Recurrence and cancer-specific death after adjuvant chemotherapy for Stage III colon cancer

AIM

The recommended standard of care for patients after resection of Stage III colon cancer is adjuvant 5-fluorouracil based chemotherapy - FOLFOX (fluorouracil, leucovorin with oxaliplatin) - or CAPOX (capecitabine, oxaliplatin). This may be modified in older patients or depending on comorbidity. This has been challenged recently as the apparent benefit of adjuvant chemotherapy may arise from improvements in surgery or preoperative imaging or pathology staging. This study compares recurrence and colon-cancer-specific death between patients who received postoperative adjuvant chemotherapy and those who did not.

METHOD

Prospectively recorded data from 363 consecutive patients who had a resection for Stage III colonic adenocarcinoma between 1995 and 2010 inclusive were analysed. Surviving patients were followed for at least 5 years. The suitability of patients for chemotherapy was discussed routinely at multidisciplinary team meetings. The incidence of recurrence and colon-cancer-specific death was evaluated by competing risk methods.

RESULTS

After adjustment for the competing risk of non-colorectal cancer death, there was no significant difference in recurrence between the 204 patients who received chemotherapy and the 159 who did not [hazard ratio (HR) 0.94, 95% CI 0.66-1.32, P = 0.700) and no significant difference in colon-cancer-specific death (HR 0.73, 95% CI 0.50-1.04, P = 0.084; HR 0.88, 95% CI 0.57-1.36, P = 0.577 after adjustment for relevant covariates).

CONCLUSION

These findings question the routine use of chemotherapy after complete mesocolic excision for Stage III colon cancer. Recurrence and cancer-specific death, assessed by competing risk methods, should be the standard outcomes for evaluating the effectiveness of adjuvant chemotherapy after potentially curative resection.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Cutaneous mucinosis of infancy: report of a rare case and review of the literature

Cutaneous mucinosis of infancy (CMI) is a rare dermatologic condition, first reported in 1980 and currently classified within the complex group of papular mucinoses. We report a case of CMI and review the prior 13 cases in the literature. The patient was a 5-year-old girl who presented with asymptomatic dermal papules and plaques on her leg and back with no overlying color change. These lesions were first noticed during infancy and had become slightly more evident over time. The patient had a history of birthmarks and eczema. Her family history included eczema, allergies, photosensitivity, and Graves disease. Pre-biopsy clinical differential diagnosis included connective tissue nevus, granuloma annulare, myofibroma, lipofibroma, and lymphangioma. Biopsies revealed significant increase in interstitial mucin within the reticular and mid dermis, without significant sclerosis or fibroblastic proliferation. The relatively quiescent pattern of interstitial mucinosis with slight fibrocyte hyperplasia presenting as dermal papules-plaques on the trunk and extremities was most consistent with a diagnosis of CMI. We report another case of CMI in an otherwise healthy patient. Our patient is unique as she is the first CMI patient with a family history of Graves disease, although our patient appeared euthyroid. We will also review the literature on this rare entity.

Elk (Cervus elaphus) railway mortality in Ontario

Wildlife railway research is highly underrepresented in science despite documented wildlife–train collision mortalities. Gathering baseline information is imperative to the development of effective train collision mitigation, especially for at-risk or small reintroduced populations such as elk (Cervus elaphus Linnaeus, 1758) in eastern North America. We tested our hypotheses that elk–train collision rates vary in relation to railway structure and weather by using a combination of radiotelemetry and railway mortality surveys. Elk were closer to the railway in winter than in any other season. Elk–train collision sites were significantly closer to the apex of bends in the railway than random locations along the railway, and collision rates were positively related to snow depth. Railways may be perceived by elk as easy travel corridors, and deep snow likely prohibits escape from oncoming trains. This study gathered important information about an under-studied aspect of wildlife–human conflicts and provides a basis for the investigation of other species that may be affected by railways.

