Risk of metachronous colorectal cancer following colectomy in Lynch syndrome: a systematic review and meta-analysis

AIM

Lynch syndrome (LS) accounts for 2-4% of all colorectal cancer (CRC) cases, and is associated with an increased risk of developing metachronous colorectal cancer (mCRC). The role of extended colectomy in LS CRC is controversial. There are limited studies comparing the risk of mCRC following segmental colectomy and extended colectomy. The objective of this systematic review is to evaluate the risk of developing mCRC following segmental and extended colectomy for LS CRC and endoscopic compliance.

METHOD

A systematic review of major databases was performed using predefined terms. All original articles published in English comparing the risk of mCRC in LS patients after segmental and extended colectomy from 1950 to January 2016 were included.

RESULTS

The search retrieved 324 studies. Six studies involving 871 patients met the inclusion criteria. Of these, 705 (80.9%) underwent segmental colectomy and 166 (19.1%) extended colectomy. Average follow-up was 91.2 months. The mCRC rate was 22.8% and 6% in the segmental and extended colectomy groups, respectively. The segmental group were over four times more likely to develop mCRC (OR 4.02, 95% CI: 2.01-8.04, P < 0.0001). mCRC occurred in patients after segmental colectomy despite 1-2-yearly postoperative endoscopic surveillance.

CONCLUSION

This result suggests that extended colectomy reduces the risk of mCRC by over four-fold compared with segmental colectomy. mCRC occurred in the segmental group despite postoperative endoscopic surveillance. This needs to be borne in mind when deciding on the appropriate surgical management of LS patients with CRC. We recommend that extended colectomy should be considered for patients with confirmed LS CRC.

Neutrophil-lymphocyte ratio, pain perception, and disease activity score may serve as important predictive markers for sustained remission in rheumatoid arthritis

The implementation of new treatment strategies based on current recommendations has enabled a greater number of patients with rheumatoid arthritis (RA) to achieve remission. However, there are no definite predictors of sustained remission. Moreover, the absence of clear consensus on the time of withdrawal or reduction of treatment further adds to the treatment burden. This pilot study was intended to evaluate the prognostic potential of various RA-related parameters. All the enrolled subjects (n=124) were clinically evaluated on the basis of various parameters including age, gender, duration of illness before the initiation of disease-modifying anti-rheumatic drugs, tender and swollen joints (28 joints), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), hemoglobin percentage, lymphocyte count, total white-blood cell counts, and neutrophil to lymphocyte ratio (NLR). Student's t-test and discriminant function analysis were performed. The specificity of all parameters and their best possible cut-off to predict relapse were calculated using the receiver operating characteristic (ROC) analysis. A significant difference in terms of pain perception, NLR, tendency to have a significant tender joint count and absolute lymphocyte counts was identified between the patients in sustained remission and those in relapse. The ROC analysis indicated that NLR was consistent in predicting remission. CRP, ESR, and/or disease activity score may not be very effective in differentiating patients with sustainable remission/low disease activity. NLR along with patient's perception of pain may assist in predicting sustained remission.

Effects of ex vivo blood anticoagulation and preanalytical processing time on the proteome content of platelets

BACKGROUND

Ex vivo assays of platelet function critically inform mechanistic and clinical hematology studies, where effects of divergent blood processing methods on platelet composition are apparent, but unspecified.

OBJECTIVE

Here, we evaluate how different blood anticoagulation options and processing times affect platelet function and protein content ex vivo.

METHODS

Parallel blood samples were collected from healthy human donors into sodium citrate, acid citrate dextrose, EDTA or heparin, and processed over an extended time course for functional and biochemical experiments, including platelet proteome quantification with multiplexed tandem mass tag (TMT) labeling and triple quadrupole mass spectrometry (MS).

