Does the gene matter? Genotype-phenotype and genotype-outcome associations in congenital melanocytic naevi.

BACKGROUND: Genotype-phenotype studies can identify subgroups of patients with specific clinical features or differing outcomes, which can help shape management. OBJECTIVES: To characterize the frequency of different causative genotypes in congenital melanocytic naevi (CMN), and to investigate genotype-phenotype and genotype-outcome associations. METHODS: We conducted a large cohort study in which we undertook MC1R genotyping from blood, and high-sensitivity genotyping of NRAS and BRAF hotspots in 156 naevus biopsies from 134 patients with CMN [male 40%; multiple CMN 76%; projected adult size (PAS) > 20 cm, 59%]. RESULTS: Mosaic NRAS mutations were detected in 68%, mutually exclusive with BRAF mutations in 7%, with double wild-type in 25%. Two separate naevi were sequenced in five of seven patients with BRAF mutations, confirming clonality. Five of seven patients with BRAF mutations had a dramatic multinodular phenotype, with characteristic histology distinct from classical proliferative nodules. NRAS mutation was the commonest in all sizes of CMN, but was particularly common in naevi with PAS > 60 cm, implying more tolerance to that mutation early in embryogenesis. Facial features were less common in double wild-type patients. Importantly, the incidence of congenital neurological disease, and apparently of melanoma, was not altered by genotype; no cases of melanoma were seen in BRAF-mutant multiple CMN, however, this genotype is rare. CONCLUSIONS: CMN of all sizes are most commonly caused by mutations in NRAS. BRAF is confirmed as a much rarer cause of multiple CMN, and appears to be commonly associated with a multinodular phenotype. Genotype in this cohort was not associated with differences in incidence of neurological disease in childhood. However, genotyping should be undertaken in suspected melanoma, for guidance of treatment. What's already known about this topic? Multiple congenital melanocytic naevi (CMN) have been shown to be caused by NRAS mosaic mutations in 70-80% of cases, by BRAF mosaicism in one case report and by inference in some previous cases. There has been debate about genotypic association with different sizes of CMN, and no data on genotype-outcome. What does this study add? NRAS mosaicism was found in 68%, BRAF in 7% and double wild-type in 25% of cases of CMN. NRAS was the commonest mutation in all sizes of CMN, but was nearly universal in projected adult size > 60 cm. BRAF is often associated with a distinct multinodular clinical/histological phenotype. Adverse outcomes did not differ between genotypes on current numbers.

Melanoma in congenital melanocytic naevi.

Congenital melanocytic naevi (CMN) are a known risk factor for melanoma, with the greatest risk currently thought to be in childhood. There has been controversy over the years about the incidence of melanoma, and therefore over the clinical management of CMN, due partly to the difficulties of histological diagnosis and partly to publishing bias towards cases of malignancy. Large cohort studies have demonstrated that melanoma risk in childhood is related to the severity of the congenital phenotype. New understanding of the genetics of CMN offers the possibility of improvement in diagnosis of melanoma, identification of those at highest risk, and new treatment options. We review the world literature and our centre's experience over the last 25 years, including the molecular characteristics of melanoma in these patients and new melanoma incidence and outcome data from our prospective cohort. Management strategies are proposed for presentation of suspected melanoma of the skin and the central nervous system in patients with CMN, including use of oral mitogen-activated protein kinase kinase inhibitors in NRAS-mutated tumours.

Long-term aesthetics, patient-reported outcomes, and auricular sensitivity after microtia reconstruction: A systematic review.

BACKGROUND: Auricular reconstruction for microtia is most frequently performed using autologous costal cartilage (ACC) or porous polyethylene (PPE) implants. Short-term results are generally promising, but long-term results remain unclear. Long-term outcomes were explored in this systematic review, and minimal reporting criteria were suggested for future original data studies. METHODS: A systematic literature search was conducted in MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials from inception through October 14, 2020. Articles on auricular reconstruction in patients with microtia using ACC or PPE were included if postsurgical follow-up was at least 1 year. Outcome reporting was split into separate publications, and results on complications were reported previously. This publication focused on long-term aesthetic, patient-reported, and sensitivity outcomes. RESULTS: Forty-one publications reported on these outcomes. Both materials led to aesthetically pleasing results and high rates of patient satisfaction. ACC frameworks grew similarly to contralateral ears, and the anterior surface of auricles regained sensitivity. Furthermore, postoperative health-related quality of life (HRQoL) outcomes were generally good. Data synthesis was limited due to considerable variability between studies and poor study quality. No conclusions could be drawn on the superiority of either method due to the lack of comparative analyses. CONCLUSION: Future studies should minimally report (1) surgical efficacy measured using the tool provided in the UK Care Standards for the Management of Patients with Microtia and Atresia; (2) complications including framework extrusion or exposure, graft loss, framework resorption, wire exposure and scalp/auricular scar complications and (3) HRQoL before and after treatment using the EAR-Q patient-reported outcome measure (PROM).

