Mesenchymal cells regulate enteric neural crest cell migration via RET-GFRA1b trans-signaling

During early development, the enteric nervous system forms from the migration of enteric neural crest cells (ENCCs) from the foregut to the hindgut, where they undergo proliferation and differentiation facilitated by interactions with enteric mesenchymal cells (EMCs). This study investigates the impact on ENCC migration of EMC-ENCC communication mediated by GFRA1b expressed in EMCs. GFRA1-expressing cells in day 11-12 (E11-12) mouse embryos differentiated into smooth muscle cells from E12 onwards. Observations at E12-13.5 revealed high levels of GFRA1 expression on the anti-mesenteric side of the hindgut, correlating with enhanced ENCC migration. This indicates that GFRA1 in EMCs plays a role in ENCC migration during development. Examining GFRA1 isoforms, we found high levels of GFRA1b, which lacks amino acids 140-144, in EMCs. To assess the impact of GFRA1 isoforms on EMC-ENCC communication, we conducted neurosphere drop assays. This revealed that GFRA1b-expressing cells promoted GDNF-dependent extension and increased neurite density in ENCC neurospheres. Co-culture of ENCC mimetic cells expressing RET and GFRA1a with EMC mimetic cells expressing GFRA1a, GFRA1b, or vector alone showed that only GFRA1b-expressing co-cultured cells sustained RET phosphorylation in ENCC-mimetic cells for over 120 min upon GDNF stimulation. Our study provides evidence that GFRA1b-mediated cell-to-cell communication plays a critical role in ENCC motility in enteric nervous system development. These findings contribute to understanding the cellular interactions and signaling mechanisms that underlie enteric nervous system formation and highlight potential therapeutic targets for gastrointestinal motility disorders.

Rapidly growing intramuscular lipoma: a unique entity of benign lipomas in children

This report presents a case of an intramuscular lipoma observed in the left back of a healthy female toddler. It was resected after 3 months of observation because of rapid enlargement, raising suspicion of malignancy. Histopathological examination confirmed a diagnosis of intramuscular lipoma without malignant and blastemal components. Intramuscular lipomas are benign neoplasms that mostly appear as a rapidly growing tumour. Several hypotheses regarding the pathogenesis of this characteristic growth pattern have been proposed, including atrophy of the surrounding muscle, reactive adipocytic neoformation and multiple contractive interactions between the lipoma and the surrounding muscle.

The Junction Between the Peristaltic and Non-peristaltic Bowel (Shore Break) is Found in the Transition Zone in Hirschsprung's Disease

BACKGROUND

The junction between the peristaltic and non-peristaltic bowel, which is named the "shore break" (SB), observed on endoscopy is thought to be the boundary between normal and abnormal motility in Hirschsprung's disease (HD). The transition zone (TZ), which is the histopathological border, does not have normal motility and should be resected. This study aimed to evaluate the histopathological findings of the SB and determine the association between the SB and TZ.

METHODS

A retrospective review of surgical specimens of patients with HD who underwent preoperative SB marking was conducted. The TZ was defined if nerve hypertrophy, myenteric hypoganglionosis, or partial circumferential aganglionosis was detected.

RESULTS

Ten patients (9 boys and 1 girl) were studied. The median age at surgery was 30 days. The median distance from the anal verge to the marked SB site was 14 cm. No patients manifested any obstructive symptoms resulting from a residual TZ bowel. In eight patients, nerve hypertrophy was identified at the proximal margin and at the SB. Myenteric hypoganglionosis was identified in three patients at the proximal margin and SB. Partial circumferential aganglionosis was identified at the SB in two patients. As a result, in all patients, the pull-through site and SB site had histopathological features indicating TZ.

CONCLUSIONS

The SB is located in the TZ. Our results suggest that the proximal part of the TZ has normal motility and that functional border points may be present in the TZ.

LEVEL OF EVIDENCE

IV.

Differences in isolated bacteria between perforated and non-perforated appendicitis: an analysis of 680 consecutive appendicectomies in a single institution

PURPOSE

Escherichia coli and Bacteroides species are the most frequently detected species in ascites in perforated appendicitis and are generally sensitive to non-empiric cephalosporins like cefazolin or cefmetazole. However, monotherapy with such antibiotics is mostly insufficient for perforated appendicitis. To investigate this issue, this study aimed to compare bacterial floras in ascites culture between perforated and non-perforated appendicitis.

METHODS

Ascites culture results in perforated and non-perforated appendicitis cases were analyzed using a departmental database. The duration of symptoms before surgery, pre-surgical white blood cell count, C-reactive protein value, postsurgical length of stay, length of antibiotic treatment, and the rate of using second-line antibiotics or complications were also compared.

RESULTS

A total of 608 and 72 cases of non-perforated and perforated appendicitis were included. Escherichia coli and Bacteroides species were the dominant bacteria in both conditions. However, the total proportions of Pseudomonas aeruginosa, Streptococcus anginosus group, and Enterococcus group were significantly higher in perforated appendicitis than in non-perforated appendicitis.

CONCLUSION

Pseudomonas aeruginosa, Streptococcus anginosus group, and Enterococcus group have better susceptibility to penicillin-based empiric antibiotics than cephalosporins. The abundance of these bacteria might explain why non-empiric cephalosporins are not effective in perforated appendicitis and the superiority of penicillin-based empiric antibiotics.

