The impact of the new ESTRO-ACROP target volume delineation guidelines for postmastectomy radiotherapy after implant-based breast reconstruction on breast complications.

The European Society for Radiotherapy and Oncology-Advisory Committee in Radiation Oncology Practice (ESTRO-ACROP) updated a new target volume delineation guideline for postmastectomy radiotherapy (PMRT) after implant-based reconstruction. This study aimed to evaluate the impact on breast complications with the new guideline compared to the conventional guidelines. In total, 308 patients who underwent PMRT after tissue expander or permanent implant insertion from 2016 to 2021 were included; 184 received PMRT by the new ESTRO-ACROP target delineation (ESTRO-T), and 124 by conventional target delineation (CONV-T). The endpoints were major breast complications (infection, necrosis, dehiscence, capsular contracture, animation deformity, and rupture) requiring re-operation or re-hospitalization and any grade ≥2 breast complications. With a median follow-up of 36.4 months, the cumulative incidence rates of major breast complications at 1, 2, and 3 years were 6.6%, 10.3%, and 12.6% in the ESTRO-T group, and 9.7%, 15.4%, and 16.3% in the CONV-T group; it did not show a significant difference between the groups (p = 0.56). In multivariable analyses, target delineation is not associated with the major complications (sHR = 0.87; p = 0.77). There was no significant difference in any breast complications (3-year incidence, 18.9% vs. 23.3%, respectively; p = 0.56). Symptomatic RT-induced pneumonitis was developed in six (3.2%) and three (2.4%) patients, respectively. One local recurrence occurred in the ESTRO-T group, which was within the ESTRO-target volume. The new ESTRO-ACROP target volume guideline did not demonstrate significant differences in major or any breast complications, although it showed a tendency of reduced complication risks. As the dosimetric benefits of normal organs and comparable oncologic outcomes have been reported, further analyses with long-term follow-up are necessary to evaluate whether it could be connected to better clinical outcomes.

Dynamic insights into infection risk over time in two-stage implant-based breast reconstruction: a retrospective cohort study.

BACKGROUND: Infections following postmastectomy implant-based breast reconstruction (IBR) can compromise surgical outcomes and lead to significant morbidity. This study aimed to discern the timing of infections in two-stage IBR and associated risk factors. METHOD: A review of electronic health records was conducted on 1096 breasts in 1058 patients undergoing two-stage IBR at Seoul National University Hospital (2015-2020). Infections following the first-stage tissue expander (TE) insertion and second-stage TE exchange were analyzed separately, considering associated risk factors. RESULTS: Over a median follow-up of 53.5 months, infections occurred in 2.9% (32/1096) after the first stage and 4.1% (44/1070) after the second stage. Infections following the first-stage procedure exhibited a bimodal distribution across time, while those after the second-stage procedure showed a unimodal pattern. When analyzing risk factors for infection after the first-stage procedure, axillary lymph node dissection (ALND) was associated with early (≤7 weeks) infection, while both ALND and obesity were independent predictors of late (>7 weeks) infection. For infections following the second-stage procedure, obesity, postmastectomy radiotherapy, a history of expander infection, ALND, and the use of textured implants were identified as independent risk factors. Postmastectomy radiotherapy was related to non-salvaged outcomes after infection following both stages. CONCLUSION: Infections following first and second-stage IBR exhibit distinct timelines reflecting different pathophysiology. Understanding these timelines and associated risk factors will inform patient selection for IBR and aid in tailored postoperative surveillance planning. These findings contribute to refining patient suitability for IBR and optimizing personalized postoperative care strategies.

Improvement of Shoulder Motion in Two-Stage Dual-Plane Implant-Based Breast Reconstruction followed by Radiation Therapy through Delayed Prepectoral Conversion.

