Breast Conservation Surgery

History of Breast Conservation Therapy ( BCT)

The initial surgical treatment of breast cancer was typically wide excision but was associated with a high rate of local recurrence and poor survival. William Halsted popularized radical mastectomy in 1894. Radical mastectomy (RM) resulted in a significant drop in the local recurrence rate, but the curative potential remained limited.

Attempt with extended radical mastectomy, which included internal mammary node dissection, failed to improve survival. At different times, Modified Radical Mastectomy (MRM), Total (Simple) Mastectomy, and more recently, Skin sparing mastectomy (SSM) and Nipple-sparing mastectomy (NSM) were introduced.

Although MRM is a less morbid procedure compared to RM, the patient will still require a loss of the breast. The attempt to preserve the breast without compromising survival brought up the use of Breast-Conserving Therapy (BCT). This includes breast-conserving surgery and breast radiotherapy. Although BCT and breast-conserving surgery (BCS) is used interchangeably, strictly speaking, BCT includes both BCS and breast radiotherapy.

BCS is an important part of the breast-conserving therapy, which may be defined as a combination of conservative surgery for resection of the primary tumor with or without a surgical staging of the axilla, followed by radiotherapy for the eradication of the residual microscopic disease of the breast, with or without adjuvant systemic therapy.

The aim of this communication is to highlight the indications, contraindications, surgical techniques, and complications of BCT.

The National Surgical Adjuvant Breast and Bowel Project (NSABP) B 06 compared TM to lumpectomy, with or without radiation therapy, in the treatment of stages I and II breast cancer. After five- and eight-year follow-up periods, the disease-free, distant disease-free, and overall survival rates for a lumpectomy, with or without radiation therapy, were similar to those observed after TM. However, the incidence of ipsilateral breast cancer recurrence (in-breast recurrence) was higher in the lumpectomy group that did not receive radiation therapy.

In short, it is now proven that Breast conservation, when supplemented with adjuvant radiotherapy, is as effective in terms of locoregional recurrence, disease-free survival, and overall survival as total mastectomy

PATIENT’S SELECTION FOR BCT

The four critical elements in selecting patients for breast-conserving therapy are A history and physical examination, breast imaging, histological assessment of the resected breast, and assessment of the patient’s needs and expectations.

CONTRAINDICATION

Relative contraindications are

Factors thought to be associated with the risk of breast cancer recurrence after BCT is now known to be unfounded as long as there is a negative margin on excision. Some of these are:

Age

Positive family history of breast cancer

Skin or nipple retraction (not necessarily sign of locally advanced disease), Tumor location

Limited mutlicentricity

Clinical or pathological axillary nodal metastases,

Aggressive histological subtypes like Triple-negative and HER2 enriched

Presence of an extensive intraductal component on biopsy

Margin Analysis during Breast Conservation Surgery –

During Breast conservation surgery,the most important goal as a surgeon to achieve is excision of the tumor in total adequately with no cancer left behind.  It needs a thorough assessment of the excised specimen during or after surgery; the Specimen is assessed by routine Histopathology after surgery in many institutions in many countries and may warrant the need to re excise 9 redo surgery ) if the margins are positive for cancer in the final report. To reduce the chances of re-excision, we prefer to assess the specimen intraoperatively ( i.e. at the time the surgery only ) and analyse margins.

What constitutes adequate clearance of tumor at the surgical margin? 

The majority of the general literature appears to consider 2 mm as the cut-off point for a negative margin with anything less than that being considered a close margin. We use 1 mm as a cut off for negative margins in its invasive carcinoma and 2 mm for non-invasive carcinoma in situ.

Currently, a positive margin is generally interpreted to mean the presence of tumor, either invasive and/or ductal carcinoma in situ (DCIS), at the surgical resection line. However, lymphatic invasion at a margin is not considered a positive margin. Neither atypical ductal hyperplasia nor lobular carcinoma in situ at the margin is considered a positive margin

At the base of tumour, In the case of a pectoralis fascia margin, a single collagen strand separating tumour from the margin is considered adequate clearance

There are various methods to analyze margins of the resected specimen during surgery ( Intraoperative Margin Analysis Measures). E.g-

  1. Gross Examination

In theory, a mass is clearly identifiable and the distance to various resection margins measurable. In reality, often the mass is irregular with ill-defined tentacles cast out in different directions. An advantage of gross examination is that it is a rapid method of assessing margins and is useful in identifying grossly transacted tumour and close invasive tumours. In the setting of intraoperative consultation, a grossly close or positive margin can be rapidly communicated to the operating room while additional margin assessments are completed. A grossly negative margin has little predictive value unless the margin clearance is several centimetres and the patient does not have extensive DCIS, multifocal disease or invasive lobular carcinoma

