Chest wall resection and reconstruction for locally recurrent breast cancer: an experience of ve cases over a ve-Year period and literature review

Background: Expanded local resection is suitable for recurrent breast cancer patients who have isolated local lesion and have not metastasized. The extend of chest wall resection must be overall radical resection of the tumors diagnosed by pathology. However, surgery often leads to huge defects, even full-thickness defects, and these defects are dicult to repair. Here, we reported our experience in chest wall resection and reconstruction of patients with locally recurrent breast cancer, and also did a comprehensive literature review. Case Presentation: We report ve cases with locally recurrent breast cancer, followed by chest wall reconstruction with a pedicled rectus abdominis musculocutaneous ap or a pedicled latissimus dorsi musculocutaneous ap and, if necessary, a piece of titanium mesh. Chest wall resection and reconstruction were successfully achieved in all 5 patients. No complication and recurrence were observed, except one patient died of late lymphatic metastasis. Other patients reported good quality of life. Conclusion: For locally recurrent breast cancer, complete tumor resection is essential and ensures no recurrence. Appropriate material and the blood-rich ap or myocutaneous ap should be used to reconstruct the chest wall defect as an effective treatment for surgical procedure.

Case Presentation: We report ve cases with locally recurrent breast cancer, followed by chest wall reconstruction with a pedicled rectus abdominis musculocutaneous ap or a pedicled latissimus dorsi musculocutaneous ap and, if necessary, a piece of titanium mesh. Chest wall resection and reconstruction were successfully achieved in all 5 patients. No complication and recurrence were observed, except one patient died of late lymphatic metastasis. Other patients reported good quality of life.
Conclusion: For locally recurrent breast cancer, complete tumor resection is essential and ensures no recurrence. Appropriate material and the blood-rich ap or myocutaneous ap should be used to reconstruct the chest wall defect as an effective treatment for surgical procedure.

Background
Comprehensive therapy of breast cancer, including surgical excision, radiotherapy, chemotherapy, endocrinotherapy, and a combination of above approaches, is increasing bene cial for prolonging life [1][2][3]. However, it is sometimes di cult to avoid tumor recurrence. Although the main goal of chest wall resection is to achieve local tumor control, it may lead to long-term remission [4]. For primary breast cancer, an expanded radical resection is not required. However, regardless of the adjuvant therapy, expanded surgical excision is the essential procedure for the treatment of locally recurrent breast cancer. Repairing huge chest wall defects, especially full-thickness defects, is very di cult. If it is not repaired in time, it will not only damage the internal organs of the thorax, but also cause pathophysiological changes, such as chest wall softening, abnormal breathing and longitudinal swing, which will seriously affect the patient's respiratory cycle function [5]. Furthermore, locally advanced primary breast cancer and radiotherapy following a mastectomy are associated with chest wall defects. Therefore, chest wall resection is an important and essential procedure for the treatment of locally recurrent breast cancer, but ideal reconstruction is a guarantee to completely expanded resection.
It has been reported that chest wall resection has many surgical procedures [6-9], and is usually followed by reconstruction [3]. The purpose of reconstruction of chest wall is to restore the continuity of the chest wall structure, protect the thoracic organs, maintain the normal respiratory cycle function, and at the same time obtain a good thoracic shape, including chest wall bone reconstruction. Chest wall bone reconstruction used titanium mesh to stabilize the chest wall, local skin aps to cover soft tissue, pedicled musculocutaneous aps or free musculocutaneous aps to cover the chest wall [10][11][12]. Titanium micromesh reconstruction of the chest wall has the following advantages: tough texture, good shape, simple surgical method, good biocompatibility, and no need to place subcutaneous drainage. This is because that the subcutaneous exudate can be discharged into the chest tube through meshes of the titanium mesh [13].
Herein, we reported our experience in chest wall resection and reconstruction of patients with locally recurrent breast cancer using a pedicled latissimus dorsi musculocutaneous ap or a pedicled rectus abdominis musculocutaneous ap, and a piece of titanium mesh if necessary. Also, the literature about the therapy of locally recurrent breast cancer, and the reconstruction of chest wall resection was reviewed comprehensively.