Long-term complications of microtia reconstruction: A systematic review.

BACKGROUND: Microtia is a rare disorder characterized by malformation or even complete absence of the auricle. Reconstruction is often performed using autologous costal cartilage (ACC) or porous polyethylene implants (PPE). However, the long-term outcomes of both methods are unclear. OBJECTIVE: This systematic review aimed to analyze long-term complications and suggest minimal reporting criteria for future original data studies. METHODS: A systematic literature search was conducted in MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials from inception through October 14, 2020. Articles on auricular reconstruction in patients with microtia using ACC or PPE were included provided that the follow-up period was at least one year. This publication focused on long-term complications reported in patients with a postoperative follow-up period of at least one year. RESULTS: Twenty-nine publications reported on complications during long-term follow-up. Overall long-term complication rates were not reported. The incidence of individual complications during long-term follow-up was less than 10% after ACC reconstruction and less than 15% in PPE reconstruction. Framework resorption and wire exposure were reported even after an extended follow-up of more than five years after ACC reconstruction, while reports on the extended long-term results of PPE reconstruction are limited. Data synthesis was limited due to heterogeneity and poor study quality. CONCLUSIONS: Future studies should report on long-term complications including framework exposure or extrusion, graft loss, framework resorption, wire exposure and scalp and auricular scar complications. We recommend a surgical follow-up of at least five years.

Obstructive sleep apnoea in craniofacial microsomia: analysis of 755 patients.

A retrospective cohort study was set up to analyse the prevalence and treatment of obstructive sleep apnoea (OSA) in relation to the severity of the deformity in patients with craniofacial microsomia (CFM). This study included a population of 755 patients with CFM from three craniofacial centres. Medical charts were reviewed for severity of the deformity, types of breathing difficulty, age at which breathing difficulty first presented, treatment for OSA, and treatment outcome. In total, 133 patients (17.6%) were diagnosed with OSA. Patients with Pruzansky IIB/III classification or bilateral craniofacial microsomia were significantly more often diagnosed with OSA than unilaterally affected patients of Pruzansky I/IIA classification. The initial treatment of OSA consisted of adenotonsillectomy, tracheotomy, or non-invasive positive pressure ventilation. Thirty-seven patients received more than one treatment (range 1-3). In this study, the prevalence of OSA in patients with CFM was higher than the prevalence in the healthy population described in the literature. Although several treatment modalities are available for the treatment of OSA in patients with CFM, treatment should be individualized and based on clinical symptoms, the severity of the deformity, and comorbidities.

Acute bilateral forearm compartment syndrome of unknown aetiology.

This is the first reported case of non-traumatic, acute bilateral forearm compartment syndrome. Despite a delay of over 24 hours until surgical decompression and 50% muscle fibre necrosis in the histopathological examination, the clinical outcome was excellent after fasciotomy, delayed primary wound closure and early institution of a range of motion exercise programme. The literature on non-traumatic causes of compartment syndrome is reviewed.

Nanotechnology for Stimulating Osteoprogenitor Differentiation.

BACKGROUND: Bone is the second most transplanted tissue and due to its complex structure, metabolic demands and various functions, current reconstructive options such as foreign body implants and autologous tissue transfer are limited in their ability to restore defects. Most tissue engineering approaches target osteoinduction of osteoprogenitor cells by modifying the extracellular environment, using scaffolds or targeting intracellular signaling mechanisms or commonly a combination of all of these. Whilst there is no consensus as to what is the optimal cell type or approach, nanotechnology has been proposed as a powerful tool to manipulate the biomolecular and physical environment to direct osteoprogenitor cells to induce bone formation. METHODS: Review of the published literature was undertaken to provide an overview of the use of nanotechnology to control osteoprogenitor differentiation and discuss the most recent developments, limitations and future directions. RESULTS: Nanotechnology can be used to stimulate osteoprogenitor differentiation in a variety of way. We have principally classified research into nanotechnology for bone tissue engineering as generating biomimetic scaffolds, a vector to deliver genes or growth factors to cells or to alter the biophysical environment. A number of studies have shown promising results with regards to directing ostroprogenitor cell differentiation although limitations include a lack of in vivo data and incomplete characterization of engineered bone. CONCLUSION: There is increasing evidence that nanotechnology can be used to direct the fate of osteoprogenitor and promote bone formation. Further analysis of the functional properties and long term survival in animal models is required to assess the maturity and clinical potential of this.

