The empty pelvis syndrome: a core data set from the PelvEx collaborative

BACKGROUND

Empty pelvis syndrome (EPS) is a significant source of morbidity following pelvic exenteration (PE), but is undefined. EPS outcome reporting and descriptors of radicality of PE are inconsistent; therefore, the best approaches for prevention are unknown. To facilitate future research into EPS, the aim of this study is to define a measurable core outcome set, core descriptor set and written definition for EPS. Consensus on strategies to mitigate EPS was also explored.

METHOD

Three-stage consensus methodology was used: longlisting with systematic review, healthcare professional event, patient engagement, and Delphi-piloting; shortlisting with two rounds of modified Delphi; and a confirmatory stage using a modified nominal group technique. This included a selection of measurement instruments, and iterative generation of a written EPS definition.

RESULTS

One hundred and three and 119 participants took part in the modified Delphi and consensus meetings, respectively. This encompassed international patient and healthcare professional representation with multidisciplinary input. Seventy statements were longlisted, seven core outcomes (bowel obstruction, enteroperineal fistula, chronic perineal sinus, infected pelvic collection, bowel obstruction, morbidity from reconstruction, re-intervention, and quality of life), and four core descriptors (magnitude of surgery, radiotherapy-induced damage, methods of reconstruction, and changes in volume of pelvic dead space) reached consensus-where applicable, measurement of these outcomes and descriptors was defined. A written definition for EPS was agreed.

CONCLUSIONS

EPS is an area of unmet research and clinical need. This study provides an agreed definition and core data set for EPS to facilitate further research.

If speed is of the essence: rapid analysis of ambergris by APCI compact mass spectrometry

The use of atmospheric pressure chemical ionisation (APCI) compact mass spectrometry (CMS) was investigated for the analysis of jetsam and museum-archived ambergris and of ambergris components in perfumes. The data were compared with those from existing methods. Authentic samples of some individual ambergris constituents (ambrein, coprostanol, epicoprostanol and coprostanone), were also examined. Rapid APCI CMS was achieved using either a solids probe or a probe with solutions held in capillary melting point tubes. Interpretation is made of the spectra of the principal natural product components, the relative ion responses were measured and the elemental composition of key ions in the spectra confirmed using high resolution accurate mass APCI MS. Rapid analysis of ambergris by APCI CMS may prove to be a further convenient method of identifying ambrein, of measuring the relative ratios of ambrein and steroids in ambergris and even of quantifying the latter, with minimal sample preparation.

A systematic review of oncosurgical and quality of life outcomes following pelvic exenteration for locally advanced and recurrent rectal cancer

INTRODUCTION

Pelvic exenteration (PE) is now the standard of care for locally advanced (LARC) and locally recurrent (LRRC) rectal cancer. Reports of the significant short-term morbidity and survival advantage conferred by R0 resection are well established. However, longer-term outcomes are rarely addressed. This systematic review focuses on long-term oncosurgical and quality of life (QoL) outcomes following PE for rectal cancer.

METHODS

A systematic review of the PubMed®, Cochrane Library, MEDLINE® and Embase® databases was conducted, in accordance with the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. Studies were included if they reported long-term outcomes following PE for LARC or LRRC. Studies with fewer than 20 patients were excluded.

FINDINGS

A total of 25 papers reported outcomes for 5,489 patients. Of these, 4,744 underwent PE for LARC (57.5%) or LRRC (42.5%). R0 resection rates ranged from 23.2% to 98.4% and from 14.9% to 77.8% respectively. The overall morbidity rates were 17.8-87.0%. The median survival ranged from 12.5 to 140.0 months. None of these studies reported functional outcomes and only four studies reported QoL outcomes. Numerous different metrics and timepoints were utilised, with QoL scores frequently returning to baseline by 12 months.

CONCLUSIONS

This review demonstrates that PE is safe, with a good prospect of R0 resection and acceptable mortality rates in selected patients. Morbidity rates remain high, highlighting the importance of shared decision making with patients. Longer-term oncological outcomes as well as QoL and functional outcomes need to be addressed in future studies. Development of a core outcomes set would facilitate better reporting in this complex and challenging patient group.

Variation in outcome measurement and reporting in studies of pelvic exenteration for locally advanced and recurrent rectal cancer: a systematic review

AIM

There is increasing research interest in pelvic exenteration for locally advanced and recurrent rectal cancer. Heterogeneity in outcome reporting can prevent meaningful interpretation and valid synthesis of pooled data and meta-analyses. The aim of this study was to assess homogeneity in outcome measures in the current pelvic exenteration literature.

METHOD

MEDLINE, Embase, CENTRAL, CINAHL and Scopus databases were searched from 1990 to 25 April 2023 to identify studies reporting outcomes of pelvic exenteration for locally advanced or recurrent rectal cancer. All reported outcomes were extracted, merged with those of similar meaning and assigned a domain.

RESULTS

Of 4137 abstracts screened, 156 studies met the inclusion criteria. A total of 2765 outcomes were reported, of which 17% were accompanied by a definition. There were 1157 unique outcomes, merged into 84 standardized outcomes and assigned one of seven domains. The most reported domains were complications (147 studies, 94%), survival (127, 81%) and surgical outcomes (123, 79%). Resection margins were reported in 122 studies (78%): the definition of a clear resection margin was not provided in 45 studies (37%), it was unclear in 11 studies (9%) and not specified beyond microscopically 'clear' or 'negative' in 31 (28%). Measurements of 2, 1, 0.5 mm and any healthy tissue were all used to define R0 margins.

CONCLUSION

There is significant heterogeneity in outcome measurement and reporting in the current pelvic exenteration literature, raising concerns about the validity of comparative or collaborative studies between centres and meta-analyses. Coordinated international collaboration is required to define core outcome sets and benchmarks.