Recipient colon preoperative treatment with type I collagenase and fibronectin promotes the growth of transplanted enteric neural crest cells into Auerbach's plexus

PURPOSE

Cell-based therapy is a potential treatment option for neurointestinal diseases by serving as a source of neural progenitor cells to replace missing or abnormal enteric neurons. Using an ex vivo transplantation model, we recently demonstrated that treatment with collagenase and fibronectin promotes infiltration of transplanted enteric neural crest cells (ENCCs) toward the colon lumen. The aim of this study was to determine whether this new method also promotes colonization of transplanted ENCCs in vivo.

METHODS

Collagenase was applied locally on the anti-mesenteric area of the recipient colon using filter paper, followed by fibronectin. Neurospheres were generated from ENCCs isolated from fetal mouse intestines and transplanted into the collagenase and fibronectin-treated colon. Engraftment of neurospheres was confirmed by immunofluorescence.

RESULTS

Neurospheres transplanted onto PBS- or fibronectin-treated colons were not observed to infiltrate to the muscle layer. However, when used in combination with type I collagenase and fibronectin in the recipient colon, transplanted neurospheres reached Auerbach's plexus.

CONCLUSION

We demonstrated that transplanted neurospheres grow into Auerbach's plexus in the recipient colon pretreated with collagenase and fibronectin.

Level of vascular inflammation is higher in acute coronary syndromes compared to chronic coronary disease

Background

Vascular inflammation has been recognized as one of the key factors in the pathogenesis of acute coronary syndromes (ACS). Peri-coronary adipose tissue (PCAT) attenuation by computed tomography angiography (CTA) has emerged as a marker specific for coronary artery inflammation. We examined the relationship between clinical presentation and coronary artery inflammation assessed by PCAT attenuation and coronary plaque characteristics.

Methods

Patients with ACS or stable angina pectoris (SAP) who underwent pre-intervention coronary CTA and optical coherence tomography (OCT) were enrolled. PCAT attenuation was measured around the culprit lesion and in the proximal 40 mm of all coronary arteries. PCAT attenuation and OCT findings were compared between patients with ACS versus SAP.

Results

Among 471 patients (ACS: 198, SAP: 273), PCAT attenuation was higher in ACS patients than in SAP patients both at the culprit plaque level (−67.5±9.6 Hounsfield unit [HU] vs. −71.5±11.0 HU, p<0.001) and the culprit vessel level (−68.3±7.7 HU vs. −71.1±7.9 HU, p<0.001). The mean PCAT attenuation of all 3 coronary arteries was also significantly higher in ACS patients than in SAP patients (−68.8±6.3 HU vs. −70.5±7.1 HU, p=0.007). After adjusting patient characteristics, not only thin-cap fibroatheroma (OR: 2.44; 95% CI: 1.63–3.65) and macrophages (OR: 2.07; 95% CI: 1.34–3.21) but also PCAT attenuation in the culprit plaque (OR: 1.04; 95% CI: 1.02–1.06) was associated with the clinical presentation of ACS.

Conclusions

PCAT attenuation at culprit plaque, culprit vessel, and pan-coronary levels was higher in ACS patients than in SAP patients. Vascular inflammation appears to play a crucial role in the development of ACS.

Funding Acknowledgement

Type of funding sources: None.

Transplanted neural crest cells migrate toward Auerbach's plexus layer instead of the colon surface in recipient colon pretreated with collagenase and fibronectin

The enteric nervous system (ENS) regulates gastrointestinal motility, secretion, and absorption. Developmental ENS dysplasia causes intestinal ganglion dysfunction, including Hirschsprung's disease. Given their potential ability to replenish insufficient neurons, transplantation of enteric neural cells provides the prospect of a cure. In this study, we used an ex vivo mouse colon transplant model to demonstrate that treatment with collagenase and fibronectin altered the migration of transplanted cells from the direction of the colon surface toward the lumen. Collagenase-treated colons exhibited enhanced expression of type III and VI collagens, which inhibited fibronectin-induced enteric neural crest cell (ENCC) migration. Invasion of neurospheres into colon was dependent on preoperative treatment of recipient colon with collagenase and fibronectin, which enhanced neurosphere motility towards the direction of colon lumen. Infiltration of transplanted ENCCs into the colon increased proportionally to the degree of dedifferentiation of surrounding smooth muscle cells, which was induced in a neurosphere-dependent manner in collagenase-treated colon. Furthermore, induction of GDNF expression, a Ret ligand that promotes enteric neural cell migration, was observed in treated colons. Our results suggest that the environment provided by the extracellular matrix of the colon surface affects the direction of transplanted ENCC migration. Moreover, these findings demonstrating that ENCCs can be accepted by the recipient colon will help to refine current strategies for cell therapy.

