Free TRAM Breast Reconstruction 

Updated: Jun 25, 2021
Author: Michael R Zenn, MD, MBA, FACS; Chief Editor: James Neal Long, MD, FACS 

Overview

Background

Breast reconstruction entered the modern era when Hartrampf, Scheflan, and Black introduced the transverse rectus abdominis myocutaneous (TRAM) flap in 1982.[1] This ingenious procedure reliably transfers autogenous tissue for reconstruction and has the added benefit of abdominal rejuvenation. The TRAM flap has proven to be the autogenous tissue of choice for breast reconstruction.[2, 3]

The main advantage of the procedure lies in the consistency of the reconstructed breast; it is similar to the natural breast in softness and in the way the tissue drapes on the chest. Because the tissue is part of the patient's body, it does not incite foreign-body reaction or capsular contractures, which have plagued implant reconstructions. Furthermore, since scars fade and tissues soften, the reconstruction only improves over time, which is not true of implant reconstructions.

Since the inception of the TRAM flap, surgeons have developed different methods to improve blood supply to the transferred abdominal tissues. These methods currently include use of a midabdominal TRAM flap, a bipedicled TRAM flap, a microvascular augmentation (supercharge) of a unipedicled TRAM flap, a "delay" of a unipedicled TRAM flap,[4] and a free-tissue transfer (or free) TRAM flap, which includes perforator flaps. Of these procedures, only the free TRAM flap takes full advantage of the primary blood supply (inferior epigastric blood vessels) of the TRAM flap tissues. This technique completely removes the abdominal tissues from the body and transplants them to the chest area.

A diagram is shown below.

Diagram of the blood supply to the free transverse Diagram of the blood supply to the free transverse rectus abdominis myocutaneous (TRAM) flap. Note that the deep inferior epigastric vessels supply the flap, the primary blood supply to the lower abdomen. The shaded areas of the flap are discarded.

The blood supply is furnished by microscopic reconnection of the inferior epigastric artery and vein(s) at the mastectomy site. While this procedure is more technically exacting and formidable compared with other TRAM techniques, experienced microsurgeons routinely perform free-tissue transfers with success rates of more than 98% at most centers. When performed properly in the properly selected patient, the free TRAM flap procedure may produce a breast reconstruction superior to that of any other technique.

 

Epidemiology

Frequency

This procedure recently accounted for approximately 20% of breast reconstructions performed in the United States.

Indications

Consider free TRAM flap reconstruction for any patient undergoing mastectomy, either as an immediate procedure (at the time of mastectomy) or as a delayed procedure (some time after mastectomy). Simultaneous bilateral breast reconstruction may be performed with 2 free TRAM flaps. The patient must be psychologically motivated and have adequate tissues in the abdominal area to be considered for a free TRAM flap. Implant reconstruction and tissue reconstruction may be considered for any patient, though the following relative indications favor the free TRAM flap procedure.

  • Division of the superior epigastric blood supply by previous surgery, making a pedicled TRAM flap impossible

  • Radical mastectomy defect with large tissue requirement

  • History of radiation to the chest wall

  • Large opposite breast (difficult to match with an implant)

  • Small opposite breast (difficult to match with an implant)

  • Previous failure of implant reconstruction

  • Excess lower abdominal tissue and patient desires abdominoplasty

  • Desire to maximize or preserve abdominal muscle function[5, 6, 7]

  • Desire to have the maximum possible blood supply to the TRAM tissues[6]

Relevant Anatomy

The flap skin and fat of a free TRAM flap reconstruction survive on perforators through the rectus abdominis muscle. Although this muscle has a dual blood supply (ie, the superior and inferior epigastric arteries), this operation relies only on the inferior epigastric arterial system. Since this is the primary blood supply of these tissues, excellent vascularity is noted over most of the TRAM flap, even in tissue not directly adjacent to the muscle perforators. Only a small cuff of rectus abdominis muscle is harvested with the flap, thereby limiting dissection of the abdominal wall and postoperative discomfort.

