Oncoplastic breast surgeries with a conservative approach have become a preferred option compared to radical procedures such as mastectomy due to their equivalent survival rate, breast preservation [1] , improved aesthetic outcomes, and measurable psychological benefits [2] . About 60% of patients diagnosed with breast cancer in the United Kingdom undergo breast-conserving surgery (BCS), and a subset of them require either volume replacement or displacement technique to improve overall aesthetic outcomes [3] [4] [5] [6] . The decision to use either method is determined by the surgeons’ experience and the size of the tumor in comparison to the remaining breast tissue [5] [7] . A volume replacement technique is indicated in small to medium-sized breasts with minimal ptosis, especially in larger tumors that lead to a more significant cavity defect. For decades, the latissimus dorsi (LD) flap has been a key donor site for total and partial breast reconstruction. Still, it is linked with donor site morbidity and impaired functional outcome [8] [9] [10] .

Over two decades ago, Hamdi et al. [11] [12] [13] described perforator flaps as skin and fat flaps based on perforators arising from a deep vascular system through the underlying muscles or intermuscular septum. The introduction of perforator flaps in BCS has allowed surgeons to keep muscle function intact and reduce surgical morbidity while potentially filing the volume defect with an excellent aesthetic outcome [14] [15] .

The chest wall perforator flaps (CWPF) are based on cutaneous perforator branches of posterior and anterior intercostal arteries, forming an arcade between the aorta and internal mammary artery. The arcade is divided into vertebral, costal, and muscular segments leading to the dorsal and lateral anterior perforators. A lateral thoracic artery perforator flap can be used exclusively or with a lateral intercostal artery perforator (LICAP) flap to reconstruct laterally situated excision defects. The potential advantages of these techniques could be sparing the LD muscle and avoiding a mastectomy in a large tumor [16] .

Volume replacement technique using CWPF has become popular in the last two decades. Over 60 articles [5] [6] [7] [17] - [27] relating to partial breast reconstruction have been published, including systematic reviews on oncoplastic breast conservation surgery [28] . There has been a few landmark publications describing the techniques, feasibility and indications of chest wall perforator flap based partial breast reconstructions which has significantly helped to bring this modalities in the in the reconstructive breast surgery field [11] [29] . However, there is a lack of high-quality randomized control trials (RCT) or prospective studies with long-term follow-ups to demonstrate the safety and acceptability of CWPF for partial breast reconstruction following BCS for breast cancer. Although in the past fewer centers routinely performed these procedures [30] - [35] , the most recent systematic review by Pujji et al. has shown that the use of CWPF is a safe method for partial breast reconstruction with a low complication rate, acceptable short-term oncological outcomes, and satisfactory cosmetic outcome [28] .

This article aims to conduct a feasibility study with outcome analysis of a prospectively maintained database of partial breast reconstruction using CWPF at Sherwood Forest Hospitals NHS Foundation Trust equipped with a full range of oncoplastic services.

A database was set up to include all patients from 1^st January 2018 to 30^th June 2022 undergoing BCS and partial breast reconstruction with intercostal artery perforator (ICAP), or lateral thoracic artery perforator (LTAP) flaps at Sherwood Forest Hospitals NHS Foundation Trust. Patient information, including patients’ age, body mass index (BMI), smoking status, bra size, type of CWPF procedure, and previous treatments were reordered for each patient.

Multidisciplinary team (MDT) meetings discussed patients considered suitable for the procedure. Only patients with primary cancer, small to moderate-sized breasts (with a few exceptions), grade I to II ptosis, non-diabetics, BMI below 35, no cardiovascular diseases, and no previous use of radiotherapy were considered. Further patient selection criteria included relative tumor-to-breast ratio for upper outer quadrants and any excision required in the lower inner and outer quadrants. Depending on the breast volume, presence of ptosis, and tumor size/location, the surgeon would also evaluate the patients to determine the appropriate technique for reconstruction. The area beneath the inframammary fold was divided into three sections; the medial segment is referred to as medial ICAP (MICAP), the middle third is referred to as anterior ICAP (AICAP) the lateral segment is referred to as lateral ICAP (LICAP). The LTAP (Figure 1) and LICAP (Figure 2) flaps were used for defects in the lateral quadrants of the breast, The MICAP (Figure 3) flap was used for lower inner quadrant defects, while the AICAP (Figure 4) flap was used for lower central breast defects. Therefore the perforator flap selection was primarily based on the tumor location. Patients were then examined in both sitting and lying down positions to indicate tumor location, post-BCS defect, and flap markings were made. The width of the flap is based on the estimated breast defect and the available donor skin facilitating adequate closure. The length of the flap can be variable, and up to 30 cm of the flap can be harvested without vascular compromise, and this would again depend on the amount of tissue needed for the defect. On the surgery day,