Background Although prepectoral implant-based breast reconstruction has recently gained popularity, dual-plane reconstruction is still a better option for patients with poor-quality mastectomy skin flaps. However, shoulder morbidity is aggravated by subpectoral reconstruction, especially in irradiated patients. This study aimed to demonstrate shoulder exercise improvement in subpectoral reconstruction by delayed prepectoral conversion with an acellular dermal matrix (ADM) inlay graft technique at the time of expander-to-implant exchange after irradiation. Methods Patients with breast cancer treated for expander-to-implant exchange after subpectoral expander insertion and subsequent radiotherapy between January 2021 and June 2022 were enrolled. An ADM inlay graft was inserted between the pectoralis major muscle and the previously inserted ADM. The ADM was sutured partially overlapping the pectoralis muscle from the medial side with the transition part, to the muscle border at the lateral side. Perioperative shoulder joint active range-of-motion (ROM) for forward flexion, abduction, and external rotation was also evaluated. Results A total of 35 patients were enrolled in the study. Active shoulder ROM significantly improved from 163 degrees preoperatively to 176 degrees postoperatively in forward flexion, 153 to 175 degrees in abduction, and 69 to 84 degrees in external rotation. There was no difference in patient satisfaction regarding the final outcome between the conventional prepectoral reconstruction group and the study group. Conclusion Shoulder exercises in irradiated patients who underwent subpectoral reconstruction were improved by delayed prepectoral conversion using an ADM inlay graft. It is recommended that subpectoral reconstruction not be ruled out due to concerns regarding muscle contracture and shoulder morbidity in radiation-planned patients with poor mastectomy skin flaps.

Hybrid Lymphovenous Anastomosis Surgery Guided by Intraoperative Mesenteric Intranodal Lymphangiography for Refractory Nontraumatic Chylous Ascites: A Case Report.

Refractory chylous ascites can cause significant nutritional and immunologic morbidity, but no clear treatment has been established. This article introduces a case of a 22-year-old female patient with an underlying lymphatic anomaly who presented with refractory chylous ascites after laparoscopic adnexectomy for ovarian teratoma which aggravated after thoracic duct embolization. Ascites (>3,000 mL/d) had to be drained via a percutaneous catheter to relieve abdominal distention and consequent dyspnea, leading to significant cachexia and weight loss. Two sessions of hybrid lymphovenous anastomosis (LVA) surgery with intraoperative mesenteric lymphangiography guidance were performed to decompress the lymphatics. The first LVA was done between inferior mesenteric vein and left para-aortic enlarged lymphatics in a side-to-side manner. The daily drainage of chylous ascites significantly decreased to 130 mL/day immediately following surgery but increased 6 days later. An additional LVA was performed between right ovarian vein and enlarged lymphatics in aortocaval area in side-to-side and end-to-side manner. The chylous ascites resolved subsequently without any complications, and the patient was discharged after 2 weeks. The patient regained weight without ascites recurrence after 22 months of follow-up. This case shares a successful experience of treating refractory chylous ascites with lymphatic anomaly through LVA, reversing the patient's life-threatening weight loss. LVA was applied with a multidisciplinary approach using intraoperative mesenteric lipiodol, and results showed the possibility of expanding its use to challenging problems in the intraperitoneal cavity.

Norepinephrine preserved flap blood flow compared to phenylephrine in free transverse rectus abdominis myocutaneous flap breast reconstruction surgery: A randomized pilot study.

BACKGROUND: Vasopressors are used in up to 85% of cases during free flap surgery. However, their use is still debated with concerns of vasoconstriction-related complications, with rates up to 53% in minor cases. We investigated the effects of vasopressors on flap blood flow during free flap breast reconstruction surgery. We hypothesized that norepinephrine may preserve flap perfusion better than phenylephrine during free flap transfer. METHODS: A randomized pilot study was performed in patients undergoing free transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction. Patients with peripheral artery disease, allergies to study drugs, previous abdominal operations, left ventricular dysfunction, or uncontrolled arrhythmias were excluded. Twenty patients were randomized to receive either norepinephrine (0.03-0.10 µg/kg/min) or phenylephrine (0.42-1.25 µg/kg/min) (each n = 10) to maintain a mean arterial pressure of 65-80 mmHg. The primary outcome was differences in mean blood flow (MBF) and pulsatility index (PI) of flap vessels after anastomosis measured using transit time flowmetry in the two groups. Secondary outcomes included flap loss, necrosis, thrombosis, wound infection, and reoperation within 7 days postoperatively. RESULTS: After anastomosis, MBF showed no significant change in the norepinephrine group (mean difference, -9.4 ± 14.2 mL/min; p = 0.082), whereas it was reduced in the phenylephrine group (-7.9 ± 8.2 mL/min; p = 0.021). PI did not change in either group (0.4 ± 1.0 and 1.3 ± 3.1 in the norepinephrine and phenylephrine groups; p = 0.285 and 0.252, respectively). There were no differences in secondary outcomes between the groups. CONCLUSION: During free TRAM flap breast reconstruction, norepinephrine seems to preserve flap perfusion compared to phenylephrine. However, further validation studies are required.

