Oncoplastic Reconstructive Breast Surgeon (ORBS) Performance and Impact on Breast Reconstructions: Clinical Outcome, Learning Curve, and Patient Reported Aesthetic Results- An analysis of 451 Procedures

Oncoplastic and reconstructive breast surgeon (ORBS) aimed to incorporate aesthetics and plastic technique into breast cancer operations to balance the oncologic safety and cosmetic outcome, and also to promote breast reconstructions. The outcome of breast reconstruction performed by an ORBS was reported from a single institute. Among the 451 breast reconstructions performed by an ORBS, 75.8% were gel implant reconstructions, 3.3% were tissue expander, 16.9% were transverse rectus abdominal myocutaneous (TRAM) ap, 3.1% latissimus dorsi (LD) ap, and 0.9% LD ap + implant. The patients reported aesthetic evaluation showed that 53.9% responded excellent, 41.1% good, 4.4% fair, and 0.6% poor. In cumulative sum plot learning curve analysis, it took around 58 procedures for an ORBS to be familial with mastectomy followed by immediate gel implant reconstruction and to signicantly decrease the operation time. In multivariate analysis, younger age, MRI, nipple sparing mastectomy, ORBS, and high-volume surgeon were factors related to breast reconstructions. Current study demonstrated that a breast surgeon after adequate training could become an ORBS and perform breast reconstructions with adequacy. Complimentary to traditional breast surgeon-to-plastic surgeon breast reconstruction pathways, ORBS could increase breast reconstructions rate, which remained low worldwide.


Introduction
Breast reconstructive procedures and related surgical trainings have traditionally been performed by plastic surgeons, however, a paradigm shift has recently taken place [1][2][3][4]. A formal inter-specialty training program has been established in UK since 2002 [2,5]. Oncoplastic and reconstructive breast surgeon (ORBS) aimed to incorporate aesthetics and plastic technique into breast cancer operations to not only achieve the oncologic safety and cosmetic outcome simultaneously, and also to promote breast reconstructions [3,[6][7][8]. The ORBS training program was started in England and Europe, and now became widespread around the world [1][2][3][4][5][6][8][9][10][11]. The program incorporated lectures and training courses to assist breast surgeons to acquire breast reconstruction techniques and plastic surgeons to be familiar with breast cancer operations (dual trained system) [1,3,[8][9][10]12].
In clinical practice, it is important to evaluate the quality of patient care and treatment [11,13,14], and the results and quality of the breast reconstructions performed by ORBS should be reported and monitored [12,15]. Would breast reconstructions performed by ORBS achieve the same level of safety and satisfaction comparable to plastic surgeon (PS)? Would BS receiving ORBS training increase breast reconstruction rate? A few studies focusing on the results of breast reconstructions performed by ORBS have been reported [12,15] . However, the type, quality, and impact of ORBS on breast reconstructions were rarely stated, and many questions remain unanswered.
It's time to evaluate the impact of ORBS on rate and quality of breast reconstructions, and studies are needed to objectively evaluate this dual-trained program [12]. The aim of current study is to evaluate the preliminary results of breast reconstructions program conducted by an ORBS in a single institute, and to evaluate patient reported outcomes (PRO) following breast reconstructions performed by ORBS. The impact of the ORBS on the rate of breast reconstructions, the type and quality of breast reconstructions performed by the ORBS would be analyzed and reported.

Results
A total of 451 breast reconstructions procedures were performed by one ORBS (HWL) during study period, and 448 were immediate breast reconstructions (IBR) while 3 were delayed. Among the 448 mastectomies, 337 (75.2%) were nipple sparing related, and 34.4% (129/374) were associated with lymph node metastases. Among the 451 breast reconstructions performed by the ORBS, 342 (75.8%) were gel implant reconstructions, 15 (3.3%) were tissue expanders, 76 (16.9%) were TRAM aps, 14 (3.1%) were LD aps, and 4(0.9%) LD ap + implants. The clinical manifestations of these patients were summarized in Table 1. The pre-and post-reconstruction images were demonstrated in Figure 1.  (Table 3). Moreover, ORBS had shown competency with PS in providing diverse types of breast reconstructions other than microsurgery related procedures.  Figure 2 b-f. The time needed for ORBS to complete mastectomy and IGBR decreased gradually (Figure 2b). The implant loss rates were 4% (2/50) in the rst 50 implant-related breast reconstructions, 2% (1/50) in 51 th to 100 th cases, and 1% (1/100, Figure 2c) thereafter. The overall satisfaction rate of breast reconstructions increased in paralleled with accumulation of experiences (Figure 2d, e). In CUSUM plot learning curve analysis, it took around 58 procedures for an ORBS to be familiar with mastectomy and IGBR and signi cantly decreased operation time (Table 2, Figure 2f).During the study period, the distributions of breast reconstructions cases and their corresponding primary breast surgeons were shown in Figure 3a.
The breast reconstruction referral rates varied widely from different breast surgeons. Factors related to breast reconstructions were evaluated (

