Obesity surgery and risk of cancer Mackenzie, H.; Markar, S. R.; Askari, A. ...
British journal of surgery,
November 2018, Letnik:
105, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Background
Obesity increases the risk of several types of cancer. Whether bariatric surgery influences the risk of obesity‐related cancer is not clear. This study aimed to uncover the risk of ...hormone‐related (breast, endometrial and prostate), colorectal and oesophageal cancers following obesity surgery.
Methods
This national population‐based cohort study used data from the Hospital Episode Statistics database in England collected between 1997 and 2012. Propensity matching on sex, age, co‐morbidity and duration of follow‐up was used to compare cancer risk among obese individuals undergoing bariatric surgery (gastric bypass, gastric banding or sleeve gastrectomy) and obese individuals not undergoing such surgery. Conditional logistic regression provided odds ratios (ORs) with 95 per cent confidence intervals.
Results
In the study period, from a cohort of 716 960 patients diagnosed with obesity, 8794 patients who underwent bariatric surgery were matched exactly with 8794 obese patients who did not have surgery. Compared with the no‐surgery group, patients who had bariatric surgery exhibited a decreased risk of hormone‐related cancers (OR 0·23, 95 per cent c.i. 0·18 to 0·30). This decrease was consistent for breast (OR 0·25, 0·19 to 0·33), endometrium (OR 0·21, 0·13 to 0·35) and prostate (OR 0·37, 0·17 to 0·76) cancer. Gastric bypass resulted in the largest risk reduction for hormone‐related cancers (OR 0·16, 0·11 to 0·24). Gastric bypass, but not gastric banding or sleeve gastrectomy, was associated with an increased risk of colorectal cancer (OR 2·63, 1·17 to 5·95). Longer follow‐up after bariatric surgery strengthened these diverging associations.
Conclusion
Bariatric surgery is associated with decreased risk of hormone‐related cancers, whereas gastric bypass might increase the risk of colorectal cancer.
Obesity affects cancer risk
Bariatric surgery is currently the most efficacious treatment for obesity and its associated metabolic co-morbidities, such as diabetes. The metabolic improvements occur through both weight-dependent ...and weight-independent mechanisms. Bile acids (BAs) have emerged as key signalling molecules that have a central role in modulating many of the physiological effects seen after bariatric surgery. This systematic review assesses the evidence from both human and animal studies for the role of BAs in reducing the metabolic complications of obesity following bariatric surgery.
We conducted a systematic search of Medline and Embase databases to identify all articles investigating the role of BAs in mediating the metabolic changes observed following bariatric surgery in both animal and human studies. Boolean logic was used with relevant search terms, including the following MeSH terms: 'bile acids and salts', 'bariatric surgery', 'metabolic surgery', 'gastrointestinal tract/surgery' and 'obesity/surgery'.
Following database searches (n=1197), inclusion from bibliography searches (n=2) and de-duplication (n=197), 1002 search results were returned. Of these, 132 articles were selected for full-text review, of which 38 articles were deemed relevant and included in the review. The findings support the effects of BAs on satiety, lipid and cholesterol metabolism, incretins and glucose homoeostasis, energy metabolism, gut microbiota and endoplasmic reticulum stress following bariatric surgery. Many of these metabolic effects are modulated through the BA receptors FXR and TGR5. We also explore a possible link between BAs and carcinogenesis following bariatric surgery.
Overall there is good evidence to support the role of BAs in the metabolic effects of bariatric surgery through the above mechanisms. BAs could serve as a novel therapeutic pharmacological target for the treatment of obesity and its associated co-morbidities.
Summary
This study reviews the predictive value of maximum oxygen consumption () and anaerobic threshold, obtained through cardiopulmonary exercise testing, in calculating peri‐operative morbidity ...and mortality in non‐cardiopulmonary thoraco‐abdominal surgery. A literature review provided nine studies that investigated either one or both of these two variables across a wide range of surgical procedures. Six of the seven studies that reported sufficiently detailed results on peak oxygen consumption and four of the six studies that reported sufficiently detailed results on anaerobic threshold found them to be significant predictors. We conclude that peak oxygen consumption and possibly anaerobic threshold are valid predictors of peri‐operative morbidity and mortality in non‐cardiopulmonary thoraco‐abdominal surgery. These indicators could potentially provide a means of allocating increased care to high‐risk patients.