In patients with favorable anatomy, all muscle can be preserved and only the perforating vessels are taken with the flap (so-called perforator flaps). If the primary vessels used are the deep inferior epigastric artery and vein, the flap is called a deep inferior epigastric perforator (DIEP) flap.[8] If the primary vessels used are the superficial inferior epigastric artery and vein, the flap is called a superficial inferior epigastric perforator (SIEP) flap.

Because ultimate abdominal discomfort and function can be similar for patients after operations involving traditional free TRAM flaps and perforator flaps, some microsurgeons do not believe the added operative time and risk of dissecting only the perforators are indicated. However, data suggest less abdominal morbidity and lower requirements for pain management for the perforator flap patient. In the final analysis, the type of free-tissue transfer performed depends on the patient's desires and anatomy and the surgeon's experience and preference.[8, 9, 10]

Contraindications

The free TRAM flap operation is major surgery and should not be undertaken lightly by the patient or surgeon. Fifteen years' experience with these procedures enables the author to identify the following characteristics that place patients at higher risk for complications:

  • Cardiac disease (ie, myocardial infarction, angina, congestive heart failure)

  • Pulmonary disease (ie, emphysema, chronic obstructive pulmonary disease)

  • History of pulmonary embolus or deep venous thrombosis

  • Collagen-vascular disease, lupus, scleroderma, polyarteritis (small-vessel disease)

  • Unstable psychiatric disease

  • Obesity (>25% above ideal body weight)

  • Age (physiologic age >70 y)[11]

  • Cigarette smoking and unwillingness to quit

  • Previous surgery that has interrupted blood supply to the TRAM flap

  • Previous surgery, irradiation, or anatomy that is unfavorable to harvesting the tissues or that makes reconnection at the recipient site impossible (often can be determined only at the time of surgery)

  • Contraindication(s) to anticoagulation therapy

Because of the magnitude of the procedure and the degree of stress on the lungs and heart, this operation may unmask baseline cardiopulmonary disease and result in a complicated postoperative course. In addition, anything that causes small-vessel disease, such as the medical conditions listed above or cigarette smoking, may cause complications in the transferred tissue and in the abdominal donor site. Any of the above characteristics contraindicate a TRAM flap procedure; in such cases, the surgeon should seek another method of reconstruction.

 

Workup

Laboratory Studies

Preoperative laboratory examination is directed by the patient's medical condition. At minimum, obtain the following:

  • CBC count

  • Electrolytes

  • Urinalysis

  • Blood type and screen

Imaging Studies

See the list below:

  • Chest radiograph(s)

  • Contralateral mammogram within 6 months

Other Tests

See the list below:

  • ECGs

 

Treatment

Surgical Therapy

Multiple procedures are required for a successful free TRAM flap breast reconstruction.

Stage I - TRAM flap

This may be performed at mastectomy or afterward. If irradiation of the chest is planned, delaying the TRAM flap procedure is recommended in order to limit scarring and deformity of the flap from radiation injury, a phenomenon that has been documented even years later. Belly tissues are used to create the breast mound, and this stage may include a procedure on the opposite breast for optimal symmetry. The operation may last from 4-8 hours. Unlike with pedicled TRAM flaps, the surgeon must spend time finding recipient vessels, which usually involve the thoracodorsal, axillary, circumflex scapular, internal mammary, or thoracoacromial systems. Occasionally, vein grafts are necessary. During this procedure, 90% of the reconstructive work is performed.[12]

Stage II - Revisions and nipple reconstruction

Approximately 3-4 months after the TRAM flap procedure, tissues settle enough and scar tissue relaxes sufficient to allow small revisions and reconstruction of the nipple. Often, these procedures can be performed in an office setting. Chemotherapy should be completed with a 4- to 6-week additional waiting period before further surgery.

Radiation therapy may result in an additional delay of 6 months or longer from the last radiation treatment. At this stage, if some loss of the transferred tissues results in fat necrosis, removing these firm areas and reshaping the mound (to allow a soft breast reconstruction) allows the patient to more easily perform self-examinations to monitor for cancer recurrence.

