Selecting the Appropriate Timing for Breast Reconstruction after Total Mastectomy
Immediate breast reconstruction
Immediate breast reconstruction usually is reserved for patients with clinical Stage I breast cancer and for some patients with clinical Stage II breast cancer who do not have an increased risk of requiring postmastectomy radiation therapy (PMRT). Unfortunately, although the risk of requiring PMRT can be predicted before surgery,1 the need for PMRT cannot be determined definitively until the final pathologic evaluation is complete.
Immediate breast reconstruction offers many advantages over delayed reconstruction, including a better aesthetic outcome because of preservation of the breast skin envelope2 and the psychological benefit of awakening from mastectomy with a reconstructed breast.3 Many patients find breast reconstruction easier with regard to wearing apparel during exercise or swimming without the worry of a breast prosthesis dislodging, resulting in a potentially embarrassing situation.
Delayed breast reconstruction
Delayed breast reconstruction usually is reserved for patients who will require PMRT. At the University of Texas M. D. Anderson Cancer Center, we prefer not to use breast implants in patients who have received PMRT because of acute problems with wound healing and long-term problems with capsular contracture, which can result in implant displacement and a painful constriction across the chest wall. Thus, we usually perform delayed breast reconstruction using autologous tissue.
It is part of our informed-consent process to advise all patients that clinical information may be used for research purposes. Delayed-immediate breast reconstruction is an approved Internal Review Board clinical protocol (0955–2004) at the M. D. Anderson Cancer Center.
Many of the aesthetic outcomes of delayed reconstruction, even when it is performed by experienced surgeons, are satisfactory at best.2, 3 However, patients who undergo delayed reconstruction after PMRT are the most appreciative, because they have had to experience the difficulties of not having a breast. The retained, irradiated, and scarred breast skin located between the mastectomy scar and the inframammary fold usually is resected at the time of delayed reconstruction, because it is inflexible and does not allow for the reconstruction of a curved and ptotic-appearing breast (Fig. 1A). This not only requires a much larger volume of flap tissue because of the need for skin replacement but also requires recreation of the entire 3-dimensional contour of the breast (Fig. 1B). The need to replace the inferior breast skin means that more flap skin is visible (Fig. 1C). Because of the increased skin requirements, often 75% of the transverse rectus abdominis myocutaneous (TRAM) flap must be used to reconstruct the breast, leaving inadequate tissue for bilateral reconstruction. With delayed breast reconstruction, we also rely more significantly on the ability to perform a contralateral mastopexy (breast lift) to obtain symmetry, because it is more difficult to match the ptotic shape of a contralateral native breast.
Delayed-immediate breast reconstruction
There has been an increase in the use of PMRT in patients with early-stage breast cancer as a consequence of the Danish and Canadian trials.4, 5 Currently, many centers in the U.S. routinely recommend PMRT for patients with breast cancer who have 1 to 3 positive lymph nodes. The increasing use of PMRT in patients with early-stage breast cancer has increased the complexity of planning for breast reconstruction.
If PMRT is required, then delayed reconstruction is usually the best course; however, if PMRT is not required, then immediate reconstruction is appropriate and permits better aesthetic outcomes. However, because lymph node metastases may not be detected until mastectomy5 and because micrometastases may not be detected until the final pathology review,6–9 it is often not known until several days after mastectomy whether PMRT will be required. If breast reconstruction is performed at the time of mastectomy and it is determined postoperatively that the patient has lymph node involvement, then PMRT may affect the aesthetic outcome adversely,1, 10–12 and the reconstructed breast may cause technical difficulties with radiation delivery to the internal mammary lymph nodes, resulting in either increased lung dose or inadequate radiation doses to these lymph nodes.13, 14 Conversely, if breast reconstruction is delayed because physicians suspect that the patient may require PMRT, but the review of permanent sections reveals that PMRT is not needed, then the mastectomy skin and the shape of the breast skin envelope will be lost along with the chance of the best possible aesthetic outcome.
At the M. D. Anderson Cancer Center, we have implemented a 2-stage approach, “delayed-immediate breast reconstruction,”11 to avoid these problems. With delayed-immediate reconstruction, patients who do not require PMRT can achieve aesthetic outcomes similar to those of immediate reconstruction, and patients who require PMRT can avoid the aesthetic and radiation-delivery problems associated with delivery of radiation after an immediate breast reconstruction.
