ORE identifies extreme expression effects enriched for rare variants

MOTIVATION

Non-coding rare variants (RVs) may contribute to Mendelian disorders but have been challenging to study due to small sample sizes, genetic heterogeneity and uncertainty about relevant non-coding features. Previous studies identified RVs associated with expression outliers, but varying outlier definitions were employed and no comprehensive open-source software was developed.

RESULTS

We developed Outlier-RV Enrichment (ORE) to identify biologically-meaningful non-coding RVs. We implemented ORE combining whole-genome sequencing and cardiac RNAseq from congenital heart defect patients from the Pediatric Cardiac Genomics Consortium and deceased adults from Genotype-Tissue Expression. Use of rank-based outliers maximized sensitivity while a most extreme outlier approach maximized specificity. Rarer variants had stronger associations, suggesting they are under negative selective pressure and providing a basis for investigating their contribution to Mendelian disorders.

AVAILABILITY AND IMPLEMENTATION

ORE, source code, and documentation are available at https://pypi.python.org/pypi/ore under the MIT license.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Cross-Canada differences in early-stage breast cancer treatment and acute-care use

Background

Chemotherapy has improved outcomes in early-stage breast cancer, but treatment practices vary, and use of acute care is common. We conducted a pan-Canadian study to describe treatment differences and the incidence of emergency department visits (edvs), edvs leading to hospitalization (edvhs), and direct hospitalizations (hs) during adjuvant chemotherapy.

Methods

The cohort consisted of women diagnosed with early-stage breast cancer (stages i-iii) during 2007-2012 in British Columbia, Manitoba, Ontario, or Nova Scotia who underwent curative surgery. Parallel provincial analyses were undertaken using linked clinical, registry, and administrative databases. The incidences of edvs, edvhs, and hs in the 6 months after treatment initiation were examined for patients treated with adjuvant chemotherapy.

Results

The cohort consisted of 50,224 patients. The proportion of patients who received chemotherapy varied by province, with Ontario having the highest proportion (46.4%), and Nova Scotia, the lowest proportion (38.0%). Age, stage, receptor status, comorbidities, and geographic location were associated with receipt of chemotherapy in all provinces. Ontario had the highest proportion of patients experiencing an edv (36.1%), but the lowest proportion experiencing h (6.4%). Conversely, British Columbia had the lowest proportion of patients experiencing an edv (16.0%), but the highest proportion experiencing h (26.7%). The proportion of patients having an edvh was similar across provinces (13.9%-16.8%). Geographic location was associated with edvs, edvhs, and hs in all provinces.

Conclusions

Intra- and inter-provincial differences in the use of chemotherapy and acute care were observed. Understanding variations in care can help to identify gaps and opportunities for improvement and shared learnings.

The role of scientific evidence in decisions to adopt complex innovations in cancer care settings: a multiple case study in Nova Scotia, Canada

Background

Health care delivery and outcomes can be improved by using innovations (i.e., new ideas, technologies, and practices) supported by scientific evidence. However, scientific evidence may not be the foremost factor in adoption decisions and is rarely sufficient. The objective of this study was to examine the role of scientific evidence in decisions to adopt complex innovations in cancer care.

Methods

Using an explanatory, multiple case study design, we examined the adoption of complex innovations in five purposively sampled cases in Nova Scotia, Canada. Data were collected via documents and key informant interviews. Data analysis involved an in-depth analysis of each case, followed by a cross-case analysis to develop theoretically informed, generalizable knowledge on the role of scientific evidence in innovation adoption that may be applied to similar settings and contexts.

Results

The analyses identified key concepts alongside important caveats and considerations. Key concepts were (1) scientific evidence underpinned the adoption process, (2) evidence from multiple sources informed decision-making, (3) decision-makers considered three key issues when making decisions, and (4) champions were essential to eventual adoption. Caveats and considerations related to the presence of urgent problems and short-term financial pressures and minimizing risk.