RESULTS

Each anticoagulant had time-dependent effects on platelet function in whole blood. For instance, heparin enhanced platelet agonist reactivity, platelet-monocyte aggregate formation and platelet extracellular vesicle release, while EDTA increased platelet α-granule secretion. Following platelet isolation, TMT-MS quantified 3357 proteins amongst all prepared platelet samples. Altogether, >400 proteins were differentially abundant in platelets isolated from blood processed at 24 h versus 1 h post-phlebotomy, including proteins pertinent to membrane trafficking and exocytosis. Anticoagulant-specific effects on platelet proteomes included increased complement system and decreased α-granule proteins in platelets from EDTA-anticoagulated blood. Platelets prepared from heparinized blood had higher levels of histone and neutrophil-associated proteins in a manner related to neutrophil extracellular trap (NET) formation and platelet:NET interactions in whole blood ex vivo.

CONCLUSION

Our results demonstrate that different anticoagulants routinely used for blood collection have varying effects on platelets ex vivo, where methodology-associated alterations in platelet proteome may influence mechanistic, translational and biomarker studies.

Systematic literature review of learning curves for colorectal polyp resection techniques in lower gastrointestinal endoscopy

AIM

The performance of therapeutic procedures in lower gastrointestinal endoscopy (LGI) can be challenging and carries an increased risk of adverse events. There is increasing demand for the training of endoscopists in these procedures, but limited guidelines exist concerning procedural competency. The aim of this study was to assess the learning curves for LGI polypectomy, colorectal endoscopic mucosal resection (EMR) and colorectal endoscopic submucosal dissection (ESD).

METHOD

A systematic review of electronic databases between 1946 and September 2019 was performed. Citations were included if they reported learning curve data. Outcome measures that defined the success of procedural competency were also recorded.

RESULTS

A total of 34 out of 598 studies met the inclusion criteria of which 28 were related to ESD, three to polypectomy and three to EMR. Outcome measures for polypectomy competency (en bloc resection, delayed bleeding and independent polypectomy rate) were achieved after completion of between 250 and 400 polypectomies and after 300 colonoscopies. EMR outcome measures, including complete resection and recurrence, were achieved variably between 50 and 300 procedures. Outcome measures for ESD included efficiency (resection rates and procedural speed) and safety (adverse events). En bloc resection rates of over 80% and R0 resection rates of over 70% were achieved at 20-40 cases and procedural speed increased after 30 ESD cases. Competency in safety metrics was variably achieved at 20-200 cases.

CONCLUSION

There is a paucity of data on learning curves in LGI polypectomy, EMR and ESD. Despite limited evidence, we have identified relevant outcome measures and threshold numbers for the most common LGI polyp resection techniques for potential inclusion in training programmes/credentialing guidelines.

Ulcerative colitis in sickle cell disease

Four patients with homozygous sickle cell disease and severe proctocolitis are described. The current prevalence is three patients per 1,000 attending a sickle cell clinic. The reasons for the apparent predisposition of sickle cell disease to proctocolitis could not be determined but was revealed by the large follow-up clinic.

An international survey of polypectomy training and assessment

Background and study aims Colonic polypectomy is acknowledged to be a technically challenging part of colonoscopy. Training in polypectomy is recognized to be often inconsistent. This study aimed to ascertain worldwide practice in polypectomy training. Patients and methods An electronic survey was distributed to endoscopic trainees and trainers in 19 countries asking about their experiences of receiving and delivering training. Participants were also asked about whether formal polypectomy training guidance existed in their country. Results Data were obtained from 610 colonoscopists. Of these responses, 348 (57.0 %) were from trainers and 262 (43.0 %) from trainees; 6.6 % of trainers assessed competency once per year or less often. Just over half (53.1 %) of trainees had ever had their polypectomy technique formally assessed by any trainer. Approximately half the trainees surveyed (51.1 %) stated that the principles of polypectomy had only ever been taught to them intermittently. Of those trainees with the most colonoscopy experience, who had performed over 500 procedures, 48.2 % had had training on removing large polyps of over 10 mm; 46.2 % (121 respondents) of trainees surveyed held no record of the polypectomies they had performed. Only four of the 19 countries surveyed had specific guidelines on polypectomy training. Conclusions A significant number of competent colonoscopists have never been taught how to perform polypectomy. Training guidelines worldwide generally give little direction as to how trainees should acquire polypectomy skills. The learning curve for polypectomy needs to be defined to provide reliable guidance on how to train colonoscopists in this skill.

