General anesthesia is required. The main indication is breast cancer that is not
amenable to breast conservation due to size, location, contraindication to radiation
therapy, local ulceration/extension, the presence of multiple cancers in different
quadrants of one breast, or patient preference. Some patients prefer mastectomy
with or without delayed reconstruction.
The advantages to mastectomy include a
lower incidence of local recurrence and a new breast cancer, avoidance of radiation
therapy for selected patients, and possibly better cosmetic result with immediate
reconstruction especially for patients with large tumors, small breasts, or tumors
defi nitive level I/II axillary dissection, is usually included at the same operation as
the mastectomy (Fig. 2.4 ). The arm is typically “free draped” to the elbow allowing
good access to the axilla. A transverse or oblique elliptical incision is usually used,
including the nipple-areolar complex, any involved skin, and any recent biopsy incisions.
Subcutaneous saline, vasoconstrictive agent, and/or local anesthetic is used
by some surgeons for defi ning the subcutaneous plane for dissection and hemostasis.
Superior and inferior skin fl aps are raised to expose the breast for resection.
The borders of the dissection are the lateral edge of the sternum, the clavicle superiorly,
the latissimus dorsi laterally, and the rectus sheath inferiorly. Then the breast
is dissected off the pectoralis muscle (the pectoral fascia is preferably left intact if
immediate reconstruction with implants or expanders is anticipated) with care taken
to control perforating vessels. The lateral attachments of the breast are left intact until
the axillary dissection is completed. The breast is retracted laterally and the lateral
border of the pectoralis major is identifi ed. Axillary dissection (see separately) is inferior
to the axillary vessels. Suction drains are used to drain the chest wall and axilla by
most surgeons, but some do not. The skin fl aps are trimmed, if necessary, to achieve
a fl at chest wall and a straight scar. An absorbable interrupted deep dermal suture is
usually used followed by a monofi lament absorbable subcuticular skin suture.
Anatomical Points
The anatomical base of the breast extends from the inferior clavicle to the
inframammary fold and from the lateral sternum into the axilla. Occasionally, islands
of breast tissue exist in the axilla, isolated from the axillary tail. The nipple-areolar
complex and main breast mass may vary considerably between individuals, with
age and posture. A breast mass can be located anywhere within the breast. The size
and nature of the mass and breast essentially determines the placement and type of
incision, surgical result, and cosmesis. The possibility of mastectomy or further surgery
is often a consideration in preoperative placement of incision. Care should be
taken to avoid downward repositioning of the nipple with large excisions, notably
the lower breast tissue. This deformity may be avoided by mobilizing nearby normal
breast tissue into the area of the defect. Cancer specimens involving the nipple
by direct extension require removal of the nipple as part of the segmental resection.
Invasive cancer may invade any of the structures surrounding the breast including
the skin, the pectoralis muscle, the ribs, and the chest wall. Usually very large
cancers that invade one of these structures will be initially treated with neoadjuvant
chemotherapy prior to operation. Occasionally a duplicated axillary vein is present.
Variations in the vascular structures of the axilla are uncommon, but care should
be taken to identify the important neurovascular structures during axillary surgery.
There are reports of aberrant slips of muscle that span the axilla. They may be lowlying
deltoid fi bers or, more commonly, a slip of latissimus extending anterior to
the axillary vein.
Perspective
See Table 2.5 . Despite the extent of surgery, major complications are usually not
severe or frequent and are mostly related to the axillary surgery. The most signifi cant
complications are hemorrhage, development of a large hematoma, infection, abscess
formation, and the requirement for further surgery due to these. Hemorrhage after
mastectomy is usually caused by perforating vessels that retract into the pectoralis
muscle and then bleed when the patient coughs or moves postoperatively. Seroma
is fairly common and usually occurs after the drains are removed. If the seroma is
small, it can be allowed to resolve on its own. If it is larger, it may be aspirated or a
drain may be replaced. Drains are often removed when their output is <50 ml/day.
