|Summary, conclusions and future perspectives
The aim of this thesis was to identify certain characteristics as risk factors that influence the outcome of some of the breast reconstruction techniques used by the plastic surgeons of the Netherlands Cancer Institute-Antoni van Leeuwenhoek hospital. The evaluated characteristics were either preoperatively existing patient- or disease-related characteristics, or procedure-related characteristics. As non-ablative surgeons, our primary interest was the identification of characteristics that complicated the outcome of reconstructive surgery. Still, whenever relevant, the oncological safety of our work was also considered.
The requirements and results of breast reconstruction are not primarily dictated by reconstructive possibilities but, rather, by oncologic requirements, possibilities, and results. In the first chapter, the influence of the evolution of oncologic breast cancer treatment on the evolution of reconstructive breast surgery and the outline of this thesis were presented. Currently, breast reconstruction after breast cancer treatment includes a wide variety of treatment strategies and techniques. These range from non-skin sparing to skin sparing techniques, from delayed to immediate reconstruction, and from prosthetic implantations to microsurgical transplantation of autologous tissues.
These techniques have all been shown by others not to interfere with oncological safety and to be psychologically and socially beneficial to women who need curative or prophylactic breast cancer treatment. Still, only 10% of women who undergo breast cancer treatment also undergo breast reconstruction and one of the tasks of reconstructive breast surgeons is to continue to increase the awareness of the possibility of reconstruction among these women and their oncologists. Likewise, an increase of facilities for reconstructions is needed.
Breast conserving therapy (BCT) is widely accepted as an appropriate method of primary treatment of T1 and T2 breast cancers that measure up to 5 cm. For safe and cosmetically acceptable BCT in patients with larger breast cancers, the tumor volume has to be reduced preoperatively and lost tissue volume ought to be replaced after wide local excision. In 1993, our group reported encouraging short-term results of a combination of preoperative radiotherapy, breast conserving surgery, and immediate tissue replacement by myo-(sub)cutaneous latissimus dorsi flap transplantation in patients with relatively large T2 and T3 breast cancers. To evaluate the long-term oncologic local control and cosmetic outcome of this treatment modality, we studied the results obtained in 20 patients after a minimum follow-up of 5 years.
The local control rate was 0.95 as loco-regional recurrence was observed in one patient who refused adjuvant chemotherapy. Both the observed 5-year survival (0.75) and the actuarial 10-year survival (0.60) in our series equaled that of more radical surgical therapy. The cosmetic outcome compared to that obtained by conventional BCT modalities for small breast cancers. In general, the patients’ assessment of cosmetic outcome (2.8 out of 3) was higher than the assessment of a professional panel (6.3 out of 10). Out of 6 criteria providing a detailed description of the cosmesis of the reconstructed breast and donor area, the symmetry and shape of the reconstructed breast were felt to be most important by patients and professionals alike. In chapter 2, we concluded that breast conserving therapy combining preoperative irradiation and immediate myo(sub)cutaneous latissimus dorsi flap reconstruction is an oncologically safe and cosmetically rewarding, but logistically straining modality of treatment of relatively large T2 and T3 breast cancers.
Combining and coordinating radiotherapy, ablative surgery, and immediate reconstructive surgery requires a well cooperating multidisciplinary approach to not compromise oncologic accuracy. Even in an optimally staffed and equipped oncologic institute like ours, this requirement proved to frustrate the definitive establishment of such a combination therapy. Because more recent treatment modalities of neo adjuvant chemotherapy offer a remission rate of up to 0.80, a combination of chemotherapy, ablative surgery, and immediate reconstruction may be applied to circumvent part of the logistic problem. The possible role of neo-adjuvant chemotherapy and the related logistic challenges are currently being explored in collaboration with the medical oncologists of the Netherlands Cancer Institute-Antoni van Leeuwenhoek hospital.
In 1986, the combined use of the lateral thoraco-dorsal (LTD) flap and an implant was introduced as an alternative method of delayed reconstruction of small- to medium-size breasts for postmastectomy patients who are reluctant or unable to consider reconstruction by tissue expansion or by more extensive autologous transplantations tissues. So far, the technique has only been proven reproducible in Sweden. Postmastectomy radiotherapy has been proven by Swedish researchers to increase the risk of wound healing complications after LTD transplantation, and advanced age, obesity, smoking, and some general health characteristics have been indicated as additional risk factors.
We initiated a prospective study to assess the reproducibility of this technique outside Sweden, as well as to confirm the proven risk factor, prove or refute the alleged ones, and possibly identify additional ones. Additionally, we applied the technique for immediate breast reconstruction and tried to expand the indications and applications of the LTD flap even further. In chapter 3, we reported on the experience with our first 60 LTD flaps and concluded that the lateral thoraco-dorsal flap is a well reproducible technique for breast reconstruction with few complications leading to failure. The LTD flap allows for reconstruction of breasts of larger than medium size by using it in combination with tissue expanders. Moreover, we successfully applied fully deepithelialized LTD flaps for additional indications. Statistical significance of the postmastectomy radiotherapy as a risk factor could not be confirmedbut we proved some general health characteristics to be significant patient-related risk factors. Out of 5 surgery-related characteristics, only an increased flap length was proven to negatively influence the outcome of surgery.