At the M. D. Anderson Cancer Center, patients with clinical Stage II breast cancer are evaluated by a multidisciplinary breast cancer team that includes a radiation oncologist. Patients who are deemed to be at increased risk for conditions that necessitate PMRT and who want breast reconstruction are considered candidates for delayed-immediate breast reconstruction11 (Fig. 2). Although the indications continue to evolve, currently, patients with T2 tumors, 1 biopsy-proven positive axillary lymph node, extensive microcalcifications by mammography, or multicentric disease by ultrasonography have been considered eligible for this clinical protocol. Stage 1 consists of skin-sparing mastectomy with subpectoral insertion of a completely filled, textured saline tissue expander to preserve the dimensions and shape of the breast skin envelope. After review of permanent sections, patients who do not require PMRT undergo immediate reconstruction (Stage 2) (Fig. 3), and patients who require PMRT undergo this therapy with the expander deflated on the chest wall to result in a flat surface to optimize radiation delivery. After the completion of PMRT, patients undergo reexpansion of the preserved breast skin, an approach to reconstruction that we refer to as “skin-preserving delayed reconstruction (Fig. 4).”11
In patients who are deemed not to require PMRT, we prefer to perform Stage 2 (definitive breast reconstruction) of delayed-immediate reconstruction within 2 weeks after mastectomy. After several weeks, the mastectomy skin flaps may lose their elasticity and retain the shape of the expander. Furthermore, delaying definitive reconstruction longer than 2 weeks may interfere with the initiation of adjuvant chemotherapy, which usually starts from 4 to 6 weeks after mastectomy.
Clinicopathologic Factors Can Affect Decision-Making for Breast Reconstruction after Mastectomy
The stage of the breast cancer is critical in reconstructive planning
PMRT occasionally is given after mastectomy to reduce the risk of local-regional recurrence in high-risk patients. Currently, indications for PMRT include large tumor size or direct skin involvement (T3 or T4 tumors) or documented lymph node involvement in ≥4 lymph nodes.15 Patients with clinical Stage I breast cancer are considered to be at low risk for requiring PMRT and, thus, are considered candidates for immediate breast reconstruction using any of the available approaches.
Patients with clinical Stage II breast cancer have a borderline elevated risk of requiring PMRT; therefore, these are the patients for whom it is most difficult to formulate recommendations regarding breast reconstruction timing.10, 11 It is essential that these patients have a careful preoperative evaluation for risk factors for occult axillary lymph node involvement (age < 50 years, lymphovascular invasion in the initial biopsy specimen, and T2 tumor).1 In patients who have any of these risk factors, it may be preferable to avoid the use of breast implants, to perform delayed reconstruction, or to use a delayed-immediate approach.
In patients with clinical Stage III breast cancer (locally advanced), it may be preferable to delay reconstruction until after mastectomy and PMRT to avoid potential problems with radiation delivery and to avoid the possibility of adverse affects of PMRT on an immediately reconstructed breast.10, 12, 16–21 Breast reconstruction has not delayed diagnosis or decreased survival in patients who present with Stage III disease and later develop a local recurrence.22
Clinical Dilemma: Predicting the Status of the Axillary Sentinel Lymph Node
Determining the status of the axillary sentinel lymph node can have a significant effect on the decision whether to perform immediate autologous breast reconstruction and the success of that reconstruction. The current recommendation when a sentinel lymph node is identified as positive is to perform a completion Level I and II axillary lymph node dissection, because additional lymph nodes will be involved in up to 40% of such patients.23, 24 Current practice dictates that, if the intraoperative assessment of the sentinel lymph node is positive, then a completion Level I and II axillary lymph node dissection is performed at the time of the initial operation. Unfortunately, the intraoperative examination of sentinel lymph nodes with frozen-section analysis, imprint cytology techniques, or both does not reveal all micrometastases.7, 8 Conducting an axillary lymph node dissection after sentinel lymph node biopsy and immediate autologous breast reconstruction have taken place can compromise the blood supply to the reconstructed breast, particularly the thoracodorsal vascular system, parts of which often are used as recipient vessels for a free TRAM flap or as a vascular pedicle for a latissimus dorsi myocutaneous flap.1
Recently, consideration has been given to performing axillary sentinel lymph node biopsy prior to mastectomy and breast reconstruction.25 Although premastectomy sentinel lymph node biopsy may be useful to rule out lymph node involvement in high-risk patients, it most likely will not benefit all patients with invasive breast cancer. Currently, only patients with >4 positive lymph nodes are advised to receive PMRT; therefore, if the premastectomy sentinel lymph node biopsy reveals 1 to 3 positive lymph nodes, then the need for PMRT still will not be known until after final review of the complete Level I and II axillary lymph nodes, several days after mastectomy and completion axillary lymph node dissection. Additional considerations include the increased cost, patient inconvenience, and potential complications associated with sentinel lymph node biopsy. Another important issue to consider when using a premastectomy sentinel lymph node biopsy approach is that it is not only axillary lymph node involvement that determines the need for PMRT: The extent of invasive cancer within the breast parenchyma, either alone or in combination with lymph node metastases, can effect the risk of local recurrence and the requirement for PMRT.
