Current Opinion in Gynecology and Obstetrics Technique of Breast Reconstruction with Expander Implants after Mastectomy

The reconstruction of the female breast after mastectomy is an integral part of the surgical treatment of breast cancer nowadays. If it is necessary for oncologic reasons and if there are contraindications for breast conserving therapy, methods of breast reconstruction can contribute significantly to the restoration of physical integrity, including an improvement of life quality for the affected women. Besides an improvement or restoration of the physical image and of the self-esteem, breast reconstruction leads to a processing of an oncologically necessary mastectomy from a psychooncological and rehabilitative point of view. Alloplastic methods of breast reconstruction are the most common methods of reconstructing the female breast after mastectomy. In order to obtain optimal results from reconstruction, the use of textured, anatomically shaped expander-implant systems are recommended. After modified radical mastectomy a combined expander-implant reconstruction can be indicated to reconstruct a smaller, non-ptotic breast after preforming stretching of the skin. This combined expander-implant reconstruction can be performed primarily during mastectomy as well as secondarily. If adjuvant therapy is necessary, especially in the case of radiation therapy, an implant or expander-implant reconstruction is relatively contraindicated because of an insufficiently high rate of complication. The patients need to be informed about the very often necessity of adapting mastopexy or reduction mastopexy of the contralateral breast and about possible autologous methods of reconstruction. In our opinion, adjuvant radiation therapy is a contraindication for alloplastic reconstruction because of an inacceptable complication rate, especially if compared to autologous reconstruction. Therefore, primary alloplastic reconstruction should be indicated very critically. When planning alloplastic or, of course, autologous breast reconstruction the overall oncological situation of the patient needs to be considered. To avoid prognostic or aesthetic disadvantages, the differential indication for the methods of breast reconstruction should ideally take place in specialized breast centres with experience in all methods of reconstruction.


Introduction
The reconstruction of the female breast after mastectomy is an integral part of the surgical treatment of breast cancer nowadays [1,2].If it is necessary for oncologic reasons and if there are contraindications for breast conserving therapy, methods of breast reconstruction can contribute significantly to the restoration of physical integrity, including an improvement of life quality for the affected women.Besides an improvement or restoration of the physical image and of the self-esteem, breast reconstruction leads to a processing of an oncologically necessary mastectomy from a psychooncological and rehabilitative point of view [3].

Development of expander and implant technology
The era of modern breast reconstruction started in the early 60s of the last century with the introduction of silicone-filled implants.Implants of the old generation have a round shape and a smooth surface.Smooth implants tend to have an increased rate of intense capsular contractions, dislocations and therefore often a bad, asymmetric overall result with a frequent need of correcting surgery such as capsulotomy, capsulectomy, change of implant, explantation surgery and autologous conversion.Furthermore, implants with a round shape are suitable only for a small breast up to 300 g without contralateral ptosis and little projection, a type of breast that is to be found in Asia mainly [4,5].
Implants of the new generation which are in use these days reflect the developments of implant technology of the last years and lead, provided that the medical indications are respected, to very good symmetric reconstructions with long term stability of the results.By texturising the surface of the implant the rate of capsular contractions and the need for correcting surgery declined significantly.
If surfacing the implant with polyurethrane leads to the same long term results cannot be finally judged yet.In conditions of thin soft tissue, the combining of polyurethrane surfacing and surrounding tissue can cause surgical difficulties in case of a necessary change of implants or it can be a contraindication for reimplanting.The filling of the implants with cohesive silicone gel in combination with an enforced coat of the implant lead to significantly higher safety of the implants.Because of their fluid consistency and instability of their form implants with sodium chloride filling can only be recommended limitedly in regard of the aesthetic overall result.The decisive progress in alloplastic breast reconstruction is based on the development and introduction of anatomically shaped implants.This shape of implants facilitates the reconstruction of a natural, symmetrical breast as it is found in Europe and America [6,7].
In the 1970s Radovan introduced the expander technology in breast reconstruction [8].Various progresses in design and technology of expanders lead to more consistent and better results in expansion and therefore made alloplastic breast reconstruction more predictable and safer [9].Texturising of the surface of the expanders simplifies the process of expansion, leads to less capsular contractures (especially in combination with textured implants), dislocation and deformation of the chest wall.The introduction of anatomically shaped expanders enables the expansion of the lower breast pole, which is preferred in most cases, in order to prepare a symmetrical reconstruction.By integrating a valve directly in to the expander the placement of a distant port for filling is unnecessary and increases the comfort for patients and doctors during the expansion phase.
According to our experience, the best results of alloplastic breast reconstruction are achieved by the use of anatomically shaped, textured implants filled with cohesive gel and, in case of need of tissue expansion, in combination with anatomically shaped, textured expanders (Figure 1) [2,10].

