Evaluation of safety and operative time in tumescent-free robotic nipple-sparing mastectomy: a retrospective single-center cohort study.

Purpose: Tumescent in nipple-sparing mastectomy (NSM) has been reported to increase the risk of necrosis by impairing blood flow to the skin flap and nipple-areolar complex. At our institution, we introduced a tumescent-free robotic NSM using the da Vinci single-port system (Intuitive Surgical, Inc.). Methods: We conducted a retrospective analysis of patients who underwent tumescent-free robotic NSM between October 2020 and March 2023 at Asan Medical Center (Seoul, Korea). Clinicopathological characteristics, adverse events, and operative time were evaluated. Results: During the study period, 118 patients underwent tumescent-free robotic NSM. Thirty-one patients (26.3%) experienced an adverse event. Five patients (4.2%) were classified as grade III based on the Clavien-Dindo classification and required surgery. The mean total operative time was 467 minutes for autologous tissue reconstruction (n = 49) and 252 minutes for implants (n = 69). No correlation was found between the cumulative number of surgical cases and the breast operative time (P = 0.30, 0.52, 0.59 for surgeons A, B, C) for the 3 surgeons. However, a significant linear relationship (P < 0.001) was observed, with the operative time increasing by 13 minutes for every 100-g increase in specimen weight. Conclusion: Tumescent-free robotic NSM is a safe procedure with a feasible operative time and few adverse events.

Analysis of flap thickness to breast projection ratio correlating to body mass index and age in east Asian women: Considerations in flap selection in breast reconstruction.

BACKGROUND: Several alternative flaps have been introduced and used for autologous breast reconstruction. However, as body fat distribution is different among patients, the donor of choice for sufficient breast projection varies between patients. METHODS: Patients who underwent autologous breast reconstruction from Jan 2018 to Sep 2022 were included. Age, body mass index (BMI), smoking history and hypertension, and diabetes occurrence were collected as baseline demographic data. Breast projection with five types of flap thickness was measured based on computed tomography angiography. Analysis was performed for five major autologous flaps for breast reconstruction. RESULTS: A total of 563 patients were included in the study. The mean age of the patients was 47.4 ± 7.9 (standard deviation; SD) years. The mean BMI of the patients was 24.0 ± 3.4 kg/m2. Only the correlation between flap thickness to breast projection ratio and age in the PAP flap illustrated statistical significance (p = .039), but the correlation coefficient was quite low (r = -0.087). Slim patients who had lower BMIs (under 25 kg/m2) had significantly higher sufficient flap thickness for breast reconstruction than patients with higher BMIs over 25 kg/m2 in the profunda artery perforator (PAP) flap (p < .001), the lumbar artery perforator (LAP) flap (p < .001), and the superior gluteal artery perforator (SGAP) flap (p < .001). CONCLUSIONS: The deep inferior epigastric perforator flap provided sufficient thickness and was not usually affected by age and BMI. The PAP, LAP, and SGAP flaps tended to maintain the thickness of the flap even when BMI decreased, so they are advantageous for reconstruction in slim patients. This study contributes evidence in consideration of flap selection in autologous breast reconstruction.

Robot-Assisted Capsulectomy with Immediate Reimplantation in Breast Reconstruction.

SUMMARY: Recent reports have introduced robotic breast surgery for immediate breast reconstruction with an implant. However, relevant reports of robot-assisted breast reconstruction including capsulectomy are limited. Although capsulectomy lowers risk of capsular contracture and thus contributes to better aesthetic outcomes, total capsulectomy may have complications, such as injury to axillary structures or chest wall and overlying skin devascularization. To minimize the risk of injury, the authors used a robotic system with Da Vinci SP, which has freely movable arms and clear, magnified three-dimensional vision, for total capsulectomy. Compared with conventional procedures, robotic surgery has the critical advantage of minimal incision and concealed scars, contributing to positive aesthetic outcomes. This study suggests that robot-assisted capsulectomy is technically feasible and safe for patients undergoing breast reconstruction with immediate reimplantation.

A comparison of clinical outcomes of acellular dermal matrix with and without radiation sterilization process in immediate prepectoral direct-to-implant breast reconstruction.