Discussion
In current study, we reported the preliminary outcome of 451 breast reconstructions performed by one ORBS, who initially was a BS and received international oncoplastic and reconstructive breast surgery training program. The preliminary results showed that the clinical outcome was acceptable, and there was no total ap failure in autologous breast reconstructions. The implant failure rate was 1.4%, which was low compared to around 8% implant failure rate reported in a meta-analysis of breast cancer patients with IBR [16]. We observed a high patient-reported satisfaction rate (Figure 2a), with 95% of the study population reporting being satis ed (good: 41.1%; excellent: 53.9%) which is comparable with an earlier study published by Roberson et al [15]. Moreover, an earlier report by He et al [13] also demonstrated that having breast surgeon specialists performed IBRs doesn't seem to negatively affect outcome.
Additionally, we found that ORBS also had positive impacts on rate of breast reconstructions (Figure 3a, Table 4).
IBR with implant have been employed as a mainstream option of breast reconstructions after early breast cancer treatment [13,[17][18][19], and implant failure is an important quality-indicator for the performance of reconstructive surgeon [16]. According to literature review meta-analyses results, around 8% of breast cancer patients with IBR suffered from implants loss [16]. Another study, in which breast reconstructions were performed by breast surgeons, showed a 4.9% (11/223) of implant extrusion rate due to infection [15]. The 1.4% (5/361) implant failure rate from the ORBS in the current study is low and acceptable. Factors predisposing to implant loss had been reported, radiotherapy, uncontrolled infection, obesity, and ptosis breasts were important risk factors [15,16]. Whenever patients with the above mentioned risk factors are indicated for IBR, autologous breast reconstruction would be a safe alternative [17][18][19].
A quali ed ORBS should be able to provide immediate or delayed breast reconstructions, which include implant types and/or autologous breast reconstructions [3,9,15]. Other than 361 implant insertions, our breast reconstructions program by ORBS also performed 94 autologous ap breast reconstructions (76 TRAM ap, 18 LD ap, Figure 1, Table 1, 3), laparoscopically harvested omentum ap, and other local aps for partial breast reconstructions or repair of soft tissue defects. Compared with BS, who did not receive oncoplastic reconstructive breast training and provided only implant type breast reconstructions, a trained ORBS was able to provide more diversity of breast reconstruction services and in the same time, demonstrated a similar level of competency to PS (SLL) at the same year-of-service for breast reconstructions without microsurgeries (Table 3). Usually ORBS do not receive formal micro-surgery related trainings, therefore whenever the breast reconstructions involving the use of microsurgery techniques, consultation with PS, who experienced with microsurgeries, is recommended.
The impact of cases accumulation to the performance of an ORBS was rarely reported. We found that the operation time decreased, and implant failure rate dropped from 4% to 1% during study period after more cases experience accumulated (Figure 2b, c). From CUSUM plot, about 58 procedures were required for an ORBS to be familiar with the procedures of mastectomy and IGBR (Table 2, and Figure 2f), and the operation time together with blood loss were signi cantly decreased after initial learning phase. The patients' reported satisfaction rate also increased steadily when more breast reconstructions performed by ORBS (Figure 2). These results supported that a BS after formally ORBS training could perform breast reconstructions and provided high quality services after adequate cases experience accumulated.