Patients Undergoing Systemic Anti-Cancer Therapy Who Require Surgical Intervention: What Surgeons Need to Know

As part of routine cancer care, patients may undergo elective surgery with the aim of long-term cure. Some of these patients will receive systemic anti-cancer therapy (SACT) in the neoadjuvant and adjuvant settings. The majority of patients, usually with locally advanced or metastatic disease, will receive SACT with palliative intent. These treatment options are expanding beyond traditional chemotherapy to include targeted therapies, immunotherapy, hormone therapy, radionuclide therapy and gene therapy. During treatment, some patients will require surgical intervention on an urgent or emergency basis. This narrative review examined the evidence base for SACT-associated surgical risk and the precautions that a surgical team should consider in patients undergoing SACT.

Fluorescence-guided surgery: comprehensive review

BACKGROUND

Despite significant improvements in preoperative workup and surgical planning, surgeons often rely on their eyes and hands during surgery. Although this can be sufficient in some patients, intraoperative guidance is highly desirable. Near-infrared fluorescence has been advocated as a potential technique to guide surgeons during surgery.

METHODS

A literature search was conducted to identify relevant articles for fluorescence-guided surgery. The literature search was performed using Medical Subject Headings on PubMed for articles in English until November 2022 and a narrative review undertaken.

RESULTS

The use of invisible light, enabling real-time imaging, superior penetration depth, and the possibility to use targeted imaging agents, makes this optical imaging technique increasingly popular. Four main indications are described in this review: tissue perfusion, lymph node assessment, anatomy of vital structures, and tumour tissue imaging. Furthermore, this review provides an overview of future opportunities in the field of fluorescence-guided surgery.

CONCLUSION

Fluorescence-guided surgery has proven to be a widely innovative technique applicable in many fields of surgery. The potential indications for its use are diverse and can be combined. The big challenge for the future will be in bringing experimental fluorophores and conjugates through trials and into clinical practice, as well as validation of computer visualization with large data sets. This will require collaborative surgical groups focusing on utility, efficacy, and outcomes for these techniques.

Long-term surgical complications following pelvic exenteration: Operative management of the empty pelvis syndrome

AIM

Pelvic exenteration (PE) has become the standard of care for locally advanced and recurrent rectal cancer. The high short-term morbidity reported from this procedure is well established; however, longer term complications of such radical surgery and their management have not been fully addressed. This study aimed to investigate the incidence, indications and outcomes of long-term (more than 90-day) reoperative surgery in this group of patients, with a focus on the empty pelvis syndrome (EPS).

METHODS

Clinical data were extracted from a prospectively maintained database, with additional data pertaining to indications, operative details and outcomes of reoperative surgery obtained from electronic medical records. Patients were excluded if reoperative surgery was endoscopic or radiologically guided, was for the investigation or treatment of recurrent disease, or was clearly unrelated to previous surgery.

RESULTS

Of 716 patients who underwent PE, 75 (11%) required 101 reoperative abdominal or perineal procedures, 52 (51%) of which were in 40 (6%) patients for complications of EPS. This group were more likely to have undergone a total PE (65% vs. 43%; P < 0.01) with either major bony (70% vs. 50%; P < 0.01) and/or nerve (40% vs. 25%; P = 0.03) resections at index exenteration. The patho-anatomy, surgical management and outcomes of these patients are described herein, considering separately complications of entero-cutaneous fistula, entero-perineal fistula, small bowel obstruction and local management of perineal wound complications.

CONCLUSION

Six per cent of PE patients will require re-intervention for the management of EPS. Reliable strategies for preventing EPS remain elusive; however, surgical management is feasible with acceptable short-term outcomes with the optimum strategy to be selected on an individual patient basis.

Minimum standards of pelvic exenterative practice: PelvEx Collaborative guideline

This document outlines the important aspects of caring for patients who have been diagnosed with advanced pelvic cancer. It is primarily aimed at those who are establishing a service that adequately caters to this patient group. The relevant literature has been summarized and an attempt made to simplify the approach to management of these complex cases.

Neoadjuvant treatment of advanced colonic cancer: a paradigm shift?

Neoadjuvant chemotherapy is an exciting and emerging field for colonic cancer treatment. This article reviews the evidence for such treatment and the role of of molecular testing in treatment selection.

Characterizations and comparison of low sulfur fuel oils compliant with 2020 global sulfur cap regulation for international shipping

The International Marine Organization 2020 Global Sulfur Cap requires ships to burn fuels with <0.50% S and some countries require <0.10% S in certain Sulfur Emission Control Areas but little is known about these new types of fuels. Using both traditional GC-MS and more advanced chromatographic and mass spectrometry techniques, plus stable isotopic, δ¹³C and δ²H, analyses of pristane, phytane and n-alkanes, the organic components of a suite of three 0.50% S and three 0.10% S compliant fuels were characterized. Two oils were found to be near identical but all of the remaining oils could be forensically distinguished by comparison of their molecular biomarkers and by the profiles of the heterocyclic parent and alkylated homologues. Oils could also be differentiated by their δ¹³C and δ²H of n-alkanes and isoprenoids. This study provides important forensic data that may prove invaluable in the event of future oil spills.