Redo hepatic artery reconstruction for thrombosis without retransplantation in 1355 adult living donor liver transplantations.

Hepatic artery thrombosis (HAT) after liver transplantation is associated with a marked increase in morbidity, leading to graft and patient loss. We evaluated the outcomes of adult living donor liver transplantation patients with HAT under an aggressive surgical intervention. A total of 1355 recipients underwent adult living donor liver transplantation at the Seoul National University Hospital. Surgical redo reconstruction for HAT was performed in all cases except in those with graft hepatic artery injury and late detection of HAT. Postoperative HAT developed in 33 cases (2.4%) at a median time of 3.5 days. Thirty patients (90.9%) underwent redo-arterial reconstruction. The survival rates in patients with HAT were similar to the rates in those without HAT (72.7% vs. 83.8%, p = 0.115). Although graft survival rates were lower in patients with HAT (84.8%) than in those without HAT (98.0%) ( p < 0.001), the graft survival rate was comparable (92.0% vs. 98.0%, p = 0.124) in the 25 patients with successful revascularization. Biliary complication rates were higher in patients with HAT (54.5%) than in those without HAT (32.0%) ( p = 0.008). In conclusion, the successful redo reconstruction under careful selection criteria saved the graft without retransplantation in 96.0% of the cases. Surgical revascularization should be preferentially considered for the management of HAT in adult living donor liver transplantation.

Portal vein reconstruction in pediatric liver transplantation using end-to-side jump graft: A case report.

Attenuated portal vein (PV) flow is challenging in pediatric liver transplantation (LT) because it is unsuitable for classic end-to-end jump graft reconstruction from a small superior mesenteric vein (SMV). We thus introduce a novel technique of an end-to-side jump graft from SMV during pediatric LT using an adult partial liver graft. We successfully performed two cases of end-to-side retropancreatic jump graft using an iliac vein graft for PV reconstruction. One patient was a 2-year-old boy with hepatoblastoma and a Yerdel grade 3 PV thrombosis who underwent split LT. Another patient was an 8-month-old girl who had biliary atresia and PV hypoplasia with stenosis on the confluence level of the SMV; she underwent retransplantation because of graft failure related to PV thrombosis. After native PV was resected at the SMV confluence level, an end-to-side reconstruction was done from the proximal SMV to an interposition iliac vein. The interposition vein graft through posterior to the pancreas was obliquely anastomosed to the graft PV. There was no PV related complication during the follow-up period. Using a jump vascular graft in an end-to-side manner to connect the small native SMV and the large graft PV is a feasible treatment option in pediatric recipients with inadequate portal flow due to thrombosis or hypoplasia of the PV.

Effects of an Antiadhesive Agent on Capsule Formation in Implant-Based Breast Reconstruction: A Randomized Controlled Trial.