Tail-Anchored Protein Insertion by a Single Get1/2 Heterodimer

The Get1/2 transmembrane complex drives the insertion of tail-anchored (TA) proteins from the cytosolic chaperone Get3 into the endoplasmic reticulum membrane. Mechanistic insight into how Get1/2 coordinates this process is confounded by a lack of understanding of the basic architecture of the complex. Here, we define the oligomeric state of full-length Get1/2 in reconstituted lipid bilayers by combining single-molecule and bulk fluorescence measurements with quantitative in vitro insertion analysis. We show that a single Get1/2 heterodimer is sufficient for insertion and demonstrate that the conserved cytosolic regions of Get1 and Get2 bind asymmetrically to opposing subunits of the Get3 homodimer. Altogether, our results define a simplified model for how Get1/2 and Get3 coordinate TA protein insertion.

Pre-operative anaemia, intra-operative hepcidin concentration and acute kidney injury after cardiac surgery: a retrospective observational study

Acute kidney after cardiac surgery is more common in anaemic patients, whereas haemolysis during cardiopulmonary bypass may lead to iron-induced renal injury. Hepcidin promotes iron sequestration by macrophages: hepcidin concentration is reduced by anaemia and increased by inflammation. We analysed the associations in 525 patients between pre-operative anaemia (haemoglobin < 130 g.l^-1 in men and < 120 g.l^-1 in women), intra-operative hepcidin concentration and acute kidney injury (dialysis or > 26.4 μmol.l^-1 or > 50% creatinine increase during the first two days after cardiac surgery. Rates of pre-operative anaemia and postoperative kidney injury were 109/525 (21%) and 36/525 (7%), respectively. The median (IQR [range]) intra-operative hepcidin concentration was 20 (10-33 [0-125]) μg.l^-1 and was lower in anaemic patients than those who were not: 15 (4-28 [0-125]) μg.l^-1 vs. 21 (12-33 [0-125]) μg.l^-1 , respectively, p = 0.002. Four variables were independently associated with postoperative kidney injury, for which the beta-coefficients (SE) were: minutes on cardiopulmonary bypass, 0.016 (0.004), p < 0.001; intra-operative hepcidin concentration, 0.032 (0.008), p < 0.001; pre-operative anaemia, 1.97 (0.56), p < 0.001; and Cleveland clinic risk score, 0.88 (0.35), p = 0.005. Contrary to generally increased rates of kidney injury in patients with higher hepcidin concentrations, rates of kidney injury in anaemic patients were lower in patients with higher hepcidin concentrations, beta-coefficient (SE) -0.037 (0.01), p = 0.007. In cardiac surgical patients the rate of postoperative acute kidney injury predicted by the Cleveland risk score might be adjusted for pre-operative anaemia and intra-operative cardiopulmonary bypass time and hepcidin concentration. Pre-operative correction of anaemia, reduction in intra-operative bypass time and modification of iron homeostasis and hepcidin concentration might reduce acute kidney injury.

A Survey of Medical Social Services in Local Accident and Emergency Departments

This study is a structured questionnaire survey on all doctors and nurses working in 14 local Accident & Emergency Departments (EDs) on medical social services. The objectives of this study are to find out: (1) service provision and referral patterns in local EDs; (2) perceptions of doctors and nurses on the present service. In addition to routine referrals during office hours, nearly half of the respondents reported availability of on-site services per request, phone consults during office hours, and support during disaster activation. The most common social problems that doctors would refer to medical social service included child abuse, battered spouse, rape/sexual assault, deliberate self-harm and elderly patients with discharge problem. Over half of the doctors and nurses said the existing services were inadequate and the main shortcoming was no after office hours coverage. In cases of crisis intervention, 56% of doctors and 36% of nurses felt that medical social workers would only be helpful if they were available at short notice most time of the day. To improve the existing service, 62% of doctors and 43% of nurses thought that medical social workers should provide adequate feedback. Other areas for improvement included on-site service, 24-hour coverage and more experienced workers. (Hong Kong j.emerg.med. 2001;8:135–139)

