Breast Reconstruction with a Tissue Engineering and Regenerative Medicine Approach (Systematic Review)

Current techniques for breast reconstruction include an autologous-tissue flap or an implant-based procedure, although both can impose further morbidity. This systematic review aims to explore the existing literature on breast reconstruction using a tissue engineering approach; conducted with the databases Medline and Embase. A total of 28 articles were included, mainly comprising of level-5 evidence with in vitro and animal studies focusing on utilizing scaffolds to support the migration and growth of new tissue; scaffolds can be either biological or synthetic. Biological scaffolds were composed of collagen or a decellularized tissue matrix scaffold. Synthetic scaffolds were primarily composed of polymers with customisable designs, adjusting the internal morphology and pore size. Implanting cells, including adipose-derived stem cells, with combined use of basic fibroblast growth factor has been studied in an attempt to enhance tissue regeneration. Lately, a level-4 evidence human case series was reported; successfully regenerating 210 mL of tissue using an arterio-venous pedicled fat flap within a tissue engineering chamber implanted on the chest wall. Further research is required to evaluate whether the use of cells and other growth factors could adjust the composition of regenerated tissue and improve vascularity; the latter a major limiting factor for creating larger volumes of tissue.

Abstract P3-12-15: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Yap J, Tamimi M, Griffin M, Stanley T, Steinman J, Chen W, Catalfamo F. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-12-15.

Computerised analysis of intrapartum fetal heart rate patterns and adverse outcomes in the INFANT trial

OBJECTIVE

To assess if a computerised decision support system reliably identified abnormal fetal heart rate (FHR) patterns in fetuses with adverse neonatal outcomes in the INFANT trial, and whether its use reduced substandard care.

DESIGN

Prospective cohort study within a randomised controlled trial.

SETTING

Twenty-four maternity units in the UK and Ireland.

POPULATION OR SAMPLE

A total of 46 614 labours between January 6 2010 and August 31 2013 in the INFANT trial.

METHODS

Panel review of intrapartum and neonatal care in infants with adverse outcome, and an assessment of the effectiveness of computerised interpretation of fetal heart rate in reducing substandard care. Descriptive analysis of other factors associated with adverse outcome.

MAIN OUTCOME MEASURES

Incidence and detection rate of abnormal fetal heart rate patterns, other characteristics associated with perinatal adverse outcome, and frequency of substandard care.

RESULTS

Computer interpretation of FHR patterns was deemed to be completely valid in only 24 of 71 (33.8%) cases of adverse outcome. On a scale of 0-10 (completely invalid to completely valid), 28 cases (39.4%) had a score of 6 or less, mainly due to lack of recognition of decelerations (15 cases), or reduced variability (seven cases), or failure to recognise tachysystole (five cases). There were multiple associated factors that modified the clinical assessment of FHR patterns. There was substandard care in 45/71 cases (63%).

CONCLUSION

A significant proportion of abnormal fetal heart rate patterns were not detected accurately by computer analysis, and its use did not reduce the incidence of substandard care.

FUNDING

UK National Institute for Health Research Health Technology Assessment Programme (project number 06.38.01).

TWEETABLE ABSTRACT

Improved recognition of abnormal fetal heart rate patterns is insufficient to reduce the incidence of substandard care.

Systematic review of methodologies used to assess mastectomy flap viability

BACKGROUND

Accurate prediction of mastectomy skin flap viability is vital as necrosis causes significant morbidity, potentially compromising results and delaying oncological management. Traditionally assessed by clinical judgement, a more objective evaluation can be provided using intraoperative imaging modalities. This systematic review aimed to compare all intraoperative techniques for assessment of mastectomy flap viability.

METHODS

A systematic literature review was performed using MEDLINE and Embase databases. Primary outcomes reported included specificity, sensitivity and predictive values of each test, and mean rates of mastectomy flap necrosis and reoperation. Secondary outcomes included cost analysis.