MV Wakashio grounding incident in Mauritius 2020: The world's first major spillage of Very Low Sulfur Fuel Oil

Very Low Sulfur Fuel Oils (VSLFO, <0.5% S) are a new class of marine fuel oils, introduced to meet recent International Maritime Organization regulations. The MV Wakashio was reported to have released 1000 t of VLSFO when it grounded on a reef in Mauritius on 25th July 2020. A field sample of oily residue contaminating the Mauritian coast was collected on 16th August 2020 and compared with the Wakashio fuel oil. Both oils were analyzed for organic and elemental content, and stable isotope ratios δ¹³C and δ²H measured. Comprehensive two-dimensional gas chromatography with high-resolution mass spectrometry was used to identify and compare biomarkers resistant to weathering. The aromatic content in the VLSFO was relatively low suggesting that the potential for ecosystem harm arising from exposure to toxic components may be less than with traditional fuel oil spills. The Wakashio oil spill is, to our knowledge, the first documented spill involving VLSFO.

Indications and outcomes for repeat cytoreductive surgery and heated intra-peritoneal chemotherapy in peritoneal surface malignancy

INTRODUCTION

Cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) is offered in specialist centres as a treatment for peritoneal surface tumours. Despite its demonstrated efficacy, intra-abdominal recurrence occurs in 31-57% of patients. The aim of this study is to review the early and long-term outcomes in patients who undergo repeat CRS/HIPEC.

MATERIALS AND METHODS

A retrospective review of a prospectively maintained database of patients who had undergone repeat CRS/HIPEC for appendiceal neoplasms and colorectal peritoneal metastases (CRPM) from 2003 to 2019 was performed at a single specialist centre. Data pertaining to both short term outcomes and survival were evaluated.

RESULTS

Of 1259 patients who had undergone CRS/HIPEC, 84(6.7%) underwent repeat surgery: 45(53.6%) had pseudomyxoma peritonei (PMP) secondary to low grade appendiceal mucinous neoplasms (LAMN), 21(25.0%) had appendix carcinoma and 18(21.4%) had CRPM. Demographics, intra-operative findings and short-term outcomes were comparable across tumour types and between procedures. Median (95% CI) interval between procedures was 22.7(18.9-26.6) months and was comparable between tumour types. Median (95%CI) overall survival was not reached for the cohort overall or for those with PMP, but was 61.0(32.6-89.4) months for those with appendix cancer and 76.9(47.4-106.4) months for CRPM (p=<0.001). Survival was favourable in the PMP group (HR [95%CI] 0.044 [0.008-0.262]; p = 0.000) and unfavourable in the CC2-3 at index CRS procedure group (HR [95%CI] 25.612 [2.703-242.703]; p = 0.005).

CONCLUSION

Our findings demonstrate that repeat cytoredutive surgery with HIPEC can result in favourable survival, especially for patients with PMP when complete cytoreduction is achieved at index operation. We recommend that detailed patient assessment is performed through an expert multidisciplinary team meeting (MDT).

Ambrein: a minor, but common constituent of mammalian faeces?

For nearly 200 years, the only natural source of the alcohol ambrein has been coproliths produced in about 1% of sperm whales and in related jetsam. However, the finding of ambrein in adipocere/faeces of human corpses, led us to hypothesise that ambrein might occur in the faeces of other mammals. Herein, we used a recently developed gas chromatography-mass spectrometry method, with suitable derivatisation of the hindered hydroxy group of ambrein, to screen a number of extracts of mammalian faeces. Minor proportions of ambrein were detected in digested human sewage sludge and in the dung of elephant, domestic cattle, giraffe and buffalo. Whether ambrein formation in the terrestrial species is associated with coprolith formation, is unknown, but solid deposits known as enteroliths and fecaliths occur in humans and some domestic animals.

Critical considerations for targeting colorectal liver metastases with nanotechnology

Colorectal cancer remains a significant cause of morbidity and mortality worldwide. Half of all patients develop liver metastases, presenting unique challenges for their treatment. The shortcomings of conventional chemotherapy has encouraged the use of nanomedicines; the application of nanotechnology in the diagnosis and treatment of disease. In spite of technological improvements in nanotechnology, the complexity of biological systems hinders the prospect of nanomedicines being applied in cancer therapy at the present time. This review highlights current biological barriers and discusses aspects of tumor biology together with the physicochemical features of the nanocarrier, that need to be considered in order to develop effective nanotherapeutics for colorectal cancer patients with liver metastases. It becomes clear that incorporating an interdisciplinary approach when developing nanomedicines should assure appropriate disease-driven design and that this will form a critical step in improving their clinical translation. This article is characterized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Biosynthesis of ambrein in ambergris: evidence from isotopic data and identification of possible intermediates

Ambrein is found in ambergris, a coprolith occurring in the rectum of the sperm whale. In vitro, ambrein is produced by enzymatic cyclisation of squalene, via a monocyclic intermediate. However, little is known of the in vivo process. In order to find evidence for the reaction in vivo, a comparison was made of the δ¹³C relative isotopic ratios of ambrein in ambergris with those of co-occurring sterols. A statistically significant difference was noted. This suggests that ambrein originates via a different biosynthetic mechanism from that of the sterols. Examination of the minor constituents of a hydrogenolysed extract of ambergris revealed compounds with a bicyclic polypodane nucleus, rather than those with monocyclic structures. It is hypothesised that in vivo biosynthesis of ambrein proceeds, at least in some cases, via bacterial production of bicyclic polypodenols. The latter are known products of non-concerted squalene (or squalene oxide) cyclisations in other organisms.

Evaluating unmet needs in patients undergoing surgery for colorectal cancer: a patient reported outcome measures study

AIM

Patient reported outcome measures (PROMs) are self-reported measures of patients' health status or health-related quality of life at a single point in time. We aimed to evaluate the use of a colorectal PROM and conducted a focus group to further explore this and other unmet needs in our patient population treated surgically for colorectal cancer.