Our current approach to immediate breast reconstruction should be reevaluated for patients at high risk of axillary involvement to avoid possibly compromising the vascularity to the reconstructed breast as use of the axillary sentinel lymph node biopsy technique in conjunction with breast reconstruction continues to increase (Fig. 5). In a study published in 2002,1 we proposed a decision-making algorithm for breast reconstruction in patients with clinically lymph node-negative breast cancer (Fig. 6).1 Although the risk to an immediate breast reconstruction could be avoided simply by performing an initial complete Level I and II axillary dissection, because all lymph nodes will be removed without the worry about coming back for more axillary surgery, this practice may impose significant surgical morbidity (lymphedema and shoulder dystocia) in patients whose axillary lymph nodes may turn out to be negative for disease on permanent pathologic analysis.9 Delayed breast reconstruction also may be an option; however, immediate breast reconstruction has well recognized benefits in terms of aesthetics and lessening the psychological effects of mastectomy.26 Although postoperative axillary radiation may be a consideration for locoregional control when the sentinel lymph node is identified as positive on permanent histopathologic analysis, it does not provide the important prognostic information obtained from the additional lymph node tissue.27 When immediate breast reconstruction is performed with either a microvascular TRAM flap (with the most commonly used recipient vessels being the thoracodorsal artery and vein) or a pedicled latissimus dorsi myocutaneous flap, the vascular pedicle may be at risk if subsequent axillary surgery is required. An alternative to use of these vessels for immediate autologous breast reconstruction in patients undergoing mastectomy and axillary sentinel lymph node biopsy that may minimize the risk of vascular damage on reoperation includes use of the internal mammary artery and vein as recipient vessels for a microvascular TRAM flap or use of a pedicled TRAM flap.1 With the use of axillary sentinel lymph node biopsy now routine at our institution, the internal mammary vessels often are our first choice in immediate microvascular TRAM flap breast reconstruction to avoid the potential for vascular injury to the TRAM flap if subsequent axillary surgery is required.
Another confounding factor is the possible need for postoperative axillary radiation when the sentinel lymph node is identified as positive.27 At the time of surgery, it is not known whether postoperative radiation will be required, because findings from the pathologic examination of the additional tissue are not available until several days after the surgery. Therefore, if the intraoperative examination reveals a positive sentinel lymph node, then the decision whether to proceed with an immediate breast reconstruction or to delay reconstruction until after the results of the permanent pathology are known will have to be made beforehand by the multidisciplinary breast cancer team and the patient. The preoperative consultation with the patient should include emphasis on the potentially adverse effects that radiation treatment can have on aesthetic outcome of an immediate breast reconstruction20 and on the technical problems with delivery of radiation to a reconstructed breast.28 At our institution, the decision of whether to proceed with breast reconstruction if the sentinel lymph node is positive or to delay the reconstruction is influenced greatly by existing treatment guidelines.1
Anatomic Considerations are Paramount
Anatomy also is a very important factor in selecting the best reconstructive option. In patients who are relatively thin in the lower abdominal region and have large breasts, consideration can be given to performing reconstruction with a TRAM flap combined with an underlying breast implant.29 Patients who have a diastasis recti with a protuberant abdomen can require more extensive reconstruction of the abdominal wall with synthetic mesh after the harvest of a TRAM flap. Obese patients have an increased risk of fat necrosis of the TRAM flap as well as wound-healing problems at the abdominal donor site.30 Unfortunately, the use of breast implants alone in obese patients usually does not result in a favorable aesthetic outcome. Patients who are extremely thin with small breasts often desire breast augmentation.29 In this situation, the use of a TRAM flap plus an implant is not an option because of the difficulty of closing the abdominal donor site. In these patients, breast augmentation can be accomplished with tissue expansion followed by insertion of a breast implant, but a better result may be obtained with use of a latissimus dorsi myocutaneous flap combined with a breast implant. A latissimus dorsi myocutaneous flap provides the additional skin needed and provides complete muscle coverage of the breast implant, which may decrease the potential for postoperative rippling (irregularities of the implant wall that can be visualized easily under the skin, especially in thin patients). The use of a silicon implant as opposed to a saline implant also can decrease the potential for rippling.
