Impact of adjuvant radiochemotherapy on free flap volume in head and neck reconstruction: A systematic review and meta-analysis

BACKGROUND

Limited data exist regarding the effect of adjuvant radiochemotherapy on free flap volume in head and neck reconstruction. However, an adequate free flap volume is an important predictor of functional and patient-reported outcomes in head and neck reconstruction.

METHODS

A systematic review of Medline, Embase, and the Cochrane Central Register of Controlled Trials was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. A total of 6710 abstracts were screened, and 36 full-text papers were reviewed. Nineteen studies met the inclusion criteria and were used to extract data for this analysis.

RESULTS

A meta-analysis of 14 two-arm studies comparing the impact of adjuvant radiotherapy versus no adjuvant radiotherapy was performed. The main analysis revealed that 6 months postoperatively, irradiated flaps showed a significant reduction of volume (average, 9.4%) compared to nonirradiated flaps. The average interpolated pooled flap volumes 6 months postoperatively were 76.4% in irradiated flaps and 81.8% in nonirradiated flaps. After a median postoperative follow-up of 12 months, the total flap volume was 62.6% for irradiated flaps and 76% for nonirradiated flaps. Four studies reported that chemotherapy had no significant impact on free flap volume.

CONCLUSIONS

Compared to nonirradiated flaps, irradiated flaps were significantly reduced in volume (range, 5% to 15.5%). Clinicians should take this into account when planning the surgical reconstruction of head and neck defects. Conducting large-scale prospective studies with standardized protocols and well-defined follow-up measurements could contribute to defining the ideal, personalized free flap volume for optimal function and patient-reported outcomes.

Impact of Adjuvant Radiotherapy on Free Flap Volume in Autologous Breast Reconstruction: A Scoping Review

In autologous breast reconstruction, a sufficient flap volume is fundamental to restore breast shape and ensure an aesthetic outcome. After mastectomy, postoperative irradiation is regularly indicated in the oncological treatment algorithm. When administering radiation therapy after autologous reconstruction, the tissue transferred is inherently irradiated. Although there is evidence that points to a reduction in flap volume after adjuvant radiotherapy, the data have been contradicting and inconclusive. To address this anecdotal evidence, we performed a scoping review of the current literature that addresses the effect of radiotherapy on breast flap volume. Six two-armed studies, comprising a total of 462 patients, reported on the effect of adjuvant radiotherapy on free flap volume changes. Of those, two studies found a significant negative impact of radiotherapy on free flap volume, while the other four studies did not. Reported flap volume changes ranged from no change to a reduction of 26.2%, measured up to two years postoperatively. The selected studies contain varying patient numbers, follow-up timepoints, types of flaps, and measuring methods, contributing to a relatively high heterogeneity. While we present some evidence suggesting a significant impact of adjuvant radiotherapy on breast flap volume, future studies are needed to further investigate this potential correlation.

Harnessing human adipose-derived stromal cell chondrogenesis in vitro for enhanced endochondral ossification

Endochondral ossification (ECO), the major ossification process during embryogenesis and bone repair, involves the formation of a cartilaginous template remodelled into a functional bone organ. Adipose-derived stromal cells (ASC), non-skeletal multipotent progenitors from the stromal vascular fraction (SVF) of human adipose tissue, were shown to recapitulate ECO and generate bone organs in vivo when primed into a hypertrophic cartilage tissue (HCT) in vitro. However, the reproducibility of ECO was limited and the major triggers remain unknown. We studied the effect of the expansion of cells and maturation of HCT on the induction of the ECO process. SVF cells or expanded ASC were seeded onto collagen sponges, cultured in chondrogenic medium for 3-6 weeks and implanted ectopically in nude mice to evaluate their bone-forming capacities. SVF cells from all tested donors formed mature HCT in 3 weeks whereas ASC needed 4-5 weeks. A longer induction increased the degree of maturation of the HCT, with a gradually denser cartilaginous matrix and increased mineralization. This degree of maturation was highly predictive of their bone-forming capacity in vivo, with ECO achieved only for an intermediate maturation degree. In parallel, expanding ASC also resulted in an enrichment of the stromal fraction characterized by a rapid change of their proteomic profile from a quiescent to a proliferative state. Inducing quiescence rescued their chondrogenic potential. Our findings emphasize the role of monolayer expansion and chondrogenic maturation degree of ASC on ECO and provides a simple, yet reproducible and effective approach for bone formation to be tested in specific clinical models.

Management of small (T1-T2) anal margin squamous cell carcinoma: clinical outcomes following local excision alone

AIM

Squamous cell carcinomas of the anus are normally treated with synchronous chemoradiotherapy (CRT). Small, localized anal margin tumours may be adequately treated by local excision (LE) alone. This study aims to investigate the outcomes of patients with anal margin tumours treated with LE alone, reserving the use of CRT for salvage on local recurrence (LR).

METHODS

Patients with small, localized (stage I/IIA) anal margin tumours treated by LE from October 1999 to September 2018 were identified. The effect of tumour size and resection margin on LR risk was analysed. Outcomes of overall survival and disease-free survival were measured.

RESULTS

Fifty-five patients with anal margin tumours were identified. Overall 5-year LR, overall survival and disease-free survival rates were 8%, 86% and 82% respectively. Of the seven LRs, five were successfully salvaged with CRT with no further recurrence and two were not fit for CRT. Resection margins in non-fragmented tumours and tumour size did not significantly influence LR risk.

CONCLUSIONS

Most small, localized anal margin tumours can be adequately treated by LE alone with low LR rates. Most patients who developed LR were salvaged using CRT, with no cancer-related deaths reported.