Case Presentation
Typical case A 57-year-old female patient underwent radical mastectomy in 1995. However, the wound did not heal, and gradually became larger and worse. Even worse, she developed local ductal-invasive carcinoma recurrence (Fig. 1A).
Resection of the lesion: in December 2012, expanded local resection was performed according to pathologic demonstration, and the left chest wall defect was approximately 20 cm×15 cm (Fig. 1B). The full-thickness defect was from the second to fth ribs, about 12 cm×10 cm. The heart and lung were all exposed.
Reconstruction of chest wall defect: A piece of titanium micromesh was used to stabilize the thoracic cage defect (Fig. 1C). Thereafter, the defect was further reduced to 17 cm×14 cm, which was larger than 15 cm×13 cm of preoperative estimation. It was considered that the pedicled rectus abdominis musculocutaneous ap was the best reconstruction option. This is because that in addition to epigastric vessels, Doppler ultrasound cannot detect adjacent vessels that may contribute to reparation. The ap turned up 180° towards the defect through the subcutaneous space without tension ( Fig. 1D). Thoracic surgeon completed closed thoracic drainage.
Repair of abdominal defect: The pedicled aponeurosis ap of obliquus externus abdominis was about 10 cm×5 cm, sutured with the white line below the arcuate line and the free edge of the anterior sheath of the rectus abdominis. The abdominal wall was then repaired and reinforced with a piece of e-PTFE about 8 cm×6 cm (Fig. 1E). An incision about 10 cm long was made on the left umbilical level to form a rotation and advancement ap, which was then sutured with an advancement ap formed by the residual tissue of the right abdomen.
The patient left hospital 7 days after operation. The postoperative procedure was uneventful without any complication, such as paradoxical respiration, abdominal hernia, ap necrosis, wound infection, and so on (Fig. 1F). In addition, no signs of recurrence were found during the 5-year follow-up period (Fig. 1G,H).
In four years, a total of ve patients with locally recurrent breast cancer were treated in our department (Table 1). There were 3 cases of ductal-invasive carcinoma, 1 case of metaplastic carcinoma, and 1 case of malignant phyllodes tumor.
All patients' tumors were removed completely under the microscope. Four patients underwent the plastic reconstruction with a pedicled latissimus dorsi musculocutaneous ap, and the other underwent the plastic reconstruction with a pedicled rectus abdominis musculocutaneous ap. In addition, two patients underwent costectomy using a piece of titanium mesh to stabilize the chest walls were. The chest tubes were removed 3 and 8 days after surgery, respectively. Under prophylactic antibiotic treatment, all wounds showed a pattern of physiologic healing. There are no postoperative complications, such as ap necrosis, haematoma or seroma, herniation, local infection, hemia, respiratory failure, and pleural effusion.

Discussion And Conclusions
Therapy for locally recurrent breast cancer Approximately 30% of patients experienced recurrence of breast cancer, but most patients with metastases may lose their chance of surgery [14]. The incidence of locally recurrent breast cancer was 4% (2-20%), and can occur as an isolated cancer or in combination with distant metastasis in other organ systems [15]. That's why we reported a small number of surgical cases within 5 years. Whenever possible, isolated local recurrence should be treated with a curative intent. If feasible, it was recommended to pathologically con rm the margin of negative tissue and completely remove the recurrent tumor [16]. The resection area must contain at least 2 cm of normal tissue around lesion [17,18]. Then, the chest wall defect coverage should be performed immediately instead of breast reconstruction. This was due to limited tissue, limited surgical tolerance, and poor patient willingness to perform breast reconstruction immediately. Adjuvant treatments for recurrent breast cancer were radiotherapy, endocrine therapy in patients with estrogen or progesterone receptor-positive cancer, and chemotherapy in patients with receptor-negative cancer [19][20][21].

Reconstruction Materials for the chest wall bone
Local recurrence of breast cancer in the deep chest wall will lead to thoracic defects after surgery. If the diameter of fullthickness defect was greater than 6 cm, or if there were more than three defected ribs, especially in the anterior and lateral chest wall, it is recommended to reconstruct the chest wall bone in order to maintain proper cardio-pulmonary function [22]. Ideally, materials used for chest wall reconstruction should have good tensile strength, elasticity, stable physical and chemical properties, ease of use, ready availability, and high biocompatibility as well as characteristics that do not affect chest inspections [23]. Various materials for chest wall reconstruction were classi ed into autologous tissue, allogeneic tissue, and arti cial materials [24][25][26][27].
Although autologous tissue and allogeneic tissue are considered to be the most suitable repair materials for human physiology, the disadvantages of autologous and allogeneic tissues are limited materials, increased trauma, increased di culty in surgery, poor satisfaction in shaping, poor aesthetics, and insu cient hardness. These disadvantages often lead to postoperative abnormal breathing, thus it is more suitable for smaller defect repair and di cult to repair larger defect area, especially in the case of local infection or radioactive necrosis. Compared with autologous tissue, arti cial materials have better bone support for the chest wall, simplifying the operation process, shortening the operation time, and reducing the surgical trauma. Therefore, for larger chest wall defects, arti cial materials are currently the preferred materials for bone reconstruction [28].
Although many arti cial repair materials were used clinically, none of them can meet all the above requirements at the same time. Polytetra uoroethylene (PTFE) patch may injury intrathoracic organs due to thermal reaction. Insu cient rigidity of repair materials such as Marlex mesh, Prolene mesh, Vicryl mesh, Gare-Tex patch may cause abnormal breathing. Autologous tissue and allogeneic tissue are not suitable for bone reconstruction of large chest wall defects.
Moreover, titanium mesh has become a better option, originally created for craniofacial reconstruction [29,30]. Thus, we applied titanium mesh to stabilize the chest wall in two cases because titanium mesh has the following characteristics: rigid enough to prevent paradoxical respiration movement; malleability can be shaped into appropriate shape, inertness can avoid immune rejection, radiolucency can be used for radiographic tracking of potential problems, and porosity can allow in-growth of brous tissue [31]. Although it affects X-ray inspection, CT and MRI are now more common and accurate for chest examination. Therefore, we recommend titanium mesh for bone reconstruction of large chest wall defects (Fig. 1G,H).