BACKGROUND: Although implant-based breast reconstruction is a common surgical modality, a periprosthetic capsule inevitably forms and worsens in cases of postmastectomy radiation therapy. Previous animal studies have reported that antiadhesive agents (AAAs) inhibit periprosthetic capsule formation. The authors prospectively examined the clinical effects of an AAA (Mediclore) on capsule formation in implant-based breast reconstruction. METHODS: The authors analyzed patients who underwent immediate two-stage implant-based breast reconstruction following total mastectomy for breast malignancy between November of 2018 and March of 2019. Each patient was randomly allocated to the control or AAA group. After inserting the breast expander and acellular dermal matrix, AAA was applied around the expander before skin closure. The capsule specimen was obtained during the expander-implant change; capsule thickness and immunohistochemistry were investigated. RESULTS: A total of 48 patients were enrolled and allocated to the control ( n = 22) and AAA ( n = 26) groups. There were no significant differences in patient- and operation-related characteristics. Submuscular capsule thickness was significantly reduced in the AAA group compared with the control group. The levels of pro-capsular-forming cells (myofibroblasts, fibroblasts, and M1 macrophages) in the capsule were significantly lower in the AAA group than in the control group. CONCLUSIONS: AAA reduced the thickness of periprosthetic capsules and changed the profiles of cells involved in capsule formation during the tissue expansion. These findings demonstrate the clinical value of AAA for mitigating capsule formation in implant-based breast reconstruction. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Efficacy of retrograde innervation through the distal stump of the thoracodorsal nerve in single-stage neurovascular latissimus dorsi transfer for facial reanimation: A retrospective analysis of 30 cases.

The aim of the study was to analyze the efficacy of retrograde innervation of single-stage free latissimus dorsi (LD) flap for facial reanimation by the distal stump of thoracodorsal nerve (TDN). After the main trunk of TDN was split in half to preserve the function of transverse branch, the proximal stump was coapted with the contralateral facial nerve, and the distal stump was coapted with the ipsilateral masseteric nerve, or vice versa. The length of each nerve stump and the time required for voluntary and spontaneous muscle contraction after surgical treatment were reviewed. Among a total of 30 patients, there was no statistically significant difference in the successful recovery ratio of voluntary smile (antegrade, 86.7%; retrograde, 92.3%; p = 0.323) and of spontaneous smile (antegrade, 61.5%; retrograde, 100.0%; p = 0.079). There was no significant difference in the speed of nerve regeneration of voluntary smile (antegrade, 1.32 cm/month; retrograde, 1.14 cm/month; p = 0.213) and of spontaneous smile (antegrade, 0.91 cm/month; retrograde, 1.09 cm/month, p = 0.120). Within the limitations of the study, it seems that retrograde innervation of neurovascular muscle grafts has the potential to serve as a relevant alternative to other established options of neurovascular muscle transfer, because it provides comparable results in terms of rehabilitation success.

Effect of Stromal Vascular Fraction on Sustained Volume Retention of Five Different Hyaluronic Acid Fillers.

BACKGROUND: The technology of manufacturing hyaluronic acid (HA) fillers is evolving to increase their safety and durability. This study aimed to compare the volume maintenance effect of stromal vascular fraction (SVF) on different types of HA fillers. METHODS: In this controlled experiment, HA fillers mixed with SVF were injected into the right upper back and HA fillers alone were injected into the left upper back of each mouse. A total of 35 mice were separated into five groups according to the type of commercially used HA filler: Juvederm Voluma XC, Restylane Lyft, Restylane Skinboosters Vital, Giselle Ligne Signature 2, and Giselle Ligne Universal. Nodule size inspection was performed on post-injection days 0, 3, and 56. Ultrasonography for maximal two-dimensional area of filler nodule measurement and histology were performed on the last day of the inspection. RESULTS: While most of the groups showed a volume reduction of over 50% on day 56, regardless of SVF administration, significant volume maintenance was observed when Giselle Ligne Signature 2 was injected with SVF. Ultrasonographic measurement of two-dimensional filler nodule size showed no significant difference regarding filler types and SVF injection. When compared with the histological results of other fillers mixed with SVF, Giselle Ligne Signature 2 showed marked increase in cell survival and extracellular matrix components in HA particles. CONCLUSION: SVF showed different efficacies in terms of volume maintenance and cell survival for various HA filler types. The SVF mixture in selective HA filler injections may improve maintenance in clinical settings. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Revisional Medial Epicanthoplasty Using Reverse Z-Plasty Technique.