BACKGROUND: Although there are many acellular dermal matrix (ADM) products, the sterilization process varies for each product. We compared the clinical outcomes of immediate prepectoral direct-to-implant (DTI) breast reconstruction with and without sterilization products. METHODS: This was a retrospective study of immediate prepectoral DTI breast reconstructions performed between 2018 and 2020. We classified patients depending on whether the used ADM products had undergone radiation sterilization and compared the patient demographics and surgical outcomes, including seroma, infection, mastectomy flap necrosis, capsular contracture, and implant failure. RESULTS: The study included 357 patients, 182 in the no-sterilization group and 179 in the sterilization group. The ADM size differed significantly between the no-sterilization and sterilization groups (122.7 cm2 vs. 145.4 cm2, respectively, P = 0.01). There were no significant differences in overall rates of complications between the two groups, including seroma (P = 0.28), infection (P = 0.63), mastectomy flap necrosis (P = 0.76), and capsular contracture (P = 0.76). However, implant failure from infection (0% vs. 3.4%, P = 0.01) and drainage amount (690.3 mL vs. 779.36 mL, P = 0.04) with similar removal days were significantly higher in the sterilization group. CONCLUSION: The authors demonstrated similar complication rates for seroma, infection, mastectomy flap necrosis, and capsular contracture. Whereas a bigger size of ADM was needed to cover a similar implant volume, and drain amount was higher in the sterilization group, the salvage rate from infection was higher in the no-sterilization group with a significant difference.

Conventional versus Robot-assisted Immediate Breast Reconstruction: Reconstructive Outcome and Patient-reported Outcome Measures (PROMs).

BACKGROUND: This study compared conventional and robot-assisted mastectomy and breast reconstruction. To the best of our knowledge, this study is the first to report the results of robot-assisted mastectomy and breast reconstruction as well as a comparison of patient-reported outcomes. METHOD: A retrospective study included 473 breasts of 423 patients who underwent conventional mastectomy and breast reconstruction and 164 breasts of 153 patients who underwent robot-assisted mastectomy and breast reconstruction from July 2019 to October 2021. Demographic and oncologic data, reconstructive outcomes, and patient-reported outcomes (BREAST-Q) were evaluated. The results of implant-based and autologous breast reconstruction were separately evaluated. RESULTS: Skin necrosis requiring surgical debridement occurred significantly more frequently in the conventional group (8.0%) than in the robot-assisted group (2.0%) in implant-based reconstruction (p=0.035). At 6-12 months, robot-assisted breast reconstruction showed a higher sexual wellbeing score for implant-based reconstruction and a higher physical wellbeing score for autologous breast reconstruction than conventional breast reconstruction according to the BREAST-Q questionnaire. CONCLUSION: Robot-assisted mastectomy and breast reconstruction was associated with less skin necrosis and better patient-reported outcomes (sexual wellbeing for implant-based reconstruction and physical wellbeing for autologous breast reconstruction) than the conventional option. Robotic surgery could be a good option for mastectomy and breast reconstruction.

Human-Mimic Submuscular and Premuscular Irradiated Rat Model: Histologic Characteristics of the Capsule Tissue in Contact with the Breast Implant.

Background: In this study, we established two rat models that mimic human submuscular and premuscular breast reconstruction. We analyzed the capsule formation according to surgical techniques and adjacent tissues, including the chest wall tissues, such as the ribs and acellular dermal matrices (ADMs) that come in contact with silicone implants. Methods: This study consisted of experiments on 12 Sprague-Dawley rats that underwent implant reconstruction using ADM. They were divided into two groups: rats that underwent dual-plane implantation (n = 6; group 1) and those that underwent premuscular implant insertion (n = 6; group 2). All rats were irradiated with 35 Gy of fractionated radiation. Three months after surgery, the histology and immunochemistry of the capsule tissues of the ADM, muscle, and chest wall were analyzed. Results: Overall capsule thickness was thicker in group 1. Based on the tissue in contact with the silicone implant, ADM had a thinner capsule, less inflammation, less fibrosis, and less vascularization than the muscle and chest wall tissues. Conclusions: This study described two rat models of clinically relevant implant-based breast reconstruction using a submuscular and premuscular plane, ADM, and irradiation. Overall, the premuscular implantation rat model was associated with a thinner capsule. The ADM in contact with the silicone implant, even after irradiation, had superior protection from radiation compared with the other tissues.