Profunda Artery Perforator Flap Tongue Reconstruction: An Effective and Safe Alternative to the Anterolateral Thigh Flap

BACKGROUND

The anterolateral thigh (ALT) perforator flap is a workhorse flap for tongue reconstruction. The authors present an alternative option using the profunda artery perforator (PAP) flap for glossectomy reconstruction compared to the ALT flap.

METHODS

A retrospective review was conducted of 65 patients who underwent subtotal or total glossectomy reconstruction between 2016 and 2020 (46 ALT vs. 19 PAP flaps). Flap volume was assessed using CT scans at two different time points. Quality of life and functional outcomes were measured using the MD Anderson Symptom Inventory for head and neck cancer (MDASI-HN).

RESULTS

Patients undergoing a PAP flap had significantly lower BMI compared to ALT flaps (22.7±5.0 vs. 25.8±5.1; p=0.014). Donor site and recipient site complications were similar as was the mean flap volume seven months after surgery (30.9% for ALT vs. 28.1% for PAP; p=0.93). Radiation and chemotherapy did not appear to have a significant effect on flap volume change over time. The most frequently reported high-severity items in MDASI-HN were swallowing/chewing and voice/speech for both cohorts. Patients who had reconstruction with a PAP flap had significantly better swallowing function (p=0.034).

CONCLUSION

Both the PAP and ALT flaps appear to be safe and effective choices for subtotal and total tongue reconstruction. The PAP flap can serve as an alternative donor site, especially in the setting of malnourished patients with thin lateral thigh thickness undergoing reconstruction of extensive glossectomy defects.

Innovative Strategies in Microvascular Head and Neck Reconstruction

The field of reconstructive microsurgery has witnessed considerable advancements over the years, driven by improvements in technology, imaging, surgical instruments, increased understanding of perforator anatomy, and experience with microsurgery. However, within the subset of microvascular head and neck reconstruction, novel strategies are needed to improve and optimize both patient aesthetics and post-operative function. Given the disfiguring defects that are encountered following trauma or oncologic resections, the reconstructive microsurgeon must always aim to innovate new approaches, reject historic premises, and challenge established paradigms to further achieve improvement in both aesthetic and functional outcomes. The authors aim to provide an up-to-date review of innovations in head and neck reconstruction for oncologic defects.

OUP accepted manuscript

Cells of the stromal vascular fraction (SVF) of human adipose tissue have the capacity to generate osteogenic grafts with intrinsic vasculogenic properties. However, cultured adipose-derived stromal cells (ASCs), even after minimal monolayer expansion, lose osteogenic capacity in vivo. Communication between endothelial and stromal/mesenchymal cell lineages has been suggested to improve bone formation and vascularization by engineered tissues. Here, we investigated the specific role of a subpopulation of SVF cells positive for T-cadherin (T-cad), a putative endothelial marker. We found that maintenance during monolayer expansion of a T-cad-positive cell population, composed of endothelial lineage cells (ECs), is mandatory to preserve the osteogenic capacity of SVF cells in vivo and strongly supports their vasculogenic properties. Depletion of T-cad-positive cells from the SVF totally impaired bone formation in vivo and strongly reduced vascularization by SVF cells in association with decreased VEGF and Adiponectin expression. The osteogenic potential of T-cad-depleted SVF cells was fully rescued by co-culture with ECs from a human umbilical vein (HUVECs), constitutively expressing T-cad. Ectopic expression of T-cad in ASCs stimulated mineralization in vitro but failed to rescue osteogenic potential in vivo, indicating that the endothelial nature of the T-cad-positive cells is the key factor for induction of osteogenesis in engineered grafts based on SVF cells. This study demonstrates that crosstalk between stromal and T-cad expressing endothelial cells within adipose tissue critically regulates osteogenesis, with VEGF and adiponectin as associated molecular mediators.

Evolution of a concept with enzymatic debridement and autologous in situ cell and platelet-rich fibrin therapy (BroKerF)

BACKGROUND

Deep partial-thickness burns are traditionally treated by tangential excision and split thickness skin graft (STSG) coverage. STSGs create donor site morbidity and increase the wound surface in burn patients. Herein, we present a novel concept consisting of enzymatic debridement of deep partial-thickness burns followed by co-delivery of autologous keratinocyte suspension and plated-rich fibrin (PRF) or fibrin glue.

MATERIAL AND METHODS

In a retrospective case study, patients with deep partial-thickness burns treated with enzymatic debridement and autologous cell therapy combined with PRF or fibrin glue (BroKerF) between 2017 and 2018 were analysed. BroKerF was applied to up to 15% total body surface area (TBSA); larger injuries were combined with surgical excision and skin grafting. Exclusion criteria were age <18 or >70 years, I°, IIa°-only, III° burns and loss of follow-up.

RESULTS

A total of 20 patients with burn injuries of 16.8% ± 10.3% TBSA and mean Abbreviated Burn Severity Score 5.45 ± 1.8 were identified. Of the patients, 65% (n = 13) were treated with PRF, while 35% (n = 7) were treated with fibrin glue. The mean area treated with BroKerF was 7.5% ± 0.05% TBSA, mean time to full epithelialization was 21.06 ± 9.2 days and mean hospitalization time was 24.7 ± 14.4 days. Of the patients, 35% (n = 7) needed additional STSG, 43% (n = 3) of whom had biopsy-proven wound infections.

CONCLUSION

BroKerF is an innovative treatment strategy, which, in our opinion, will show its efficacy when higher standardization is achieved. The combination of selective debridement and autologous skin cells in a fibrin matrix combines regenerative measures for burn treatment.

LAY SUMMARY

Patients suffering from large burn wounds often require the use of large skin grafts to bring burned areas to heal. Before the application of skin grafts, the burned skin must be removed either by surgery or using enzymatic agents. In this article, we describe a method where small areas of skin are taken and skin cells are extracted and sprayed on wound areas that were treated with an enzymatic agent. The cells are held in place by a substance extracted from patients' blood (PRF) that is sprayed on the wound together with the skin cells. We believe this technique can be helpful to reduce the need of skin grafts in burned patients and improve the healing process.