Conclusions

The findings revealed the different types of issues decision-makers consider while making these decisions and why different sources of evidence are needed in these processes. Future research should examine how different types of evidence are legitimized and why some types are prioritized over others.

Electronic supplementary material

The online version of this article (10.1186/s13012-019-0859-5) contains supplementary material, which is available to authorized users.

Patterns of cancer centre follow-up care for survivors of breast, colorectal, gynecologic, and prostate cancer

Background

Rising demand on cancer system resources, alongside mounting evidence that demonstrates the safety and acceptability of primary care-led follow-up care, has resulted in some cancer centres discharging patients back to primary care after treatment. At the same time, the ways in which routine cancer follow-up care is provided across Canada continue to vary widely. The objectives of the present study were to investigate patterns of routine follow-up care at a cancer centre for breast, colorectal, gynecologic, and prostate cancer survivors; factors associated with receipt of follow-up care at a cancer centre; and changes in follow-up care at a cancer centre over time.

Methods

We identified all people diagnosed in Nova Scotia with an invasive breast, colorectal, gynecologic, or prostate cancer between 1 January 2006 and 31 December 2013. We linked the resulting population-based dataset, at the patient level, to cancer centre or clinic data and to census data. We identified a nonmetastatic survivor cohort (n = 12,267) and developed decision rules to differentiate routine from non-routine visits during the follow-up care period (commencing 1 year after diagnosis). Descriptive statistics were computed to describe the patterns of routine follow-up care at a cancer centre. Negative binomial regression was used to examine factors associated with visits made and changes over time.

Results

Nearly half the survivors (48.4%) had at least 1 follow-up visit to the cancer centre, with variation by disease site (range: 30.2%-62.4%). Disease site and stage at diagnosis were associated with receipt of follow-up care at a cancer centre. For instance, compared with breast cancer survivors, survivors of gynecologic cancer had more visits [incidence rate ratio (irr): 1.48; 95% confidence interval (ci): 1.34 to 1.64], and survivors of colorectal cancer had fewer visits (irr: 0.45; 95% ci: 0.40 to 0.51). Year of diagnosis was associated with follow-up at a cancer centre, with each successive calendar year being associated with an 8% increase in visits made (irr: 1.08; 95% ci: 1.07 to 1.10).

Conclusions

Despite evidence that follow-up care can be effectively and safely delivered in primary care, and despite intensifying demands on oncology services, many survivors continue to receive routine follow-up care at a cancer centre.

Clinical information available to oncologists in surgically treated rectal cancer: room to improve

INTRODUCTION

In rectal cancer, decisions about the use of adjuvant and neoadjuvant treatment rely on clinical information from a variety of sources. Currently, the quality and accuracy of the aggregate of this clinical information is unclear. The objectives of the present study were to evaluate the completeness and quality of clinical information available to oncologists managing rectal cancer.

METHODS

All patients diagnosed with rectal cancer in Nova Scotia between 2001 and 2005 were identified through the provincial cancer registry. The registry was linked to other administrative databases to obtain demographic, diagnostic, and treatment data. Patients undergoing radiation oncology consultation were identified, and a standardized review of the cancer centre chart was performed on a random sample, stratified by year.

RESULTS

For the 222 patients reviewed, the relevant endoscopy report was present in 113 cases (51%). The level of the tumour was documented in 75% of those reports, and colonoscopy completeness, in 81%. The relevant operative report was available in 192 cases (87%). Tumour level was described in 59% of those reports, and local extension, in 73%. Elements of total mesorectal excision were partially described in 97%. In pathology reports (10% of which were synoptic), we observed significant variability in the presence of important elements. Reporting of those elements was significantly better in the synoptic pathology reports.

CONCLUSIONS

Clinical information related to adjuvant and neoadjuvant therapy decision-making in rectal cancer is often not available or incomplete. A synoptic reporting system in endoscopy, surgery, and pathology could potentially be a beneficial tool in rectal cancer care.