MHC-class-II are expressed in a subpopulation of human neural stem cells in vitro in an IFNγ-independent fashion and during development.

Expression of major histocompatibility antigens class-2 (MHC-II) under non-inflammatory conditions is not usually associated with the nervous system. Comparative analysis of immunogenicity of human embryonic/fetal brain-derived neural stem cells (hNSCs) and human mesenchymal stem cells with neurogenic potential from umbilical cord (UC-MSCs) and paediatric adipose tissue (ADSCs), while highlighting differences in their immunogenicity, led us to discover subsets of neural cells co-expressing the neural marker SOX2 and MHC-II antigen in vivo during human CNS development. MHC-II proteins in hNSCs are functional, and differently regulated upon differentiation along different lineages. Mimicking an inflammatory response using the inflammatory cytokine IFNγ induced MHC-II up-regulation in both astrocytes and hNSCs, but not in UC-MSCs and ADSCs, either undifferentiated or differentiated, though IFNγ receptor expression was comparable. Together, hypoimmunogenicity of both UC-MSCs and ADSCs supports their suitability for allogeneic therapy, while significant immunogenicity of hNSCs and their progeny may at least in part underlie negative effects reported in some patients following embryonic neural cell grafts. Crucially, we show for the first time that MHC-II expression in developing human brains is not restricted to microglia as previously suggested, but is present in discrete subsets of neural progenitors and appears to be regulated independently of inflammatory stimuli.

Microvascular reconstruction of facial defects in settings where resources are limited.

The surgical treatment of defects caused by noma is challenging for the surgeon and the patient. Local flaps are preferred, but sometimes, because of the nature of the disease, there is not enough local tissue available. We describe our experience of free tissue transfer in Ethiopia. Between 2008 and 2014, 34 microsurgical procedures were done over 11 missions with the charity Facing Africa, predominantly for the treatment of defects caused by noma (n=32). The mean duration of operation was 442 minutes (range 200 - 720). Six minor wound infections were treated conservatively and did not affect outcome, a return to theatre was required in 4 patients with wound infections and one with a haemorrhage; 2 flaps failed and 2 partially failed, one patient developed an oronasal fistula, and one had an infection at the donor site that required a repeat graft. In settings where resources are limited, free flaps can be used when local tissue is not available and they cause less morbidity than pedicled tissue transfer.

Extensor tendon rehabilitation a prospective trial comparing three rehabilitation regimes.

Forty-two patients with 46 complete extensor tendon injuries were prospectively allocated to one of three rehabilitation regimes: static splintage; interphalangeal joint mobilization with metacarpophalangeal joint immobilization or; the "Norwich" regime. All 42 patients were operated on by one surgeon and assessed by one hand therapist. At 4 weeks the total active motion in the static splintage group was significantly reduced but by 12 weeks there was no difference between the regimes. There was no difference in total active motion between the repaired and uninjured hand at 12 weeks, with all patients achieving good or excellent results. However, grip strength at 12 weeks was significantly reduced compared to the uninjured hand after static splintage. There was no difference in hand therapy input between the regimes.

Total reconstruction of the nose in settings where resources are limited.

We describe a series of 8 patients who had total reconstruction of the nose during 4 separate missions to Ethiopia. The aetiology was noma (n=3), assault (n=2), acid burn (n=1), squamous cell carcinoma (n=1), and a sequela of meningococcal septicaemia (n=1). Reconstruction was with forehead flaps when adequate tissue was available (n=6) and with radial forearm flaps when it was not (n=2). Some reconstructive approaches require procedures to be done in stages, and in settings where resources are limited, difficulties with the continuity of care and provision for the management of complications, must be overcome.

A matter of identity - Phenotype and differentiation potential of human somatic stem cells.

Human somatic stem cells with neural differentiation potential can be valuable for developing cell-based therapies, including treatment of birth-related defects, while avoiding issues associated with cell reprogramming. Precisely defining the "identity" and differentiation potential of somatic stem cells from different sources, has proven difficult, given differences in sets of specific markers, protocols used and lack of side-by-side characterization of these cells in different studies. Therefore, we set to compare expression of mesenchymal and neural markers in human umbilical cord-derived mesenchymal stem cells (UC-MSCs), pediatric adipose-derived stem cells (p-ADSCs) in parallel with human neural stem cells (NSCs). We show that UC-MSCs at a basal level express mesenchymal and so-called "neural" markers, similar to that we previously reported for the p-ADSCs. All somatic stem cell populations studied, independently from tissue and patient of origin, displayed a remarkably similar expression of surface markers, with the main difference being the restricted expression of CD133 and CD34 to NSCs. Expression of certain surface and neural markers was affected by the expansion medium used. As predicted, UC-MSCs and p-ADSCs demonstrated tri-mesenchymal lineage differentiation potential, though p-ADSCs display superior chondrogenic differentiation capability. UC-MSCs and p-ADSCs responded also to neurogenic induction by up-regulating neuronal markers, but crucially they appeared morphologically immature when compared with differentiated NSCs. This highlights the need for further investigation into the use of these cells for neural therapies. Crucially, this study demonstrates the lack of simple means to distinguish between different cell types and the effect of culture conditions on their phenotype, and indicates that a more extensive set of markers should be used for somatic stem cell characterization, especially when developing therapeutic approaches.