Case Report: Reconstruction of a Large Maxillary Defect With an Engineered, Vascularized, Prefabricated Bone Graft

The reconstruction of complex midface defects is a challenging clinical scenario considering the high anatomical, functional, and aesthetic requirements. In this study, we proposed a surgical treatment to achieve improved oral rehabilitation and anatomical and functional reconstruction of a complex defect of the maxilla with a vascularized, engineered composite graft. The patient was a 39-year-old female, postoperative after left hemimaxillectomy for ameloblastic carcinoma in 2010 and tumor-free at the 5-year oncological follow-up. The left hemimaxillary defect was restored in a two-step approach. First, a composite graft was ectopically engineered using autologous stromal vascular fraction (SVF) cells seeded on an allogenic devitalized bone matrix. The resulting construct was further loaded with bone morphogenic protein-2 (BMP-2), wrapped within the latissimus dorsi muscle, and pedicled with an arteriovenous (AV) bundle. Subsequently, the prefabricated graft was orthotopically transferred into the defect site and revascularized through microvascular surgical techniques. The prefabricated graft contained vascularized bone tissue embedded within muscular tissue. Despite unexpected resorption, its orthotopic transfer enabled restoration of the orbital floor, separation of the oral and nasal cavities, and midface symmetry and allowed the patient to return to normal diet as well as to restore normal speech and swallowing function. These results remained stable for the entire follow-up period of 2 years. This clinical case demonstrates the safety and the feasibility of composite graft engineering for the treatment of complex maxillary defects. As compared to the current gold standard of autologous tissue transfer, this patient’s benefits included decreased donor site morbidity and improved oral rehabilitation. Bone resorption of the construct at the ectopic prefabrication site still needs to be further addressed to preserve the designed graft size and shape.

Irinotecan and temozolomide chemotherapy in paediatric and adult populations with relapsed Ewing Sarcoma

BACKGROUND

Irinotecan and temozolomide (IT) is a widely used regimen for relapsed Ewing sarcoma (ES), although studies are largely limited to paediatric populations.

METHODS

We retrospectively reviewed paediatric (< 18 years) and adult patients (≥ 18 years) treated with salvage IT at two institutions. Haematologic toxicities were graded according to common terminology criteria of adverse events. Survival was estimated by the Kaplan-Meier method and compared by the Log Rank test.

RESULTS

Fifty-three patients were treated with IT from Jan, 2010 to Dec, 2018 (n = 16 paediatric; n = 37 adult). IT was given as second-line (n = 34; 64%) or ≥ third-line (n = 19; 36%). There was no difference in ≥ grade 3/4 haematologic toxicity between paediatrics and adults (31% vs. 35% respectively; p = 0.76). The frequency of diarrhoea of any grade was similar (38% in each group). Of 43 patients assessable for response, 12 (28%) had objective response (1 CR, 11 PR), 12 (28%) stable disease and 19 (44%) disease progression. Objective response rate did not differ between the two groups (36% in paediatrics vs. 25% in adults; p = 0.47). Median PFS was superior in paediatrics vs. adults (7.4 vs. 2.2 months, p = 0.039).

CONCLUSION

Irinotecan and temozolomide (IT) chemotherapy has activity for relapsed ES, with favourable toxicity and equally observed objective responses in the paediatric and adult populations. The observed superior PFS for the paediatric cohort requires further confirmation in future studies.

Platelet-rich plasma and stromal vascular fraction cells for the engineering of axially vascularized osteogenic grafts

Avascular necrosis of bone (AVN) leads to sclerosis and collapse of bone and joints. We have previously shown that axially vascularized osteogenic constructs, engineered by combining human stromal vascular fraction (SVF) cells and a ceramic scaffold, can revitalize necrotic bone of clinically relevant size in a rat model of AVN. For a clinical translation, the fetal bovine serum (FBS) used to generate such grafts should be substituted by a nonxenogeneic culture supplement. Human thrombin-activated platelet-rich plasma (tPRP) was evaluated in this context. SVF cells were cultured inside porous hydroxyapatite scaffolds with a perfusion-based bioreactor system for 5 days. The culture medium was supplemented with either 10% FBS or 10% tPRP. The resulting constructs were inserted into devitalized bovine bone cylinders to mimic the treatment of a necrotic bone. A ligated vascular bundle was inserted into the constructs upon subcutaneous implantation in the groin of nude rats. After 1 and 8 weeks, constructs were harvested, and vascularization, host cell recruitment, and bone formation were analyzed. After 1 week in vivo, constructs were densely vascularized, with no difference between tPRP- and FBS-based ones. After 8 weeks, bone formation and vascularization was found in both tPRP- and FBS-precultured constructs. However, the amount of bone and the vessel density were respectively 2.2- and 1.8-fold higher in the tPRP group. Interestingly, the density of M2, proregenerative macrophages was also significantly higher (6.9-fold) following graft preparation with tPRP than with FBS. Our findings indicate that tPRP is a suitable substitute for FBS to generate vascularized, osteogenic grafts from SVF cells and could thus be implemented in protocols for clinical translation of this strategy towards the treatment of bone loss and AVN.

Outcomes of extraskeletal vs. skeletal Ewing sarcoma patients treated with standard chemotherapy protocol

PURPOSE

To compare the outcomes of extraskeletal and skeletal Ewing sarcomas treated with standard chemotherapy protocol.

METHODS

We retrospectively collected data on primary localized skeletal and extraskeletal ES patients. Demographics and disease characteristics were compared between the two groups. The influence of presentation (skeletal vs. extraskeletal) on overall survival (OS) and local recurrence-free survival (LRFS) was assessed and compared by the log-rank test.