Background
Obstructive sleep apnea (OSA) is an increasingly common disorder associated with increased cardiovascular disease, mortality, reduced productivity, and an increased risk of road traffic ...accidents. A significant proportion of patients with OSA in the UK are undiagnosed. This study aims to identify risk factors for OSA in an obese cohort.
Method
A population-based study was conducted of obese patients (BMI ≥ 30 kg/m
2
) from the Clinical Practice Research Datalink (CPRD). A logistic regression model was used to calculate odds ratios (ORs) for developing OSA according to other clinicopathological characteristics. Multivariate analysis was conducted of individual factors that affect the propensity to develop OSA. Statistical significance was defined as
p
< 0.050.
Results
From 276,600 obese patients identified during a data extraction of the CPRD in July 2017, the prevalence of OSA was 5.4%. The following risk factors were found to be independently associated with increased likelihood of OSA: male sex (OR = 3.273;
p
< 0.001), BMI class II (OR = 1.640;
p
< 0.001), BMI class III (OR = 3.768;
p
< 0.001), smoking (OR = 1.179;
p
< 0.001), COPD (OR = 1.722;
p
< 0.001), GERD (OR = 1.557;
p
< 0.001), hypothyroidism (OR = 1.311;
p
< 0.001), acromegaly (OR = 3.543;
p
< 0.001), and benzodiazepine use (OR = 1.492;
p
< 0.001). Bariatric surgery was associated with reduced risk of OSA amongst this obese population (OR = 0.260;
p
< 0.001).
Conclusions
In obese patients, there are numerous comorbidities that are associated with increased likelihood of OSA. These factors can help prompt clinicians to identify undiagnosed OSA. Bariatric surgery appears to be protective against developing OSA.
Background
Eye tracking presents a novel tool that could be used to profile skill levels in surgery objectively. The primary aim of this study was to identify differences in gaze behaviour between ...expert and junior surgeons performing a laparoscopic Roux‐en‐Y gastric bypass (LRYGB) for obesity.
Methods
This prospective observational study used a lightweight eye‐tracking apparatus to determine the difference in gaze behaviours between expert (more than 75 procedures) and junior (75 or fewer procedures) surgeons at defined stages of LRYGB. Primary endpoints were normalized dwell time and fixation frequency. Secondary endpoints were blink rate, maximum pupil size and rate of pupil change.
Results
A total of 20 procedures (12 junior, 8 expert) were analysed. Compared with juniors, experts showed a prolonged dwell time on the screen during angle of His dissection (median (range) 91·20 (83·40–94·40) versus 68·95 (59·80–87·60) per cent; P = 0·001), formation of the retrogastric tunnel (91·50 (85·80–95·50) versus 73·60 (34·60–90·50) per cent; P = 0·001) and gastric pouch formation (86·95 (83·60–90·20) versus 67·60 (37·10–80·00) per cent P < 0·001). Juniors had a greater blink frequency throughout all recorded segments (P < 0·010) and had a larger maximum pupil size during all recorded operative segments (P < 0·010). Rate of pupil change was greater in juniors in all analysed segments (P < 0·010).
Conclusion
These results suggest that experts display more focused attention on significant stimuli, alongside experiencing a reduced mental workload and having increased concentration. This has the potential for future use in validation of surgical skill in high‐stakes assessment.
Potential uses in training and assessment
The role of adjuvant chemotherapy after resection of colorectal cancers (CRCs) is well understood for patients with stage-I or stage-III disease. Its efficacy for those with stage-II disease remains ...much less clear. Many investigators have sought to identify prognostic markers that might clarify which patients have the highest risk of recurrence and would, therefore, be most likely to benefit from chemotherapy. This systematic review examines evidence for the use of peripherally sampled, circulating tumour cells (CTCs) as such a prognostic marker.
A comprehensive literature search was used to identify studies reporting on the significance of CTCs in the postoperative blood of CRC patients.
Fourteen studies satisfied the inclusion criteria. Six of the nine studies that took blood samples 24 h or more postoperatively found detection of postoperative CTCs to be an independent predictor of cancer recurrence.
The presence of CTCs in peripheral blood at least 24 h after resection of CRCs is an independent prognostic marker of recurrence. Further studies are needed to clarify the optimal time point for blood sampling and determine the benefit of chemotherapy in CTC-positive patients with stage-II disease.