If the breast-mound revision is major, nipple reconstruction is delayed another 3-4 months to ensure accurate positioning. Nipple reconstruction can be performed as a local tissue rearrangement or as a graft from the opposite nipple. The anatomy of the patient and the preference of the surgeon dictate the choice.

Stage III - Nipple and areolar tattoo

This final procedure, which is performed in an office setting, adds color to the breast reconstruction. This finishing touch to the reconstruction helps make the reconstructed breast more symmetric with the opposite breast and minimizes the visual effect of other scars that may be present on the breast mound. The tattoo is usually performed 2 months after the nipple reconstruction, because scar tissues are softer at this juncture and can better accept the tattoo pigment.

Preoperative Details

Consultation is required for the patient to understand the magnitude of the procedure she is about to undergo. Consultation should include discussion of possible complications and unavoidable scars, along with the opportunity to view pictures of an average TRAM flap result. For some women, speaking to a patient who was once in a similar situation is helpful. Answer all questions so that the patient has realistic expectations.

The degree of preparation necessary for such a large procedure is often limited by the need to perform the mastectomy in a timely fashion. Preoperative instructions include the following:

  • Abdominal conditioning: The patient should perform abdominal exercises to strengthen the muscle to be used and to improve blood supply to the muscle.

  • Perform bowel preparation the day before surgery.

Intraoperative Details

In planning the location of the TRAM flap, remember that it is advantageous to leave the scar as low as possible, similar to the scar left after an abdominoplasty. However, the patient should remember that the location of the fat ultimately dictates the location of the scar. If enough tissue to create a sufficient mound is not present over and immediately adjacent to the muscle, select an alternative technique.

  • An ipsilateral or contralateral vascular pedicle may be used.

  • A small cuff of rectus muscle may be included with the flap harvest. This section of the muscle will be denervated and its function possibly impaired. If the lower abdominal tissues are harvested as a DIEP flap, the muscle and most of the nerve supply may be spared. Although the abdominal wall is less violated with the DIEP flap than with the free TRAM technique, which takes a small cuff of muscle, there is a small risk of hernia and abdominal wall weakness. Because of its anatomy, the SIEP flap does not violate the abdominal wall and, theoretically, should not impair abdominal wall function or cause hernia.

  • No tunnel is necessary to the mastectomy site, as the tissue is completely removed and replanted at the site. This allows the inframammary fold to be definitively set at the initial procedure without fear of compromising the pedicle.

  • Begin abdominal closure with closure of the fascia. This can be performed primarily or with synthetic mesh, depending on the patient's anatomy and the preference of the surgeon.[13]

  • Additional liposuction and skin tailoring may be necessary to achieve an optimal aesthetic result.

  • In most patients, relocation of the umbilicus is necessary, and it appears as a new umbilicus in a position similar to the preoperative position.

  • Shaping and creation of the breast mound expresses the surgeon's artistic abilities. Match the opposite mound by positioning the tissues, folding the flap, and other maneuvers. One advantage of free-tissue transfer is the added freedom to position tissues in any orientation. Pedicled TRAM techniques are tethered by the muscle pedicle and thus have some limitations in flap orientation. The surgeon must always anticipate the effects of healing, scar tissue, gravity, and mound shrinkage during the initial shaping in order to limit the need for revisions. These factors may vary greatly among patients, and the patient should expect revisions.

  • In skin-sparing mastectomy, only the nipple and areola are removed with the breast tissue; the breast skin is spared. In certain patients with small peripheral tumors and negative retroareolar frozen-section biopsy results, the nipple-areolar complex may also be spared. The reconstructive burden is lessened, and most of the skin of the TRAM flap is removed, which allows the breast envelope to be filled with abdominal fat.

Reconstruction images are shown below.