  1. Image or Faxitron Analysis

Many institutions confirm resection of lesions using specimen imaging. Conventionally this is a single dimension X-ray with compression of the excision specimen . A smaller set of institutions incorporate 2-dimensional digital specimen mammography (Faxitron) without specimen compression. This may be followed with a second specimen mammogram of the serially sectioned specimen. The Faxitron appears to be better than conventional radiography at delineating microcalcifications and parenchymal distortions near margins, thereby enabling pathologists to select tissue for microscopic assessment. In the setting of intraoperative consultation, immediate reexcisions can be performed resulting in tumor-free resection margins at the time of the primary surgery. The sensitivity of the Faxitron appears to range from 78.6–85.6% for magnification of 1.0–2.0 : 1.0, with a specificity of 100%. However, if the Faxitron equipment and the ability to interpret the images is not housed within the pathology suite, there can be a significant time delay with its use in intraoperative consultation.

Specimen mammography- it’s the mammography of the transacted specimen. It’s especially useful to collude the complete excision of impalpable lesions like microcalcifications. The mammography images of excised tissue are compared with images of preoperative mammography.

  1. Touch Imprints or Smears of Margins

An imprint (touch) or a scraping of the specimen surface, placed on glass slides and stained using either hematoxylin and eosin or diffquick, can be used to evaluate for tumour cells in a specimen margin. This method is employed only in the setting of intraoperative consultation. The advantage of this method lies in the fact that it does not alter the specimen, which can be later imaged, fixed, and/or sectioned. The disadvantages are many: the requirement for multiple imprints, the associated time consumption, the dependency on close visual inspection of the specimen, the ability to only detect transacted disease, lower sensitivity, and the inability to measure the width of clearance. It is reported a sensitivity, and specificity of 100% for the use of touch preparation cytology in the evaluation of surgical margins in breast cancer. The sensitivity and specificity of the method in re-excision margin assessment, however, is reportedly only 75% and 82.8%, respectively, producing a PPV of 21.4% and a NPV of 98.2%

  1. Intraoperative Frozen Section (FS)

Mammary tissue is notoriously technically difficult to cryosection because of its adiposity. Freezing also introduces tissue artifact in the form of architectural distortion and resistance of adipose tissue to sectioning. In addition, if the tissue submitted for evaluation is more than one centimeter in largest dimension, there is the added risk of sampling error. This method therefore is not popular amongst most pathologists. Surgeons, however, like the method because it enables rapid microscopic examination of tissue during surgery and it can be used to determine the extent of surgery to be performed in a single operative setting. However, the use of frozen section for multiple margin assessment is time consumptive and adds significantly to operating time. In order to provide good turnaround for multiple margin assessments, a pathology frozen section suite would have to be equipped with multiple cryosectioning units and have reserves in both equipment and personnel so as not to impact other surgeries. More importantly frozen section alters the appearance of tumors, particularly ductal carcinoma in situ and infiltrating lobular carcinoma and benign lesions such as intraductal papillomas and sclerosing adenosis. The ability to read through the artifact and not call a benign lesion malignant or a malignant area benign is dependent on the skill and experience of both the pathologist and the entire frozen section staff.

Cendan and his group performed a retrospective analysis of FS margin accuracy compared to permanent sections and showed an 84% concordance per case, with 24% of the patients requiring immediate re-excision intraoperatively of the lesion and approximately 20% of patients needing second surgery due to false negative margins. Expectedly, invasive lobular carcinoma and DCIS cases had higher rates of false negative FS margins. In addition, 51.2% of all patients with positive margins had at least one false-negative margin on either the primary or secondary excision.

Osborn et al. compared the cost-effectiveness of routine FS analysis of breast margins against reoperation for positive margins assessed by routine examination of the resected specimen. Their experience has shown that the use of FS for margin assessment with the attendant increased operative time provide cost savings only when the re-excision rates are greater than 36% . The use of intraoperative assessment of margins is driven in part by patient demographics. Institutions which have a large patient population that travels long distances for surgical treatment will spend more resources in attempting to achieve tumour-free margins at primary excision to avoid second surgeries than medical centres whose patients are local and who can readily return for a second procedure if needed. The expense and inconvenience of patients having to return from great distances is balanced against the greater expenditure of operating room time. Besides in the community like ours in India, cost is always a factor driving the decisions. If you consider second surgery , it is definitely costlier than the added cost of increased operation theatre time during first surgery and intraoperative frozen analysis.