RESULTS

A total of 120 patients were included; 29 (24%) had extraskeletal and 91 (76%) had skeletal ES. All patients received vincristine, doxorubicin, and cyclophosphamide alternating with ifosfamide and etoposide (VDC-IE) chemotherapy, with a plan for local control at week 12. At a median follow-up of 38 months, there was no difference in OS between skeletal and extraskeletal ES; 5-year OS 70% and 67% respectively, p = 0.96. Patients with extraskeletal ES had inferior 5-year LRFS compared to skeletal ES; 74% vs. 83%; p = 0.042. Local recurrence occurred at a higher frequency in the extraskeletal group; 28% vs. 11%, p = 0.034, although more extraskeletal patients received adjuvant radiotherapy; 73% vs. 36%, p = 0.01. Among patients who underwent surgery (n = 76), there was no difference in R0 resection rate (skeletal: 89%, extraskeletal: 86%, p = 0.52, or good ( ≥ 90%) tumor necrosis; skeletal: 54%, extraskeletal: 38%, p = 0.31.

CONCLUSION

Patients with localized extraskeletal ES have comparable OS outcomes to patients with skeletal ES utilizing the standard VDC-IE chemotherapy. However, extraskeletal patients are at significantly higher risk for local recurrence.

P6134Understanding non-attendance to an inner city tertiary centre heart failure clinic: a pilot project

Background

Tackling health inequalities is a priority in heart failure (HF). We do not fully understand why some patients do not attend their hospital HF clinic appointments. Currently when a patient DNAs (does not attend) they are offered a repeat appointment often months later or are discharged from the service with a request to the primary care physician to re-refer. Non-attendance represents a missed opportunity to improve patients' health.

Purpose

The purpose of this pilot was to look at the demographics and patient factors that contribute to non-attendance. The aim is to understand and personalise our DNA policy to reduce health inequality, improve outcomes, and reduce inefficiencies in our service.

Methods

The last consecutive 45 patients who DNAd HF clinic were identified and for each, a patient who did attend the same clinic date (Attender), was chosen at random (random.org). The demographics were obtained (age, ethnicity, contact details) and medical notes reviewed (LVEF%, co-morbidities). The patient address was scored for its Index of Multiple Deprivation (IMD) – a UK government dataset measuring relative deprivation by ranking 32,844 neighbourhoods nationally using 37 indicators across 7 domains of deprivation where neighbourhood 1 is the most deprived nationally. Patients were phoned up to three times to establish the patient's mode, duration and cost of their last journey to clinic and, for those patients who DNAd, to ascertain the reason for non-attendance.

Results

Demographic and medical history was obtained for all patients. It was not possible to contact 2/45 of the Attenders, and 13/45 of the DNA patients. There was no significant difference in age, gender, number of comorbidities, LVEF%, travel time, or travel cost between DNAs and attenders. The mean one-way journey time was 53.4 mins (range 15–210 mins) and the mean return journey cost was GBP ≤10.95 (range ≤0–≤80). Common reasons for non-attendance were not receiving appointment details, forgetting appointments, being unwell on the day and difficulties with travel. The IMD score for the patients who DNAd was significantly lower confirming these patients lived in more deprived areas (9436±5863 vs. 15414±7801, p<0.001) with 71% of DNA patient's addresses in the bottom third most deprived neighbourhoods nationally.

Figure 1

Conclusions

There was a significant difference in deprivation score between patients who attended and DNAd their clinics. In addition, we found that all patients were travelling up to an hour each way to attend clinic, and that the cost of travel may be a barrier to attendance, even in a healthcare system that is free at the point of delivery. Despite calling three times, we were unable to speak to 29% of patients who DNAd and 4% of the patients who attended their appointments. Work is ongoing to reduce our DNA rates and personalise our response in this deprived population, with the aim of improving engagement and health inequality.

Reconstruction of Spinal Soft Tissue Defects With Perforator Flaps From the Paraspinal Region

BACKGROUND/AIM

Reconstruction of spinal soft tissue defects is challenging, especially when neural structures or prosthetic material are exposed. They should be covered with well-vascularized tissue such as paraspinal perforator flaps.

MATERIALS AND METHODS

This is a retrospective study of soft tissue reconstructions with paraspinal perforator flaps from 2011 to 2018. The technique is described and risk factors for poor wound healing were assessed. Postoperative complications are reported.

RESULTS

Twenty patients with a mean age of 63.65 years were included. Defects had an average size of 47 cm² and were mainly located in the lumbosacral region (9 patients). Twelve patients suffered from infection following spinal stabilization, seven of whom were diagnosed with osteomyelitis, two patients presented with pressure sore and one patient experienced wound dehiscence. One partial flap necrosis with a lumbar defect occurred, which required revision surgery. No total flap loss occurred. Stable, closed wounds were achieved at their final follow-up.

CONCLUSION

Perforator paraspinal flaps are suitable for immediate reconstruction of spinal defects.

Meta-analysis of surgical strategies in perforated left colonic diverticulitis with generalized peritonitis

PURPOSE

Surgical strategies for perforated diverticulitis (Hinchey stages III and IV) remain controversial. This systematic review aimed to compare the outcome of primary anastomosis, Hartmann procedure and laparoscopic lavage.

METHODS

A systematic literature search was conducted through Medline, Embase, Cochrane Central Register and Health Technology Assessment Database to identify randomized and non-randomized controlled trials involving patients with perforated left-sided colonic diverticulitis comparing different surgical strategies. The methodological quality of the included studies was assessed systematically (Grading of Recommendations, Assessment, Development and Evaluation) and a meta-analysis was performed.