Analysis on the Difference between the Practical Brassiere Size and Real Breast Volume.

Background: Brassiere cup size is defined as the difference in chest circumference between the inframammary fold and the fullest part of the breast. However, a large number of women are not aware of the correct definition and are prone to wearing incorrectly-sized brassieres. In this report, the authors compared the cup size of worn brassieres and the actual measurement. Methods: This study was a retrospective review of patients who had undergone breast reconstruction operation between May 2020 and June 2021. All patients who visited the plastic surgery clinic for breast reconstruction were inquired about their cup size, and their breast circumferences were measured. The patient demographic information, ptosis grade, mastectomy specimen weight, measured breast circumference, and known cup size were analyzed. Results: Overall, 163 women were included. Notably, 92 of 163 patients (56.4%) were wearing a correctly-sized brassiere. Patients were more likely to wear a correctly-sized brassiere as the cup size became smaller. Moreover, patients with A-cup breasts tended to wear larger brassieres, whereas patients with B and C-cup breasts tended to wear smaller brassieres than their actual breast cup size. Conclusions: Approximately one in two women do not know their correct brassiere cup size. Women tend to wear a brassiere of the wrong size as their cup size becomes larger. Therefore, it is important for surgeons to be aware of their patient's brassiere wearing habit and their perception when a surgery, such as augmentation or reconstruction, is planned.

Safety of Augmenting Breast Volume in Direct-to-Implant Breast Reconstruction With Contralateral Breast Augmentation: Comparison With 2-Stage Reconstruction.

BACKGROUND: Direct-to-implant breast reconstruction is a standard method of implant-based reconstruction; however, the risk of skin necrosis and implant failure exists. During simultaneous contralateral augmentation, an implant larger than the resected tissue must be inserted to balance both sides, which may increase the risk of complications. This study examined the differences in the incidence of complications between the single-stage direct-to-implant reconstruction and 2-stage reconstruction when contralateral augmentation was performed simultaneously. METHODS: This study included 99 patients who underwent implant-based breast reconstruction with contralateral augmentation between 2012 and 2020. A retrospective chart review was conducted and the patients were divided into 2 groups: the single-stage reconstruction (n = 61) and 2-stage reconstruction (TSR, n = 38) groups. Demographic data and surgical and oncological information were collected. Complications including skin necrosis and reconstruction failure were investigated as the primary outcome. RESULTS: Implant volume and contralateral implant volume were significantly greater in TSR group than in the single-stage reconstruction group. There were no significant differences in the incidence of complications and reconstruction failure rates between both groups. The nipple-sparing mastectomy was the risk factor for complications. Furthermore, the risk factors for mastectomy skin necrosis were implant volume and differences in the volume of both implants. CONCLUSIONS: Single-stage reconstruction did not increase the risk of complications compared with TSR when implants that were larger than the resected tissue were inserted after mastectomy. Proper patient selection and selection of implants that are not excessively large could satisfy patients' cosmetic needs in a single operation.

The effect of intraoperative immersion solutions on acellular dermal matrix: Biofilm formation and mechanical property.

BACKGROUND: Acellular dermal matrix (ADM) is generally used on implant-based breast operations; However, it can increase surgical site infection. Many immersion solutions are applied to ADM, however, the most effective solution is unknown. The purpose of this study is to determine the effect of different solutions on the biofilm formation and mechanical properties of ADM. METHODS: Aseptic porcine-derived ADMs were immersed in 5 different solutions for 30 min; sterile normal saline, 10% povidone-iodine, 0.5% chlorhexidine, antibiotics (cefazolin, gentamicin, and vancomycin), and taurolidine. They are transferred to 10 ml suspension of methicillin-sensitive/resistant Staphylococcus aureus (MSSA/MRSA) or Staphylococcus epidermidis and an overnight culture was performed. After rinsing and sonication to obtain the biofilm on ADM, colony forming unit (CFU) was measured. In addition, the maximum load before ADM deformation and the elongation length of ADM at the start of the maximum load was determined. RESULTS: Regardless of strains, povidone-iodine, chlorhexidine, and taurolidine group had lower CFUs than the saline group with statistical significance. Meanwhile, the antibiotics group did not show statistical difference from the saline group. Moreover, only taurolidine group showed higher tensile strength (MRSA, p = 0.0003; S. epidermidis, p = 0.0023) and elongation length (MSSA, p = 0.0015) than the saline group. The antibiotics and chlorhexidine group yielded lower tensile strength and elongation length than the povidone-iodine and taurolidine groups. CONCLUSIONS: It was suggested that the 10% povidone-iodine or taurolidine solution is effective. In contrast, the antibiotics solution could be considered as an effective intraoperative solution.