RESULTS

Some 18 studies were included. Designs were prospective cohort study (8), retrospective case series (4), prospective case series (3), retrospective case-control study (1), prospective pilot trial (1) and cost analysis study (1). The studies compared indocyanine green angiography (ICGA) (16 studies) and fluorescein dye angiography (FA) (3 studies) with clinical judgement. Sensitivity and specificity were highest for ICGA (5 studies) ranging from 38 to 100 and 68 to 91 per cent respectively. Both methods overpredicted necrosis. Mean rates of flap necrosis and reoperation decreased with ICGA (7·9 and 5·5 per cent respectively) and FA (3 and 0 per cent) compared with clinical judgement (19·4 and 12·9 per cent). Two studies were designed to define numerical parameters corresponding to perfusion using intraoperative techniques. Two studies performed a cost analysis for ICGA; one claimed a cost benefit and the other advocated its use in high-risk patients only.

CONCLUSION

ICGA and FA are potentially useful tools for mastectomy flap assessment. However, the predictive accuracy is subject to the specific settings and model of equipment used. Current recommendations support their use in high-risk patients.

Increase in Echogenicity of Echolucent Carotid Plaques after Treatment with Total Triterpenic Fraction of Centella asiatica: A Prospective, Placebo-Controlled, Randomized Trial

The aim of this study was to evaluate whether total triterpenic fraction of Centella asiatica (TTFCA), was effective in modulating collagen production over 12 months, by producing an increase in echogenicity in echolucent carotid plaques. Part I was a pilot study aimed at evaluating the effects of TTFCA on different types of plaques. Part II was a prospective, randomized, placebo-controlled trial aimed at evaluating the effects of TTFCA on hypoechoic-echolucent plaques. The sonographic examination of carotid plaques was made with high-resolution ultrasound. Capturing, digital image processing, and normalization were standardized, interobserver, intrascanner, gain-level variability were standardized using as reference blood (black) for the most echolucent parts of the plaque and the adventitia (white) as the most echogenic part. Normalization of echo texture was obtained and plaque characterization differentiated echo-texture of plaque associated with events and those that did not cause embolization, thrombosis, or cardiovascular events. After identifying plaques at higher risk, patients were treated with TTFCA (oral tablets, 60 mg, thrice daily for 12 months) to evaluate whether this compound, by modulating collagen synthesis, could increase the echogenicity and therefore the stability of echolucent plaques. Part II was aimed at evaluating the effects of TTFCA on hypoechoic-echolucent plaques. Asymptomatic patients with echolucent plaques (GSM < 18) were treated with TTFCA (60 mg, oral tablets three times daily for 12 months) or with comparable placebo after informed consent. All patients were also treated with antiplatelet agents. In part I, at inclusion the GSC in the hypoechoic group was 15 (range, 12–18) while in the hyperechoic group it was 26 (range, 24–31); at 6 months it was increased in the hypoechoic group and at 12 months the increase was significant (19.5; p<0.05). There was a minor increase in GSM in the hyperechoic group (30; ns). In part II in the treatment group there was a significant difference in GSM (increase) at 12 months (p<0.05), improvement in texture (p<0.05) and a nonsignificant decrease in stenosis. No changes were observed in the placebo group. Events were observed in 6.5% of patients in the TTFCA group and in 11% in the control group (p<0.05). In conclusion these observations suggest a positive action of TTFCA on the stabilization of hypoechoic, low-density carotid plaques.

Microcirculatory Effects of Total Triterpenic Fraction of Centella asiatica in Chronic Venous Hypertension: Measurement by Laser Doppler, TcPo2-co2, and Leg Volumetry

The aim of this prospective, randomized study was to demonstrate whether an oral preparation of TTFCA was effective in improving the microcirculation and edema (leg volume) in venous microangiopathy. Forty patients with venous hypertension were included. Treatment was prescribed for 6 weeks (tablets, 60 mg twice daily). Patients were randomized into a treatment and a placebo group. There were 20 patients in each group. In the treatment group the mean age was 42 (SD 7; M:F = 10:10); in the placebo group, the mean age was 40 (SD 9; M:F = 10:10). Tolerability and compliance were very good; there were no dropouts. At inclusion there were no differences between placebo and treatment group. After treatment there was a decrease in resting flux (29%) and an improvement (increase) in venoarteriolar response (52%); PO2 was increased (7.2%) and PCO2 decreased (9.6%). There was an important decrease in leg volume (66 mL decrease; 1.3% volume variation). The difference in flux, O2-CO2 and volume parameters were significant and clinically important at 6 weeks in the treatment group. In conclusion, TTFCA improves microcirculation and leg volume in venous hypertension. The effects of TTFCA are observed even in a limited sample of patients.