Hepatitis B surface antigen loss and sustained viral suppression in Asian chronic hepatitis B patients: A community-based real-world study

Community-based real-world outcomes on effectiveness of antiviral therapies for chronic hepatitis B virus (CHB) in Asians are limited. Whether hepatitis B surface antigen (HBsAg) loss correlates with undetectable virus and alanine aminotransferase (ALT) normalization on treatment or what predicts risk of seroreversion or detectable virus after stopping therapy is unclear. We aim to evaluate rates and predictors of HBsAg loss, seroconversion, ALT normalization and undetectable HBV DNA, including HBsAg seroreversion or re-emergence of HBV DNA among Asian CHB patients. We retrospectively evaluated 1072 CHB adults on antiviral therapy at two community gastroenterology clinics from 1997 to 2015. Rates of HBsAg loss, ALT normalization, achieving undetectable HBV DNA and developing surface antibody (anti-HBs) were stratified by HBeAg status. Following HBsAg loss, HBsAg seroreversion or re-emergence of detectable HBV DNA was analysed. With median treatment of 76.7 months, the overall rate of HBsAg loss was 4.58%, with similar HBsAg loss rates between HBeAg-positive and HBeAg-negative patients (4.44% vs 4.71%, P=.85) in a predominantly Asian population (98.1%). Among HBsAg loss patients, 33.3% developed anti-HBs, 95.8% achieved undetectable virus and 66.0% normalized ALT. No significant baseline or on-treatment predictors of HBsAg loss were observed. While six patients who achieved HBsAg loss had seroreversion with re-emergence of HBsAg positivity, viral load remained undetectable, demonstrating the sustainability of viral suppression. Among a large community-based real-world cohort of Asian CHB patients treated with antiviral therapy, rate of HBsAg loss was 4.58%. Despite only 33.3% of HBsAg loss patients achieving anti-HBs, nearly all patients achieved sustained undetectable virus.

Microbial acceleration of aerobic pyrite oxidation at circumneutral pH

Pyrite (FeS₂ ) is the most abundant sulfide mineral on Earth and represents a significant reservoir of reduced iron and sulfur both today and in the geologic past. In modern environments, oxidative transformations of pyrite and other metal sulfides play a key role in terrestrial element partitioning with broad impacts to contaminant mobility and the formation of acid mine drainage systems. Although the role of aerobic micro-organisms in pyrite oxidation under acidic-pH conditions is well known, to date there is very little known about the capacity for aerobic micro-organisms to oxidize pyrite at circumneutral pH. Here, we describe two enrichment cultures, obtained from pyrite-bearing subsurface sediments, that were capable of sustained cell growth linked to pyrite oxidation and sulfate generation at neutral pH. The cultures were dominated by two Rhizobiales species (Bradyrhizobium sp. and Mesorhizobium sp.) and a Ralstonia species. Shotgun metagenomic sequencing and genome reconstruction indicated the presence of Fe and S oxidation pathways in these organisms, and the presence of a complete Calvin-Benson-Bassham CO₂ fixation system in the Bradyrhizobium sp. Oxidation of pyrite resulted in thin (30-50 nm) coatings of amorphous Fe(III) oxide on the pyrite surface, with no other secondary Fe or S phases detected by electron microscopy or X-ray absorption spectroscopy. Rates of microbial pyrite oxidation were approximately one order of magnitude higher than abiotic rates. These results demonstrate the ability of aerobic microbial activity to accelerate pyrite oxidation and expand the potential contribution of micro-organisms to continental sulfide mineral weathering around the time of the Great Oxidation Event to include neutral-pH environments. In addition, our findings have direct implications for the geochemistry of modern sedimentary environments, including stimulation of the early stages of acid mine drainage formation and mobilization of pyrite-associated metals.