RESULTS

After screening 4090 titles and abstracts published between 1958 and January 2018, 148 were selected for full text assessment. Sixteen trials (7 RCTs, 9 non-RCTs) with 1223 patients were included. Mortality rates were not significantly different between Hartmann procedure and primary anastomosis for Hinchey III and IV, neither in the meta-analysis of three RCTs (RR 2.03 (95% CI 0.79 to 5.25); p = 0.14, moderate quality of evidence) nor in the meta-analysis of six observational studies (RR 1.53 (95% CI 0.89 to 2.65); p = 0.13, very low quality of evidence). However, stoma reversal rates were significantly higher in the primary anastomosis group (RR 0.73 (95% CI 0.58 to 0.98); p = 0.008, moderate quality of evidence). Meta-analysis of four RCTs showed no significant difference between laparoscopic lavage for Hinchey III compared to sigmoid resection neither for mortality (RR 1.07 (95% CI 0.65 to 1.76); p = 0.79, moderate quality of evidence) nor for major complications (RR 0.86 (95% CI 0.69 to 1.08); p = 0.20, moderate quality of evidence).

CONCLUSIONS

This systematic review suggests similar rates of complications but higher rates of colonic restoration after primary anastomosis compared to Hartmann procedure in perforated diverticulitis with generalized peritonitis (Hinchey III and IV). Results in laparoscopic lavage for Hinchey III are not superior to primary resection. However, further studies with a careful interpretation of the meaning of re-interventions are required.

Engineered, axially-vascularized osteogenic grafts from human adipose-derived cells to treat avascular necrosis of bone in a rat model

BACKGROUND

Avascular necrosis of bone (AVN) leads to sclerosis and collapse of bone and joints. The standard of care, vascularized bone grafts, is limited by donor site morbidity and restricted availability. The aim of this study was to generate and test engineered, axially vascularized SVF cells-based bone substitutes in a rat model of AVN.

METHODS

SVF cells were isolated from lipoaspirates and cultured onto porous hydroxyapatite scaffolds within a perfusion-based bioreactor system for 5days. The resulting constructs were inserted into devitalized bone cylinders mimicking AVN-affected bone. A ligated vascular bundle was inserted upon subcutaneous implantation of constructs in nude rats. After 1 and 8weeks in vivo, bone formation and vascularization were analyzed.

RESULTS

Newly-formed bone was found in 80% of SVF-seeded scaffolds after 8weeks but not in unseeded controls. Human ALU+cells in the bone structures evidenced a direct contribution of SVF cells to bone formation. A higher density of regenerative, M2 macrophages was observed in SVF-seeded constructs. In both experimental groups, devitalized bone was revitalized by vascularized tissue after 8 weeks.

CONCLUSION

SVF cells-based osteogenic constructs revitalized fully necrotic bone in a challenging AVN rat model of clinically-relevant size. SVF cells contributed to accelerated initial vascularization, to bone formation and to recruitment of pro-regenerative endogenous cells.

STATEMENT OF SIGNIFICANCE

Avascular necrosis (AVN) of bone often requires surgical treatment with autologous bone grafts, which is surgically demanding and restricted by significant donor site morbidity and limited availability. This paper describes a de novo engineered axially-vascularized bone graft substitute and tests the potential to revitalize dead bone and provide efficient new bone formation in a rat model. The engineering of an osteogenic/vasculogenic construct of clinically-relevant size with stromal vascular fraction of human adipose, combined to an arteriovenous bundle is described. This construct revitalized and generated new bone tissue. This successful approach proposes a novel paradigm in the treatment of AVN, in which an engineered, vascularized osteogenic graft would be used as a germ to revitalize large volumes of necrotic bone.

The learning curve to achieve satisfactory completion rates in upper GI endoscopy: an analysis of a national training database

OBJECTIVE

The aim of this study was to determine the number of OGDs (oesophago-gastro-duodenoscopies) trainees need to perform to acquire competency in terms of successful unassisted completion to the second part of the duodenum 95% of the time.

DESIGN

OGD data were retrieved from the trainee e-portfolio developed by the Joint Advisory Group on GI Endoscopy (JAG) in the UK. All trainees were included unless they were known to have a baseline experience of >20 procedures or had submitted data for <20 procedures. The primary outcome measure was OGD completion, defined as passage of the endoscope to the second part of the duodenum without physical assistance. The number of OGDs required to achieve a 95% completion rate was calculated by the moving average method and learning curve cumulative summation (LC-Cusum) analysis. To determine which factors were independently associated with OGD completion, a mixed effects logistic regression model was constructed with OGD completion as the outcome variable.

RESULTS

Data were analysed for 1255 trainees over 288 centres, representing 243 555 OGDs. By moving average method, trainees attained a 95% completion rate at 187 procedures. By LC-Cusum analysis, after 200 procedures, >90% trainees had attained a 95% completion rate. Total number of OGDs performed, trainee age and experience in lower GI endoscopy were factors independently associated with OGD completion.

CONCLUSIONS

There are limited published data on the OGD learning curve. This is the largest study to date analysing the learning curve for competency acquisition. The JAG competency requirement for 200 procedures appears appropriate.