Lymphedema of the arm is a complication of axillary clearance that occurs in
3–80 % of patients who undergo axillary dissection. Severe lymphedema is rare,
but often unpredictable. Intercostobrachial nerve injury is common and results in
sensory changes to the upper inner arm and axilla. Patients complain of numbness
and tingling as well as changes in sweating. The affected area usually decreases
in size over time, but never fully resolves. Pain may occasionally be very severe,
especially during recovery.
Injury to the thoracodorsal nerve leads to paralysis of the latissimus dorsi muscle.
The motor defi cits include slight weakness in arm adduction and internal rotation of
the shoulder. It is not a very disabling injury, and most patients adapt to it well without
changes in lifestyle. Injury to the long thoracic nerve leads to paralysis of the
serratus anterior muscle. This results in winging of the scapula and shoulder pain.
Wound infection is not very common, but it may occur and should be treated
promptly with antibiotics. Skin fl ap necrosis can occur and is usually caused by
making the fl aps too thin, trauma to the skin edges, or the stretching of expanders
serious, complication. It must be recognized promptly. It can happen during injection
of the tumescent solution or during dissection in a frail, thin patient. Incomplete
carcinoma excision and further surgery are extremely rare.
Poor cosmesis, dimpling, skin necrosis, and hypertrophic scarring are usually
less severe, but more frequent complications. There may be some temporary paresthesia
surrounding the incision. Patients often describe it as burning or shooting
pain. Acute postoperative pain is usually controlled with oral pain medication.
Chronic pain is rare. The risk of infection after a partial mastectomy is minimal and
prophylactic antibiotics are rarely indicated. Mastectomy may be followed by the
immediate reconstruction and associated complications of this.
Major Complications/Consequences
The major complications of modifi ed radical mastectomy include hemorrhage, arm
lymphedema, thrombosis, or injury to axillary vein, damage to the brachial plexus,
and injury of the long thoracic nerve. Hemorrhage may be intra- or postoperative.
The latter is recognized by swelling or discoloration of the skin fl aps, large volumes
of blood in the drains, or changes in the patient’s vital signs. Hemorrhage requires
a return to the operating room with evacuation of the hematoma and control of
the bleeding vessel. Transfusion is rare, and there are usually no long-term consequences
of postoperative hemorrhage. Large hematomas require surgical evacuation
. Infection and abscess formation may complicate large hematomas if left
untreated and can spontaneously drain. Draining of infected hematomas can lead to
open wounds that last for months. Recurrent large seromas or lymphatic sinuses
are rare, but also signifi cant complications. Extensive skin fl ap necrosis from ischemia
as a result of very thin fl aps may require dressings and/or excision and rotation
skin fl ap repair. Arm lymphedema can be temporary or permanent varying widely
in the literature from 3 % to 80 %. The incidence, as well as the severity, usually
increases with the number of lymph nodes removed. Other risk factors for lymphedema
include older age, obesity, postoperative infection, and axillary radiation. If
lymphedema is recognized early and treated promptly, the development of chronic,
severe lymphedema may be prevented. Early treatment involves good skin care,
nighttime elevation, fi tted compression garments, avoiding procedures on the arm,
and manual lymph evacuation.
Axillary vein thrombosis may occur at the time of surgery or postoperatively.
It may contribute to arm swelling and discomfort. Acute thrombectomy may be
useful. Axillary vein or artery injury should be repaired using standard vascular
surgery techniques. Proximal and distal control of the injured vessel must be
obtained. Vein narrowing of >50 % should be relieved with a vein patch. The brachial
plexus injury may result from stretch and positional retraction overhead for
a prolonged period or from high dissection above the axillary vein. Microsurgical
nerve repair may be required. Stretch and strain injuries usually resolve with time
and physical therapy. Long-term brachial plexus injuries are rare, but devastating.
Injury to the long thoracic nerve to serratus anterior muscle results in a winged
scapula and shoulder pain. Physical therapy can improve the condition somewhat.
Pneumothorax is very rare, but potentially fatal.
Angiosarcoma of the upper extremity, known as Stewart-Treves syndrome and
usually associated with postoperative radiation, is very rare, but may develop many
years after modifi ed radical mastectomy. It is fatal if not recognized and treated early.
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