METHOD

A multidisciplinary research group consisting of colorectal surgeons, nurse specialists, psychologists, sociologists and patient representatives devised a composite tool of new and existing outcome measures which was piloted in our local population (n = 35). Participants were subsequently invited to attend a semi-structured focus group during which the PROM was reviewed and an unmet needs analysis was performed. Thematic analysis of focus group transcripts was undertaken for emergent themes.

RESULTS

Initial consensus was for a tool including the EQ-5D, Functional Assessment of Cancer Therapy - Colorectal (FACT-C), the distress thermometer, a validated measure of stigma, an unmet needs analysis, and questions assessing the psychological impact of cancer. Median and interquartile range values suggested that all metrics were discriminatory with the exception of FACT-C. All participants agreed that the tool was acceptable and reflected the current state of their health and emotions. Thematic analysis of focus group transcripts identified four major themes: physical symptoms, emotional response, information provision and coping mechanisms.

CONCLUSION

Through expert consensus, local piloting and patient focus groups we have evaluated a novel PROM for colorectal cancer. Furthermore, through our direct engagement with patients we have identified several unmet needs which we are currently exploring within the clinical service.

Volatile and semi-volatile components of jetsam ambergris

Volatile and semi-volatile compounds account for the odors, long valued in the perfumery industry, of the natural product, ambergris. Here we demonstrate application of solid phase micro extraction (SPME) and gas chromatography-mass spectrometry (GC-MS) to headspace analysis of the volatiles and semi-volatiles of jetsam ambergris. The samples collected in 2017/2018, ranged from a black, sticky material from New Zealand, likely recently ejected from a sperm whale, to a white solid found on a beach in Chile and radiocarbon-dated previously to be about 1000 years old. The traces of volatile/semi-volatile compounds extracted included, odorous γ-dihydroionone and odor-free pristane (2,6,10,14-tetramethylpentadecane), as the major constituents. The ratios of these to one another and to many other minor constituents, varied, depending on sample color and age.

Awareness of surgical expenditure amongst UK trainees and consultants: A questionnaire study

INTRODUCTION

Limited knowledge of surgical device and service costs restricts a surgeon's ability to make cost efficient choices and contribute to the efficiency savings required by the NHS to reduce the financial deficit. This study aims to assess how aware surgeons are of surgical equipment and regularly used services.

METHODS

A single sided hard copy questionnaire asking for the estimate cost of 24 surgical devices/services was handed out to individuals at two separate UK annual conferences. Items and services which are regularly used and/or clinically significant were selected and, where possible, alternatives to those items were included for comparison. Participants were also asked for their grade and specialty. An estimate was deemed correct if it was within 20% of the actual cost. Planned subgroup analyses for grade and specialty were performed.

RESULTS

The 143 participants consisted of 23 (16%) consultants, 39 (27%) registrars, 33 (23%) SHOs and 48 (34%) foundation doctors. Of the 95 participants who were SHO grade or more senior, 67 (71%) work within general surgery. Across all items, only 9.6% of estimates were correct. There was no statistically significant difference between training levels (consultant 11.5%, registrar 10.1%, SHO 8.6%, foundation 8.9%; p = 0.253). Participants were significantly less successful in correctly estimating the cost of high value (>£150 [USD $198; EUR €175]) items (8.5% vs. 11.1%); p = 0.011, and the cost of devices as compared to the cost of services (7.4% vs. 15.0%); p = 0.001.

CONCLUSION

Surgeons across all grades and specialties have poor knowledge of device and service costs. It is important that this improves in order to allow surgeons to make a meaningful contribution to NHS efficiency savings by making informed decisions about their use of devices and services.

Sphingolipids and acid ceramidase as therapeutic targets in cancer therapy

BACKGROUND

Sphingolipids have been shown to play a key part in cancer cell growth and death and have increasingly become the subject of novel anti-cancer therapies. Acid ceramidase, a sphingolipid enzyme, has an important role in the regulation of apoptosis. In this review we aim to assess the current evidence supporting the role of sphingolipids in cancer and the potential role that acid ceramidase may play in cancer treatment.

METHODS

A literature search was performed for published full text articles using the PubMed, Cochrane and Scopus databases using the search criteria string "acid ceramidase", "sphingolipid", "cancer". Additional papers were detected by scanning the references of relevant papers. A summary of the evidence for each cancer subgroup was then formed. Given the nature of the data extracted, no meta-analysis was performed.

RESULTS

Over expression of acid ceramidase has been demonstrated in a number of human cancers. In vitro data demonstrate that manipulation of acid ceramidase may present a useful therapeutic target. In the clinical setting, a number of drugs have been investigated with the ability to target acid ceramidase, with the most promising of those being small molecular inhibitors, such as LCL521.

CONCLUSION

The role of the sphingolipid pathway in cancer is becoming very clearly established by promoting ceramide accumulation in response to cancer or cellular stress. Acid ceramidase is over expressed in a variety of cancers and has a role as a potential target for inhibition by novel specific inhibitors or off-target effects of traditional anti-cancer agents. Further work is required to develop acid ceramidase inhibitors safe for progression to clinical trials.

Development of an orthotopic syngeneic murine model of colorectal cancer for use in translational research

Improving outcomes in colorectal cancer requires more accurate in vivo modelling of the disease in humans, allowing more reliable pre-clinical assessment of potential therapies. Novel imaging techniques are necessary to improve the longitudinal assessment of disease burden in these models, reducing the number of animals required for translational studies. This report describes the development of an immune-competent syngeneic orthotopic murine model of colorectal cancer, utilising caecal implantation of CT26 cells stably transfected with the luciferase gene into immune-competent BALB/c mice, allowing serial bioluminescent imaging of cancer progression. Luminescence in the stably transfected CT26 cell line, after pre-conditioning in the flank of a BALB/c mouse, accurately reflected cell viability and resulted in primary caecal tumours in five of eight (63%) mice in the initial pilot study following caecal injection. Luminescent signal continued to increase throughout the study period with one mouse (20%) developing a liver metastasis. Histopathological assessment confirmed tumours to be consistent with a poorly differentiated adenocarcinoma. We have now performed this technique in 68 immune-competent BALB/c mice. There have been no complications from the procedure or peri-operative deaths, with primary tumours developing in 44 (65%) mice and liver metastases in nine (20%) of these. This technique provides an accurate model of colorectal cancer with tumours developing in the correct microenvironment and metastasising to the liver with a similar frequency to that seen in patients presenting with colorectal cancer, with serial bioluminescent reducing the murine numbers required in studies by removing the need for cull for assessment of disease burden.