20 EFFECT OF PENICILLAMINE, HYPOTAURINE, AND EPINEPHRINE TREATMENT ON MOTILITY, HYPERACTIVITY AND ACROSOME REACTION OF RAM SPERMATOZOA

The aim of this study was to determine the effects of in vitro treatment of freshly ejaculated ram spermatozoa with different concentrations of penicillamine, hypotaurine, and epinephrine (PHE) at different incubation times on motility, hyperactivity (HA) and acrosome reaction (AR). Freshly ejaculated spermatozoa collected from three rams were pooled and then subjected to swim up technique in modified sperm Tyrode’s albumin lactate pyruvate (S-TALP) medium supplemented with different concentrations of PHE (0, 10, 20, 30, 40, 50, 75, and 100 mM). Following incubation (0, 1, 2, 3 and 4 h), sperm motility and hyperactivity were examined under the phase contrast microscope and acrosome reaction was detected by staining of the spermatozoa with silver nitrate. Results showed that treatment of spermatozoa with high concentrations of PHE (30, 40, 50, 75, and 100 mM) significantly increased the motility when compared with the control immediately after dilution (82.0, 82.0, 81.0, 82.0, 82.0 v.76.0%, respectively).This increase existed for the first and second hours of incubation. However, when the incubation time was increased for more than 2 h total motility significantly decreased (P < 0.05, ANOVA) as compared with the control. The same trend was observed in hyperactive motility. Treatment of spermatozoa with 50 and 75 mM of PHE for 1 h significantly increased the percentage of sperm with incomplete AR (20.0 and 27.0% respectively). At 4 h incubation, (49.0%) of spermatozoa treated with 75 mM PHE had undergone complete AR. Furthermore, the maximum value of total acrosome reaction (73.0%) was achieved at 4 h post incubation after addition of 75 mM PHE to ram sperm. In conclusion, under our experimental conditions, 75 mM PHE for 4 h was considered the best concentration of PHE for treatment of ejaculated ram spermatozoa for in vitro induction of acrosome reaction.

Untangling the Complexity of Liver Fluke Infection and Cholangiocarcinoma in NE Thailand Through Transdisciplinary Learning

This study demonstrates how a transdisciplinary learning approach provided new insights for explaining persistent Opisthorchis viverrini infection in northern Thailand, as well as elucidating problems of focusing solely on the parasite as a means of addressing high prevalence of cholangiocarcinoma. Researchers from diverse backgrounds collaborated to design an investigative homestay program for 72 Singaporean and Thai university students in five northeast Thai villages. The students explored how liver fluke infection and potential cholangiocarcinoma development are influenced by local landscape dynamics, aquatic ecology, livelihoods, food culture and health education. Qualitative fieldwork was guided daily by the researchers in a collaborative, co-learning process that led to viewing this health issue as a complex system, influenced by interlinked multidimensional factors. Our transdisciplinary experience has led us to believe that an incomplete understanding of these linkages may reduce the efficacy of interventions. Further, viewing liver fluke infection and cholangiocarcinoma as the same issue is inadvisable. Although O. viverrini infection is an established risk factor for the development of cholangiocarcinoma, multiple factors are known to influence the likelihood of acquiring either. Understanding the importance of the current livelihood transition, landscape modification and the resulting mismatch between local cultures and new socio-ecological settings on cholangiocarcinoma initiation and liver fluke transmission is of critical importance as it may help readjust our view of the respective role of O. viverrini and other socioeconomic risk factors in cholangiocarcinoma etiology and refine intervention strategies. As demonstrated in this study, transdisciplinary approaches have the potential to yield more nuanced perspectives to complex diseases than research that focuses on specific aspects of their epidemiology. They may therefore be valuable when designing effective solutions to context-sensitive diseases such as liver fluke infection and cholangiocarcinoma.

The effects of CCR5 inhibition on regulatory T-cell recruitment to colorectal cancer

BACKGROUND

Regulatory T cells (Treg) are enriched in human colorectal cancer (CRC) where they suppress anti-tumour immunity. The chemokine receptor CCR5 has been implicated in the recruitment of Treg from blood into CRC and tumour growth is delayed in CCR5-/- mice, associated with reduced tumour Treg infiltration.

METHODS

Tissue and blood samples were obtained from patients undergoing resection of CRC. Tumour-infiltrating lymphocytes were phenotyped for chemokine receptors using flow cytometry. The presence of tissue chemokines was assessed. Standard chemotaxis and suppression assays were performed and the effects of CCR5 blockade were tested in murine tumour models.

RESULTS

Functional CCR5 was highly expressed by human CRC infiltrating Treg and CCR5(high) Treg were more suppressive than their CCR5(low) Treg counterparts. Human CRC-Treg were more proliferative and activated than other T cells suggesting that local proliferation could provide an alternative explanation for the observed tumour Treg enrichment. Pharmacological inhibition of CCR5 failed to reduce tumour Treg infiltration in murine tumour models although it did result in delayed tumour growth.

CONCLUSIONS

CCR5 inhibition does not mediate anti-tumour effects as a consequence of inhibiting Treg recruitment. Other mechanisms must be found to explain this effect. This has important implications for anti-CCR5 therapy in CRC.

A pilot study of extralevator abdominoperineal excision for primary melanoma of the anorectum

Melanoma of the anorectum represents <2 % of all anorectal cancers and 0.3 % of all primary melanomas. Prognosis is poor, and optimal surgical management is controversial. This series details the surgical management of patients with anorectal melanoma presenting between 2002 and 2013 to the Queen Elizabeth Hospital in Birmingham, UK, a tertiary referral centre for colorectal disease. A retrospective review of patient notes, histology reports, and clinical letters was used to assess perioperative course and long-term outcome of all surgical methods. Eight patients with a median age of 65.5 presented with primary anorectal melanoma during the study period. Six cases were staged as T4 pre-operatively, with two referred as incompletely excised polyps. All eight patients underwent abdominoperineal excision of the rectum (APER), with the most recent four cases undergoing extralevator APER. Clear resection margins were achieved in three out of the four patients in the extralevator APER group with no nodal spread detected at histological assessment. Extralevator APER appears to be feasible and safe in the treatment of melanoma of the anorectum, with 75 % medium-term survival (median 38 months) in selected patients. As it is known that clear margins at surgery are associated with disease-free survival, the wider excision margin at the level of the pelvic floor offered by extralevator APER could result in more favourable surgical outcomes in this prognostically poor malignancy.