the surgeon drew the incision markings on the patient to explain where the scars would be after the operation. Hand-held Doppler was used for mapping out the underlying blood vessels for blood supply to the flap. All surgeries are done with wide local excision and reconstruction in a one-stage with or without axillary surgery, as indicated. Patients were positioned supine with arms extended in case of axillary surgery. To provide the best access to LTAP/LICAP donor site, a saline bag was placed beneath the ipsilateral para-spinal area. All patients were given one dose of antibiotics before surgery. The flaps were de-epithelized before putting them in the resection cavity. No drains were used. After the procedure, the patients were discharged on the same day or the next day, depending on each patient’s circumstances. Patients were followed up one week after the procedure by the breast care nurse for a wound check and at three weeks by clinicians for consultation and review of post-op histology results to discuss plans regarding any further treatment needed as per national guidelines. Outcomes, including tumor size, measured clinically, via imaging and histologically, margins involvement, biopsy results, specimen weight, re-excision surgery, and complications, were recorded into the database.

The data was assembled in an excel sheet using Microsoft EXCEL 2016. Filters were applied to each column to calculate the total number of patients in each category. The average or percentage was derived from the total number of patients in the study for each recorded variable.

Eighty-one patients were selected based on the following criteria: all presented with primary cancers, small to moderate-sized breasts (with a few exceptions), grade I to II ptosis, non-diabetics, BMI below 35, no cardiovascular diseases, and no previous use of radiotherapy. The demographic characteristics, treatment details, and tumor characteristics are given in Table 1. The average age of the patients was 55.7 years, with the average body mass index (BMI) at 26.7 kg/m². The bra size varied between A to FF with A (7.4%), B (28.3%), C (38.2%), D (13.6%),

Values are average with (range) or percentage (%). BMI, body mass index; CWPF, chest wall perforator flap; LTAP, lateral thoracic artery perforator; LICAP, lateral intercostal artery perforator; AICAP, anterior intercostal artery perforator; MICAP, medial intercostal artery perforator; NACT, Neoadjuvant chemotherapy; USS, ultrasound; MRI, magnetic resonance imaging; DCIS, ductal carcinoma in situ; SSI, surgical site infection.

DD (11.1%) and FF (1.2%). Seven patients were smokers at the time of their surgery. 14.8% of the patients had neoadjuvant chemotherapy (NACT). LICAP and/or LTAP flaps were used in 64.2% of patients, AICAP was used in 19.8%, and MICAP was used in 16%. The average specimen weight was 26.7 g. Most patients were discharged the same day or the next day after surgery. The average tumor size measured clinically was 15.75 mm, via imaging was 19.1 mm, and histologically measured tumor size was 19.6 mm. 16% of the patients had involved margins on histology, and 12.3% underwent re-excision surgery. Biopsy results showed that 16% of the tumors were DCIS and 84% were invasive. 2 patients underwent a completion mastectomy.

Five patients had surgical site infections (SSI). Three patients had flap complications, including sinus and infection, leading to loss. Four patients had flap shrinkage. Three patients had a hematoma. Fourteen patients had other complications, including seroma requiring aspiration and fat necrosis. No delayed complications were reported. None of the patients required a symmetrization procedure on the contralateral side.