Capillary Filtration in Venous Hypertension: Evaluation with the Vacuum Suction Chamber Device and Strain-Gauge Plethysmography

The aim of this study was to evaluate local capillary filtration with the vacuum suction chamber (VSC) and the rate of ankle swelling (RAS) in patients with ankle edema due to venous hypertension before and after treatment with oral TTFCA (60 mg tablets twice daily) for 4 weeks. Strain-gauge plethysmography (SGP) was used to assess RAS and local capillary filtration was studied with the VSC (applied on the perimalleolar region); the disappearance of the weal was measured (minutes). Fifty patients with chronic venous insufficiency and edema were included (M:F = 25:25) after informed consent and randomized into a treatment (mean age 43; SD 7) and a control (mean age 44; SD 8) group. Compliance was very good (100% completed the 4-week trial); no side effects were observed. The two groups were comparable for age/sex distribution. Values of RAS and VSC time were comparable in the two groups, at inclusion. After 4 weeks there were no changes in the control group. A significant reduction was observed in the treatment (RAS decreased to 34% of the initial value; the VSC time decreased 48%; p<0.02). Treatment with TTFCA in chronic venous insufficiency is useful as soon as edema is detected to control the progressive alterations leading to ulcerations. This action is produced by complex actions on the microcirculation reducing and controlling edema and modulating collagen synthesis. This results in an improvement of the microcirculation, skin and subcutaneous tissue perfusion and functions.

Effects of the Total Triterpenic Fraction of Centella asiatica in Venous Hypertensive Microangiopathy: A Prospective, Placebo-Controlled, Randomized Trial

The aim of this study was to demonstrate whether total triterpenic fraction of Centella asiatica (TTFCA), was effective in improving the microcirculation in venous hypertension and microangiopathy. Forty patients with severe venous hypertension, ankle swelling, lipodermatosclerosis were included, After informed consent, patients were randomized into a treatment and a placebo group: those in the treatment group received TTFCA (tablets, 60 mg, twice daily for 8 weeks). The two groups of subjects were comparable for age and sex distribution. The mean age was 48 years (SD 9; M:F = 11:11) in the treatment group (22 patients) and 47.6 (SD 7; M:F = 10:8) in the placebo group (18 patients). There were no differences between placebo and treatment group at inclusion; there was no change between inclusion and measurements at 8 weeks in the placebo group. A decrease (p<0.05) in RF (flux at rest) and RAS (rate of ankle swelling) were observed in the treatment group. The decrease in capillary filtration was associated with improvement in signs and symptoms (p<0.05). The difference in flux, signs and symptoms, and filtration was clinically important at 8 weeks. No side effects were observed. In conclusion venous microangiopathy was improved by TTFCA treatment.

Modification of the Echogenicity of Femoral Plaques after Treatment with Total Triterpenic Fraction of Centella aslatica: A Prospective, Randomized, Placebo-Controlled Trial

The aim of this study was to evaluate whether TTFCA (total triterpenic fraction of Centella asiatica), was effective, by modulating collagen production, in a period of 12 months, increasing the echogenicity of echolucent plaques at the femoral bifurcation. Hypoechoic atherosclerotic plaques have been found to be associated with an increased evidence of cerebrovascular events. In this type of plaques stromal composition is limited as the collagen component is generally very low; the plaque composition is mainly due to lipid accumulation or thrombosis. The aim of this study was the evaluation of echogenicity of hyperechoic plaques and how it could be modified by a drug acting on the modulation of collagen synthesis. Antiplatelet agents were used in all patients; cholesterol-lowering agents were used in 34% of patients in the treatment group and in 36% in the placebo group. TTFCA was used at the dose of 60 mg thrice daily (oral tablets). Of the 60 included subjects 26 completed the study in the treatment group and 24 in the placebo group. At inclusion the average GSM in the treatment group was 14 (SD 3) and 14.3 (SD 3) in controls. At 12 months GSM was increased up to 22.8 (SD 4) in the treatment group and it was 15 (SD 3) in controls. Considering texture no significant changes were observed in controls while a qualitative increase in homogenicity was observed in the TTFCA group. Plaque size measured at the beginning and at the end of the study showed a median increase in size, in controls (23%; range 0%–44%); it was unchanged in the TTFCA group (variation 7%; 4%–26%). In conclusion in the treatment group plaques increased in echogenicity and in homogenicity; size and stenosis remained unchanged. Modulating the scarring process within echolucent plaques (low echogenicity, high echolucency, with a very low collagen/stromal component), possibly by collagen modulation, makes plaques more stable. This has been achieved and documented in the present study by an increase in the gray-scale median (plaques become more echogenic, more ‘white’). The variation in GSM is generally associated with a lower risk of wall thrombosis, rupture and embolization. These observations indicate a positive action of TTFCA on the stabilization of hypoechoic, low-density femoral plaques