Access to care and patient satisfaction for surgically-treated breast cancer

17010

Background: Although recent studies have described timeliness of breast cancer (BC) care and its impact on outcomes, there is little data on patient perception of timeliness. This study examined the association between clinicodemographic factors, timeliness and patient satisfaction for surgically-treated BC patients across defined intervals of diagnosis (Dx) and treatment. Methods: All patients undergoing surgery for primary BC within a single Health District over 24 months were enrolled in a prospective consecutive cohort study. A comprehensive, standardized method of ascertaining specific time intervals, including a patient interview, was used to quantify the timeliness of presentation, Dx and treatment. A validated satisfaction questionnaire was applied to patients 2 weeks after surgery, and following chemotherapy. Multiple linear regression, using the natural logarithm of the time interval as the dependant variable, was performed to examine the association of factors and satisfaction with specific time intervals. Results: Among the 519 patients in the study, 317 (61%) were screen-detected and 202 (39%) presented symptomatically. Complete satisfaction questionnaire responses were obtained in 348 (67%). The median time intervals in days (interquartile range) were: abnormal screen to Dx - 33 (21–48); symptoms to Dx 44 (23–97); Dx to surgery - 31 (22–43); surgery to adjuvant chemotherapy 63 (49–73). On multivariate analysis, the interval from presentation (either abnormal mammogram or symptoms) to Dx was 33% longer for screen-detected patients (p<0.0001) and 38% longer for patients where more than one diagnostic test was performed (p=0.009). Moderate correlation was identified between patient satisfaction and both the intervals from presentation to Dx (r2=0.212;p<0.0001) and from Dx to surgery (r2=0.262;p<0.0001). Controlling for the length of these intervals, younger women (p=0.01) and those with a Dx made via screening (p=0.004) had significantly lower satisfaction scores. Conclusions: The timeliness of care for BC involves several defined components; variations in the relatively short interval from Dx to surgery appeared to have most impact on patient satisfaction. Younger women and those diagnosed via screening were less satisfied with their access to timely care.

No significant financial relationships to disclose.

Obesity and lifestyle risk factors for gastroesophageal reflux disease, Barrett esophagus and esophageal adenocarcinoma

The aim of this study was to examine the association of obesity with esophageal adenocarcinoma, and with the precursor lesions Barrett esophagus and gastroesophageal reflux disease (GERD). This case-control study included cases with GERD (n = 142), Barrett esophagus (n = 130), and esophageal adenocarcinoma (n = 57). Controls comprised 102 asymptomatic individuals. Using logistic regression methods, we compared obesity rates between cases and controls adjusting for differences in age, gender, and lifestyle risk factors. Relative to normal weight, obese individuals were at increased risk for esophageal adenocarcinoma (Odds Ratio [OR] 4.67, 95% Confidence Interval [CI] 1.27-17.9). Diets high in vitamin C were associated with a lower risk for GERD (OR 0.40, 95% CI 0.19-0.87), Barrett esophagus (OR 0.44, 95% CI 0.20-0.98), and esophageal adenocarcinoma (OR 0.21, 95% CI 0.06-0.77). For the more established risk factors, we confirmed that smoking was a significant risk factor for esophageal adenocarcinoma, and that increased liquor consumption was associated with GERD and Barrett esophagus. In light of the current obesity epidemic, esophageal adenocarcinoma incidence rates are expected to continue to increase. Successful promotion of healthy body weight and diets high in vitamin C may substantially reduce the incidence of this disease.

Timely access to care for colorectal cancer (CRC): A description and analysis of associated factors