Unveiling unconventional magnetism at the surface of Sr2RuO4

Materials with strongly correlated electrons often exhibit interesting physical properties. An example of these materials is the layered oxide perovskite Sr₂RuO₄, which has been intensively investigated due to its unusual properties. Whilst the debate on the symmetry of the superconducting state in Sr₂RuO₄ is still ongoing, a deeper understanding of the Sr₂RuO₄ normal state appears crucial as this is the background in which electron pairing occurs. Here, by using low-energy muon spin spectroscopy we discover the existence of surface magnetism in Sr₂RuO₄ in its normal state. We detect static weak dipolar fields yet manifesting at an onset temperature higher than 50 K. We ascribe this unconventional magnetism to orbital loop currents forming at the reconstructed Sr₂RuO₄ surface. Our observations set a reference for the discovery of the same magnetic phase in other materials and unveil an electronic ordering mechanism that can influence electron pairing with broken time reversal symmetry.

Novel application of infliximab for diversion colitis

Diversion colitis (DC) that was refractory to standard treatments was successfully treated with infliximab. A 24-year-old man with a transverse colostomy suffered from severe DC. Topical steroids, 5-aminosalicylic acid (5-ASA) enemas and synbiotics were initially effective, and the colostomy was successfully closed with a covering ileostomy to minimise the risk of anastomotic leakage owing to the damaged colon. DC subsequently relapsed in the entire colon and was refractory to the previous protocol and autologous faecal transplantation. Intravenous methylprednisolone and oral 5-ASA were discontinued owing to possible adverse effects. Infliximab with intravenous prednisolone was introduced, and the protocol was so effective in suppressing the acute colitis that total colectomy was avoided. The stoma was subsequently closed, and the patient is currently symptom-free. Infliximab is used for ulcerative colitis but could also be effective against severe DC.

Glomerular hyperfiltration with hyperglycemia in the spontaneously diabetic Torii (SDT) fatty rat, an obese type 2 diabetic model

Glomerular hyperfiltration is observed in an early stage of kidney diseases including diabetic nephropathy. A better understanding of pathophysiological changes in glomerular hyperfiltration is essential for development of new therapies to prevent kidney disease progression. In this study, we investigated glomerular changes including glomerular filtration rate (GFR) and glomerular size in the Spontaneously Diabetic Torii (SDT) fatty rat, an obese type 2 diabetic model, and we also evaluated pharmacological effects of the sodium glucose cotransporter 2 inhibitor dapagliflozin on the renal lesions. Dapagliflozin was administered to SDT fatty rats from 5 to 17 weeks of age. Blood and urinary biochemical parameters were periodically measured. GFR was determined by transdermal GFR monitor at 16 weeks of age and histopathological analysis was performed at 17 weeks of age. SDT fatty rat developed severe hyperglycemia and exhibited pathophysiological abnormalities in the kidney, such as an increased GFR, glomerular hypertrophy and tissue lesions. Dapagliflozin achieved good glycemic control during the experimental period, inhibited the increase in GFR, and improved histopathological abnormalities in tubules. These results suggest that the SDT fatty rat is a useful model for analyzing the pathogenesis of diabetic nephropathy during its early stage and dapagliflozin improves not only hyperglycemia but also glomerular hyperfiltration and tubule lesions in SDT fatty rat.

Messenger RNA expression and localization of xenin in the gastrointestinal tract in sheep

The present study aimed to determine the primary sequence of ovine xenin and clarify the mRNA expression and peptide localization of xenin in the gastrointestinal tract in sheep. The colocalization of xenin and glucose-dependent insulinotropic polypeptide was also compared in the antrum and duodenum. Analysis of the nucleotide sequence of ovine xenin revealed a high degree (97.9%) of sequence homology of the sequence between sheep and cattle, and the amino acids sequence determined for ovine xenin coincided (100%) with that of other mammalian species. Real-time quantitative PCR for ovine xenin did not show regional difference in the mRNA expression ratio of xenin. In contrast to the real-time quantitative PCR results, anti-xenin positive cells were abundantly localized in the abomasal antrum (P < 0.01) and at a lesser amount in the duodenum, but no antixenin positive cells were observed in the other regions. Anti-xenin single-positive cells were in a majority in the abomasal antrum, whereas anti-xenin single-positive cells, and anti-GIP single-positive cells, and double-positive cells were even colocalized in the duodenum. These results suggest that abomasal antrum is a major source of xenin in the ovine gastrointestinal tract.

Higher levels of social and material deprivation are associated with higher rates of influenza-like illness-related emergency department visits: Edmonton, Alberta, 2004-2014

OBJECTIVES

Neighbourhood-level deprivation is associated with hospitalization related to respiratory infections; however, hospitalizations exclude many who seek care with less severe respiratory illnesses. Another major seasonal contributor to respiratory illness-associated healthcare burdens are influenza-like illness (ILI)-related emergency department (ED) visits. We investigated associations between area-level social and material deprivation and ILI-related ED use.

STUDY DESIGN

This is a retrospective ecological study.

METHODS

We linked ILI-related ED visit data (2004-2014) for Edmonton, Alberta to a Canadian area-level material and social deprivation index, categorizing deprivation into quintiles. Using a multivariable Poisson model with log population as the offset, we modelled the relationship between visit rates and material and social deprivation adjusting for week and season, age, sex and the interaction between age and sex.