Figure 1: Expander reconstruction
The preoperative marking of the subpectoral expander-implant loge is performed on the chest wall and can be supported by so-called "templates".The lower line of the loge should not be more than 1 cm below the inframammary crease.The submuscular, in the caudolateral area subcutaneous loge should have the same extent as the chosen expander and should correspond to the basis and height of the contralateral breast.

Basics of alloplastic breast reconstruction
In order to achieve optimal cosmetic results of alloplastic breast reconstruction, these anatomic conditions need to be respected [11,12]: 1. Conservation of the inframammary crease 2. Integrity of the major pectoral muscle 3. Quality and tautness of the skin The conservation of the inframammary crease during mastectomy is safe from an oncologic point of view, as only very rarely is there breast parenchyma to be found distal to the inframammary crease.The inframammary crease is formed by fusion of the superficial and the mammary fascia.Its contour is defined by the distribution of fine fibrous retinaculae which connect the dermal as well as the musculofascial layers to a superficial fascia.The mammary fascia represents the natural cover of the mammary gland.The loss of this structural network at the time of mastectomy will lead to an inferior cosmetic result.
Small lesions of the major pectoral muscle present no problem for an alloplastic breast reconstruction.However, larger dehiscences within the muscle should be provided with absorbable sutures.Alloplastic breast reconstruction is planned geometrically according to three parameters: width of the breast (basis of the breast), height of the breast and projection.The width and the height are defined by the measurements of the contralateral breast.They are then plotted on the side of the chest wall that is to be reconstructed precisely to where the planned localization of the expander is.
The projection of the breast can to some extent be predicted by the dimensions of the expander.Depending on the final volume, a permanent anatomic implant with corresponding width, height and projection can be chosen [13].

Indications for alloplastic breast reconstruction
Relative contraindications: Because of a higher overall complication rate in primary expanderimplant reconstruction, secondary expander-implant reconstruction should be preferred if alloplastic reconstruction is indicated.For reconstruction of a smaller, non-ptotic breast after mastectomy without radiation of the chest wall secondary expander-implant reconstruction is suitable to achieve a good cosmetic result, provided that a subtle planning and surgical technique is considered [14][15][16].
Secondary combined expander-implant reconstruction is the most commonly used method of reconstruction of the female breast after mastectomy these days.If performed with the most modern expander and implant technologies this method has various advantages [17]: 1.It is a relatively simple and safe surgical technique which is easy to be taught, understood and standardized, and thus also suitable for less highly specialized centers.2. Only tissue of identical texture, colour and sensitivity is used for breast reconstruction.3.As compared to autologue reconstruction with distant flaps there is no morbidity in the area of extraction.4.Only a small incision with consequently little scarring is necessary.5.The operation time is significantly reduced as compared to autologue reconstruction.The time of postoperative reconvalescence is short.
Generally speaking, a small, not ptotic contralateral breast is suitable for alloplastic breast reconstruction after mastectomy.Patients need to be informed that, in order to adjust symmetry or shape, mastopexy or reduction mastopexy might be necessary.The risk of a secondary, adapting reduction mastopexy increases with size and ptosis of the contralateral breast.
Macromasty and extreme ptosis of the contralateral breast are relative contradindications for a reconstruction with expander-implant.The most important relative contraindication, however, is radiotherapy of the chest wall [18][19][20][21].Since the indication for radiation of the chest wall has been extended in the last years, and primarily depends on histopathologic parameters (tumour size, lymphangiosis, lymph node metastases), the indication for primary reconstruction with implant or expanderimplant has to be very restricted and well-considered.After radiation therapy, fibrosis and interactions with the blood circulation of the skin increase the rate of complications in alloplastic reconstructions such as capsular contractures, necrosis or deficient aesthetic results.The eschewal of expander reconstruction is very often possible in skin-sparing mastectomy (SSM).Especially in cases of extended ductal carcinoma in situ, SSM is an increasingly common surgical alternative to modified radical mastectomy [22].