BACKGROUND: Medial epicanthoplasty is a common method for correcting epicanthal folds in Asians but sometimes cause unsatisfactory results. Although several procedural variations have been devised, revision techniques have earned little attention. The revision technique the authors have developed employs reverse Z-plasty to restore an overcorrected epicanthal fold. OBJECTIVES: The aim of this study was to investigate the effectiveness of the authors' reverse Z-plasty technique in restoring natural medial canthal region harmonizing with Asian face. METHODS: From January 2010 to December 2016, reverse Z-plasty was performed in patients seeking revisions after previous medial epicanthoplasties. Patients were surveyed to assess their satisfaction with surgical outcomes. Interepicanthal distance-lengthening ratios and symmetry of palpebral widths were evaluated digitally (ImageJ software) in patients who received revisional epicanthoplasty only. RESULTS: The reverse Z-plasty technique for revisional epicanthoplasty was performed in 548 Asian patients (83 males, 460 females). Most patients were pleased with the final outcomes. Only 6% submitted to later revisions of scars, which were otherwise scarcely visible after 3 months. Among 60 patients who underwent only revisional epicanthoplasty, interepicanthal distance-lengthening ratios ranged from 2.9% to 31.1% (average, 8.6%), and palpebral width symmetries improved. CONCLUSIONS: This particular technique helps restore the 3-dimensional appearance of medial canthal angle through horizontal skin and soft tissue (including muscle and ligament) restructuring, thus compensating for tissue deficiency. It is simple in design, easy to perform, and satisfactory results were achieved, conferring natural aesthetics to the medial canthal region.

Influence of Hypofractionated Versus Conventional Fractionated Postmastectomy Radiation Therapy in Breast Cancer Patients With Reconstruction.

PURPOSE: We aimed to compare breast-related complications between hypofractionated adjuvant postmastectomy radiation therapy (PMRT) and conventional fractionated radiation therapy (RT) in patients with breast cancer undergoing reconstruction by reconstruction surgery type. METHODS AND MATERIALS: Data from a total of 396 patients with breast cancer who underwent breast reconstruction after mastectomy between 2009 and 2018 were retrospectively reviewed. All patients received adjuvant PMRT according to either a conventional fractionation or hypofractionation schedule. We analyzed breast-related complications according to the timing of breast reconstruction (immediate or delayed). In cases of delayed reconstruction, only PMRT delivered before final delayed reconstruction was included. A major breast complication was defined as a breast-related toxicity that required reoperation or rehospitalization after the end of RT. RESULTS: The median follow-up time was 35.3 months (range, 8.8-122.7 months). Of all patients, 267 received immediate breast reconstruction and 129 received delayed breast reconstruction. In patients with immediate breast reconstruction, 91 were treated with conventional RT and 176 received hypofractionated RT. The occurrence of major breast-related complications did not differ significantly between the 2 fractionation regimens. Hypofractionated RT did not increase major wound problems (infection and dehiscence) compared with conventional RT. Furthermore, major contracture occurred significantly less frequently in hypofractionated RT. Of the patients who had delayed breast reconstruction, 48 received conventional RT and 81 received hypofractionated RT. There was no difference in the incidence of major breast complications between these 2 RT groups, and no difference in major breast complications were reported for either 1- or 2-stage delayed reconstruction. A time interval of >10 months between PMRT and final definitive reconstruction had a significantly lower incidence of major breast complications. CONCLUSIONS: Hypofractionated RT appears to be comparable with conventional fractionated RT in terms of breast-related complications in patients with breast cancer undergoing reconstruction, regardless of breast reconstruction type. An ongoing prospective randomized trial should confirm our findings.

The effect of delayed breast reconstruction after unilateral mastectomy on spine alignment.