RESULTS

We included 67,585 ILI-related ED visits, representing 1075.5 (95% confidence interval (CI) = 1067.4-1083.6) visits per 100,000 person-years. ILI-related visit rates increased as each of material and social deprivation increased; increases were slightly greater for material deprivation. Comparing the most deprived quintile to the least deprived quintile: for material deprivation, ILI-related ED visit rates were two times higher (rate ratio (RR) = 2.00, 95% CI = 1.96-2.05); and, for social deprivation, one-and-a-half times higher (RR = 1.47, 95% CI = 1.44-1.51).

CONCLUSIONS

Higher area-level material and social deprivation were associated with higher ILI-related ED visit rates. These findings can be used to identify areas that may need additional public health and healthcare resources and to improve targeting of prevention strategies. Understanding differentials in healthcare use such as this may be especially relevant to ensuring equity of outcomes for pandemic preparedness planning.

Arteriovenous malformation that caused prolapse of the colon and was treated surgically in an infant: a case report

Background

Various terms have been used to describe vascular lesions in the intestine, including angiodysplasia, arteriovenous malformation, and telangiectasia. Such lesions are common in adults and are typified by angiodysplasia, a type of arteriovenous malformation. In contrast, these lesions are rarely seen in the pediatric population. Angiodysplasia may cause gastrointestinal bleeding, which is sometimes an indication for treatment. Considering the high rate of recurrence after surgical treatment, conservative treatments are mainly chosen. We herein report an extremely rare case of a prolapsed colon due to an arteriovenous malformation successfully treated by resection in a 1-year-old girl. We also highlight the differences between pediatric and adult cases.

Case presentation

A girl developed bloody stools at 7 months of age. She visited another hospital at 1 year of age because of continuing moderate hematochezia and recent onset of rectal prolapse. Colonoscopy showed a protruding lesion located 15 cm from the anal verge, suggesting a submucosal vascular abnormality. Contrast-enhanced computed tomography and magnetic resonance imaging at our hospital revealed the localized lesion with dilated blood vessels in part of the sigmoid colon; no other lesions were present in the gastrointestinal tract. Laparoscopic-assisted sigmoidectomy was performed. A subserosal vascular lesion was visualized and resected using end-to-end anastomosis. Pathologic examination of the 2.2 × 2.7-cm segment revealed several abnormally enlarged and ectatic blood vessels in the submucosa extending into the subserosa. The lesion was diagnosed as an arteriovenous malformation. The patient had a good clinical course without recurrence at the 2-year follow-up.

Conclusions

An arteriovenous malformation in the sigmoid colon may rarely cause intussusception and prolapse of the colon. Complete resection is a radical and potentially effective treatment. Computed tomography and colonoscopy were useful for evaluation of the lesion in the present case.

Long-term crude probabilities of death among breast cancer patients by age and stage: a population-based survival study in Northeastern Spain (Girona-Tarragona 1985-2004)

Background

We provide population-based long-term survival indicators of breast cancer patients by quantifying the observed survival, and the probabilities of death due to breast cancer and to other causes by age and tumor stage at diagnosis.

Methods

We included a total of 10,195 female patients diagnosed before 85 years with invasive primary breast cancer in Girona and Tarragona during the periods 1985–1994 and 1995–2004 and followed-up until December 31st 2014. The survival indicators were estimated at 5, 10, 15 and 20 years of follow-up comparing diagnostic periods.

Results

Comparing diagnostic periods: I) the probability of death due to other causes did not change; II) the 20-year survival for women diagnosed ≤ 49 years increased 13% (1995–2004 = 68%; 1985–1994:55%), whereas their probability of death due to breast cancer decreased at the same pace (1995–2004 = 29%; 1985–1994 = 42%); III) at 10 years of follow-up, decreases in the probabilities of death due to breast cancer across age groups switched from 11 to 17% resulting in a risk of death reduction of 19% after adjusting by stage. During 1995–2004, the stage-specific 10-year probabilities of death due to breast cancer switched from: 3–6% in stage I, 18–20% in stage II, 34–46% in stage III and surpassed 70% in stage IV beyond 5 years after diagnosis.

Conclusions

In our study, women diagnosed with breast cancer had higher long-term probability to die from breast cancer than from other causes. The improvements in treatment and the lead-time bias in detecting cancer in an early stage resulted in a reduction of 19% in the risk of death between diagnostic periods.

Electronic supplementary material

The online version of this article (10.1007/s12094-018-1852-1) contains supplementary material, which is available to authorized users.

Surgical approach for fecal incontinence with a patulous anus after transanal pull-through for Hirschsprung disease

BACKGROUND

We have performed transanal pull-through (TAPT) for Hirschsprung disease since 1998. Some of our patients after TAPT showed a patulous anus and suffered from severe true fecal incontinence. We performed anal canal plasty for these patients and evaluated its efficacy in restoring anorectal function.

METHODS

Thirty-one patients who were ≥5years old were previously operated on for Hirschsprung disease, and seven (22.5%) of these were indicated for this procedure. Anorectal function was evaluated using the Japanese Study Group of Anorectal Anomalies (JSGA) clinical assessment of defecation function score. For surgery, the patients were positioned in the prone jackknife posture. The posterior half of the anal canal was exposed and folded inward until the anal canal lumen was as narrow as the surgeon's index finger. External anal sphincter muscles were repaired, and the wound was closed vertically.

RESULTS

The mean preoperative JSGA score was 1.42±0.4. The mean JSGA scores at 2-6months and 2years after this procedure were 5±2.1 and 5.8±2.1, respectively. Postoperatively, the JSGA score significantly improved at both times (p<0.05).