Information to patients: It is very important to
inform patients thoroughly about general methods of breast reconstruction.It is necessary to inform about advantages and disadvantages of alloplastic reconstruction as compared to autologous reconstruction including microsurgical techniques (deep inferior epigastric perforator = DIEP flaps).When indicating alloplastic reconstruction, the wish of the patient to be intensely informed needs to be respected.Former surgery, age and comorbidity of the patients, previous or postoperative radiation therapy, size of the breast, shape of the breast, symmetry, the personal experience of the surgeon and, last but not least, the wish of the patients are essential parameters when choosing the optimal method of breast reconstruction [1,23].
Surgical procedure planning: When planning the surgical procedure, the incision line and the amount of skin that needs to be removed have to be considered from an oncological as well as a plastic-reconstructive point of view, already at the time of mastectomy.The dimension of the contralateral breast, especially the basis of the breast, defines the size of the expander.The preoperative marking of the subpectoral expanderimplant loge is performed on the chest wall and can be supported by so-called "templates".The lower line of the loge should not be more than 1 cm below the inframammary crease.The submuscular, in the caudolateral area subcutaneous loge should have the same extent as the chosen expander and should correspond to the basis and height of the contralateral breast.During the preparation of the submuscular loge, a consistent dissection is performed visually in cranial, caudal and medial direction.The caudal and medial insertions of the major pectoral muscle are cut through visually, coming from the subpectoral direction (Figure 2).The expander loge in the caudolateral area of the chest wall lies subcutaneously.This is especially important for secondary expander-implant reconstruction.When implanted in the loge, the expander is filled to 50% with a sodium chloride solution.Afterwards, the wound is closed layer by layer.The closing of the major pectoral muscle is especially important in order to achieve a sufficient coverage of the expander with soft tissue (Figure 3).
The further expansion starts one week after implantation in intervals of 3 days, in steps of 50 to 100 ml.Rapid expansion is necessary to avoid early development of a capsula.
The filling volume should be at least 70-80% of the possible expander volume.After another three to six months, the expander can be replaced by a suitably planned and chosen implant.Form and size of the chosen implant determine the quality of the result of the reconstruction.The implant loge can be optimized by targeted capsulotomy.If the inframammary crease is too high, it can be lowered by caudal capsulotomy.If the inframammary crease is too low, it can be reshaped and relocated by caudal capsulotomy, ellipsoid capsulectomy and adaptation of the anterior to the posterior capsula with non-resorbable sutures.After insertion of a drain, the final anatomic implant is put in and the wound is closed in multiple layers.The positioning of the implant over the first two postoperative weeks is ensured by a special tape bandage [24,25].During the preparation of the submuscular loge, a consistent dissection is performed visually in cranial, caudal and medial direction.The caudal and medial insertions of the Pectoralis major muscle are cut through visually, coming from the subpectoral direction.The expander loge in the caudolateral area of the chest wall lies subcutaneously.This is especially important for secondary expander-implant reconstruction.When implanted in the loge, the expander is filled to 50% with a sodium chloride solution.Afterwards, the wound is closed layer by layer.The closing of the major pectoral muscle is especially important in order to achieve a sufficient coverage of the expander with soft tissue.

Complications
The incidence of local complications is lower in primary implant and secondary expander-implant reconstruction than in autologous secondary reconstructions if the medical indications are respected [26,27].Early complications include haematoma, necrosis of the skin, infections and pain.Adjuvant treatments including chemotherapy and radiation therapy can cause delayed wound healing.Delayed complications are infection, implant extrusion and capsular contracture.Generally speaking, complications are more common after immediate reconstruction than after secondary reconstruction.This can be explained by the application of adjuvant therapies at the time of immediate reconstruction.Chemotherapy affects the immune system, and therefore influences processes of regeneration and wound healing.Radiation therapy deteriorates the capacity of skin stretching and leads to excessive fibrosis.Furthermore, it reduces oxygenation of the tissue, which leads to excessive capsular reactions.Persistent infections often lead to removal of the implants.In this case, further reconstructive procedures can only be performed after the final healing of the infections [28].

Conclusions
Alloplastic methods of breast reconstruction are the most common methods of reconstructing the female breast after mastectomy.In order to obtain optimal results from reconstruction, the use of textured, anatomically shaped expander-implant systems are recommended.After modified radical mastectomy a combined expander-implant reconstruction can be indicated to reconstruct a smaller, non-ptotic breast after preforming stretching of the skin.This combined expander-implant reconstruction can be performed primarily during mastectomy as well as secondarily.If adjuvant therapy is necessary, especially in the case of radiation therapy, an implant or expander-implant reconstruction is relatively contraindicated because of an insufficiently high rate of complication.The patients need to be informed about the very often necessity of adapting mastopexy or reduction mastopexy of the contralateral breast and about possible autologous methods of reconstruction.In our opinion, adjuvant radiation therapy is a contraindication for alloplastic reconstruction because of an inacceptable complication rate, especially if compared to autologous reconstruction.Therefore, primary alloplastic reconstruction should be indicated very critically.When planning alloplastic or, of course, autologous breast reconstruction the overall oncological situation of the patient needs to be considered.To avoid prognostic or aesthetic disadvantages, the differential indication for the methods of breast reconstruction should ideally take place in specialized breast centres with experience in all methods of reconstruction.

Figure 3 :
Figure 3: Expander reconstruction.This figure demonstrates the postoperative result of a secondary two stage reconstruction with a very nice shape of the reconstructed breast.