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Background: There are multiple points in the presentation, diagnosis and treatment of CRC where access to physicians and/or medical services may affect the timeliness of appropriate care. A single interval, such as time from diagnosis to surgery, may incompletely reflect the timeliness of care in CRC. We describe the various components of access to care for resectable CRC, and identify factors associated with variation in such components. Methods: From 02/15/2002 to 02/15/2004, all patients undergoing surgery for primary CRC within a single health district were enrolled in a prospective consecutive cohort study. A comprehensive, standardized method of ascertaining specific time intervals, including a patient interview, was used to quantify the timeliness of presentation, diagnosis and surgery. Differences in these time intervals according to demographic and clinical factors were examined using multivariate linear regression. Results: Among the 455 patients in the study cohort, the median time intervals (interquartile range) for the various components of access to care were as follows: symptoms to first physician visit - 36 days (12–79); first physician visit to diagnosis - 51 days (15–127); diagnosis to surgery - 23 days (10–39). On multivariate analysis, the interval from initial symptoms to first physician visit was 96% longer for patients < 50 years (p = 0.02) and 144% longer for rectal lesions (p < 0.001). The interval from first physician visit to diagnosis was 190% longer for patients < 50 years (p < 0.001), and was positively correlated with gross household income (p = 0.02). The interval from diagnosis to surgery was 33% longer in females (p = 0.003) and 70% longer for rectal lesions (p < 0.001). None of these intervals were found to vary significantly according to geographic residence, education level, body mass index, number of years with family doctor, smoking history, or previous use of CRC screening. Conclusions: The timeliness of access to care for CRC involves several defined components; the longest interval is from initial physician visit to diagnosis. Although associated factors vary somewhat according to the specific interval, interventions aimed at improving the timeliness of access to care in CRC should address younger patients and those with rectal cancer.

No significant financial relationships to disclose.

Evolution and critical appraisal of anastomotic technique following resection of esophageal adenocarcinoma

The aim of this study was to critically evaluate acute and long-term complications of hand-sewn and semimechanical cervical esophagogastric anastomosis following resection of primary esophageal adenocarcinoma. Between February 1991 and 2001, 91 consecutive patients underwent subtotal esophagectomy (transthoracic, n=49; transhiatal, n=42), transposing a gastric tube based on the right gastroepiploic artery. All esophagogastric anastomoses were performed in the left neck using a hand-sewn technique (n=53) and, from September 1997, a side-to-side semimechanical technique (n=38). Outcomes evaluated were anastomotic leak rates, length of stay, and development of strictures. Postoperative mortality was 4.4% (all cardiopulmonary causes). Fifty-eight patients (63.7%) had an uncomplicated postoperative course, with a median postoperative length of stay of 10 days (vs. 20 days with associated morbidity; P </= 0.001). Anastomotic leaks were the leading cause of postoperative morbidity (16.5%, 15/91), and were classified into four types based on severity. The semimechanical anastomotic technique was associated with a reduced leak rate compared with the hand-sewn technique (7.9%, 3/38 vs. 22.6%, 12/53; P=0.08), although different patterns of anastomotic failure were seen following semimechanical anastomoses, with increased mediastinal and pleural sepsis. Anastomotic strictures developed in nine (17.0%) hand-sewn and three (7.9%) semimechanical anastomoses. Our conclusion was that a semimechanical technique for cervical esophagogastrostomy is associated with reduced anastomotic leak rates compared with hand-sewn anastomoses, resulting in a shorter postoperative stay. Patterns of anastomotic failure varied between each technique, possibly as a consequence of a longer cervical esophageal segment required for construction of a semimechanical anastomosis. The association between anastomotic technique and stricture development was not clear from this study.

Hepatitis B or C virus serology as a prognostic factor in patients with hepatocellular carcinoma

It is not clear whether chronic hepatitis B or C virus (HBV or HCV) infection is a prognostic factor for hepatocellular carcinoma. We performed this study to determine if chronic HBV or HCV infection had any impact on postresection survival or affected patterns of failure. The records of 77 patients undergoing surgical resection for hepatocellular carcinoma between January 1990 and December 1998 were reviewed. Forty-four patients (57%) had HCV infection, 18 patients (23%) had HBV infection, and 15 patients (20%) had negative serology. There were no differences in age, sex, or tumor size among the groups, and all patients had margin-negative resections. There was a significantly higher incidence of satellitosis and vascular invasion in patients with HCV infection (32% and 41% respectively; P <0.05 vs. other groups). With a median follow-up of 30 months, a significantly decreased local disease-free survival (LDFS) was seen in HBV-positive (5-year LDFS 26%) or HCV-positive (5-year LDFS 38%) patients compared to those with negative serology (5-year LDFS 79%; P <0.05). There was also a trend toward a decreased overall survival in patients with positive hepatitis serology compared to patients with negative serology (37% vs. 79%; P = 0.12). Univariate analysis revealed that only satellitosis was related to local recurrence and overall survival. Patients with positive serology for hepatitis B or C undergoing resection for hepatocellular carcinoma have a trend toward worse overall prognosis and a significantly decreased LDFS when compared to patients with negative serology.