Prospective cohort study of surgical trainee experience of access to gastrointestinal endoscopy training in the UK and Ireland

INTRODUCTION

Surgical trainees are reporting barriers to training in gastrointestinal (GI) endoscopy. This snapshot survey aimed to gather data on variation in access to quality GI endoscopy training for Colorectal and Upper Gastrointestinal (GI) surgical trainees across the UK and Ireland.

MATERIALS AND METHODS

An online 20-point survey was designed and distributed nationally to surgical trainee members of the Association of Surgeons in Training (ASiT), Dukes and The Roux Group (formerly Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland Trainees). The survey was designed in collaboration with The Roux Group for Upper GI trainees and the Dukes' Club for Colorectal trainees.

RESULTS

218 responses were received, most with a Colorectal or Upper GI sub-specialty interest (colorectal 56.0%; upper GI surgery 25.7%). Only 28.6% of trainees attended a dedicated training endoscopy list at least once a week with 28.1% not attending any at all. Less than half of trainees reported having endoscopy formally timetabled on rotas (36.9%). Most trainees (88.0%) encountered difficulties in gaining endoscopy training including lack of available lists (77.2%), conflicting operative commitments (59.4%), preferential allocation of lists to gastroenterology trainees (57.9%) and resistance from endoscopy departmental leads (38.6%). Regarding JAG accreditation, 77.1% respondents felt it should be mandatory prior to CCT with 80.3% believing this would lead to better access to dedicated endoscopy training equivalent to gastroenterology trainees. 93.1% trainees felt that attaining JAG accreditation by surgical trainees was important to patient care.

DISCUSSION

This study demonstrates significant barriers in accessing GI endoscopy training for general surgical trainees which urgently needs to be improved. In order to meet JAG training requirements for surgical trainees, a multifaceted collaborative approach from surgical and gastroenterology training bodies, local JAG trainers and the General Surgery SAC and JCST is required. This is to ensure that endoscopy is promoted and a robust model of training is successfully designed and delivered to general surgery trainees.

Correction: The Nrf2 inhibitor brusatol is a potent antitumour agent in an orthotopic mouse model of colorectal cancer

[This corrects the article DOI: 10.18632/oncotarget.25497.].

Multi-consultant operating

Can it help us push surgical boundaries?

The Nrf2 inhibitor brusatol is a potent antitumour agent in an orthotopic mouse model of colorectal cancer

Nrf2 is a transcription factor that regulates cellular stress response and irinotecan-metabolising pathways. Its aberrant activity has been reported in a number of cancers, although relatively few studies have explored a role for Nrf2 in colorectal cancer (CRC). This study assessed the expression of Nrf2 in patient CRC tissues and explored the effect of Nrf2 modulation alone, or in combination with irinotecan, in human (HCT116) and murine (CT26) cell lines in vitro and in an orthotopic syngeneic mouse model utilising bioluminescent imaging. Using a tissue microarray, Nrf2 was found to be overexpressed (p<0.01) in primary CRC and metastatic tissue relative to normal colon, with a positive correlation between Nrf2 expression in matched primary and metastatic samples. In vitro experiments in CRC cell lines revealed that Nrf2 siRNA and brusatol, which is known to inhibit Nrf2, decreased viability and sensitised cells to irinotecan toxicity. Furthermore, brusatol effectively abrogated CRC tumour growth in subcutaneously and orthotopically-allografted mice, resulting in an average 8-fold reduction in luminescence at the study end-point (p=0.02). Our results highlight Nrf2 as a promising drug target in the treatment of CRC.

Proteomic profiling of rectal cancer reveals acid ceramidase is implicated in radiation response

BACKGROUND

Neoadjuvant chemoradiotherapy (CRT) is used in locally advanced rectal cancer when tumours threaten the circumferential resection margin, with varying response to treatment. This experimental study aimed to identify significantly differentially expressed proteins between patients responding and not responding to CRT, and to validate any proteins of interest.

METHODS

Mass spectrometry (with isobaric tagging for relative quantification) analysis of rectal cancers pre- and post-CRT, and at resection. Validation of proteins of interest was performed by assessing tissue microarray (TMA) immunohistochemistry expression in a further 111 patients with rectal cancer.

RESULTS

Proteomic data are available via ProteomeXchange with identifier PXD008436. Reduced abundance of contributing peptide ions for acid ceramidase (AC) (log fold change -1.526, p = 1.17E-02) was observed in CRT responders. Differential expression of AC was confirmed upon analysis of the TMAs. Cancer site expression of AC in stromal cells from post-CRT resection specimens was observed to be relatively low in pathological complete response (p = 0.003), and relatively high with no response to CRT (p = 0.017).

CONCLUSION

AC may be implicated in the response of rectal cancer to CRT. We propose its further assessment as a novel potential biomarker and therapeutic target.