CONCLUSIONS

Anal canal plasty may be effective for true fecal incontinence and a patulous anus after TAPT. This surgical approach may be useful for these conditions.

LEVEL OF EVIDENCE

Type of study: Treatment study, Level IV.

Cartilage-hair hypoplasia associated with isolated hypoganglionosis: A case report

Cartilage-hair hypoplasia is a rare metaphyseal chondrodysplasia characterized by diverse clinical manifestations and a high incidence of Hirschsprung disease. We present a male patient with cartilage-hair hypoplasia associated with severe intestinal obstruction. Genetic analysis of ribonuclease mitochondrial RNA-processing complex gene identified compound heterozygous mutations consisted with previously reported mutations: n.-14_3dupGAAGCTGAGGACGTGGT and n.183G > T. First, we considered that intestinal obstruction was due to an extensive type of Hirschsprung disease, but it was later confirmed as isolated hypoganglionosis. Isolated hypoganglionosis is rare and its therapeutic strategies are not well established. In cases of cartilage-hair hypoplasia associated with severe intestinal obstruction, the differential diagnosis of not only Hirschsprung disease, but also isolated hypoganglionosis, should be considered.

Synovial mesenchymal stem cells from osteo- or rheumatoid arthritis joints exhibit good potential for cartilage repair using a scaffold-free tissue engineering approach

OBJECTIVE

To assess whether synovial mesenchymal stem cells (SMSCs) from patients with osteoarthritis (OA) or rheumatoid arthritis (RA) can be used as an alternative cell source for cartilage repair using allogenic tissue engineered construct (TEC).

METHODS

Twenty-five patients (17 female, average age 61.8 years) were divided according to their pathology (control trauma group; N = 6, OA group; N = 6) and RA patients were subdivided into two groups to evaluate the impact of biologics in accordance with whether treated with biologics [Bio(+)RA; N = 7] or not [Bio(-)RA; N = 6]. We compared the following characteristics among these groups: (1) The cell proliferation capacity of SMSCs; (2) The influence of passage number on features of SMSCs; (3) The weight and volume of TEC from the same number of SMSCs; (4) Inflammatory cytokine gene expressions levels of TEC; (5) The chondrogenic potential of TEC; and (6) Osteochondral repair using TEC in athymic nude rats.

RESULTS

SMSCs from the four groups exhibited equivalent features in the above evaluation items. In in vivo studies, the TEC-treated repair tissues for all groups exhibited significantly better outcomes than those for the untreated group and no significant differences among the four TEC groups.

CONCLUSION

SMSCs from OA or RA patients are no less appropriate for repairing cartilage than those from trauma patients and thus, may be an effective source for allogenic cell-based cartilage repair.

Anatomy of the inferior extensor retinaculum and its role in lateral ankle ligament reconstruction: a pictorial essay

The inferior extensor retinaculum (IER) is an aponeurotic structure, which is in continuation with the anterior part of the sural fascia. The IER has often been used to augment the reconstruction of the lateral ankle ligaments, for instance in the Broström-Gould procedure, with good outcomes reported. However, its anatomy has not been described in detail and only a few studies are available on this structure. The presence of a non-constant oblique supero-lateral band appears to be important. This structure defines whether the augmentation of the lateral ankle ligaments reconstruction is performed using true IER or only the anterior part of the sural fascia. It is concluded that the use of this structure will have an impact on the resulting ankle stability.

Survival in stage I-III breast cancer patients by surgical treatment in a publicly funded health care system

BACKGROUND

Recent investigations of breast cancer survival in the United States suggest that patients who receive mastectomy have poorer survival than those who receive breast-conserving surgery (BCS) plus radiotherapy, despite clinically established equivalence. This study investigates breast cancer survival in the publicly funded health care system present in Alberta, Canada.

PATIENTS AND METHODS

Surgically treated stage I-III breast cancer cases diagnosed in Alberta from 2002 to 2010 were included. Demographic, treatment and mortality information were collected from the Alberta Cancer Registry. Unadjusted overall and breast cancer-specific mortality was assessed using Kaplan-Meier and cumulative incidence curves, respectively. Cox proportional hazards models were used to calculate stage-specific mortality hazard estimates associated with surgical treatment received.

RESULTS

A total of 14 939 cases of breast cancer (14 633 patients) were included in this study. The unadjusted 5-year all-cause survival probabilities for patients treated with BCS plus radiotherapy, mastectomy, and BCS alone were 94% (95% CI 93% to 95%), 83% (95% CI 82% to 84%) and 74% (95% CI 70% to 78%), respectively. Stage II and III patients who received mastectomy had a higher all-cause (stage II HR = 1.36, 95% CI 1.13-1.48; stage III HR = 1.74, 95% CI 1.24-2.45) and breast cancer-specific (stage II HR = 1.39, 95% CI 1.09-1.76; stage III HR = 1.79, 95% CI 1.21-2.65) mortality hazard compared with those who received BCS plus radiotherapy, adjusting for patient and clinical characteristics. BCS alone was consistently associated with poor survival.