Extensive abdominal scars may complicate TRAM flap reconstruction
Preexisting scars from previous surgeries that lie close to potential donor sites also must be taken into account in determining the optimal method of breast reconstruction.31 Extensive abdominal scars can preclude the use of a TRAM flap. Although an open cholecystectomy scar can preclude the use of a right pedicled TRAM flap, previous laparoscopic incisions and a pfanenstiel incision usually have minimal impact on a TRAM flap. In addition, a latissimus dorsi flap may not be an option for breast reconstruction after a thoracotomy, because the latissimus muscle may have transected.
In patients who present with lower abdominal vertical scars after a hysterectomy, the entire TRAM cannot be used because of inadequate blood supply across the scar (to the side of the TRAM flap opposite the vascular pedicle). This situation can be problematic in large-breasted patients with only a small or moderately thick abdominal pannus in whom a hemi-TRAM flap (50% of the lower abdominal ellipse) will be insufficient to reconstruct an adequately sized breast. A double-pedicled TRAM flap is an option in the large-breasted woman with a lower abdominal vertical scar.
Prior radiation therapy increases the amount of tissue required for breast reconstruction
Another important consideration in determining the optimal method of breast reconstruction is that prior PMRT to the chest wall increases the amount of tissue—mainly skin—required for delayed breast reconstruction.11 Delayed reconstruction after radiotherapy usually requires resection of the retained inferior breast skin (between the mastectomy scar and the inframammary fold) to reconstruct a natural, ptotic-appearing breast. Therefore, delayed reconstruction with a TRAM flap after PMRT often requires the use of 75% of the lower abdominal ellipse of the TRAM flap, including tissue across the midline of the lower abdominal wall. This situation can be even more complex in a patient who also has a lower abdominal midline laparotomy scar. Such patients often require a more complex double-pedicled TRAM flap procedure to provide a blood supply on both sides of the lower abdominal vertical scar. Delayed reconstruction with implants after radiotherapy is not a preferred method because of the potential for capsular contracture,10 which can result in displacement of the implant and patient discomfort from constriction across the chest wall. Although the addition of a latissimus dorsi myocutaneous flap to a breast implant reconstruction will decrease the occurrence of early complications (seroma and infection), it does not appear to reduce the long-term problems with capsular contracture.19
Neither neoadjuvant nor adjuvant chemotherapy has been problematic
Immediate breast reconstruction has not delayed the start of adjuvant chemotherapy, and the administration of neoadjuvant chemotherapy prior to mastectomy and immediate breast reconstruction has not resulted in an increased incidence of complications.32 However, the administration of neoadjuvant chemotherapy can complicate decision-making further in the preoperative determination of which patients will require PMRT, especially in patients who obtain a complete tumor response.
Choosing the Best Method of Reconstruction Is Essential to Optimize the Aesthetic Outcome and to Minimize the Potential for Postoperative Complications
Tissue expansion followed by exchange of the expander for a permanent breast implant: Most rapid recovery, less optimal aesthetic outcome
The tissue-expansion technique involves the initial submuscular placement of a tissue expander, which is an adjustable breast implant that most commonly has an integrated saline-filling port that can be accessed easily by placing a needle through the skin. During postoperative office visits, a magnetic finder is used to locate the integrated port under the skin, and the port subsequently is accessed for saline filling. Tissue expanders are not designed to be used as permanent implants, because they preferentially expand the lower pole of the breast and have a more rugged construction than permanent implants to enable them to withstand the forces of expansion.