Patient 1. This patient has small breasts and has Patient 1. This patient has small breasts and has a small amount of abdominal tissue available. This is the perfect indication for a free transverse rectus abdominis myocutaneous (TRAM) flap to maximize the amount of tissue available for reconstruction.
Patient 1. Postoperative view. Note the natural pt Patient 1. Postoperative view. Note the natural ptosis of the reconstruction and the distinct inframammary fold, not distorted by a muscle pedicle from the abdomen. The patient does not desire nipple-areolar reconstruction.
Patient 2. This patient has a large opposite breas Patient 2. This patient has a large opposite breast to match and does not desire a breast reduction. A free transverse rectus abdominis myocutaneous (TRAM) flap allows a large block of tissue to be transferred, matching the opposite breast.
Patient 2. Postoperative view. The breast envelope Patient 2. Postoperative view. The breast envelope has been filled with the free transverse rectus abdominis myocutaneous (TRAM) flap. Note the abdominal improvement, an added benefit of the TRAM procedure. The patient still requires nipple-areolar reconstruction.
Patient 3. Preoperative markings. The patient has Patient 3. Preoperative markings. The patient has a large opposite breast and does not desire breast reduction. Note the large amount of skin that will be removed. A free transverse rectus abdominis myocutaneous (TRAM) allows a large reconstruction to match the opposite side.
Patient 3. Postoperative view. There is a good vol Patient 3. Postoperative view. There is a good volume match, and the resected breast skin has been replaced with abdominal skin.
Patient 3. Postoperative view. In this view, note Patient 3. Postoperative view. In this view, note the natural droop of the reconstruction, unobtainable with breast implants. All of the patient's scars are below her tan lines.

Postoperative Details

An uncomplicated free TRAM flap procedure requires 3-4 days of hospitalization.

  • Close observation is required for the first 24-28 hours. Transferred tissues are completely reliant on the microvascular anastomoses; kinking or thrombosis of an artery or vein may mean complete loss of the transferred tissues. To avoid this, perform hourly monitoring by clinical observation and internal or external monitoring with Doppler, laser, oximetry, or temperature devices. Evidence of compromise should prompt reexploration in the operating room.

  • At no time during the first 2 months can the patient put pressure on the transferred tissues. She can only wear soft bras and cannot sleep on the reconstruction. Heating pads are also not allowed near the reconstruction, as the tissues are susceptible to burns because they are denervated.

  • To prevent clot formation in the microsurgical anastomoses, the blood may be thinned during surgery or postoperatively with heparin, warfarin, dextran, or aspirin.

    • This practice varies with the clinical situation and the preference of the surgeon. The Virchow triad relates to the predisposition toward vascular thrombosis and includes intimal injury, diminished flow, and hypercoagulability.

    • Because of its nature, microsurgery routinely deals with injury of the vessel wall from scarring, surgery, and radiation. Diminished flow also occurs, since sutured anastomoses narrow and blood flow is never as good as in the original location.

    • In an attempt to overcome the risk of thrombosis, microsurgeons anticoagulate, or thin, the blood. Although never proven effective, some surgeons routinely use low molecular-weight dextran (25-30 mL/h), heparin (500-1000 U/h), aspirin (80 or 325 mg/d), or warfarin (1-5 mg/d) postoperatively. While heparin and warfarin work on intrinsic clotting factors, dextran and aspirin affect platelet function.

    • All blood thinners may increase bleeding at an operative site, and this occasionally requires discontinuation of the blood thinner. Other common complications include thrombocytopenia with heparin and GI upset and bleeding with aspirin.

  • Ambulation begins on the first postoperative day.

  • To remove tension on the abdominal closure, place the patient in a flexed position at the waist for the first few days; an upright position is possible by the end of the first week.

  • Drain tubes are necessary and are usually kept in place for 1-2 weeks.

  • The patient requires 6-12 weeks to regain her prior energy level and to resume normal activities.

  • Full range-of-motion exercises for the shoulder are begun 10-14 days after the operation.

  • Patients may resume abdominal exercises in 6 weeks or sooner if a perforator flap is performed.

  • Anesthesia of the mastectomy site and central abdomen resolves over the next 6-12 months. The degree of sensory reinnervation to the TRAM flap is variable and patient dependent.[14]

  • Because of the tight closure of the underlying muscle fascia of the abdomen, most patients experience a painless tight feeling for many months.