Breast volume assessment: comparing five different techniques.

Breast volume assessment is not routinely performed pre-operatively because as yet there is no accepted technique. There have been a variety of methods published, but this is the first study to compare these techniques. We compared volume measurements obtained from mammograms (previously compared to mastectomy specimens) with estimates of volume obtained from four other techniques: thermoplastic moulding, magnetic resonance imaging, Archimedes principle and anatomical measurements. We also assessed the acceptability of each method to the patient. Measurements were performed on 10 women, which produced results for 20 breasts. We were able to calculate regression lines between volume measurements obtained from mammography to the other four methods: (1) magnetic resonance imaging (MRI), 379+(0.75 MRI) [r=0.48], (2) Thermoplastic moulding, 132+(1.46 Thermoplastic moulding) [r=0.82], (3) Anatomical measurements, 168+(1.55 Anatomical measurements) [r=0.83]. (4) Archimedes principle, 359+(0.6 Archimedes principle) [r=0.61] all units in cc. The regression curves for the different techniques are variable and it is difficult to reliably compare results. A standard method of volume measurement should be used when comparing volumes before and after intervention or between individual patients, and it is unreliable to compare volume measurements using different methods. Calculating the breast volume from mammography has previously been compared to mastectomy samples and shown to be reasonably accurate. However we feel thermoplastic moulding shows promise and should be further investigated as it gives not only a volume assessment but a three-dimensional impression of the breast shape, which may be valuable in assessing cosmesis following breast-conserving-surgery.

Prediction of cosmetic outcome following conservative breast surgery using breast volume measurements.

This study was undertaken to examine the feasibility of breast volume estimation as a predictor of cosmetic outcome. We looked at the cosmetic result of conservative surgery related to the percentage of breast tissue removed. The breast tissue excised was calculated by comparing the breast volume, calculated from the mammogram, and the specimen volume. A total of 24 patients were recalled to a special clinic and were assessed for their cosmetic result by the clinician, independent observer and the patient. The assessment was based on a scale of 1 to 4 (poor to excellent). Our results show that if less than 20% of the breast was removed, all assessors felt that the cosmetic result was at least fair. If more than 20% of the breast was removed, the cosmetic score was poor as assessed by the clinician and independent observer. When excision of greater than 20% of breast tissue is anticipated, then a breast reconstruction procedure should be considered, if cosmetic outcome is to be enhanced.

A prospective randomised clinical trial of the intra-operative use of 5-fluorouracil on the outcome of dupuytren's disease.

5-Fluorouracil reduces proliferation rates of fibroblasts, myofibroblast differentiation and contractility of ocular fibroblasts in vitro. This double-blind randomized clinical trial assesses whether intra-operative topical treatment with 5-fluorouracil reduces the recurrence rate after limited excision of Dupuytren's tissue. Patients with two-digit disease were randomized to having 5-fluorouracil (25mg/ml) treatment for 5 minutes on one digit and placebo on the other. Fifteen patients were enrolled with 18 months follow-up. There were no peri-operative complications. Wound healing was not delayed and there was no deterioration in the flexion deformity of the 5-fluorouracil treated digits. Patients were subsequently assessed by joint angle measurement at 3, 6, 12 and 18 months. There was no significant difference between control and 5-fluorouracil treated digits.

The outcome of drug smuggling by 'body packers'--the British experience.

Body packing or internal concealment used by drug dealers to smuggle illicit substances, puts the body packer at risk of both imprisonment and death. We report our experience over a 4 year period from January 1996 to December 1999 of suspects presenting to our hospital (the largest series in Europe). A total of 572 cases were assessed radiographically and 180 were shown to be carrying foreign bodies. The commonest reasons for admission were suspected overdose or gastrointestinal obstruction. Thirty-six cases were admitted, of whom 7 required surgical intervention. No deaths occurred. Of all people detained for smuggling by internal concealment into Britain during this period, 27% were seen in our hospital. These cases may present alone or escorted by Her Majesty's Customs and Excise personnel, and one must be aware of this possibility even when situated away from a port of entry.