CONCLUSIONS

Stage II and III breast cancer patients diagnosed in Alberta, Canada, who received mastectomy had a significantly higher all-cause and breast cancer-specific mortality hazard compared with those who received BCS plus radiotherapy. We suggest greater efforts toward educating and encouraging patients to receive BCS plus radiotherapy rather than mastectomy when it is medically feasible and appropriate.

Abstract P4-08-01: Effects of exercise during adjuvant chemotherapy on clinical outcomes in early stage breast cancer

Background: Observational studies suggest that physical activity following a diagnosis of breast cancer may be associated with a lower risk of recurrence and death. Some studies also suggest possible effect modification by disease stage, body mass index, and receptor status. To date, however, there are no randomized trials examining the effects of exercise on disease outcomes in any cancer patient group. Here, we report an exploratory follow-up of disease outcomes from the Supervised Trial of Aerobic versus Resistance Training (START). Patients and Methods: The START Trial was a Canadian multicenter trial that randomized 242 breast cancer patients starting adjuvant chemotherapy to either usual care (n = 82) or supervised aerobic (n = 78) or resistance (n = 82) exercise for the duration of their chemotherapy. The primary efficacy endpoint for this exploratory analysis was disease-free survival (DFS). Secondary endpoints were overall survival (OS), distant disease-free survival (DDFS), and recurrence-free interval (RFI). The two exercise arms were combined for the analysis (n = 160) and selected subgroups were explored. Results: After a median follow-up of 89 months (IQR 81 to 96), there were 25/160 (15.6%) DFS events in the exercise groups and 18/82 (22.0%) in the control group (log-rank p = 0.21). Eight-year DFS was 82.7% for the exercise groups compared with 75.6% for the control group (Hazard ratio [HR] = 0.68, 95% CI = 0.37-1.24). There were 13/160 (8.1%) deaths in the exercise groups and 11/82 (13.4%) in the control group (log-rank p = 0.21). Eight-year OS was 91.2% in the exercise groups compared with 82.7% in the control group (HR = 0.60, 95% CI = 0.27 to 1.33. There were 20/160 (12.5%) DDFS events in the exercise groups and 16/82 (19.5%) in the control group (log-rank p = 0.15). Eight-year DDFS was 86.7% in the exercise groups compared with 78.3% in the control group (HR = 0.62, 95% CI = 0.32 to 1.19). Finally, there were 20/160 (12.5%) RFI events in the exercise groups and 17/82 (20.7%) in the control group (Gray's p = 0.095). Eight-year cumulative incidence of RFI was 12.6% in the exercise groups compared with 21.6% in the control group (HR = 0.58, 95% CI = 0.30 to 1.11). Subgroup analyses for DFS and RFI suggested stronger effects for women who were overweight/obese, had stage II/III cancer, receptor positive tumors, HER2 positive tumors, received taxane-based chemotherapies, and received at least 85% of their intended chemotherapy dose-intensity. The most notable subgroup effect was for patients who received optimal chemotherapy dosing with a borderline significant effect for DFS (HR = 0.50, 95% CI = 0.25 to 1.01) and a significant effect for RFI (HR = 0.38, 95% CI = 0.18 to 0.81). Conclusions: In this exploratory follow-up of the START Trial, there was a suggestion that exercise during adjuvant chemotherapy may improve several efficacy endpoints although none achieved statistical significance. Nevertheless, the magnitude of the effects appear to be meaningful with absolute 8-year survival differences between 7% and 9% and relative rate reductions between 30% and 40%. The START Trial provides the first randomized data to suggest that adding exercise to standard chemotherapy for breast cancer may improve outcomes. A definitive phase III trial is warranted.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-08-01.

Noninvasive estimation of fibrosis progression overtime using the FIB-4 index in chronic hepatitis C

The FIB-4 index is a simple formula to predict liver fibrosis based on the standard biochemical values (AST, ALT and platelet count) and age. We here investigated the utility of the index for noninvasive prediction of progression in liver fibrosis. The time-course alteration in the liver fibrosis stage between paired liver biopsies and the FIB-4 index was examined in 314 patients with chronic hepatitis C. The average interval between liver biopsies was 4.9 years. The cases that showed a time-course improvement in the fibrosis stage exhibited a decrease in the FIB-4 index, and those that showed deterioration in the fibrosis stage exhibited an increase in the FIB-4 index with a significant correlation (P < 0.001). Increase in the ΔFIB-4 index per year was an independent predictive factor for the progression in liver fibrosis with an odds ratio of 3.90 (P = 0.03). The area under the receiver operating characteristic curve of the ΔFIB-4 index/year for the prediction of advancement to cirrhosis was 0.910. Using a cut-off value of the ΔFIB-4 index/year <0.4 or ≥ 0.4, the cumulative incidence of fibrosis progression to cirrhosis at 5 and 10 years was 34% and 59%, respectively in patients with the ΔFIB-4 index/year ≥0.4, whereas it was 0% and 3% in those with the ΔFIB-4 index/year <0.4 (P < 0.001). In conclusion, measurement of the time-course changes in the FIB-4 index is useful for the noninvasive and real-time estimation of the progression in liver fibrosis.