  • Patients with preexisting back pain may experience an exacerbation of this pain from the procedure.

  • Prolonged convalescence and discomfort coupled with a cancer diagnosis may be depressing and emotionally draining.

Follow-up

Once the patient and surgeon are satisfied with the breast reconstruction, maintenance is minimal.

  • Mammography of the reconstructed breast is not required; there is no breast tissue to visualize; however, simple physical examination for new lumps or masses should be performed by the patient.

  • Examine new lumps or masses by physical examination, mammography, CT/MRI/position emission tomography (PET) scan, or, if indicated, biopsy.

  • If present, fat necrosis is noted early as an area of firmness that does not resolve over time. During the first revision, remove all areas of fat necrosis to obtain a soft mound without palpable masses, allowing for surveillance for recurrent breast cancer.

For excellent patient education resources, visit eMedicineHealth's Women's Health Center and Cancer Center. Also, see eMedicineHealth's patient education articles Mastectomy, Breast Lumps and Pain, Breast Self-Exam, and Breast Cancer.

Complications

The free TRAM flap procedure is performed daily and safely by plastic surgeons experienced with microsurgery. Because of the magnitude of the procedure, complications can occur even in the best hands. Possible complications from a free TRAM flap procedure are listed below. Fortunately, major complications are uncommon.[15, 16, 17, 18]

  • Fat necrosis and/or partial flap loss (5-15% of patients)

  • Complete loss of free TRAM tissue (2%)

  • Seroma (fluid collection, usually in abdominal donor site)

  • Hematoma (bleeding at chest or abdomen)

  • Infection

  • Hernia (1-5%)

  • Abdominal bulge without hernia (5-15%)

  • Deep venous thrombosis and/or pulmonary embolus (< 1%)

  • Death (< 1%)

A study by Mennie et al indicated that the need for hernia repair is increased in patients who undergo abdominally based autologous breast reconstruction. The study, which included 7929 women who underwent breast reconstruction using a DIEP flap or a free or pedicled TRAM flap, found the rate of hernia repair in these women over a 3-year period to be 2.45%, compared with 0.28% in 15,679 women who had mastectomy without breast reconstruction. In addition, the likelihood of hernia repair was highest in free and pedicled TRAM flaps, with the adjusted hazard ratios being 1.81 and 2.89, respectively, compared with DIEP flaps.[19]

A literature review by He et al indicated that the risk of abdominal bulge/hernia in patients undergoing breast reconstruction with a free TRAM flap is 2.87 times greater than with DIEP flaps. However, when patients with obesity were excluded, the relative risk fell to 2.35, and when only muscle-sparing free TRAM flaps were compared with DIEP flaps, the figure was 2.55. The investigators also reported that the risk of flap loss is higher with DIEP flaps than with free TRAM flaps, although the relative risk was lower (1.93) when DIEP flaps were compared only with muscle-sparing free TRAM flaps.[20]

A literature review by Jeong et al indicated that compared with pedicled TRAM flaps, the risk of fat necrosis and partial flap necrosis is significantly lower with free TRAM flaps. However, the investigators found no difference between the two flap types with regard to total flap necrosis and (in contrast to the Mennie study) hernia/bulge.[21]

In a study of immediate unilateral breast reconstruction with free TRAM flaps, Kwok et al determined the return rate to the operating room for vascular anastomosis revision to be 1.72%. In comparison, the rates were 0.0%, 2.66%, and 5.64% for immediate unilateral reconstructions using pedicled TRAM flaps, DIEP flaps, and superficial inferior epigastric artery perforator (SIEA) flaps, respectively.[22]

A study by Moon et al reported that in patients who undergo autologous breast reconstruction with free muscle-sparing TRAM flaps, complication risk factors include a body mass index (BMI) of greater than 25, smoking status, and neoadjuvant radiotherapy. The investigators also found that the procedure‚Äôs aesthetic outcome is affected by  a BMI of over 25, smoking status, contralateral breast surgery, and a history of cardiac and endocrine disease.[23]

 

Questions & Answers