Ontogeny of humoral heart rate regulation in the embryonic mouse

Catecholamines, acetylcholine, and adenosine are known to influence cardiac function, yet the effects of these agents on mammalian embryonic myocardium are largely unknown. To address this issue, we compared the chronotrophic effects of adenosinergic, adrenergic, and muscarinic agents on cultured murine embryos from postcoital day (PC) 8.0, when the fusing heart tubes first begin to beat, to PC 14, when cardiogenesis is essentially complete. At PC 8.0 and older, A(1)-adenosine receptor (A(1)AR) activation significantly decreased heart rates. Adrenergic stimulation caused modest increases in heart rates (145-155% of baseline) beginning at PC 9.0. Muscarinic activation decreased heart rates only after PC 13. When receptor gene expression was examined, A(1)ARs and beta(1)ARs were expressed in isolated hearts as early as PC 9.0, and beta(2)ARs and m(2)-muscarinic receptor genes were expressed at PC 11.0. These results identify the adenosinergic system as the earliest and most potent regulator of embryonic cardiac function and show that prenatal responsiveness to catecholamines and acetylcholine develops at later embryonic stages.

Long term follow up of the utility of troponin T to assess cardiac risk in stable chronic hemodialysis patients

Thirty long-term, stable hemodialysis patients were followed 24 months to identify any predictable relationship between elevated serum cTnT values and the diagnosis of coronary artery disease and/or the occurrence of a cardiac death. Patients with a baseline cTnT value of >0.1 microg/L were at high risk for life-threatening cardiac events during the 2 years follow-up. With regard to predicting a cardiac event, cTnT has a specificity of 93.75% and sensitivity of 81.8% compared to cTnI whose specificity was 87.5% but sensitivity of between 9.1 and 18.2%. CK-MB was the most specific at 100% but had a low sensitivity of 9.1%. The hemodialysis process, while causing an increase in the serum levels of all the markers studied except CK, the increase only proved significant for cTnT. The only markers whose stratification remained consistent over the 2 years where cTnT and CK-MB, for all others a gain or lose was registered. Baseline stratification using cTnT with a cut-off value of >0.1 microg/L offers opportunities to select at risk hemodialysis patients for corrective cardiovascular intervention.

Significance of plasma cytokine levels in melanoma patients with histologically negative sentinel lymph nodes

INTRODUCTION

Although sentinel lymph node (SLN) status is the most powerful predictor of prognosis in patients with clinically localized melanoma, a proportion of melanoma patients with histologically negative SLNs will still recur. It is hypothesized that tumor response may be altered or mediated by specific cytokines. We therefore investigated whether levels of IL-4, IL-6, IL-10, TNF-alpha, or IFN-gamma would predict disease recurrence in melanoma patients with histologically negative SLNs.

METHODS

This prospective cohort study involved 218 patients with clinically localized melanoma who underwent a histologically negative SLN biopsy. Preoperative plasma cytokine levels were determined by enzyme-linked immunosorbent assay on these patients, as well as on 90 healthy controls. Kaplan-Meier life tables were constructed, and Cox proportional hazards analyses were performed to assess predictors of disease-free survival (DFS).

RESULTS

At a median follow-up of 43 months, 33 of 218 patients (15%) had suffered disease recurrence. Melanoma patients had significant elevations of IL-4, IL-6, and IL-10 compared to healthy controls; levels of IFN-gamma were less elevated in melanoma patients compared to controls. Despite this, melanoma patients with detectable IFN-gamma levels were at significantly higher risk for recurrence compared to patients with undetectable levels (5-year DFS 70% vs. 86%, P = .03). On multivariate analysis including standard melanoma prognostic factors, only tumor thickness (P = .004) and the presence of detectable IFN-gamma levels (P = .05) were significant independent prognostic factors for disease-free survival.