BACKGROUND: Mastectomy in patients with breast cancer causes spinal deformities. We evaluated the effect of delayed breast reconstruction in post-mastectomy patients on spine alignments. METHODS: The study included 68 patients who underwent delayed breast reconstruction by three plastic surgeons in a single tertiary hospital. We measured proximal thoracic (PT), main thoracic (MT), and thoracolumbar (TL) Cobb angles and coronal spinal balance from chest or whole spine radiographs. RESULTS: The median changes in the PT and MT Cobb angles were -0.33 and -0.34 degrees, respectively. The change in TL Cobb angle and coronal spinal balance were only measured in 29 patients with available spine radiographs. The median change in TL Cobb angle and coronal spinal balance were -0.69 degrees and 3.75 mm, respectively. The median preoperative and postoperative PT Cobb angles were 1.75 and 1.24 degrees. The difference between preoperative and postoperative PT Cobb angles was statistically insignificant (P=0.036). The median preoperative and postoperative MT Cobb angles were 1.32 and 1.09 degrees, respectively. The difference between preoperative and postoperative MT Cobb angles was statistically insignificant (P=0.221). CONCLUSIONS: Delayed breast reconstruction did not result in clinically significant improvement in mastectomy-induced spinal deformity. This finding should be considered when choosing between immediate and delayed breast reconstruction.

Direct comparison of CGCRYODERM and DermACELL in the same patient for outcomes in bilateral implant-based breast reconstruction: a retrospective case series.

BACKGROUND: The use of acellular dermal matrix (ADM) has been popularized in implant-based breast reconstruction (IBR). However, it is still controversial if ADM-associated complication rates differ with varying types of ADM products. The aim of this study was to compare postoperative complications between CGCRYODERM and DermACELL. METHODS: A retrospective chart review was performed on 32 patients (64 breasts) who underwent bilateral prosthetic breast reconstruction between June 2015 and December 2019. All patients received two different ADMs in each breast during the surgery. Demographic variables, operative characteristics, and postoperative outcomes were compared between the cryopreserved and pre-hydrated ADM. RESULTS: The overall major and minor postoperative complications developed in 7 and 1 out of 32 patients, respectively. Seroma and infection were the most common complications. There were no cases that infection and/or seroma involved both breasts in one individual. No significant differences were observed in terms of seroma, infection, hematoma, mastectomy flap necrosis, or drainage period between the CGCRYODERM and DermACELL groups (P=0.5637, 0.1797, 1.0000, 0.3173, and 0.2925, respectively). There was no case of reconstruction failure leading to explantation. CONCLUSIONS: There were no statistically significant differences in postoperative complications between the two breasts reconstructed with CGCRYODERM and DermACELL in the same patient who underwent bilateral IBR. This is the first study to compare cryopreserved and pre-hydrated ADMs. We suggest that CGCRYODERM is a suitable option with a comparable safety profile for IBR.

Inhibition of SARS-CoV-2 Virus Entry by the Crude Polysaccharides of Seaweeds and Abalone Viscera In Vitro.

Much attention is being devoted to the potential of marine sulfated polysaccharides as antiviral agents in preventing COVID-19. In this study, sulfated fucoidan and crude polysaccharides, extracted from six seaweed species (Undaria pinnatifida sporophyll, Laminaria japonica, Hizikia fusiforme, Sargassum horneri, Codium fragile, Porphyra tenera) and Haliotis discus hannai (abalone viscera), were screened for their inhibitory activity against SARS-CoV-2 virus entry. Most of them showed significant antiviral activities at an IC50 of 12~289 µg/mL against SARS-CoV-2 pseudovirus in HEK293/ACE2, except for P. tenera (IC50 > 1000 µg/mL). The crude polysaccharide of S. horneri showed the strongest antiviral activity, with an IC50 of 12 µg/mL, to prevent COVID-19 entry, and abalone viscera and H. fusiforme could also inhibit SARS-CoV-2 infection with an IC50 of 33 µg/mL and 47 µg/mL, respectively. The common properties of these crude polysaccharides, which have strong antiviral activity, are high molecular weight (>800 kDa), high total carbohydrate (62.7~99.1%), high fucose content (37.3~66.2%), and highly branched polysaccharides. These results indicated that the crude polysaccharides from seaweeds and abalone viscera can effectively inhibit SARS-CoV-2 entry.

Diagnosis and management of toxic shock syndrome after breast reconstructive procedures with silicone implants.