SIGNIFICANCE

There is a need for biomarkers to guide the use of chemoradiotherapy in rectal cancer, as none are in routine clinical use. We have determined acid ceramidase may have a role in radiation response, based on novel proteomic profiling and validation in a wider dataset using tissue microarrays. The ability to predict or improve response would positively select those patients who will derive benefit, prevent delays in the local and systemic management of disease in non-responders, and reduce morbidity associated with chemoradiotherapy.

Intravenous injection of unfunctionalized carbon-based nanomaterials confirms the minimal toxicity observed in aqueous and dietary exposures in juvenile rainbow trout (Oncorhynchus mykiss)

Numerous ecotoxicology studies of carbon-based nanomaterials (CNMs) have been conducted in fishes; however, different approaches have been used to make CNM dispersions and dose tanks for aqueous exposures, and to prepare food containing CNMs for dietary studies. This diversity of experimental methods has led to conflicting results and difficulties in comparing studies. The objective of the present study was to evaluate intravenous injection of unfunctionalized CNMs in rainbow trout (Oncorhynchus mykiss), as a means of delivering a known internal dose, on tissue biochemistry and histopathological lesions; then, subsequently, to compare the results with our previous work on aqueous and dietary exposures of rainbow trout to CNMs. Rainbow trout were injected in the caudal vein with corn oil dispersions of 200 μg (approximately 1 μg g^-1) of either the fullerene C₆₀, single-walled carbon nanotubes (SWCNTs), or amorphous carbon black. After 96 h, injected fish were euthanized and tissue samples collected for biochemistry and histology. Histological examination of the kidney of fish injected intravenously indicated the presence of black material consistent with the injected carbon treatments. However, there were no additional lesions associated with CNM exposure compared to controls. There were also no significant changes in haematology, or ionoregulatory disturbance in blood plasma among the intravenously injected fish. Significant elevation in lipid peroxidation (thiobarbituric acid reactive substances TBARS) was detected only in kidney and spleen of fish injected with SWCNTs, but not the other carbon treatments. The elevated TBARS following injection contrasted with CNMs delivered via aqueous or dietary routes in our previous studies, suggesting that the latter exposure routes may not lead to absorption and toxicity in the internal tissues. Comparison of the effects of injected CNMs with aqueous and dietary CNMs exposures indicates that these materials are of minimal environmentally-relevant toxicity in rainbow trout.

Exome sequencing of synchronously resected primary colorectal tumours and colorectal liver metastases to inform oncosurgical management

BACKGROUND

Next generation sequencing technology has facilitated mapping of the colorectal cancer genotype and furthered our understanding of metastogenesis. The aim of this study was to investigate for conserved and different mutations in the exomes of synchronously resected primary colorectal tumour and liver metastases. This information could potentially be utilised to guide the treatment of advanced disease with the help of biological information from the primary tumour.

METHODS

We performed exome sequencing of synchronously resected primary colorectal cancer and colorectal liver metastases as well as normal colonic mucosa and liver parenchyma, from four patients who had received neo-adjuvant chemotherapy, at a depth of 50X using the Ion Proton platform. Raw data was mapped to the reference genome prior to variant calling, annotation and downstream analysis.

RESULTS

Exome sequencing identified 585 non-synonymous missense single nucleotide variants (SNVs), of which 215 (36.8%) were unique to the primary tumour, 226 (38.6%) unique to the metastasis and 81 (13.8%) present in patient matched pairs. SNVs identified in the ErbB pathway appear to be concordant between primary and metastatic tumours.

CONCLUSION

Only 13.8% of the metastatic exome can be predicted by the genotype of the primary tumour. We have demonstrated concordance of a number of SNVs in the ErbB pathway, which may inform selection of therapeutic agents in advanced colorectal cancer.

Post-operative C-reactive protein profile following abdominal wall reconstruction with transversus abdominis posterior components separation

INTRODUCTION

Abdominal wall reconstruction using posterior component separation with transversus abdominis release (AWTAR) produces a unique post-operative CRP profile, when compared to routine elective colorectal operations. Therefore, we aim to establish the normal post-operative C-reactive protein (poCRP) profile following AWRTAR and reduce the unnecessary invasive interventions in patients already at greater risk of septic complications.

METHODS

A retrospective analysis of daily poCRP levels was performed both for patients who underwent uncomplicated AWRTAR (n=12), and a comparator group of uncomplicated open right hemicolectomies (RH) matched for age and sex (n=24). All operations in both groups were performed by a single surgeon from 2013 to 2015.

RESULTS

The median (IQR) age was 62 (16) and 67 (16) years respectively, with a higher proportion of males to females in both groups (10:2 vs. 17:7). The poCRP profile follows an initial steep rise, peaking at day 2 followed by a gradual washout phase. The poCRP peak is significantly greater in the AWRTAR group compared to the RH group (274 [95%CI ±25] vs. 160 [95%CI±27]; p=0.0001), with a positive correlation between day 2 CRP levels and operative length (r=0.56).

CONCLUSIONS

We have demonstrated that uncomplicated AWRTAR provokes a significantly greater poCRP rise (>200) compared to that well described in the literature for uncomplicated open colectomy. As poCRP is an important marker of post-operative recovery with abnormally high levels associated with septic complications, these data should help clinicians interpret the post-operative clinical course after AWRTAR.