Magnetic Resonance Imaging Surveillance Study of Silicone Implant-based Breast Reconstruction: A Retrospective Observational Study.

This study aimed to evaluate the results of magnetic resonance imaging (MRI) surveillance of implant-based breast reconstruction in patients with breast cancer. Methods: This retrospective observational study analyzed patients who underwent implant-based breast reconstruction and MRI surveillance by a single surgeon from March 2011 to December 2018, in a single center. All patients were informed about the recommendation of the Food and Drug Administration for MRI surveillance, and they choose to undergo MRI 3 years after surgery. Results: The compliance rate for MRI surveillance was 56.5% (169/299). MRI surveillance was performed at a mean of 45.8 (4.04 years) ± 11.5 months after surgery. One patient (0.6%) showed an abnormal finding of an intracapsular rupture of the silicone implant. Conclusions: MRI surveillance for implant rupture in implant-based breast reconstruction showed a low incidence of silent implant rupture (0.6%), whereas the compliance of MRI was relatively high (56.5%). These results raise questions about whether taking an MRI in 3-4 years is suitable for imaging surveillance of breast silicone implants. Screening recommendations should be more evidence-based, and more studies are needed to prevent unnecessary screening and patient burden.

Systematic literature review on impacts of COVID-19 pandemic and corresponding measures on mobility.

The unprecedented COVID-19 outbreak has significantly influenced our daily life, and COVID-19's spread is inevitably associated with human mobility. Given the pandemic's severity and extent of spread, a timely and comprehensive synthesis of the current state of research is needed to understand the pandemic's impact on human mobility and corresponding government measures. This study examined the relevant literature published to the present (March 2023), identified research trends, and conducted a systematic review of evidence regarding transport's response to COVID-19. We identified key research agendas and synthesized the results, examining: (1) mobility changes by transport modes analyzed regardless of government policy implementation, using empirical data and survey data; (2) the effect of diverse government interventions to reduce mobility and limit COVID-19 spread, and controversial issues on travel restriction policy effects; and (3) future research issues. The findings showed a strong relationship between the pandemic and mobility, with significant impacts on decreased overall mobility, a remarkable drop in transit ridership, changes in travel behavior, and improved traffic safety. Government implemented various non-pharmaceutical countermeasures, such as city lockdowns, travel restrictions, and social distancing. Many studies showed such interventions were effective. However, some researchers reported inconsistent outcomes. This review provides urban and transport planners with valuable insights to facilitate better preparation for future health emergencies that affect transportation. Supplementary Information: The online version contains supplementary material available at 10.1007/s11116-023-10392-2.

Difference in the Occurrence of Capsular Contracture According to Tissue Characteristics in an Irradiated Rat Model.

BACKGROUND: This study was performed to evaluate the hypothesis that capsule formation varies according to the radiation dose in muscle tissues; chest wall tissues, including the ribs; and acellular dermal matrices (ADM) that are in contact with the silicone implant. METHODS: In this study, 20 Sprague-Dawley rats underwent submuscular plane implant reconstruction using ADM. They were divided into four groups: an unradiated control group ( n = 5), nonfractionated radiation at a dose of 10 Gy ( n = 5), nonfractionated radiation at a dose of 20 Gy ( n = 5), and fractionated radiation at a dose of 35 Gy ( n = 5). Three months after surgery, hardness was measured, and histologic and immunochemical analyses of the capsule tissues of the ADM, muscle tissues, and chest wall tissues were analyzed. RESULTS: As the radiation dose increased, the silicone implant became harder, but no significant difference in capsule thickness according to the radiation dose was observed. Based on the tissue in contact with the silicone implant, ADM had a thinner capsule thickness than the muscle tissues, as well as less inflammation and less neovascularization compared with the other tissues. CONCLUSIONS: This study describes a new rat model of clinically relevant implant-based breast reconstruction using a submuscular plane and ADM with irradiation. The ADM in contact with the silicone implant, even after irradiation, was protected from radiation compared with the other tissues. CLINICAL RELEVANCE STATEMENT: These research results could support the use of ADM in implant-based breast reconstruction for prevention of the capsular contracture, even after radiation.