Breast reconstruction is traditionally going from breast cancer operation performed by BS (or general surgeon) then breast reconstruction part performed by PS [1,12] (Figure 3b). This system had the advantage of different surgeons perform the best part of their work, however, some disadvantages remained unsolved [1]. For example, if the breast surgeons do not refer patients for breast reconstructions (as shown in Figure 3a), then patients may not have the chance to have breast-reconstruction consultations or operations provided by PS [20][21][22]. Sometimes, the BS or at the hospital just do not have adequate PS to perform the breast reconstructions [21][22][23][24][25]. These were some of the reasons that breast reconstructions rate remained low (around 10-25%) around the world today [9,21,23,26].
At our institute, and I believed some other hospitals in the world [1,7,9,12,13,15], now adopted the two tracts system, which allowed both the traditional two-team system (BS performed breast cancer operations then PS do the breast reconstructions) or the ORBS system (ORBS or dual-trained surgeons [12] do the mastectomies and reconstructions, Figure 3b). Patients could be referred from BS to PS for breast reconstructions or BS could work with ORBS doing breast reconstructions. ORBS (or dualtrained surgeon [12]) are capable of carrying out breast cancer operations and breast reconstructions.
Herrick et al. [12] had shown that patients received dual-train surgeons' services (mastectomy and reconstruction) required fewer doctor visit, and have signi cant socioeconomic and psychological bene ts. In some cases, when breast reconstructions involving micro-surgeries, ORBS could work with PS for breast reconstructions.
The concept of ORBS, which originated in early 2000 in UK and Europe, was aimed to incorporate aesthetics and plastic technique into breast cancer operations, and to promote breast reconstructions [1-3, 5, 6]. In our multivariate analysis for factors predisposing breast reconstruction (Table 4), younger age (OR=0.92), breast MRI (OR=3.74), NSM (OR:7.40), ORBS (OR:1.84), and high-volume surgeon (OR:6.96) were important factors. Our ndings supported that ORBS could increase breast reconstruction rate, and con rmed that the primary breast surgeons played import roles [20-22, 27, 28]. High volume surgeon (de ned as cases larger than 100 per year) and ORBS were important contributing factors affected patients receiving breast reconstructions (Table 4, Figure 3a).
This study is limited due to its single institutional study without multi-centers' data to con rm the hypothesis that breast surgeons after adequate training could be transformed to ORBS and perform breast reconstructions with adequacy. As each BS received different surgical training and had quite different practice behaviors. The experience and results derived from current study might not be applied to other surgeons, hospitals or regions in the world. More studies and reports from other ORBS were needed to consolidate this concept. The questionnaire, which had been used and published in our previous studies [29][30][31][32], we used at current report was different from the common used questionnaire like "BREAST-Q" [14], and might not be so comprehensive and well adopted. Based on our experiences, a surgeon to be trained as an ORBS should be a certi ed breast surgeon, who is familiar with conventional breast cancer operations and treatment. Furthermore, he/she should receive reconstructive breast surgeries training in a high volume (≥100 cases per year) reconstructive breast surgeries centers with adequate training duration (≥ 6 months).
In conclusion, we demonstrated that a breast surgeon after adequate training could become an ORBS and perform breast reconstructions with adequacy. Following more cases' experience accumulations, the performance of ORBS increased gradually in term of decreasing operation time, less implants loss, and increased patients' reported satisfactions. In complimentary to traditional BS to PS pathways, ORBS could increase breast reconstructions, which were remained under-performed in the world.