Re-examining HSPC1 inhibitors

HSPC1 is a critical protein in cancer development and progression, including colorectal cancer (CRC). However, clinical trial data reporting the effectiveness of HSPC1 inhibitors on several cancer types has not been as successful as predicted. Furthermore, some N-terminal inhibitors appear to be much more successful than others despite similar underlying mechanisms. This study involved the application of three N-terminal HSPC1 inhibitors, 17-DMAG, NVP-AUY922 and NVP-HSP990 on CRC cells. The effects on client protein levels over time were examined. HSPC1 inhibitors were also applied in combination with chemotherapeutic agents commonly used in CRC treatment (5-fluorouracil, oxaliplatin and irinotecan). As HSPA1A and HSPB1 have anti-apoptotic activity, gene-silencing techniques were employed to investigate the significance of these proteins in HSPC1 inhibitor and chemotherapeutic agent resistance. When comparing the action of the three HSPC1 inhibitors, there are distinct differences in the time course of important client protein degradation events. The differences between HSPC1 inhibitors were also reflected in combination treatment-17-DMAG was more effective compared with NVP-AUY922 in potentiating the cytotoxic effects of 5-fluorouracil, oxaliplatin and irinotecan. This study concludes that there are distinct differences between N-terminal HSPC1 inhibitors, despite their common mode of action. Although treatment with each of the inhibitors results in significant induction of the anti-apoptotic proteins HSPA1A and HSPB1, sensitivity to HSPC1 inhibitors is not improved by gene silencing of HSPA1A or HSPB1. HSPC1 inhibitors potentiate the cytotoxic effects of chemotherapeutic agents in CRC, and this approach is readily available to enter clinical trials. From a translational point of view, there may be great variability in sensitivity to the inhibitors between individual patients.

Pregnant and severe acute abdominal pain: A surgical diagnostic dilemma

Acute abdominal pain in pregnancy remains a surgical conundrum. A 25-year-old primigravid at 29 weeks gestation presented with a two-week history of epigastric pain, nausea and vomiting. She had a distended abdomen consistent with a full term gravid uterus; tender at the epigastric and right hypochondrium suggestive of small bowel obstruction or acute appendicitis. Abdominal ultrasound was inconclusive but abdominal Computed Tomography (CT) suggested small bowel volvulus. An exploratory laparotomy revealed a segmental jejunal volvulus and small bowel diverticulum contributing to the volvulus. A short segmental bowel resection was performed. Histopathology confirmed a Meckel's Diverticulum. The patient recovered well but underwent premature labour 10 days later. Small bowel obstruction secondary to Meckel's diverticulum is rare in pregnancy. In an acute gestational abdomen, clinical examination is key. Radiological imaging may be helpful, whilst surgical intervention is confirmatory and therapeutic in the event of an obstructive volvulus.

Laparoendoscopic Transgastric Enucleation of an awkwardly sited Peri-Cardial Gastrointestinal Stromal Tumour (GIST): A Multi- Modal Approach

In the modern era of surgery, minimally invasive surgery is increasingly applied for excision of gastrointestinal stromal tumors. Site, size and tumor location are important factors that affect the surgical approach and excision. We performed a laparoendoscopic transgastric enucleation of a 4-cm pericardial endophytic gastrointestinal stromal tumor (GIST) using an energy device. The surgery was successful and post-operative recovery uneventful. No tumor recurrence was detected on surveillance gastroscopy. In the safe hands of a well-trained laparoscopic upper gastrointestinal surgeon, pericardial GIST can be enucleated safely by this method. The avoidance of surgical staplers is not only cost-effective, but also reduces the risk of associated complications.

Effect of Exercise on Pulmonary Function Tests in Obese Malaysian Patients

BACKGROUND AND AIMS

Obesity has taken the 21st century by storm, posing negative effects on of the various facades of health, healthcare and global economy. With regards to pulmonary performance, numerous studies have proven the detrimental effects of obesity while reinstating the positive effects of weight loss on overall pulmonary function. However, effects of exercise on pulmonary function and correlation between changes in pulmonary function test with weight loss have yet to be described. We performed a prospective interventional study to determine the effects of regular exercise on Pulmonary Function Tests (PFT) and ascertain the relationship between weight loss and change in PFT in obese patients.

MATERIALS AND METHODS

Twenty-five obese patients were enrolled, giving an 80% power of study. Baseline weight and PFT consisting of FEV1, FVC, TLC, mean ERV and VC were recorded prior to commencement of the 8 week long Standard Exercise Regimen (SER). PFT and weight were recorded again at the end of 8 weeks.

RESULTS

All parameters of the PFT studied improved significantly with exercise. The participants lost an average of 1kg of body weight post-exercise (p<0.0005). The correlations between mean changes in weight and PFT were negligible.

CONCLUSIONS

A period of supervised regular exercise improves the pulmonary function of obese patients and this improvement is independent of the amount of weight loss. Hence, SER should be recommended to all obese patients, especially when bariatric surgery is desired.

Predicting response to treatment for colorectal cancer: a review of relevant mechanisms and potential biomarkers

Abstract 

Neoadjuvant therapy for colorectal cancer offers potential oncological benefits but is associated with increased surgical risk. Predictive biomarkers would allow the personalization of this risk/benefit balance, with treatment stratified by likely response. Although current clinical application of predictive biomarkers is limited, a number of potential targets have been proposed. This review summarizes some of the approaches being used to develop predictive biomarkers for the personalization of colorectal cancer management.

Evaluation of a novel tissue stabilization gel to facilitate clinical sampling for translational research in surgical trials

Background

The aim was to establish the feasibility of using a tissue stabilization gel (Allprotect™) as an alternative to liquid nitrogen to facilitate collection of clinical samples for translational research.

Methods

Tumour samples from patients undergoing surgery for primary or metastatic colorectal cancer were either snap-frozen in liquid nitrogen or stored in Allprotect™ under a number of different conditions. Sample integrity was compared across different storage conditions by assessing biomolecule stability and function. DNA quality was assessed spectrophotometrically and by KRas genotyping by pyrosequencing. Total RNA retrieval was determined by nanodrop indices/RNA integrity numbers, and quality assessed by reverse transcription–PCR for two representative genes (high-mobility group box 1, HMGB1; carboxylesterase 1, CES1) and two microRNAs (miR122 and let7d). Western blot analysis of HMGB1 and CES1 was used to confirm protein expression, and the metabolic conversion of irinotecan to its active metabolite, SN-38, was used to assess function.