A Comparative Study of Wraparound versus Anterior Coverage Placement of Acellular Dermal Matrix in Prepectoral Breast Reconstruction.

BACKGROUND: Prepectoral direct-to-implant insertion (DTI) with acellular dermal matrix (ADM) is the currently preferred operation for breast reconstruction. There are different placements of ADM, which are largely classified as wraparound placement or anterior coverage placement. Because there are limited data comparing these two placements, this study aimed to compare the outcomes of these two methods. METHODS: This was a retrospective study of immediate prepectoral DTI breast reconstructions performed by a single surgeon between 2018 and 2020. Patients were classified depending on the ADM placement type used. Surgical outcomes and breast shape changes using nipple position during follow-up were compared. RESULTS: A total of 159 patients were included in the study, with 87 in the wraparound group and 72 in the anterior coverage group. Demographics were similar between the two groups, excluding ADM amount used (154.1 cm 2 versus 137.8 cm 2 ; P = 0.01). There were no significant differences in the overall rate of complications between the two groups, including seroma (6.90% versus 5.56%; P = 1.0), total drainage amount (762.1 mL versus 805.9 mL; P = 0.45), and capsular contracture (4.6% versus 1.39%; P = 0.38). The wraparound group had a significantly longer distance change than that of the anterior coverage group in the sternal notch-to-nipple distance (4.44% versus 2.08%; P = 0.03) and midclavicle-to-nipple distance (4.94% versus 2.64%; P = 0.04). CONCLUSIONS: Wraparound and anterior coverage placement of ADM in prepectoral DTI breast reconstruction showed similar complication rates, including seroma, drainage amount, and capsular contracture. However, wraparound placement can make the breast more ptotic in shape compared with anterior coverage placement. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Cadaveric Study for Safe Elevation of a Profunda Artery Perforator Flap: Anatomy of the Perforators and Obturator Nerves.

BACKGROUND: This cadaveric study aimed to describe the anatomy of the profunda artery perforators (PAPs). METHODS: In total, nine free cadavers with 18 upper thighs were dissected, 12 of which were from female cadavers, and 6 were from male cadavers. The average age of the cadavers was 84.7 ± 4.2 years. Dissection was performed to evaluate the anatomic position and characteristics of the femoral PAPs. The perforator distance from the gluteal sulcus, number of perforators, perforating muscles, diameter of the perforators, origin of the perforators, and number of nerves passing above and below the perforators were determined. RESULTS: The average number of perforators that penetrate the adductor magnus muscle was 2.5. The average distance from the origin of the perforators to the gluteal sulcus was 71.72 ± 28.23 mm. The average numbers of the obturator nerves passing above and below the perforator in the adductor magnus muscle were 1.3 (range, 0-4) and 0.7 (range, 0-2), respectively. CONCLUSION: The results provide a detailed anatomic basis for the PAP flap. The perforators of a PAP flap may be included in a flap with a transverse design. Sacrificing the small obturator nerves during dissection may not lead to significant donor site morbidity.

Development of Three-Dimensional Breast Scan and Measurement Application Using Laser Imaging Detection and Ranging Sensor on iPhone.

SUMMARY: Laser imaging detection and ranging (LiDAR) is a modern three-dimensional (3D) technology that uses a time-of-flight method based on the round-trip time of an infrared laser beam to detect the presence and features of objects. The iPhone 12 Pro is the first smart mobile device with built-in LiDAR sensors. The authors' team developed a software application based on iOS devices with built-in LiDAR sensors for 3D breast scanning and automatically analyzing the breast's geometric measurement. Breast geometry, including midclavicle-to-nipple distance, sternal notch-to-nipple distance, nipple-to-inframammary fold (IMF) distance, distance between nipples, and body circumference on nipple and IMF level were measured using the software application and tapeline. The relative technical error of measurement (rTEM) value was used to calculate the error ratios between the measurements acquired by the software application and those of the tapeline. Good rTEM values ranging from 2.99% to 5.19% were found in the midclavicle-to-nipple distance, sternal notch-to-nipple distance, distance between nipples, nipple-level circumference, and IMF-level circumference. However, there was a poor rTEM value greater than 10% in the nipple-to-IMF distance. The proposed software application using current iOS devices with built-in LiDAR sensors can provide an ideal 3D scanning system that has a low cost burden, good accuracy, portability, and ease of use.