The `genetic benefits' of female multiple mating reconsidered

In many animals, males can generally increase their fitness by mating with many mates, but females cannot produce more offspring than the number of their eggs. In spite of this restriction, females often mate with more than one male. In species without any male-provided resource benefits, females are thought to obtain some `genetic benefits' from males that enhance offspring quality. The evolution of female multiple mating is often confused with the issue of female mate choice, but mate choice is actually possible in the single-mating situation. Therefore, we still need to explain the possible advantage of multiple mating over single mating.

Rates of initial virological suppression and subsequent virological failure after initiating highly active antiretroviral therapy: the impact of aboriginal ethnicity and injection drug use

Objectives:

To compare rates of initial virological suppression and subsequent virological failure by Aboriginal ethnicity after starting highly active antiretroviral therapy (HAART).

Methods:

We conducted a retrospective cohort study of antiretroviral-naïve HIV-patients starting HAART in January 1999-June 2005 (baseline), followed until December 31, 2005 in Alberta, Canada. We compared the odds of achieving initial virological suppression (viral load <500 copies/mL) by Aboriginal ethnicity using logistic regression and, among those achieving suppression, rates of virological failure (the first of two consecutive viral loads > 1000 copies/mL) by Aboriginal ethnicity using cumulative incidence curves and Cox proportional hazards models. Sex, injection drug use as an HIV exposure category (IDU), baseline age, CD4 cell count, viral load, calendar year, and HAART regimen were considered as potential confounders.

Results:

Of 461 study patients, 37% were Aboriginal and 48% were IDUs; 71% achieved initial virological suppression and were followed for 730.4 person-years. After adjusting for confounding variables, compared to non-Aboriginals with other exposures, the odds of achieving initial virological suppression were lower for Aboriginal IDUs (odds ratio (OR)=0.33, 95% CI=0.19-0.60, p=0.0002), non-Aboriginal IDUs (OR=0.30, 95% CI=0.15-0.60, p=0.0006), and Aboriginals with other exposures (OR=0.38, 95% CI=0.21-0.67, p=0.0009). Among those achieving suppression, Aboriginals experienced higher virological failure rates ≥1 year after suppression (hazard ratio=3.35, 95% CI=1.68-6.65, p=0.0006).

Conclusions:

Future research should investigate adherence among Aboriginals and IDUs treated with HAART and explore their treatment experiences to assess ways to improve outcomes.

Referral rate to oncologists and its variation by hospital for colorectal cancer patients

BACKGROUND

Recent population-based studies in Alberta, Canada, found that approximately 50% of patients with stage III colon or stages II/III rectal adenocarcinoma did not receive guideline-recommended treatment (surgery plus chemotherapy or chemoradiation); a primary reason was not having an oncologist consult. We assessed the relationship between the hospital where the surgery was performed and the probability of a patient not having an oncologist consult.

METHODS

All patients diagnosed with stage III colon or stage II/III rectal adenocarcinoma between 2002 and 2005 in Alberta who had surgery were identified from the Alberta Cancer Registry and included in the study. Multivariable logistic regression modeling with hospitals as random effects was used to estimate cancer-type-specific odds ratios of not having an oncologist consult for each hospital, adjusted for age, sex, and comorbidities, relative to the overall nonconsultation rate.

RESULTS

Overall, 21% of stage III colon, 25% of stage II rectal, and 13% of stage III rectal adenocarcinoma patients did not have an oncologist consult. Rates varied appreciably across hospitals and between cancer types within hospitals, even after the case-mix adjustment (adjusted odds ratios of nonconsultation ranged from 0.4 to 8.1). Small hospitals that performed 12 or fewer surgeries had nearly 100% consultation rates.

CONCLUSIONS

The variation in oncologist-consult rates, particularly for stage II rectal cancer patients, is concerning. We are presenting the findings to the surgical community and discussing interventions to improve oncologist-consult rates.

Adherence to treatment guidelines in stage II/III rectal cancer in Alberta, Canada

AIMS

Evidence suggests that pre- and/or postoperative treatment benefits patients with stage II/III rectal cancer. This study aimed to quantify treatment patterns and adherence to treatment guidelines, and to identify barriers to having a consultation with an oncologist and barriers to receiving treatment in stage II/III rectal cancer, in a publicly funded medical care system.

MATERIALS AND METHODS

Patients with surgically treated stage II/III rectal adenocarcinoma, diagnosed from 2002 to 2005 in Alberta, a Canadian province with a population of 3 million, were included. Demographic and treatment information from the Alberta Cancer Registry were linked to data from electronic medical records, hospital discharge data and the 2001 Canadian Census. The study outcomes were 'not having an oncologist consultation' and 'not receiving guideline-based treatment'. The relative risks of the two outcomes in association with patient characteristics were estimated using multivariable log-binomial regression.

RESULTS

Of a total of 910 surgically treated stage II/III rectal adenocarcinoma patients, 748 (82%) had a consultation with an oncologist and 414 (45.5%) received treatment. Pre-/post-surgical treatment modalities and timing varied; 96 (10.5%) received neoadjuvant treatment only, 389 (42.7%) received adjuvant treatment only, 119 (13.1%) received both, and 306 (33.6%) had surgery alone. Factors related to not having a consultation with an oncologist included older age, co-morbidities, cancer stage II and region of residence. Older age was the most significantly associated factor with not receiving treatment (relative risk=2.23; 95% confidence interval: 1.89, 2.64).