CONCLUSIONS

Among melanoma patients with clinically localized disease who have undergone a histologically negative SLN biopsy, presence of a detectable plasma level of IFN-gamma is an independent predictor of disease recurrence. Elevated levels of IFN-gamma may identify a group of early-stage melanoma patients who are more likely to have recurrence of disease and who may benefit from adjuvant therapies, including immunotherapies.

Limitations of size as a criterion in the evaluation of adrenal tumors

BACKGROUND

Size has been considered to be the single best predictor of malignancy in adrenal neoplasms that have been identified incidentally. However, small adrenal cortical cancers have been reported from multiple centers.

METHODS

We retrospectively evaluated the value of tumor size and other clinical parameters in the prediction of the presence of adrenal malignancy.

RESULTS

The records of 117 patients who underwent evaluation for tumors of the adrenal gland were reviewed. The median tumor size of the adrenal cortical carcinomas (n = 38 carcinomas) was 9.2 cm (range, 1.7-30 cm); 5 cancers (13.5%) were smaller than 5.0 cm. The median overall size of the benign tumors, excluding pheochromocytomas, was 4.0 cm (n = 38 carcinomas); 10 benign tumors (26%) were larger than 5.0 cm. The imaging features of 4 of 5 small adrenal cancers predicted malignancy; the remaining patients had hormonally functioning tumors. The imaging features of 7 of 10 large benign adrenal tumors predicted benign histologic features, including 5 of 5 myelolipomas.

CONCLUSIONS

Although size remains a good predictor of the histologic features and clinical behavior of adrenal neoplasms, both small adrenal cortical cancers and large benign tumors occur with measurable frequency. High-quality imaging studies may be helpful in the identification of relatively small adrenal cancers and of characteristic benign lesions that may be selectively followed.

How many lymph nodes are enough during sentinel lymphadenectomy for primary melanoma?

BACKGROUND

Sentinel lymph node (SLN) biopsy has been shown to reliably identify nodal metastases and the subsequent need for further surgical and adjuvant therapy in patients with cutaneous melanoma. Although SLN identification rates have improved with the addition of radioactive colloid to the blue dye technique, it remains unclear how many lymph nodes should be removed to accurately determine the histologic status of the nodal basin. The objective of this study was to determine the optimal extent of SLN biopsy in these patients.

METHODS

The records of 633 consecutive patients with melanoma (765 nodal basins) whose primary treatment included SLN biopsy with the use of a combination of blue dye and technetium Tc 99 labeled sulfur colloid were reviewed. SLN biopsy consisted of the removal of all of the blue-stained nodes and all nodes with radiotracer uptake activity of at least twice background.

RESULTS

SLN biopsy was successful in 765 of 772 basins (99%). A mean of 1.9 SLNs (median, 2 SLNs) per basin were excised. At least 3 SLNs were removed in 176 basins (23%). The overall histologic status of a basin was always established by the first or second SLN harvested (ie, in no patient was the third or subsequent SLN positive when 1 of the first 2 was not). Of the 124 basins containing lymphatic metastases, the SLN that contained the maximal radiotracer uptake (hottest) and/or stained blue was pathologically positive in 118 basins (95%). In only 6 of the 124 positive basins (5%) was the sole evidence of occult nodal metastases identified in an SLN that was neither blue-stained nor the hottest. All but 1 of these SLNs had counts that were at least 66% of the hottest node in the basin.

CONCLUSIONS

With a combined modality approach to SLN biopsy, removal of more than 2 SLNs did not provide information that upstaged any patient with primary melanoma. Removal of additional nonblue SLN(s) that contained radioactive counts of at least twice background but lower than two thirds of the SLNs with maximal radiotracer uptake affected patient management in less than 0.2% of all cases. These findings may be helpful in minimizing the extent of surgery and perhaps in reducing the costs and resource use associated with operating room time and pathologic examination.