The tissue-expansion technique usually requires multiple postoperative office visits for expansion of the breast skin envelope. The time required to complete the expansion process usually ranges from 3 months to 6 months after mastectomy and is dependent mostly on the desired breast size, the thickness of the mastectomy skin flaps, and the patient's ability to tolerate the expansions. Usually, the volume of saline that is instilled into the expander at each visit decreases as the breast becomes larger, because of increasing discomfort from stretching of the scar capsule and backward pressure on the underlying ribs. Despite discomfort, which can last for several days after each expansion, the process usually is not painful.
A disadvantage of the tissue-expansion method, compared with other methods of breast reconstruction, is that it is a 2-stage approach: A second surgical procedure is required to exchange the tissue expander for a permanent breast implant. Another disadvantage—a disadvantage of implant-based reconstruction in general—is the resultant superior fullness, which makes it difficult to create a ptotic-appearing breast. In addition, with unilateral implant-based reconstruction, obtaining symmetry with the contralateral native breast can be difficult. Patients often require a contralateral mastopexy (breast lift) and a contralateral breast-implant augmentation to obtain adequate symmetry.33 Bilateral breast reconstruction with the tissue-expander technique is an easier way to obtain a symmetric result after breast reconstruction (Fig. 7). However, the tissue-expansion method can allow for reasonable breast symmetry when the patient wears a bra, which is the objective of reconstruction for some patients who choose this method. Another consideration with implant-based reconstruction is that, like a breast implant, a tissue expander is a foreign body and, thus, is associated with a risk of infection that may necessitate expander removal.34
An advantage of the tissue-expansion technique and a reason why many patients prefer this method of breast reconstruction is that the surgical and recovery time tend to be the most rapid. Placement of a tissue expander usually takes only 1 to 2 hours, and the hospitalization after mastectomy and expander placement is usually just a few days. The out-of-hospital recovery period is approximately 7 to 10 days. However, the subsequent surgical procedure to exchange the expander for the permanent implant is associated with a similar recovery period.
Latissimus dorsi myocutaneous flap plus a breast implant: Longer recovery than tissue expansion better aesthetic outcome
Reconstruction performed using a latissimus dorsi myocutaneous flap plus a breast implant is more complex than reconstruction performed with an expander and an implant and is associated with a longer recovery period. However, the aesthetic outcome tends to be better—the end result is a more natural-appearing breast. A skin island can be designed overlying the muscle. The combined skin and muscle flap is pivoted under the axilla to the chest wall while remaining attached to the thoracodorsal vessels. The skin island of the flap is used to replace any excised skin, including the nipple-areolar complex, and the muscle is draped over a breast implant to soften the texture and appearance of the reconstructed breast. The surgeon has the option of either placing an implant in the immediate setting or using a tissue expander with the flap with later exchange to an implant.
A latissimus dorsi flap combined with a breast implant is a good option for obese patients, in whom it is not always safe to perform a TRAM flap procedure (Fig. 8).20 It is also a good option for thin patients who are not candidates for a TRAM flap procedure because of inadequate tissue for reconstruction or for closure of the abdominal donor site. Unlike the tissue-expansion method, breast reconstruction with a latissimus dorsi flap plus an implant can create a ptotic-appearing breast. The skin island that often is included with a latissimus dorsi flap immediately can replace any resected skin, along with the nipple-areolar complex, to retain the initial shape of the breast skin envelope. Another benefit of latissimus dorsi flap-based reconstruction as opposed to tissue expansion is that a second surgical procedure is not necessarily required. The surgical time with unilateral reconstruction ranges from 3 hours to 6 hours. Although most patients require only a 2 to 3 day hospitalization, a longer recovery period (4 weeks) is required than with implant-only reconstruction. A disadvantage with latissimus dorsi flap-based reconstruction is that the latissimus muscle tends to atrophy over time, which makes the underlying breast implant more prominent and can reveal even subtle irregularities in the implant caused by capsular contracture.20
Breast reconstruction using the patient's own tissues results in the most natural-appearing reconstructed breasts
Although autologous tissue procedures can be lengthy and are associated with the longest recovery period, they often require fewer revision and symmetry procedures (i.e., to correct problems resulting from implant malposition secondary to capsular contracture).35 With autologous tissue reconstruction, it is possible to create a ptotic-appearing breast without the need for a breast implant, and the appearance of the contralateral native breast can be matched without the need for an additional contralateral symmetry procedure.33 In addition to aesthetic benefits, autologous tissue-based reconstruction offers extreme versatility in terms of providing extensive tissue replacement and providing a blood supply to assist with healing within an irradiated operative field.11 Although autologous tissue procedures require a donor site, with the potential for associated morbidity, they avoid implant-related problems, which can worsen over time.1
TRAM flaps: Arduous recovery, best aesthetic outcome
Although breast reconstruction with a TRAM flap can be ideal for motivated patients, it is associated with a long and arduous recovery that requires that patients have a good support system. Although some patients miss work for 4 to 6 weeks, many return to work within several weeks, particularly young patients with desk jobs. However, with TRAM flap reconstruction, patients often require fewer follow-up office visits than for tissue expansion and require fewer subsequent surgical procedures.