CONCLUSIONS

Disparities exist in the receipt of treatment in stage II/III rectal cancer. Factors such as age, region of residence and stage should not be barriers to consulting an oncologist to discuss or receive treatment. The reasons for these disparities need to be identified and addressed.

Glucose-lowering agents and cancer mortality rates in type 2 diabetes: assessing effects of time-varying exposure

AIMS/HYPOTHESIS

We explored the relationship between glucose-lowering agents and cancer mortality rates in type 2 diabetes patients, hypothesising a decreased risk of cancer mortality with metformin use and a dose-risk gradient for insulin therapy.

METHODS

This was a population-based cohort study using administrative data from Saskatchewan Health, Canada. We identified new users of metformin or sulfonylureas from 1 January 1991 to 31 December 1996, with follow-up until death, departure from the province or 31 December 1999. Cox regression analyses were used to estimate the HR of death from cancer, accounting for time-varying exposure to metformin, sulfonylurea, and exogenous insulin therapy.

RESULTS

We identified 10,309 new users of metformin or sulfonylurea. The average follow-up was 5.4 (1.9) years, during which 407 (4.0%) cancer deaths occurred. Adjusting for age, sex and chronic disease score, the adjusted HR for metformin use was 0.80 (95% CI 0.65-0.98) compared with sulfonylurea monotherapy users. Adjusted HRs for subsequent insulin use were 2.22 (0.99-5.00), 3.33 (2.26-4.89) and 6.40 (4.69-8.73) for <3, 3 to 11 and > or = 12 insulin dispensations/year, respectively, compared with patients not on insulin. We observed a similar risk gradient among the sub-cohort of new insulin users.

CONCLUSIONS/INTERPRETATION

Our results support previous reports of a decreased risk of cancer outcomes associated with metformin use relative to sulfonylurea monotherapy. We also provide new evidence of a gradient of cumulative insulin dispensations and cancer mortality rates.

Clinical features of cases of influenza A (H1N1)v in Osaka prefecture, Japan, May 2009

This report describes the clinical characteristics of influenza A(H1N1)v virus infection in Osaka. By the end of May, 171 cases had been reported in Osaka. Most patients were from one school. No patient had a serious underlying medical condition.Clinical symptoms were mild and resembled those of seasonal influenza. The sensitivity of the rapid antigen test was 77%. Antivirals were given to the majority of the cases. Early antiviral treatment may have shortened the duration of fever.

Epidemiology of influenza A(H1N1)v virus infection in Japan, May - June 2009

Between 9 May and 4 June 2009, a total of 401 laboratory-confirmed cases of influenza A(H1N1)v virus were reported in Japan, from 16 of the 47 Japanese prefectures. The two areas most affected were Osaka prefecture and Kobe city where outbreaks in high schools occurred leading to school closures. To date all cases have had symptoms consistent with seasonal influenza and no severe or fatal cases have been reported.

The virtues of a deliberately mis-specified disease model in demonstrating a gene-environment interaction

OBJECTIVES

This study seeks to assess the impact of measurement errors in cumulative exposure on estimates of a gene-environment interaction in a nested case-control study in occupational epidemiology. In the approach considered here, exposure intensity is assessed at the group level and the exposure duration individually (both with error). Genetic susceptibility is assumed to be known exactly. Differences in "gene" are assumed to affect disease risk only in exposed subjects.

METHODS

Three data analysis strategies were considered: one using a correctly specified disease model (exposure and exposure-gene interaction), and two using mis-specified disease models, one with "gene" as the only risk factor ("gene-only" model) and the other with main effects of both gene and exposure along with their interaction ("full" model).

RESULTS

In simulations, estimates of the gene-environment interaction based on the correctly specified disease model were greatly attenuated and power was diminished appreciably even when errors in exposure were modest. Significant associations were detected more frequently in the gene-only model when errors in exposure were large. When the "full" mis-specified model was fitted to the simulated data, it yielded erratic estimates. This is illustrated in an analysis of the interaction of cumulative exposure to organophosphate pesticides and paraoxonase gene on the risk of chronic neuropsychological effects among farmers who dip sheep.

CONCLUSION

If "gene" contributes to disease risk only in the presence of exposure, the existence of the gene-environment interaction can be efficiently inferred from a deliberately mis-specified "gene-only" disease model in nested case-control studies.

Pathway analysis of microarray data via regression

Pathway analysis of microarray data evaluates gene expression profiles of a priori defined biological pathways in association with a phenotype of interest. We propose a unified pathway-analysis method that can be used for diverse phenotypes including binary, multiclass, continuous, count, rate, and censored survival phenotypes. The proposed method also allows covariate adjustments and correlation in the phenotype variable that is encountered in longitudinal, cluster-sampled, and paired designs. These are accomplished by combining the regression-based test statistic for each individual gene in a pathway of interest into a pathway-level test statistic. Applications of the proposed method are illustrated with two real pathway-analysis examples: one evaluating relapse-associated gene expression involving a matched-pair binary phenotype in children with acute lymphoblastic leukemia; and the other investigating gene expression in breast cancer tissues in relation to patients' survival (a censored survival phenotype). Implementations for various phenotypes are available in R. Additionally, an Excel Add-in for a user-friendly interface is currently being developed.