Comparative Study of DIEP and PAP Flaps in Breast Reconstruction: Reconstructive Outcomes and Fat Necrosis.

BACKGROUND: This study compared the reconstructive outcomes and fat necrosis of the profunda artery perforator (PAP) flap with those of the deep inferior epigastric perforator (DIEP) flap. METHODS: Data on all DIEP and PAP flap breast reconstructions performed between 2018 and 2021 at Asan Medical Center were compared. The overall reconstructive outcomes and presence of fat necrosis were analyzed through ultrasound evaluation performed by a board-certified radiologist. RESULTS: The PAP (n = 43) and DIEP flaps (n = 99) were used to reconstruct 31 and 99 breasts, respectively. The average age of the patients in the PAP flap group (39.1 ± 7.3 years) was lower than in the DIEP flap group (47.4 ± 7.7 years), and the body mass index (BMI) of patients undergoing PAP flap reconstruction (22.7 ± 2.8 kg/m2) was lower than those undergoing DIEP flap reconstruction (24.3 ± 3.4 kg/m2). There was no total loss of both flaps. Donor site morbidity was higher in the PAP flap group (11.1%) compared with the DIEP flap (1.0%). The rate of fat necrosis was higher in the PAP flaps (40.7%) than in the DIEP flaps (17.8%) during ultrasound. CONCLUSION: In our study, we found that PAP flap reconstruction tended to be performed in patients who were younger with lower BMIs compared with the DIEP flap. Successful reconstructive outcomes were observed in both the PAP and DIEP flaps; however, a higher rate of necrosis was observed in the PAP flap compared with the DIEP flap.

Analysis of Perfusion in the DIEP Flap: Role of the Location of the Perforator, Umbilicus, and Midline Crossing-Over Vessel.

BACKGROUND: During breast reconstruction, predicting contralateral perfusion of the deep inferior epigastric artery perforator flap can help minimize tissue necrosis. This study aimed to quantify the area of contralateral perfusion and identify the factors affecting it. METHODS: A retrospective study was conducted on unilateral breast reconstructions with a single perforator-based deep inferior epigastric artery perforator flap, for the period of 2017 to 2019. Data on the distance between the perforator and the umbilicus, and the grade of the midline crossing-over vessel (G0, no vessel; G1, suspicious vessel; G2, definite vessel), were collected. Contralateral perfusion was estimated using intraoperative indocyanine green angiography, and the degree of contralateral circulation based on perforator location was assessed using a response surface methodology analysis. RESULTS: The study included 143 patients (G0, 62; G1, 45; and G2, 36). The average length of transverse contralateral flap perfusion (contralateral circulation area/vertical height of the flap) increased as the crossing-over vessel grade increased (G0, 62.96 ± 20.33 mm; G1, 71.69 ± 20.66 mm; and G2, 81.1 ± 19.32 mm; P = 0.0002). In the response surface methodology analysis, contralateral perfusion was the least when the perforator was located near the umbilicus (G0, within a 10-mm radius; G1, <10-mm transverse distance and 16- to 22-mm vertical distance; and G2, within a 20-mm radius). CONCLUSIONS: The umbilicus can interfere with contralateral perfusion; thus, a definite presence of a midline crossing-over vessel ensures robust contralateral perfusion. The results of this study can help surgeons select the optimal single perforator before surgery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

Loss to follow-up after direct-to-implant breast reconstruction.