To date, it has never been recommended to limit the length of the LTD flap to 17 cm. Although not proven in our study, this limitation may only be relevant for patients in whom one of the other alleged risk factors is present. Still, we did not extend the flap over 17 cm in approximately 100 subsequently transposed LTD flaps. Furthermore, we adjusted the flap design to advance its pivot point medially. This way, this point more closely resembles the future nipple-areolar complex and better use seems to be made of the full extent of the flap. By restriction of the donor site to the area immediately lateral to the inframammary fold, the donor scar will be covered by the bra. The possible benefits of these modifications need to be assessed in future studies.
In addition to the alternative indications of the LTD flap presented in chapter 3, this flap may also be used as a salvage procedure for partial loss of autologous flaps used in breast reconstruction. The transverse rectus abdominis musculocutaneous flap or deep inferior epigastric perforator flap are the flaps of choice for autologous breast reconstruction. The better understanding of the vascular anatomy of these flaps has reduced the incidence of flap loss and fat necrosis and positioning the flap’s least vascularized zone laterally in the newly reconstructed breast may limit partial flap loss to that area. Still, the resulting defect of such partial loss remains a challenge.
We introduce the use of the lateral thoraco-dorsal flap as an easy and straightforward salvage procedure in such cases and present the history of 4 of our patients with a mean age of 45 years to illustrate this use. We concluded that the procedure might be executed as early as 6 weeks after initial reconstruction, reducing the burden of daily wound care for the patient and offering her an immediate restoration of the lateral contour of the reconstructed breast.
Combined skin sparing mastectomy and immediate reconstruction by use of an implant is increasingly accepted as a therapy for patients with breast cancer or a hereditary risk of breast cancer. Because little and contradictory evidence regarding possible risk factors for postoperative complications is available, we retrospectively assessed 13 such risk factors. Additionally, we evaluated the oncological safety of the procedure. From July 1996 through June 2000, 174 skin sparing mastectomies were combined with immediate breast reconstruction in 120 patients. We assessed the influence of 5 patient-related and 8 breast-related characteristics on the incidence of a complicated postoperative course by univariate and multivariate analysis. Oncological safety was evaluated by observed recurrent disease and 5-year survival.
Severe complications were observed in 17 patients of the 120 patients (14%), or 19 of the 174 breasts (11%). The patient-related characteristics age and being operated unilaterally yielded significantly increased the risk of complications. Resident plastic surgeons and previous breast conserving therapy including radiotherapy significantly increased the risk of loss of implant. No breast cancer or related disease was observed in patients who underwent prophylactic mastectomy. Local relapse rate among patients operated for cancer was 0.02. The actuarial 5-year survival rate among patients who underwent curative mastectomies was 0.96.In chapter 5, we concluded that combined skin sparing mastectomy and immediate reconstruction by use of an implant is oncologically safe but the risk of postoperative complications cannot be neglected.
Our complication rate of 33% and loss of implant in 14% may well reflect our liberal inclusion of all patients who asked for reconstruction even though they knew they ran an increased risk as a result of known or alleged risk factors. Our observations and those by others on these potential risk factors may offer guidance to adapt indication and treatment strategies for patients with breast cancer or increased hereditary risk of such cancer. Still, a prospective study was needed to assess the importance of these risk factors as clinically relevant selection criteria to distinguish favorable candidates for immediate breast reconstruction.
Historically, the incision used for the mastectomy evolved from an oblique vertical to a horizontal orientation to facilitate the resection of breast tissue and the approach of the axillary lymph nodes. In the multidisciplinary approach of breast cancer treatment, this incision was adapted for cosmetic reasons without compromising the oncological safety. Consequently, a peri-areolar incision has been added by a curved caudal extension, since April 2000. Because the origin of the pectoralis major muscle is dissected to further improve the cosmesis of the reconstructed breast, the implant is in immediate contact with the subcutaneous tissue of the skin wound. To prevent possible contamination of the implant in case of wound healing problems, we simultaneously introduced double-breasted closure of the skin wound.
Double-breasted closure of the skin is achieved by deepithelialization of one edge of a wound and advancement of the opposite edge over this deepithelialized area. Such closure may prevent contamination or exposure of the implant in cases where immediate breast reconstruction with prosthetic material is obtained after skin sparing mastectomy. The deepithelialization routinely extends as far as the incision to be closed and, consequently, the skin suture at the end of the incision immediately overlies the deep suture or implant in cases where the implant is not fully covered by muscle. To prevent contamination or exposure of the implant when suture infection or wound dehiscence in these cases, we extend the deepithelialization beyond and around the limit of the skin incision. This allows for complete and secured double-breasted closure of the entire wound and lessens the risk of implant contamination or exposure.