Evaluation of serum lysyl oxidase as a blood test for colorectal cancer

AIMS

Lysyl oxidase (LOX) expression is elevated in colorectal cancer (CRC) tissue and associated with disease progression. A blood test may form a more acceptable diagnostic test for CRC although LOX has not previously been measured in the serum. We therefore sought to determine the clinical usefulness of a serum LOX test for CRC in a symptomatic population.

METHODS

Adult patients referred to a hospital colorectal clinic with bowel symptoms completed a questionnaire and provided a blood sample for serum LOX measurement. Associations between presenting symptoms, serum LOX concentrations and outcomes of investigations were tested by univariate and multivariate analyses to determine if serum LOX was clinically useful in the prediction of CRC. LOX expression in CRC and adjacent colon biopsies was evaluated by ELISA and immunohistochemistry.

RESULTS

Thirty-one cases of colorectal cancer and 16 high-risk polyps were identified from a total of 962 participants. There was no association between serum LOX concentration and the presence of CRC, high-risk polyps or cancers at any site. LOX expression was significantly increased in CRC tissue compared to adjacent colon.

CONCLUSION

Despite overexpression of LOX in CRC tissue, elevated serum levels could not be demonstrated. Serum LOX measurement is therefore not a clinically useful test for CRC.

Patients newly diagnosed with ulcerative colitis receive earlier treatment in surgical clinics

AIM

The diagnosis and treatment of ulcerative colitis (UC) is traditionally the realm of gastroenterologists. However, the symptoms of UC overlap with those of bowel cancer and patients may be initially referred to colorectal surgery clinics. The aims of this study were to define which specialty most frequently diagnoses UC and to determine if there were differences in management between the two specialities.

METHOD

The demographics, presenting symptoms and clinical management of patients with newly diagnosed UC were determined and compared by speciality clinic of initial referral. Histopathology reports and clinic letters were reviewed to identify patients newly diagnosed with UC at a large university teaching hospital from January 2007 to January 2012.

RESULTS

Patients were more commonly referred to colorectal surgeons (74 vs 41 patients) than gastroenterologists. Patients referred to gastroenterology were younger (36.0 vs 59.6 years, P < 0.01) but there were no significant differences in gender, presenting symptoms or disease extent. Rigid sigmoidoscopy ± biopsy was more commonly performed in colorectal clinic (93.2 vs 31.7%, P < 0.01). There was a significantly shorter delay in starting disease-specific treatment for those patients referred initially to colorectal surgery (13.8 vs 33.6 days, P = 0.01). Performing rigid sigmoidoscopy in clinic was associated with starting disease-specific treatment at this visit.

CONCLUSION

Patients with first presentation UC are more commonly seen in colorectal surgery clinics where rigid sigmoidoscopy is more frequently undertaken, allowing earlier commencement of UC treatment.

[Usefulness and predictive value of PSA density, adjusted by transition zone volume, in men with PSA levels between 2 and 4 ng/ml]

OBJECTIVE

To assess the diagnostic significance of prostate-specific antigen (PSA), density (PSAD) accuracy, and PSAD adjusted by transition zone volume (PSATZD) in men with PSA levels between 2.0 and 4.0 ng/ml.

MATERIAL AND METHODS

Between 2000 and 2010, 138 men with PSA levels between 2 and 4.0 ng/ml underwent transrectal ultrasonography (TRUS) and 12-core prostate biopsy. Diagnostic accuracies for various cut-offs of PSAD and PSATZD were investigated according to subdivided PSA levels of 2.0 to 3.0 ng/ml and 3.1 to 4.0 ng/ml.

RESULTS

The detection rate of prostate cancer was 23,8% (32/134). The percentage of patients with extracapsular disease was 28.1% (10/32) and primary Gleason grade 4 or 5 was obtained in 8/32 (25%) patients. The transition zone volume and PSATZD in cancer cases were significantly different in comparison with those in non-cancer cases. The area under the receiver operating characteristic curve for PSATZD was significantly higher in comparison with that for PSAD in the same subdivided PSA ranges. The diagnostic efficiency for PSATZD was higher than that for PSAD. The diagnostic efficiency showed the highest value at the cut-off level for PSATZD of 0.23 and 0.28 in men with PSA levels of 2.0 to 3.0 ng/ml and 3.1 to 4.0 ng/ml, respectively.

CONCLUSIONS

The use of PSATZD cut-offs as a biopsy indication may reduce many unnecessary biopsies without missing most prostate cancer cases in the PSA range of 2.0 to 4.0 ng/ml.

[Bone mineral density change: comparison between prostate cancer patients with or without metastases and healthy men (a North African ethnic group)]

AIM

To evaluate total body bone mineral density and regional bone mineral density in patients with prostate cancer with and without metastases, and to correlate them with bone scintigraphy findings.

PATIENTS AND METHODS

135 patients with prostatic carcinoma and 50 healthy subjects were investigated with bone scintigraphy and dual-energy X-ray absorptiometry. The bone scintigraphic findings were classified as normal (score 0: n=55), abnormal but not typical for metastases (score 1: n=45), and typical pattern of metastases (score 2: n=35).

RESULTS

: The patients with bone metastases prostate cancer had significantly higher total bone mineral density and regional bone mineral density of trunk and pelvis than healthy controls and prostate cancer patients without bone metastases. There was a significant positive correlation between bone scan score and total bone mineral density and regional bone mineral density of trunk and pelvis (r=0.328; P<0.05; r=0.60; P<0.001; r=0.480; P<0.001, respectively).

CONCLUSION

Bone metastasis is a major cause of morbidity in prostatic cancer, bone loss during hormonal treatment is currently effective. Our results show that patients of prostate cancer with bone metastases have increased bone mineral density (BMD) in the pelvis and trunk, possibly because of a predominance of osteoblastic over osteolytic metastases demonstrated by (99m)Tc MDP bone scan.

