopsy scar. If the diagnosis of cancer has been made by fine-needle aspiration or needle-core biopsy, the mastectomy can be accomplished through a peri-areolar incision in many patients.


Preservation of the infra-mammary fold as well as the skin envelope is critical for an optimum reconstruction. Earlier mastectomy techniques often involved sacrifice of the underlying tissues through the infra-mammary fold area and to the level of the costal margin. This inferior extension is unnecessary for clearance of the cancer. Preservation of the breast skin envelope permits an anatomic reconstruction using either autologous tissue or implants.


The sentinel node approach to the axilla preserves the axillary lymphatic anatomy in the 70% of breast cancer patients who do not have axillary nodal metastases and in whom only the sentinel nodes are removed. Preservation of the axillary anatomy essentially eliminates the risk of lymphedema and post-mastectomy pain syndrome.



A: Incision through which the breast tissue is removed

B: Skin of the breast left in tact to act as the envelope for an implant or an auto-fat transfer


Should Skin Conserving Mastectomy be done? Is it safe?

The main oncological concern in both skin-sparing mastectomy and nipple/skin sparing procedures relates to the possibility of leaving residual tumor within the skin envelope which may manifest later as local recurrence (LR). One large study observed 539 patients over a period of 65 months. 30.6% of cases had non-invasive disease. The LR rate was 5.5%. In most cases, the local recurrence was related to tumor size, grade, nodal status and lymph vascular invasion and was not skin related. After skin-sparing procedures, the overall survival and the local recurrence rate has been reported to be similar to the cases which underwent modified radical or simple mastectomy.


In Skin-conserving mastectomy the endangered breast tissue must be removed with safe margins while the spared skin can still function cosmetically. The ideal procedure would have a flap thin enough to remove most of the breast tissue, but thick enough to support an adequate blood supply. Torresan et al. showed a high prevalence of glandular breast tissue and residual disease in a skin flap thicker than 5 mm. As with standard mastectomy, obtaining free surgical margins is essential to skin sparing mastectomy. While skin flap necrosis is a recognized complication of SSM because the skin envelope's blood supply can become compromised during dissection, this can be minimized by leaving a skin flap as close to 5mm margin as possible and selecting patients appropriate for the procedure. Nicotine, previous radiotherapy, diabetes and obesity increase the risk of skin envelope ischemia, skin necrosis and infection; all these factors could amplify these complications additively.

Who?

There are two main groups of women who desire skin saving mastectomy. Both groups are usually quite young, certainly under 50 years old.

  1. The first faction include the women who have been assessed as very ‘high risk’. These women fall into the following categories:
    • Mutated BRCA genes
    • History of cellular atypia with high risk of DCIS
    • History of lobular carcinoma in situ (LCIS).
    • Higher risk women who have already sought out and received the appropriate genetic and psychological counselling to discuss the psychosocial impacts of the procedure.
  2. The second set of women includes those who have suffered breast cancer and have already been treated with a breast resection, radiation and/or chemotherapy.

Why?


These groups of women have a life-time risk of breast cancer of over 90%. The psychological toll on these women year after year, waiting for the diagnosis they just know is coming or waiting for the other shoe to drop and a re-diagnosis to be made can be devastating.

Another choice is to “manage” the patient’s risk. Managing this kind of risk for a long period of time can be arduous and protracted and indeed, in some locals impossible. The proper management should include:

  1. Surveillance: The goal of surveillance is to detect any possible cancer at its earliest stage.
    • Breast self-exam every month
    • Clinical breast exams once or twice a year
    • Annual mammograms
    • Annual MRI +U/S (offset from the annual Mammogram by 6mos.)
  2. Chemo-preventive drug therapy: This method uses drugs to prevent or inhibit cancer cell production
    • Tamoxifen, a drug used to prevent recurrence in women who have already had cancer, can also be used as a preventive or risk-reducing measure for high-risk women. Side effects include hot flashes, vaginal discharge, an increased chance of endometrial cancer and blood clots
    • Raloxifene is a similar drug to tamoxifen with similar side effects; but raloxifene isn't linked to endometrial cancer.

The Cosmetic Results:

No matter how skilled the plastic surgeon, no matter how proficient the procedure used nothing can compare with the patient’s own external breast as the envelope for the augmentation.


Below are some comparative images of reconstruction methods. The images speak for themselves.




Post-surgical Implants:





Tramflap Reconstruction:








Bilateral Skin Conserving Mastectomy:



SUMMARY:


We are diagnosing breast cancer earlier and earlier. We are able to assess risk/benefit ratios and genetic risks with astonishing precision. Breast cancer is rapidly becoming a chronic, manageable disease rather than a death sentence. The patients we are seeing are younger and younger every year.

Properly placed incisions and skin-sparing, or nipple/skin conserving, surgical approaches provide women undergoing biopsy and surgical treatment for breast cancer with the best option for appropriate cancer eradication while still permitting reconstruction of a more natural looking breast.


Here in Canada and even in the US skin-conserving mastectomy is, more often than not, not offered as an option to the breast cancer or high risk patient. If new surgical techniques can dramatically improved the aesthetic results of mastectomy without sacrificing outcomes should we at least not allow this vulnerable patient to consider this option?