Abstract
Green Pea galaxies are low-redshift starburst dwarf galaxies, with properties similar to those of the high-redshift galaxies that reionized the universe. We report the first mapping of the ...spatial distribution of atomic hydrogen (H
i
) in and around a Green Pea, GP J0213+0056 at
z
= 0.0399, using the Giant Metrewave Radio Telescope (GMRT). Like many Green Peas, GP J0213+0056 shows strong H
i
21 cm emission in single-dish spectroscopy, strong Ly
α
emission, and a high O
iii
λ
5007 Å/O
ii
λ
3727 Å luminosity ratio, O32 ≈ 8.8, consistent with a high leakage of Lyman-continuum radiation. Our GMRT H
i
21 cm images show that the H
i
21 cm emission in the field of GP J0213+0056 arises from an extended broken-ring structure around the Green Pea, with the strongest emission coming from a region between GP J0213+0056 and a companion galaxy lying ≈4.7 kpc away, and little H
i
21 cm emission coming from the Green Pea itself. We find that the merger between GP J0213+0056 and its companion is likely to have triggered the starburst, and led to a disturbed H
i
spatial and velocity distribution, which in turn allowed Ly
α
(and, possibly, Lyman-continuum) emission to escape the Green Pea. Our results suggest that such mergers, and the resulting holes in the H
i
distribution, are a natural way to explain the tension between the requirements of cold gas to fuel the starburst and the observed leakage of Ly
α
and Lyman-continuum emission in Green Pea galaxies and their high-redshift counterparts.
Aim To determine the accuracy of computed tomography (CT) in detecting disease with invasion beyond the muscularis propria (MP) and malignant lymph nodes. Materials and methods A literature search of ...Ovid, Embase, the Cochrane database, and Medline using Pubmed, Google™ Scholar and Vivisimo™ search engines was performed to identify studies reporting on the accuracy of CT to predict the staging of colonic tumours. Publication bias was demonstrated by Funnel plots. The sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated using a bivariate random effects model and hierarchical summary operating curves (HSROC) were generated. Results Nineteen studies fulfilled all the necessary inclusion criteria. The pooled sensitivity, specificity, DOR for detection of tumour invasion were 86% (95% CI: 78–92%); 78% (95% CI: 71–84%); 22.4 (95% CI: 11.9–42.4). Similarly, the values for nodal detection were 70% (95% CI: 63–73%); 78% (95% CI: 73–82%); 8.1(95% CI: 4.7–14.1). In the subgroup analysis, the best results were obtained in studies utilizing multidetector CT (MDCT). Conclusion Preoperative staging CT accurately distinguishes between tumours confined to the bowel wall and those invading beyond the MP; however, it is significantly poorer at identifying nodal status. MDCT provides the best results.
Aims
Post-operative urinary retention (POUR) is a common cause of unplanned admission following day-case surgery and has negative effects on both patient and surgical institution. We aimed to ...prospectively evaluate potential risk factors for the development of POUR following day-case general surgical procedures.
Methods
Over a 24-week period, consecutive adult patients undergoing elective day-case general surgery at a single institution were prospectively recruited. Data regarding urinary symptoms, comorbidities, drug history, surgery and perioperative anaesthetic drug use were collected. The primary outcome was the incidence of POUR, defined as an impairment of bladder voiding requiring either urethral catheterisation, unplanned overnight admission or both. Potential risk factors for the development of POUR were analysed by logistic regression.
Results
A total of 458 patients met the inclusion criteria during the study period, and data were collected on 382 (83%) patients (74.3% male). Sixteen patients (4.2%) experienced POUR. Unadjusted analysis demonstrated three significant risk factors for the development of POUR: age ≥ 56 years (OR 7.77 2.18–27.78,
p
= 0.002), laparoscopic surgery (OR 3.37 1.03–12.10,
p
= 0.044) and glycopyrrolate administration (OR 5.56 2.00–15.46,
p
= 0.001). Male sex and lower urinary tract symptoms were not significant factors. Multivariate analysis combining type of surgery, age and glycopyrrolate use revealed that only age ≥ 56 years (OR 8.14 2.18–30.32,
p
= 0.0018) and glycopyrrolate administration (OR 3.48 1.08–11.24,
p
= 0.0370) were independently associated with POUR.
Conclusions
Patients aged at least 56 years and/or requiring glycopyrrolate—often administered during laparoscopic procedures—are at increased risk of POUR following ambulatory general surgery.
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