Obstructive sleep apnoea hypopnea syndrome - an overview

Obstructive sleep apnoea hypopnoea syndrome (OSAHS) is a common cause of breathing-related sleep disorder, causing excessive daytime sleepiness. Common clinical features of OSAHS include snoring, fragmented sleep, daytime somnolence and fatigue. This article aims to provide a comprehensive review of the condition, including its management.

Iron deficiency anaemia and delayed diagnosis of colorectal cancer: a retrospective cohort study

AIM

The extent to which different referral pathways following a primary care diagnosis of iron deficiency anaemia (IDA) are associated with delay in diagnosis of colorectal cancer (CRC) was determined.

METHOD

Eligible patients aged 40 or more years, with IDA diagnosed in primary care, and a subsequent diagnosis of CRC, were studied retrospectively. Referral pathways were identified using the specialty of first recorded GP referral following IDA diagnosis. Differences in time to diagnosis of CRC were assessed by referral specialty. Differences in the proportion of cases referred before and after the re-issue of the NICE urgent referral guidelines for suspected lower gastrointestinal (GI) cancer were also assessed.

RESULTS

Of 628,882 eligible patients, 3.1% (n = 19,349) were diagnosed with IDA during the study period; 3.0% (n = 578) were subsequently diagnosed with CRC. Two hundred and fifty-nine (44.8%) patients had no recorded referral or a referral unrelated to anaemia or the GI tract. Only 35% (n = 201) of patients were referred to a relevant specialty. Median time to CRC diagnosis ranged from 2.5 months (referral to a relevant surgical specialty) to 31.9 months (haematology). Time to diagnosis was longer in patients referred to a medical compared with a relevant surgical specialty (P = 0.024). There was no significant difference in time to CRC diagnosis before and after the NICE guidelines were re-issued in 2005.

CONCLUSION

Significant differences exist between referral specialties in time to CRC diagnosis following a primary care diagnosis of IDA. Despite NICE referral recommendations, a significant proportion of patients are still not managed within recommended care pathways to CRC diagnosis.

HIV Associated Opportunistic Pneumonias

Opportunistic pneumonias are major causes of morbidity and mortality in HIV infected individuals. The majority of new HIV infections in Malaysia are adults aged 20 to 39 years old and many are unaware of their HIV status until they present with an opportunistic infection. HIV associated opportunistic pneumonias can progress rapidly without appropriate therapy. Therefore a proper diagnostic evaluation is vital and prompt empiric treatment of the suspected diagnosis should be commenced while waiting for the results of the diagnostic studies. Tuberculosis, Pneumocystis pneumonia (PCP) and recurrent bacterial pneumonias are common causes of AIDS-defining diseases and are discussed in this article.

A survey on the initial management of spontaneous pneumothorax

Spontaneous pneumothorax (SP) is a common medical condition but continues to be a frequent management problem among doctors. Despite the availability of guidelines on management of SP, studies have shown that the compliance with the guidelines is low. The various treatment options available in treating this condition further confuse doctors on the right approach in managing SP. The objective of this study is to investigate the awareness of the availability of these existing guidelines and to investigate how the doctors involved in the initial management of SP would manage this condition. A self completed questionnaire which included three case scenarios were distributed among doctors in two teaching university hospitals and two large Ministry of Health hospitals. This study showed that there is a lack of awareness of the existing guidelines even among the senior doctors and there is a variation in the initial management of SP. Therefore a locally produced guideline may be beneficial to standardise and improve the management of SP.

Fast targeted multidimensional NMR metabolomics of colorectal cancer

The study of small molecules in body fluids has become an important tool to monitor the state of biological organisms. Applications range from model studies using cell lines to applications where human body fluids are used to monitor disease states or drug responses. NMR spectroscopy has been an important tool for metabolomics although severe overlap of signals has limited the number of compounds, which can be unambiguously identified and quantified. Therefore, deconvolution of NMR spectra is one of the greatest challenges for NMR-based metabolomics. This has commonly been achieved by using multidimensional spectra that have the disadvantage of requiring significantly longer acquisition times. Recently, a number of methods have been described to record NMR spectra much faster. Here, we explore the use of Hadamard-encoded TOCSY spectra to simultaneously select multiple lines from crowded NMR spectra of blood serum samples to acquire pseudo-two-dimensional spectra in minutes which would otherwise require many hours. The potential of this approach is demonstrated for the detection of a signature for colorectal cancer from human blood samples.

Factors affecting attitudes toward colorectal cancer screening in the primary care population

Background:

Colorectal cancer (CRC) is a major cause of death in the United Kingdom. Regular screening could significantly reduce CRC-related morbidity and mortality. However, screening programmes in the United Kingdom have to date seen uptake rates of less than 60%. Attitudes towards screening are the primary factors determining patient uptake.

Methods:

A questionnaire was sent to people aged 50–69 years who were registered with general practices in the West Midlands. A total of 11 355 people (53%) completed the questionnaire. Multivariable logistic regression analyses were performed to identify those factors (gender, age, ethnicity, deprivation, number of symptoms, and their duration) that most strongly contributed to negative/positive attitudes in the primary care population.

Results:

Fourteen percent of respondents had a negative attitude towards screening. Men, older people, and those with Indian ethnic backgrounds were more likely to have negative attitudes toward screening, whereas people with Black-Caribbean ethnic background, people with multiple symptoms and those reporting abdominal pain, bleeding, and tiredness were more likely to have a positive attitude.

Conclusion:

Culturally relevant screening strategies should aim to increase knowledge of the symptoms and signs related to bowel cancer among South Asian ethnic groups in the United Kingdom. It is also important to find ways to increase the acceptability of screening among asymptomatic patients.