Delusional parasitosis: Worms of the mind

Delusional parasitosis is an uncommon psychotic illness. Patients often report to dermatologists and physicians for treatment and are brought to psychiatric attention only for associated psychological distress. One such case is discussed in this report.

The Karyology of Uraeotyphlus gansi, and Its Implications for the Systematics and Evolution of Uraeotyphlidae (Amphibia: Gymnophiona)

The gross karyotype of the uraeotyphlid caecilian Uraeotyphlus gansi is described as comprising 2n = 42 and fundamental number = 58. These are the first karyotype data for any species of malabaricus-group Uraeotyphlus, and the diploid number is the same as those ichthyophiids thus far studied and differs from the oxyurus-group Uraeotyphlus (2n = 36). These data support the recognition of two species groups within Uraeotyphlus, the monophyly of the oxyurus group, and the understanding that the ancestral diatriatan was more ichthyophiid- than uraeotyphlid-like.

Subcellular/tissue distribution and responses to oil exposure of the cytochrome P450-dependent monooxygenase system and glutathione S-transferase in freshwater prawns (Macrobrachium malcolmsonii, M. lamarrei lamarrei)

Subcellular fractions (mitochondrial, cytosolic and microsomal) prepared from the tissues (hepatopancreas, muscle and gill) of freshwater prawns Macrobrachium malcolmsonii and Macrobrachium lamarrei lamarrei were scrutinized to investigate the presence of mixed function oxygenase (MFO) and conjugating enzymes (glutathione-S-transferase, GST). Cytochrome P450 (CYP) and other components (cytochrome b(5); NADPH-cytochrome c (CYP) reductase and NADH-cytochrome c-reductase activities) of the MFO system were predominantly present in the hepatic microsomal fraction of M. malcolmsonii and M. lamarrei lamarrei. The results are in agreement with the notion that monooxygenase system is mainly membrane bound in the endoplasmic reticulum, and that the hepatopancreas is the major metabolic tissue for production of biotransformation enzymes in crustaceans. Further, the prawns were exposed to two sublethal (0.9 ppt (parts per thousand) and 2.3 ppt) concentrations of oil effluent. At the end of 30th day, hydrocarbons and detoxifying enzymes were analysed in the hepatopancreas. The accumulations of hydrocarbon in the tissues gradually increased when exposed to sublethal concentrations of oil effluent and were associated with significantly enhanced levels of cytochrome P450 (180.6+/-6.34 pmol mg(-1) protein (P<0.05 versus control, 136.5+/-7.1 pmol mg(-1) protein) for 2.3 ppt and 305.6+/-8.5 pmol mg(-1) protein (P<0.001 versus control, 132.3+/-6.8 pmol mg(-1) protein] for 0.9 ppt of oil exposed M. malcolmsonii; 150+/-6.5 pmol mg(-1 )protein (P<0.01 versus control, 84.6+/-5.2 pmol mg(-1) protein) for 2.3 ppt and 175+/-5.5 pmol mg(-1) protein (P<0.01 versus control, 87.6+/-5.4 pmol mg(-1) protein) for 0.9 ppt of oil exposed M. lamarrei lamarrei), NADPH cytochrome c-reductase activity (14.7+/-0.6 nmol min(-1 )mg(-1) protein (P<0.05 versus control, 6.8+/-0.55 nmol min(-1 )mg(-1) protein) for 2.3 ppt and 12.1+/-0.45 nmol min(-1 )mg(-1) protein (P<0.01 versus control, 6.9+/-0.42 nmol min(-1 )mg(-1) protein) for 0.9 ppt of oil exposed M. malcolmsonii; 12.5+/-0.31 nmol min(-1 )mg(-1) protein (P<0.001 versus control, 4.6+/-0.45 nmol min(-1 )mg(-1) protein) for 2.3 ppt and 9.6+/-0.32 nmol min(-1 )mg(-1) protein (P<0.01 versus control, 4.9+/-0.41 nmol min(-1 )mg(-1) protein) for 0.9 ppt of oil exposed M. lamarrei lamarrei) and cytochrome b(5 )(124.8+/-3.73 pmol mg(-1) protein (P<0.01 versus control, 76.8+/-4.2 pmol mg(-1) protein) for 2.3 ppt and 115.3+/-3.86 pmol mg(-1) protein (P<0.01 versus control, 76.4+/-4.25 pmol mg(-1 )protein) for 0.9 ppt of oil exposed M. malcolmsonii and 110+/-3.11 pmol mg(-1) protein (P<0.01 versus control, 63.7+/-3.24 pmol mg(-1 )protein) for 2.3 ppt and 95.3+/-2.63 pmol mg(-1) protein (P<0.01 versus control, 61.4+/-2.82 pmol mg(-1) protein) for 0.9 ppt of oil exposed M. lamarrei lamarrei). The enhanced levels of biotransformation enzymes in oil-exposed prawns demonstrate a well-established detoxifying mechanism in crustaceans, and the response offers the possibility of use as a biomarker for the early detection of oil pollution.