The fatty tissue of the TRAM flap resembles normal breast tissue and can result in a natural-appearing reconstructed breast. Breasts reconstructed with a TRAM flap also tend to adjust to changes in body weight.36 If a patient who undergoes an implant-based reconstruction has significant weight loss, then an implant exchange may be required to retain symmetry between the reconstructed breast and the normal breast. In a patient who has undergone a TRAM flap reconstruction, the reconstructed breast and the contralateral native breast tend to change in tandem in response to changes in body weight. A TRAM flap reconstruction also involves an abdominoplasty (tummy tuck), which patients always are excited about, because it allows them to focus on something positive in the midst of otherwise negative changes that are affecting their body image.
Obesity and smoking increase the risk of complications after TRAM flap reconstruction.30, 37 A body mass index <30 kg/m2 is preferred, and patients with a body mass index ≥35 kg/m2 are considered to be at high risk for complications. These complications are related mainly to a decreased blood supply to the TRAM flap (associated with an increased risk of fat necrosis) and wound-healing problems at the lower abdominal donor site. Although, with immediate TRAM flap reconstruction, it is not always possible to have patients quit smoking prior to surgery, with delayed TRAM flap reconstruction, it is prudent to insist that patients quit smoking prior to the procedure.
The blood supply to a TRAM flap can be provided by any of several methods. One method is to transfer the lower abdominal fatty tissue together with attached underlying rectus abdominis muscle. This type of flap is referred to as a pedicled TRAM flap. The blood supply originates from the internal mammary vessels in the thoracic region and travels through the rectus abdominis muscle as the superior epigastric vessels to the umbilical region, where the superior epigastric vessels become the deep inferior epigastric vessels and send perforating vessels into the lower abdominal skin and subcutaneous tissue. With a pedicled TRAM flap, there are limitations on the amount of lower abdominal tissue that can be transferred reliably because of an increased risk of fat necrosis within the TRAM flap. This issue can be especially problematic in obese patients and smokers. In an effort to provide a more robust blood supply to a pedicled TRAM flap, such as in the case of a patient with a high body mass index, a surgical delay (partial dissection with ligation of the inferior epigastric vessels) may be performed prior to the planned breast reconstruction. Pedicled TRAM flaps require that the entire rectus muscle be elevated and remain attached to the flap. Consequently, the inframammary fold must be disrupted to tunnel the flap to the chest wall, which tends to result in a bulge in that region.
Another method of transferring the lower abdominal fatty tissue (the method that we prefer at M. D. Anderson) is the microvascular TRAM flap procedure (Fig. 9). A microvascular TRAM flap is freed completely from the underlying rectus abdominis muscle, with its blood supply based inferiorly directly off the deep inferior epigastric vessels, which are branches of the iliac vessels, the predominant blood supply to this anatomic region. This approach avoids the need to use the entire rectus muscle to transfer the flap to the chest wall. At M. D. Anderson, we most commonly use the internal mammary vessels, which are located on the medial chest wall, as recipient vessels for the microvascular transfer. The internal mammary vessels provide several advantages over the thoracodorsal vessels, which were our previously preferred recipient vessels. In patients with breast cancer who undergo sentinel lymph node biopsy, the thoracodorsal vessels can be damaged, but the internal mammary vessels are not at risk.1 Use of the internal mammary vessels also allows for more medial positioning of the TRAM flap on the chest wall, which creates a more ideal shape of the reconstructed breast.38
After the microvascular TRAM flap is harvested, it is transferred to the chest wall and anastomosed to the internal mammary vessels, which are accessed by removal of the third intercostal cartilage. Removal of the cartilage usually does not cause pain or deformity.38 Occasionally, removal of the cartilage is not required, because large, perforating vessels from the internal mammary artery and vein perforate between the ribs and are of adequate caliber to serve as recipient vessels.