Cost and utilization impact of a clinical pathway for patients undergoing pancreaticoduodenectomy

BACKGROUND

When implemented in several common surgical procedures, clinical pathways have been reported to reduce costs and resource utilization, while maintaining or improving patient care. However, there is little data to support their use in more complex surgery. The objective of this study was to determine the effects of clinical pathway implementation in patients undergoing elective pancreaticoduodenectomy (PD) on cost and resource utilization.

METHODS

Outcome data from before and after the development of a clinical pathway were analyzed. The clinical pathway standardized the preoperative outpatient care, critical care, and postoperative floor care of patients who underwent PD. An independent department determined total costs for each patient, which included all hospital and physician costs, in a blinded review. Outcomes that were examined included perioperative mortality, postoperative morbidity, length of stay, readmissions, and postoperative clinic visits.

RESULTS

From January, 1996 to December, 1998, 148 consecutive patients underwent PD or total pancreatectomy; 68 before pathway development (PrePath) and 80 after pathway implementation (PostPath). There were no significant differences in patient demographics, comorbid conditions, underlying diagnosis, or use of neoadjuvant therapy between the two groups. Mean total costs were significantly reduced in PostPath patients compared with PrePath patients ($36,627 vs. $47,515; P = .003). Similarly, mean length of hospital stay was also significantly reduced in PostPath patients (13.5 vs. 16.4 days; P = .001). The total cost differences could not be attributed solely to differences in room and board costs. Cost and length-of-stay differences remained when outliers were excluded from the analysis. Despite these findings, there were no significant differences between PrePath and PostPath patients in terms of perioperative mortality (3% vs. 1%), readmissions within 1 month of discharge (15% vs. 11%), or mean number of clinic visits within 90 days of discharge (3.3 vs. 3.4 visits).

CONCLUSIONS

The establishment of a clinical pathway for PD patients dramatically reduced costs and resource utilization without any apparent detrimental effect on quality of patient care. These findings support the implementation of clinical pathways for PD patients, as well as investigation into pathway care for other complex surgical procedures.

Two populations of beta-spectrin in rat skeletal muscle

We use immunoblotting, immunoprecipitation, and centrifugation in sucrose density gradients to show that the product of the erythrocyte beta-spectrin gene in rat skeletal muscle (muscle beta-spectrin) is present in two states, one associated with fodrin, and another that is not associated with any identifiable spectrin or fodrin subunit. Immunofluorescence studies indicate that a significant amount of beta-spectrin without alpha-fodrin is present in the myoplasm of some muscle fibers, and, more strikingly, at distinct regions of the sarcolemma. These results suggest that alpha-fodrin and muscle beta-spectrin associate in muscle in situ, but that some muscle beta-spectrin without a paired alpha-subunit forms distinct domains at the sarcolemma.

Outcomes research in surgical oncology

BACKGROUND

There have been significant developments and advances in the area of outcomes research in the past 25 years. Unfortunately, many surgical oncologists may not have a clear concept of outcomes research and the methodology involved.

METHODS

A literature-based review article was done that included an overview of outcomes research, and study design and types, outcome measures, outcome instruments, and sources of outcome data were examined. In addition, we reviewed small area variation/volume outcome analysis as well as quality-of-life studies and their applications in surgical oncology clinical investigation. Specific examples from surgical oncology were identified.

RESULTS

As the costs of health care have increased, so has the emphasis on measuring outcomes of medical and surgical care to determine the quality and appropriateness of care. Marked variations in a variety of outcomes after oncological procedures have been attributed to individual surgeon and institution characteristics. Because much of the clinical surgical oncology literature deals only with the traditional mortality and morbidity outcomes, a more comprehensive examination of patient outcomes is required to fully evaluate the impact of patient management decisions. Health-related quality of life can be measured and analyzed in several ways and decisions regarding the use of such methodology are dependent on multiple factors.