Coronary artery disease and mesenteric artery stenosis - Two sides of the same coin? - Long term prospective analysis

Coronary artery disease (CAD) patients might have concomitant mesenteric artery stenosis (MAS). Identification of risk factors predicting mesenteric artery involvement might guide screening high risk individuals. A dilemma of intervention in radiologically severe MAS exists. This prospective study included CAD patients undergoing a coronary angiogram. A concomitant mesenteric angiogram was performed to diagnose MAS. Clinically relevant MAS (CR-MAS) was defined as i) presence of classical mesenteric angina with any degree of MAS or ii) severe stenosis (> 70%) involving two or more vessels. Risk factors for CR-MAS were studied and followed up prospectively. One hundred and three patients were included in the study. Left anterior descending artery was the most common involved coronary artery and was affected in 73% (n = 76). Mesenteric angiogram revealed 42.7% (n = 44) to have MAS. CR-MAS was present in 21 patients (20.4%). Involvement of celiac axis, superior mesenteric artery and inferior mesenteric artery was 22, 39 and 15 respectively. Multivariate analysis showed mesenteric angina (p < 0.01), diabetes mellitus (p < 0.01) and peripheral artery disease (p < 0.01) to be independent predictors of CR-MAS. At a median follow-up of 36 months (range 29-48 months), there was no acute mesenteric ischemia. In patients with CR-MAS, 16 (76.2%) had symptomatic improvement and 5 (23.8%) had stable symptoms. Three patients underwent angioplasty of superior mesenteric artery for persistent symptoms. Chronic CAD patients had a high prevalence of MAS. Mesenteric angina, diabetes mellitus and peripheral artery disease are independent predictors of CR-MAS. Intervention for MAS should be dictated by symptoms and not radiological severity. Lifestyle modification and medication for atherosclerotic ischemic heart disease probably prevents acute mesenteric ischemia in CAD patients.

Comparison of the time taken for subarachnoid block using ultrasound-guided method versus landmark technique for cesarean section - A randomized controlled study

Background and Aims:

Spinal anesthesia is the regional technique preferred for cesarean section and is usually administered using the traditional landmark technique. Ultrasonography of the spine appears to be helpful in locating the puncture site and increasing the success rate. The primary objective of this study was to assess the use of ultrasonogram in locating the lumbar interspinous space for spinal anesthesia in laboring parturients brought for elective cesarean section.

Material and Methods:

Sixty parturients scheduled to undergo elective cesarean section under spinal anesthesia were included in this prospective randomized controlled trial, after obtaining the institutional ethical clearance. In Group I, 30 patients received spinal anesthesia by landmark technique and in Group II, 30 patients underwent ultrasound-guided spinal anesthesia. The statistical analysis was done using SPSS software version 17 (SPSS Inc., Chicago, Illinois, USA) for Microsoft windows.

Results:

The time taken for spinal in Group I was longer than in Group II (62 ± 18s; 41 ± 11s; P = 0.0001). The number of attempts of needle insertion was significantly less in Group II (group I 1.86 ± 1.04: group II 1.06 ± 0.25). However, the total preparation time (28 8.30 ± 92 vs 804.73 ± 77; P = 0.0001) was more in the ultrasound-guided than in the landmark group. The patients had better satisfaction in group II.

Conclusion:

Preprocedural ultrasound is a useful tool for successful lumbar puncture in parturients as it minimizes the number of attempts of needle insertion and provides better patient satisfaction.