Shave Margins

Surgically, a shave margin is a thin piece of tissue obtained by shaving the surface of a lumpectomy cavity or other excision surface. This tissue will have two surfaces of interest: the original margin and the new margin surface. These two surfaces are differentially inked to maintain the identification of the two margins. Most shave margins are large enough to require serial sectioning with the submission of multiple tissue sections for microscopy to completely assess for presence or absence of disease. The pathologist can trace disease, if present, from the original margin to the new margin. Any disease present can be measured for distance from the “final” margin.

A shave margin taken by a pathologist is a very thin slice of tissue from a margin surface in question and is usually a size that can be frozen for microscopic intraoperative examination or placed directly in a tissue-processing cassette. Any tumor present in the section examined would indicate a positive margin. In the intraoperative setting, relatively larger surface areas can thus be examined compared to that of a perpendicular section through a margin, providing a yes or no answer. Disadvantages of a shave margin include difficulty in obtaining a shave of a soft surface and in maintaining tissue orientation. The nature of the section also precludes measurement of the clearance of a tumor from a margin. Pathologic shave margins for the permanent sections are most commonly used to assess margins that are distant from a tumor and are required for completeness of reporting margin status.

Alternative methodologies for margin assessment have emerged recently.

Intraoperative Optical Coherence Tomography (OCT) is a high-resolution imaging technique involving real-time exvivo microscopic images and another one is Margin Index. But these are not yet widely accepted /used.

Breast Conservation Surgery

breast-conserving surgery ( BCS) is also known as wide local excision / partial mastectomy because — unlike a mastectomy — only a portion of the breast is removed. Surgeons may call it a Lumpectomy too.

During BCS, a small amount of normal tissue around the lump (also described as clean or normal margins of breast tissue) is also taken to help ensure that all cancer or other abnormal tissue is removed. There are various methods to assess the completion of tumor removal  We prefer specimens to be examined for instant histopathological analysis, called a Frozen section, to confirm free margins and the complete removal of cancer. Your surgeon gets the result of the findings of the pathologist in real-time during surgery. If there are chances of cancer left behind, your surgeon re-excises that portion till he gets optimum negative margins.

Axilla ( armpit) is treated as per status of Lymph node metastasis , proven before surgery. i.e. axillary clearance for proven lymph node metastasis and if not, then it is subjected to sentinel lymph node biopsy and analysis of nodes by frozen section. If frozen section shows lymph node involvement by cancer, you will be subjected to full axillary clearance. ( see for more details; Sentinel Lymph Node biopsy and axillary staging )

If there is loss of less than 20 % of breast volume during cancer resection, the breast shape is not usually distorted nor would there be disparity in shape and symmetry. Its may not be necessary to reconstruct the defect and the incision would be closed primarily.

If the volume loss is between 20 – 30 % of original breast volume, it needs to be reconstructed to maintain shape an symmetry. It can be achieved by simple displacement techniques (see for more details :Breast Oncoplastic Surgery Type I)

If the volume loss is 30- 50%, It needs to be replaced by the tissue in order to maintain the volume, shape and symmetry of breast after resection. The Tissues can be to be borrowed from surrounding area of body in the form of perforator flaps  ( See for more details ; Volume Replacement Techniques : Breast Oncoplastic Surgery Type II: chest wall perforator flaps). Sometimes the breast are Large and ptotic. In such cases, the tumor is excised by Reduction Mammoplasty techniques, to reduce the breast size and give them better contour. The opposite breasts are operated to maintain symmetry.

If the volume loss is more than 50% , it needs a major replacement to maintain volume and shape. It can be achieved by mobilizing major volume of  your body tissue in the form of pedicelled / free microvascular flaps ( for more details, see: Pedicelled flaps: Free Microvascular Flaps)

Incision of Breast Conservation Surgery –

There are various incisions for Breast conservation surgery. Incision is designed by your surgeon before you being taken into the operation theater and its discussed with you beforehand.

The incision is designed by taking into account of various factors like

tumor size, Its distance from Nipple areolar complex, its adherence to overlying skin, Biopsy site, the choice of reconstruction procedures etc.

Here are few examples of incisions-

Radial and circumareolar

Periareolar

Crescent mastopexy

Round block / doughnut mastopexy

Batwing

 

Hemibatwing

 

Triangle

Radial eclipse

Inframammary

After the procedure

After your surgery, you can expect to:

Probable complications

There are chances of

Next therapy –

Once the drain tube & sutures are removed and wound is healed completely, You will be guided for your next adjuvant therapy. It’s usually decided in a tumour board consisting of  all the subspecialties by discussing your final histopathology report of surgical specimen, your cancer stage, type of cancer, comorbidities and your general health status.