Loss to follow-up is inevitable in retrospective cohort studies, and patients are lost to follow-up after direct-to-implant reconstruction despite annual follow-up recommendation. We analyzed more than 500 patients to analyze the rate of loss to follow-up to plastic surgery and to investigate the factors affecting it. A retrospective review of patients who underwent direct-to-implant reconstruction between July 2008 and August 2016 was performed. Loss to follow-up to plastic surgery was defined as a difference of ≥24 months between the total and plastic surgery follow-up. The rate of loss to follow-up and associated factors including patients' demographics, surgery-related variables, oncological data, and early and late complications were analyzed. Of 631 patients who underwent direct-to-implant reconstruction, 551 patients continued visiting the hospital for breast cancer-related treatment. Of the 527 patients who were eligible for the study, 157 patients (29.8%) were lost to plastic surgery follow-up. Surgery-related variables, early complications, cancer stage, and adjuvant therapies were not significantly different. Younger age was significantly associated with loss to follow-up in univariate analysis. However, logistic regression revealed that a long total follow-up period, distant metastasis, and absence of late elective complications were significant factors contributing to follow-up loss. Late elective complications such as malposition, capsular contracture, and mastectomy flap thinning were more common in the follow-up group (48%) than in the loss to follow-up group (22%). Follow-up loss after direct-to-implant reconstruction was not associated with specific demographic or surgery-related variables, and postoperative courses significantly affected the loss to follow-up.

Outcomes of smooth round implant-based immediate breast reconstruction: Long-term follow-up results.

The issue of breast implant-associated anaplastic large cell lymphoma in 2019 has resulted in the discontinuation of textured breast implants and resumption in the use of smooth round implants. However, in the field of breast reconstruction, long-term follow-up data for direct-to-implant reconstruction using smooth round implants is insufficient. This retrospective study aimed to evaluate the long-term outcomes of breast reconstruction using smooth round implants. This study included 185 patients (208 breasts) who underwent smooth round implant-based immediate breast reconstruction between 2007 and 2018. Their demographic information and surgical and oncological data were collected. Early (within 90 days) and late (after 90 days) complications, reoperations, implant maintenance, and the survival rate were analyzed to evaluate the long-term outcomes and identify the related factors. The mean follow-up period was 112.08 months. The most common early complications were skin necrosis (9.13%) and infection (3.85%). The factors influencing the development of early complications were the mastectomy specimen weight (237.14 ± 114.84 cc and 298.04 ± 141.53 cc for no complication and any complication, respectively; p = 0.0123) and implant volume (222.79 ± 77.76 cc and 264.48 ± 89.03 cc for no complication and any complication, respectively; p = 0.0082). The most common late complication was capsular contracture (13.46%). Approximately 91.35% of the implants were maintained during the follow-up period. The factors affecting the development of early complications and implant maintenance were the mastectomy specimen weight and implant volume. This study provides information on long-term follow-up results useful in cases where only smooth round implants are available, which can then serve as a basis for future related studies.

SLC3A2 and SLC7A2 Mediate the Exogenous Putrescine-Induced Adipocyte Differentiation.

Exogenous polyamines are able to induce life span and improve glucose homeostasis and insulin sensitivity. However, the effects of exogenous polyamines on adipocyte differentiation and which polyamine transporters mediate them have not been elucidated yet. Here, we identified for the first time that exogenous polyamines can clearly stimulate adipocyte differentiation through polyamine transporters, solute carrier family 3 member A2 (SLC3A2) and SLC7A1. Exogenous polyamines markedly promote 3T3-L1 adipocyte differentiation by increasing the intracellular lipid accumulation and the expression of both adipogenic and lipogenic genes in a concentration-dependent manner. In particular, exogenous putrescine mainly regulates adipocyte differentiation in the early and intermediate stages. Moreover, we have assessed the expression of polyamine transporter genes in 3T3-L1 preadipocytes and adipocytes. Interestingly, the putrescine-induced adipocyte differentiation was found to be significantly suppressed in response to a treatment with a polyamine transporter inhibitor (AMXT-1501). Furthermore, knockdown experiments using siRNA that specifically targeted SLC3A2 or SLC7A2, revealed that both SLC3A2 and SLC7A2 act as important transporters in the cellular importing of exogenous putrescine. Thus, the exogenous putrescine entering the adipocytes via cellular transporters is involved in adipogenesis through a modulation of both the mitotic clonal expansion and the expression of master transcription factors. Taken together, these results suggest that exogenous polyamines (such as putrescine) entering the adipocytes through polyamine transporters, can stimulate adipogenesis.