Microvascular TRAM flaps provide some advantages over pedicled TRAM flaps, including less disturbance of the abdominal wall donor site, a more robust blood supply, and the need for less rectus muscle, because the flap does not need to be tunneled to the chest wall.39 Decreased disturbance of the abdominal wall and the need for less muscle maybe beneficial for active patients and can avoid the need for synthetic mesh to support the abdominal wall and maintain its contour. Fatty tissue has a very tenuous blood supply, which can become especially evident when we transfer it as a flap. Fat necrosis within a breast that has been reconstructed with a TRAM flap can result in significant atrophy and contour deformities, which may cause asymmetry with the normal breast. The microvascular TRAM flap is supplied directly by the deep inferior epigastric system and not by a circuitous route that depends considerably on the number of choke vessel connections between the superior and inferior epigastric systems located within the umbilical region. The result is less fat necrosis within the microvascular TRAM flap,39 especially in patients who have thick abdominal pannus.30 The enhanced blood supply also allows for the use of a larger portion (75%) of the lower abdominal ellipse of a TRAM flap.
Although the microvascular TRAM flap procedure offers many benefits over the pedicled TRAM flap procedure, the microvascular procedure is more demanding technically and has an all-or-nothing result: If the anastomoses thrombose and the flap cannot be salvaged, then the TRAM flap is lost, and the patient needs another method of breast reconstruction.
Although many patients now present for their breast reconstruction consultation requesting a deep inferior epigastric perforator (DIEP) flap procedure, which comes from the same region as the TRAM flap, DIEP flaps are used best selectively, based on the specific needs of the patient (they may be appropriate for athletic patients, because the entire rectus abdominis muscle is preserved) and the ability to provide an adequate blood supply to the flap (blood supply is better when a relatively small volume of tissue is needed to reconstruct the breast and when the patient has only a thin or moderately thick lower abdominal pannus). Patients should have relatively large perforating blood vessels from the underlying deep inferior epigastric vessels, through the rectus muscle, into the lower abdominal skin and subcutaneous tissue. Unfortunately, it is not possible to predict reliably the caliber of these perforating vessels preoperatively; therefore, it may be prudent not to assure patients that DIEP flap reconstruction is possible.
The DIEP flap avoids the need to harvest any rectus muscle or abdominal fascia. However, DIEP flaps have been associated with a decreased blood supply compared with TRAM flaps and may result in an increased incidence of fat necrosis that can affect the shape and contour of the reconstructed breast significantly.40 Breast reconstruction with a DIEP flap is longer and even more technically demanding than microvascular TRAM flap reconstruction. Although the DIEP flap offers potential functional benefits with regard to the abdominal wall, from an aesthetic point of view, the results essentially are the same as those achieved with microvascular TRAM flap reconstruction (Fig. 10).
Another option for breast reconstruction using autologous tissue is a gluteal artery perforator (GAP) flap. The design of a GAP flap resembles that used for an aesthetic buttock lift, with the scar hidden within the bathing suit or underwear line. The flap includes only the skin and the subcutaneous tissue harvested based on the superior or inferior gluteal artery and vein with no gluteal muscle removed—fibers simply are split longitudinally to expose the vessels down to the bony pelvis. Most reconstructive surgeons consider gluteal flaps to be a second-line option for autologous breast reconstruction, usually reserved for patients who already have undergone a TRAM flap reconstruction for contralateral breast cancer, or who have undergone a previous aesthetic abdominoplasty, or who have very little abdominal subcutaneous tissue or no laxity in the abdominal musculofascial system (nulliparous women). In these circumstances, gluteal flaps also are useful when the patient has received prior radiotherapy to the chest wall, in which case, the use of breast implants is not a preferred option.
In summary, the complexity of planning for immediate breast reconstruction has increased as a result of the increasing use of axillary sentinel lymph node biopsy, the more frequent use of neoadjuvant chemotherapy, and the more aggressive use of PMRT, even in patients with early-stage breast cancer. These new developments necessitate a team approach with increased communication between the breast surgeon, medical oncologist, radiation oncologist, and plastic surgeon.