Results

Under short-term storage conditions (up to 1 week) there was no apparent difference in quality between samples stored in Allprotect™ and those snap-frozen in liquid nitrogen. Some RNA degradation became apparent in tissue archived in Allprotect™ after 1 week, and protein degradation after 2 weeks.

Conclusion

In hospitals that do not have access to liquid nitrogen and –80°C freezers, Allprotect™ provides a suitable alternative for the acquisition and stabilization of clinical samples. Storage proved satisfactory for up to 1 week, allowing transfer of samples without the need for specialized facilities. Surgical relevanceAccess to clinical material is a fundamental component of translational research that requires significant infrastructure (research personnel, liquid nitrogen, specialized storage facilities). The aim was to evaluate a new-to-market tissue stabilization gel (Allprotect™), which offers a simple solution to tissue preservation without the need for complex infrastructure.Allprotect™ offers comparable DNA, RNA and protein stabilization to tissue snap-frozen in liquid nitrogen for up to 1 week. Degradation of biomolecules beyond this highlights its role as a short-term tissue preservative.Allprotect™ has the potential to increase surgeon participation in translational research and surgical trials requiring tissue collection.

Arterial embolization of a bleeding gastric Dieulafoy lesion: a case report

Dieulafoy's lesion is one of an unusual cause of upper gastrointestinal bleeding (U GIB). Endoscopic intervention has always been a preferred non-surgical method in treating UGIB including bleeding from Dieulafoy's lesion. Owing to recent advances in angiography, arterial embolization has become a popular alternative in non- variceal UGIB especially in cases with failed endoscopic treatment. However, managing bleeding Dieulafoy's with selective arterial embolization as the first line of treatment has not been exclusively practiced. We hereby, report a case of bleeding Dieulafoy lesion which had been primarily treated with arterial embolization.

Refeeding syndrome: the danger of feeding a starving man

Refeeding syndrome is a potentially fatal clinical condition characterized by severe electrolyte and fluid shifts associated with metabolic abnormalities in severely malnourished or starved patients undergoing oral, enteral or parenteral refeeding. We here present a case of a 50-year-old Indian male with a background of depression and alcoholic liver disease presented with alleged ingestion of a detergent. He subsequently developed an oesophageal stricture resulting in severe malnutrition. He developed refeeding syndrome following commencement of TPN associated with clear biochemical alteration. This was immediately identified and rectified. This case report highlights the prevalence of refeeding syndrome in a typical hospital setting that can easily be overlooked and stresses the importance of early recognition as this is a preventable disorder.

Attitudes, motivators, and barriers to a career in surgery: a national study of U.K. undergraduate medical students

INTRODUCTION

Numerous factors influence the career choices of undergraduate medical students, although little work has focused specifically on the surgical specialties. We aimed to investigate medical students' early experiences of surgery along with the motivators and barriers to selecting a surgical career.

METHODS

All final-year medical students were invited to participate in an online survey. A range of quantitative data (expressed as a proportion of total respondents) and qualitative data (grouped and thematically analyzed) were collected to evaluate students' attitudes to careers in surgery and potential influences on these.

RESULTS

A total of 482 students from 20 medical schools throughout England and Wales completed the survey. Overall, 91% of respondents had work experience before medical school, in which the greatest satisfaction was reported in the 21% who undertook placements in surgery. In addition, 58% expressed a desire to spend time working abroad and 59% to undertake a period of research; the primary motivator for both was career/professional development. Surgery was the most popular career choice amongst respondents. The 2 most important factors in decisions pertaining to their career were reported as interest in the specialty and work-life balance. Students draw career advice from numerous sources, most commonly mentors (49%) and student surgical societies (46%). Only 1% wanted more website information, with personal contact being paramount.

DISCUSSION

It is vital for the continuing strength of the profession and the quality of surgery for the public that we continue to attract the best undergraduates into careers in surgery. Surgeons of all grades must be aware that how they are perceived by students affects future career choices. Early experiences of surgery are fundamental in assisting medical students to make informed career choices.

Single incision laparoscopic surgery (SILS) inguinal hernia repair - recent clinical experiences of this novel technique

Inguinal hernia remains the most commonly encountered surgical problem. Various methods of repair have been described, and the most suitable one debated. Single port access (SPA) surgery is a rapidly evolving field, and has the advantage of affording 'scarless' surgery. Single incision laparoscopic surgery (SILS) for inguinal hernia repair is seen to be feasible in both total extraperitoneal (TEP) and transabdominal pre-peritoneal (TAPP) approaches. Data and peri-operative information on both of these however are limited. We aimed to review the clinical experience, feasibility and short term complications related to laparoscopic inguinal hernia repair via single port access. A literature search was performed using Google Scholar, Springerlink Library, Highwire Press, Surgical Endoscopy Journal, World Journal of Surgery and Medscape. The following search terms were used: laparoscopic hernia repair, TAPP, TEP, single incision laparoscopic surgery (SILS). Fourteen articles in English language related to SILS inguinal hernia repair were identified. Nine articles were related to TEP repair and the remaining 5 to TAPP. A total of 340 patients were reported within these studies: 294 patients having a TEP repair and 46 a TAPP. Only two cases of recurrence were reported. Various ports have been utilized, including the SILS port, Tri-Port and a custom- made port using conventional laparoscopic instruments. The duration of surgery was 40-100 minutes and the average length of hospital stay was one day. Early outcomes of this novel technique show it to be feasible, safe and with potentially better cosmetic outcome.