Breast implant insertion is one of the most commonly used methods for breast reconstruction after total mastectomy. However, infection is a common postoperative complication of implant insertion. In most cases, these infections can be managed with antibiotics and supportive therapy. However, severe septic conditions, such as toxic shock syndrome (TSS), can sometimes occur. TSS is an extremely rare but life-threatening complication, for which early diagnosis and proper management play a crucial role in determining patients' outcome. Although only 16 cases of TSS after breast implant insertion have been reported in the literature, most of those cases involved a serious clinical course. The reason for the seriousness of the clinical course of TSS in these cases is that the initial impression and presentation of these patients are nonspecific, and patients can easily be misdiagnosed as having a simple upper respiratory infection, causing the underlying condition to be neglected. Herein, we present two patients who were diagnosed with TSS after receiving breast reconstruction surgery via a silicone implant after total mastectomy. Both patients were misdiagnosed at the initial examination since they showed no local infectious signs on the postoperative wound.

Comparison of irradiated and non-irradiated acellular dermal matrices in breast reconstruction under radiotherapy.

BACKGROUND: Acellular dermal matrices (ADMs) have become an essential material for implant-based breast reconstruction. No previous studies have evaluated the effects of sterility of ADM under conditions of radiation. This study compared sterile (irradiated) and aseptic (non-irradiated) ADMs to determine which would better endure radiotherapy. METHODS: Eighteen male Balb/C mice were assigned to the control group with no irradiation (group 1) or one of two other groups with a radiation intensity of 10 Gy (group 2) or 20 Gy (group 3). Both sterile and aseptic ADMs were inserted into the back of each mouse. The residual volume of the ADM (measured using three-dimensional photography), cell incorporation, α-smooth muscle actin expression, and connective tissue growth factor expression were evaluated. The thickness and CD3 expression of the skin were measured 4 and 8 weeks after radiation. RESULTS: In groups 2 and 3, irradiated ADMs had a significantly larger residual volume than the non-irradiated ADMs after 8 weeks (P<0.05). No significant differences were found in cell incorporation and the amount of fibrosis between irradiated and non-irradiated ADMs. The skin was significantly thicker in the non-irradiated ADMs than in the irradiated ADMs in group 3 (P<0.05). CD3 staining showed significantly fewer inflammatory cells in the skin of irradiated ADMs than in non-irradiated ADMs in all three groups after 4 and 8 weeks (P<0.05). CONCLUSIONS: Under radiation exposure, irradiated ADMs were more durable, with less volume decrease and less deposition of collagen fibers and inflammatory reactions in the skin than in non-irradiated ADMs.

Hypofractionated versus conventional fractionated radiotherapy for breast cancer in patients with reconstructed breast: Toxicity analysis.

PURPOSE: This study investigated whether hypofractionated adjuvant radiotherapy (RT) increased breast-related complication(s) compared to conventional fractionated RT in reconstructed breast cancer patients. METHODS: We conducted a retrospective review including 349 breast cancer patients who underwent immediate breast reconstruction following mastectomy or breast-conserving surgery (BCS) between 2009 and 2018 at two institutions. All patients were treated with adjuvant RT via either a conventional fractionated or hypofractionated regimen. We defined a major breast complication as a breast-related toxic event requiring re-operation or re-hospitalization during the follow-up period after the end of RT. RESULTS: The median follow-up was 32.3 months (4.8-118.5 months); 126 patients had conventional fractionated RT, and 223 patients received hypofractionated RT. In patients with mastectomy, there was no significant difference in the occurrence of any or major breast-related complications between the two fractionation regimens. In patients undergoing BCS, incidence of any breast complication showed no difference between two RT groups and no major breast complication was reported as well. Hypofractionated RT did not increase major wound problem (infection and dehiscence) compared to conventional RT. Incidence of major contracture was significantly lower in hypofractionated RT. CONCLUSIONS: There was no significant difference in the occurrence of any or major breast-related complications between the two different fractionation regimens, even in patients with mastectomy. Hypofractionated RT may be used comparable to conventional fractionated RT in terms of breast-related complications in reconstructed breast cancer patients. The prospective randomized trial would be necessary to clarify this issue.