Our preliminary results in the first 350 breasts operated this way indicated that extended double-breasted skin closure immediately over the implant, in terms of postoperative complications and surgical outcome, is comparable to direct skin closure over the pectoralis major muscle overlying the implant. In chapter 6, we concluded that the advantages of extended double-breasted closure are the more favorable projection of the lower pole of the reconstructed breast and the restriction of the mastectomy scar to its inferio-lateral aspect. We have used this technique for most of the patients included for the prospective study presented in chapter 7.
The complication rate after skin sparing mastectomy and immediate breast reconstruction is reported to be 5% to even 35%. Although attempts have been made to identify the risk factors leading to complications after combined skin sparing mastectomy and immediate prosthetic breast reconstruction, hardly any criteria are available to preoperatively distinguish patients in whom such an eventful postoperative course may be expected. Therefore, we wanted to establish which factors increase the risk of surgical complications to such a level as to adjust our indications of immediate breast reconstruction after skin sparing mastectomy. We prospectively studied the clinical relevance of 6 patient-related and 9 procedure-related characteristics as potential risk factors for a complicated surgical outcome in 400 such combined procedures by univariate and multivariate logistic regression analysis. Risk factors that proved significantly correlated with loss of implant by both analyses were accepted as clinical selection criteria that distinguish potential candidates with an unacceptably high risk of such loss.
The overall complication rate was 33% and the rate of loss of the implant 18%. Mild complications occurred significantly more often in patients who were older than the mean age of 43 year, and in breasts that were more than averagely sized or were operated by a fellow in oncologic surgery. Implants were significantly more often lost in patients who were obese or smoked, and in breasts that were more than averagely sized. In chapter 7, we concluded that the clinically relevant increase of risk of implant loss should lead to reluctance to perform combined skin sparing mastectomy and immediate prosthetic breast reconstruction in obese patients who smoke (32% loss), and in those with more than average sized breasts (27% loss).
Our liberal acceptance of patients referred for immediate breast reconstruction led to a high complication rate. If we had excluded all patients in accordance to the now proven relevant selection criteria, our complication rate would have been 6.3%. Still, such strict application of selection criteria disfavors part of the excluded patients as statistics only reflect relative risks. Therefore, we feel that it is more important to preoperatively discuss these relative risks with our patients to come to a choice of treatment. Our observations allow us to do so more accurately.
Over the years, we had all scars of previous oncologic breast surgery that were excised during subsequent reconstructive procedures histologically examined for de novo tumors or metastases. Such routine histological examination of secondarily excised mastectomy scars is considered good practice even though the microscopic detection of a metastasis in clinically unsuspected mastectomy scars is rare. Because cost-effective use of histological services is required, the occurrence rate of metastases in such scars needed to be established to assess the possible benefit of such routine examination.
The histological observations on 728 clinically unsuspected scars from prophylactic (n = 151) or curative (n = 395) mastectomy or breast conservation treatment as performed over the last 10 years in 424 patients, were traced and correlated to the indication of initial breast surgery, possible adjuvant therapy, and time lapse between initial surgery and scar examination. In none of the 728 scars, a scar metastasis or de novo tumor was found. In chapter 8, we concluded that routine histological examination of clinically unsuspected scars excised at the time of breast reconstruction or scar correction after prophylactic or curative breast surgery did not benefit our patients. Consequently, we no longer routinely submit such scars for histological examination.
In all, breast reconstruction is one part of the multi-disciplinary spectrum of care to be offered to a woman with breast cancer or a hereditary risk thereof. Such a medical, paramedical, and even non-medical multi-disciplinary approach may provide her with a feeling of being understood and being taken care of in every aspect of her (potential) disease and its treatment. We assume that her quality of life is the result of a complex interaction of outcome of disease, coping behavior, social support, and the quality of care received. Breast reconstruction can enhance this quality of life.
Still, breast reconstruction has its surgical risk-factors and complications. Instead of easing the emotional pain over the loss of a breast, these complications can make breast cancer treatment even more traumatic. The chance of increase of emotional trauma needs to be considered preoperatively with the patient. Only a properly and honestly informed patient can make a decision on her treatment and cope with its possible risks and disadvantages. To properly inform the patient, the severity and occurrence rate of an uneventful outcome of treatment needs to be known. We tried to establish these aspects in the studies presented in this thesis. Still, more studies are needed to allow for true evidence-based practice.
Establishing an evidence base is difficult in the field of plastic and reconstructive surgery because indications, expectations, surgical skills and preferences, and outcome assessments have a very subjective nature. Many of the reports studied for this thesis described surgical methods or opinions without offering an objective rationale. Other reports were limited by small numbers of studied patients or by insufficient statistical power to detect significant results. We are privileged to execute our research in an oncological institute, which allows for large numbers of patients to be included in our studies. Hence, we were able to initiate an evaluation of our reconstructive results based on objective parameters, rather than ‘author’s opinions’. Further research needs to be done to more objectively clarify these, and additional, aspects of reconstructive breast surgery and to render a true base of evidence.