Selection of aps for the chest wall reconstruction
As a prerequisite for stabilizing the chest wall, care should be taken to cover the soft tissue coverage, not only to cover the arti cial material that reconstructs the chest wall, but also restore the integrity of the chest wall, maintain the function of normal breathing and circulation, and improve the appearance and quality of life of the patients [11,12]. The soft tissue characteristics of recurrent breast cancer are often quite different from those of the primary cancer. There may be no donor vessels in the lesion available for free aps because of resection and radiotherapy. Meantime, for recurrent breast cancer patients, the simpler the surgery, the less invasive. Hence, free aps are not preferred. Especially for closure of large defects, they are not the rst choice for increasing the time of surgery and the incidence of complications. In addition to the local ap, the pedicle ap, or both aps fail to repair [32,33]. Myocutaneous aps are more suitable for the repair of breast cancer patients [33].
The selection of aps depends primarily on the location and area of the defect. On the vertical axis, the latissimus dorsi musculocutaneous ap and the pectoralis major myocutaneous aps are generally recommended for use in the upper 1/3 of the chest wall. It is recommended to use the latissimus dorsi musculocutaneous ap, rectus abdominis myocutaneous ap, pectoralis major myocutaneous ap, and omentum in the middle 1/3 of the chest wall. For the lower 1/3 of chest wall, it is recommended to use the rectus abdominis myocutaneous ap and omentum ap. On the horizontal axis, if the defect is located in the center of the chest wall, the latissimus dorsi musculocutaneous ap [34], the rectus abdominis myocutaneous ap [35] and the pectoralis major myocutaneous ap [36,37] can be repaired. In addition, in the lateral chest wall, the latissimus dorsi musculocutaneous ap is more commonly used.
However, the pectoralis major is usually resected in the locally recurrent breast cancer patients. Although the omentum ap has abundant blood supply, strong anti-infection ability, and strong plasticity, there is still a high risk of complicated operation, prolonged operation time, hemorrhage, abdominal hernia, and gastrointestinal complications after surgery. This is why they are not the rst choice for repairing chest wall defects. Although the latissimus dorsi myocutaneous ap may affect the ability of arm to lift, and the rectus abdominis myocutaneous ap may cause a weakness of the abdominal wall, they are still recommended as we did [1,2,10,11]. In addition, they not only provide enough volume to cover a large soft tissue defect, but also are simple to operate and can achieve good outcome.
Radical mastectomy and subsequent radiation may result in the loss of many important tissues, such as vessels, which may result in some of those aps being unstable for reconstruction as the above typical patient. Therefore, it is an important process to detect adjacent vessels by Doppler ultrasound before the operation.
In summary, for locally recurrent breast cancer, complete tumor resection is a crucial step and ensures that there is no recurrence. After surgery, the appropriate material should be selected to reconstruct the chest wall to restore the integrity of the thorax. Finally, according to the location and size of the defect, the blood-rich ap or myocutaneous ap is used to cover the wound, eliminate the dead space, and repair the soft tissue defect of the chest wall. Our therapy in chest wall resection and reconstruction of patients with locally recurrent breast cancer, that using a pedicled latissimus dorsi musculocutaneous ap or a pedicled rectus abdominis musculocutaneous ap, and a piece of titanium mesh if necessary, is reasonable and practical. We will furtherly make a larger sample size analysis for more robust evidence.

Declarations
Ethics approval and consent to participate The study was approved by ethical review board of China Medical University, which followed the ethical principles of the Declaration of Helsinki 1964, and all the participantsprovided the written informed consent.

Consent to publish
Written consent for publication was obtained from the patient for information and medical images about the patient himself/herself. All the patients also understand that the text and any pictures will be freely available on the internet and may be seen by the general public.

Availability of data and materials
The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Competing interests
The authors declare that they have no competing interests.

Figure 1
A 57-year-old female patient with locally recurrent breast cancer. Patient with locally recurrent breast cancer and preoperative design of skin ap (A). The heart and lung were all exposed (B). A piece of titanium mesh used to stabilize the thoracic cage defect (C). The pedicled rectus abdominis musculocutaneous ap formation to coverage the chest wall defect (D). A pedicled aponeurosis ap of obliquus externus abdominis about 10 cm×5 cm and a piece of e-PTFE about 8 cm×6 cm used to stabilize the abdominal wall and eliminate the abdominal tension (E). Outcome of the patient after operation (F). The patient recovered very well without any complication. The titanium micromesh affects X-ray image (G) but not CT scan (H). tm, titanium micromesh.