Patients
Patients who received breast reconstructions from 1 January 2011 to 31 May 2020 were retrieved from a prospectively collected oncoplastic reconstructive breast surgery database at Changhua Christian Hospital, a tertiary medical center at central Taiwan. We started a breast reconstruction program by ORBS at our institution since 2011 after one of our breast surgeons (HWL), who is a certi ed breast surgeon and dedicated to breast cancer operations, received an international ORBS training program overseas at

Clinical outcome and Patients-reported aesthetics results
The safety of breast reconstructions was monitored with operative time, hospital stay, and events of major complications. Brest reconstructions failure, de ned as implant loss or total ap loss in autologous breast reconstructions was regularly followed. The implant loss rate, which de ned as explant due to surgery related complication occurred within 3 months post operation, was recorded.
Patients-reported aesthetic results following breast reconstruction were assessed using a selfadministered questionnaire, which had been used in our previous studies [29][30][31][32]. The self-administered questionnaire, which was designed to evaluate the aesthetic result of breast cancer patients received breast reconstruction, was conducted at 3 months after the operation when their surgical wounds had healed.
The questionnaire comprised of 10 questions (supplementary le) and 4 itemized scales, which were graded as "1, poor", "2, fair", "3, good", and "4, excellent". To evaluate the overall satisfaction score of breast reconstructions, the total score of question #2 to 9 in each patient was tabulated. Those with an overall score of 8-11 was graded as poor, a score of 12-19 graded as fair, a score of 20-27 graded as good, and a score of 28-32 graded as excellent. Patients with results graded as 'excellent' or 'good' were de ned as being satis ed with the cosmetic outcome.

Impact of cases experience accumulation, and competence of breast reconstructions performed by ORBS
To evaluate the impact of cases experience accumulation of ORBS and outcome of breast reconstruction, the total operation time needed for mastectomy and immediate gel implant reconstruction (IGBR), the events of implant loss, and patient-reported aesthetic results were arranged in chronologic sequence. The competency of ORBS in performance of breast reconstruction was further evaluated by comparing breast reconstructions types performed with different surgeons at the same hospital. One breast surgeon (BS), who performed breast reconstructions without formal oncoplastic breast reconstruction training, and another PS (SLL) the same years-of-service were selected for comparisons.

Learning curve evaluation of mastectomy and IGBR
Cumulative sum (CUSUM) plot analysis is a frequently adopted analytic method[33] for learning curve evaluation. To evaluate the impact of case experience accumulation for an ORBS on the operation time of mastectomy and IGBR, the "overall operation time" was gathered and plotted in a chronological order.
The CUSUM plot[34] was used to analyze the learning curve, and a learning curve is considered complete when a point for decreasing surgical time was observed from the CUSUM plot. The "overall operation time" was de ned as the time taken from the skin incision, mastectomy, gel implant reconstruction to the end of wound closure. The "overall operation time" also included the time taken for procedures such as axillary surgery, mastectomy, reconstruction with gel implants, drains placement, and wound closure.

Factors of breast reconstructions and impact of ORBS
Clinical and pathological factors related to breast reconstruction were also surveyed. Two groups of patients, which consisted of 850 breast reconstruction patients and another 1001 no breast reconstruction patients, were compared to identify clinical or pathologic factors related to breast reconstructions. Factors surveyed included age, body mass index (BMI), tumor size, breast MRI, histologic grade, stage, intrinsic subtypes, lymph node metastasis, NSM, nipple invasion, ER, PR, HER-2, Ki-67, surgeon type (ORBS versus other), and volume of surgeon (high volume versus low volume). High volume of surgeon was de ned as breast cancer >100 cases per year.
To evaluate the impact of primary caring breast surgeon on patients' subsequent breast reconstructions, the case number and distribution of breast reconstructions were traced to their primary caring breast surgeons and listed in sequential year.

Statistical Analysis
Data are expressed as mean ± standard deviation (SD) for continuous variables. We used the chi-square test for categorical comparisons of data, and differences in means of continuous variables were tested by the Student's t test. A p value of less than 0.05 was considered to indicate statistical signi cance and all tests were two-tailed. All statistical analyses were performed with the statistical package SPSS for  signi cantly. c. Implant loss events and cases accumulation. The implant loss rates were 4% (2/50) in the rst 50 implant-related breast reconstructions, 2% (1/50) in 51th to 100th cases, and 1% (1/100) thereafter. d. Patients satisfaction of all type breast reconstructions and cases accumulations. The overall satisfaction rate of breast reconstructions increased paralleled with more cases experience accumulated. e. Patients satisfaction of implant type breast reconstructions and cases accumulations.
The overall satisfaction rate of implant type breast reconstructions increased paralleled with more cases experience accumulated. f. Cumulative sum plot of learning curve for ORBS performing mastectomy and immediate gel implant breast reconstruction (IGBR). It showed that it took 58 procedures for the ORBS to familial mastectomy and IGBR, and showed signi cantly decreased operation time.

Supplementary Files
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Supplementary le.pdf