Various oncoplastic procedures have been reported for resecting large tumors with an acceptable safety margin and satisfactory outcomes [20] [25] [26] [36] [37] [38] [39] [40] . The procedure selection process depends on factors such as breast size/ptosis, tumor location, and morbidity. Although volume replacement techniques can maintain the volume and shape of the breast and avoid contralateral surgery to reach symmetry [6] [26] , this technique is related to higher donor site morbidity due to its complexity [11] [12] [29] [41] . Lateral thoracic skin and subcutaneous tissue, introduced in 1986 [23] , have been used as fasciocutaneous flaps for breast reconstruction. As described by Clough et al. [20] and Kroll et al. [37] , these techniques lead to excessive and unpleasant scarring and overall unsatisfactory results. In the 1970s, the musculocutaneous flap was introduced [42] [43] [44] [45] but later the ICAP flap was reintroduced as a perforator flap for reconstructing defects over the thorax [11] . According to Hamdi et al., these flaps could be based on intercostal perforators arising from coastal or muscular segments of the intercostal vessels and lead to reliable use for the BCS reconstruction [11] . Roy and Tenovici [34] initially reported a two-stage surgical approach for patients with a high tumor to breast ratio. In this case, after a wide local excision is made the resection cavity was filled with saline, and the LICAP/LTAP flap reconstruction was performed after the histology results were reviewed to dictate the second surgery. Over time with experience and surgical advancement, this technique is now performed as a one-stage surgery for those with an ideal tumor to breast ratio. The skin of the ICAP flap from the lateral and anterior thoracic region has the same texture as breast skin leading to a favorable result. Secondly, the LICAP flap is based on the anterior perforator to the LD muscle, so it does not compromise the thoracodorsal vessels [46] . Compared to the latissimus flap, the present technique has further advantages as it is less time-consuming, does not require any unique positioning for the procedure, and there is no loss of muscle function. In fact, with the CWPF method, the latissimus flap is spared as an option for future use in case of local recurrence. The scars are also well concealed postoperatively on frontal view images.

In our study, we aimed to prove the effectiveness of CWPF for BCS and partial breast reconstruction. All 81 patients presented with primary cancers, small to moderate-sized breasts (with a few exceptions), grade I to II ptosis, non-diabetics, BMI below 35, no cardiovascular diseases, and no previous use of radiotherapy. Hand-held Acoustic Doppler was used to assess vessel location preoperatively and intra-operatively to avoid dissecting vessels and ultimately minimize chances of injury. LICAP/LTAP flaps are good options for one-stage partial breast reconstruction in small to moderate-sized breasts with minimal ptosis. During LICAP, the flap is turned at its junction with the vessels, subsequently limiting mobility and making it suitable for lateral breast defects. On the contrary, the LTAP flaps have increased mobility due to the vessels being placed superiorly, letting the flap rotate freely and filling the cavity better [33] . In our sample, 64.2% of patients had LICAP or LTAP and 19.8% AICAP, and 16% underwent MICAP. All surgeries were done as a one-stage procedure. These procedures are suitable for most patients as the main potential contraindications for ICAP is lack of adequate donor tissue or previous surgery in the donor area, which can be linked to prior perforator damage. These procedures can be performed either by a breast surgeon trained in oncoplastic techniques or a combined team of breast and plastic surgeons.

According to our study, most complications were minor; 12.3% of patients required re-excision, and only two needed completion mastectomy. Similar to a recent study by Soumian S. et al. [47] where 13.39% of the patients required margin re-excision, and only one patient ultimately received a mastectomy due to persistent positive margins after re-excision. None of the complications increased the hospital stay or interfered with the adjuvant treatment. Flap complications, including flap shrinkage, were experienced by seven patients. Extra care must be taken with high-risk patients such as smokers and patients with associated comorbidities.

The main limitation of our study is that as it is a case series, it needs long-term follow-up. A longer follow-up is required for significant conclusions regarding patient satisfaction. Therefore, we are currently working on a study with patient-reported outcomes and long-term follow-up data. We hope this future study will provide further insight into the effectiveness of this procedure and provide robust data, including patient satisfaction and the effect of radiotherapy on the flaps.

Our observational study demonstrated that partial breast reconstruction performed with chest wall perforator flaps is an acceptable option for volume replacement technique in breast-conserving surgery in well-selected patients. It yields satisfactory results for the patients and acceptable post-operative complications. Future studies specifically considering long-term follow-up are recommended to establish this technique’s effectiveness further.

We sincerely thank Dr. Muzina Akhtar, Mr. Ghassan Elamin, Dr. Brindusa Muntean, Mr. Ali Jahan and Dr. Wajiha Tehniyat for their help with the study.

The authors declare no conflicts of interest regarding the publication of this paper.

Dube, M.K., Sharma, R.D. and Puthu, D. (2023) Surgical Outcomes Following Partial Breast Reconstruction with Chest Wall Perforator Flaps. Surgical Science, 14, 277-288. https://doi.org/10.4236/ss.2023.144031