Methods of Evaluation and Quantification of Microangiopathy in High Perfusion Microangiopathy (Chronic Venous Insufficiency and Diabetic Microangiopathy)

Noninvasive tests have been developed to provide qualitative and quantitative information that can offer answers to most questions posed in venous diseases. While duplex scanning is used to assess the macrocirculation, microcirculatory methods assess and quantify venous microangiopathy. Laser Doppler flowmetry is used to assess tissue viability and perfusion. Transcutaneous PO2 and PCO2 measurements are used to study venous hypertension, and strain-gauge plethysmography (SGP) is used to assess capillary filtration. In venous hypertension fluid filtration into the extracapillary compartment is increased. The increase in filtration is associated with a decreased venoarteriolar response. To quantify capillary filtration two methods have been developed: venous occlusion plethysmography and rate of ankle swelling. These methods quantify filtration into the extracapillary compartment and therefore are an indication of the formation of edema, which is the most frequent sign of venous hypertension. Other methods such as the vacuum suction chamber and the edema tester can be used to assess changes due to treatment in chronic venous hypertension. These methods have been used and validated in several experimental and clinical studies. The techniques described in this article were used in controlled environmental conditions. Results were consistent with clinical problems and data from previous studies from our group and from data from other investigators.

Predicting delivery of a small-for-gestational-age infant and adverse perinatal outcome in women with suspected pre-eclampsia

OBJECTIVE

To evaluate the test performance of 47 biomarkers and ultrasound parameters for the prediction of delivery of a small-for-gestational-age (SGA) infant and adverse perinatal outcome in women presenting with suspected pre-eclampsia.

METHODS

This was a prospective, multicenter observational study in which 47 biomarkers and ultrasound parameters were measured in 397 women with a singleton pregnancy presenting with suspected preterm pre-eclampsia between 20 + 0 and 36 + 6 weeks' gestation, with the objective of evaluating them as predictors of subsequent delivery of a SGA infant and adverse perinatal outcome. Women with confirmed pre-eclampsia at enrollment were excluded. Factor analysis and stepwise logistic regression were performed in two prespecified groups stratified according to gestational age at enrollment. The primary outcome was delivery of a SGA infant with a birth weight < 3^rd customized centile (SGA-3), and secondary outcomes were a SGA infant with a birth weight < 10^th customized centile and adverse perinatal outcome.

RESULTS

In 274 women presenting at 20 + 0 to 34 + 6 weeks' gestation, 96 (35%) delivered a SGA-3 infant. For prediction of SGA-3, low maternal placental growth factor (PlGF) concentration had a sensitivity of 93% (95% CI, 84-98%) and negative predictive value (NPV) of 90% (95% CI, 76-97%) compared with a sensitivity of 71% (95% CI, 58-82%) and a NPV of 79% (95% CI, 68-87%) for ultrasound parameters (estimated fetal weight or abdominal circumference < 10^th centile). No individual biomarker evaluated had a better performance than did PlGF, and marker combinations made only small improvements to the test performance. Similar results were found in 123 women presenting between 35 + 0 and 36 + 6 weeks' gestation.

CONCLUSION

In women presenting with suspected preterm pre-eclampsia, measurement of PlGF offers a useful adjunct for identifying those at high risk of delivering a SGA infant, allowing appropriate surveillance and timely intervention. © 2017 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.