CONCLUSIONS

Surgical oncologists should recognize that the true value of their interventions requires systematic and comprehensive examination of patient outcomes.

Significance of multiple nodal basin drainage in truncal melanoma patients undergoing sentinel lymph node biopsy

BACKGROUND

Although previous studies have demonstrated that truncal site is associated with an adverse prognosis, explanations for such risk are lacking. In addition, the number of nodal basins as well as the number of lymph nodes containing regional metastases are important prognostic factors in these patients. Because the lymphatic drainage pattern of truncal melanoma often includes more than one basin, we designed a study to evaluate (1) whether patients with multiple nodal basin drainage (MNBD) were at an increased risk of lymph node metastases identified by sentinel lymph node (SLN) biopsy, and (2) whether the histological status of an individual basin reliably predicted the status of the other draining basins in patients with MNBD.

METHODS

The records of 295 consecutive truncal melanoma patients who were managed primarily with intraoperative lymphatic mapping and SLN biopsy, between 1991 and 1997, were reviewed. All patients underwent preoperative lymphoscintigraphy, which established the number and location of draining nodal basins. Univariate and multivariate analyses of relevant clinicopathological factors were performed to assess which factors may predict the presence of a pathologically positive SLN.

RESULTS

At least one SLN was identified in 281 patients. MNBD was present in 86 (31%) patients, and a pathologically positive SLN was found in 56 (20%) patients. By multivariate analysis, the presence of MNBD (relative risk = 1.9; P = .03), tumor thickness (P = .007), and tumor ulceration (relative risk = 2.4; P = .01) were significant independent risk factors for the presence of at least one pathologically positive SLN. SLN pathology in one basin did not predict the histology of other basins in 19 (22%) of 86 patients with MNBD.

CONCLUSIONS

MNBD is independently associated with an increased risk of nodal metastases in truncal melanoma patients. Because the histological status of an individual basin did not reliably predict the status of the other draining basins in patients with MNBD, it is important to adequately identify and completely assess all nodal basins at risk, as defined by lymphoscintigraphy, in truncal melanoma patients.

Laparoscopic splenectomy in patients with hematologic malignancies

BACKGROUND

Although laparoscopic splenectomy (LS) for benign hematologic disease is well accepted, its role in hematologic malignancies is not clearly defined. This study examined the efficacy and feasibility of LS for hematologic malignancies.

METHODS

Records were reviewed from patients who underwent LS at two university hospitals. Charts from 77 open splenectomies for malignancy (OM) during the same period were also reviewed.

RESULTS

Fifty-three patients underwent LS, 22 for hematologic malignancies (LM) and 31 for benign hematologic disorders (LB). Median splenic weight was greater in the LM group (930 g) than in the LB group (164 g, P = 0.001). LM was associated with longer operations and greater blood loss than was LB. LM had a 41% conversion rate. Morbidity, mortality, and transfusion rates were similar. Median hospital stay was shorter for LM (4 days) than for OM (6 days, P = 0.001).

CONCLUSIONS

LS is feasible in hematologic malignancies but is associated with increased operative time and blood loss and a high conversion rate. Morbidity and mortality, however, was similar. Shorter hospital stays for LM compared with OM may translate into earlier recovery and initiation of antineoplastic therapy.

Using urinary biomarkers to evaluate renal effects of a Cox-2 NSAID in volunteers

We explored urinary biomarkers as an alternative for measuring the effect of an experimental COX-2 inhibitor on renal function in volunteers. Thirty male volunteers between the ages of 20-40 were enrolled and a COX-2 NSAID was given in a blinded design. The acute administration of an oral COX-2 NSAID resulted in a consistent increase in the urinary enzyme AAP at 2 hours. At 24 hours after COX-2 NSAID administration values for most of the urinary biomarkers had returned to baseline suggesting that such effects are transient and without clinical significance in situations of acute administration.

Urinary biomarkers: recommendations of the Joint European/United States Workshop for future research

The session concluded on a positive note with enthusiasm on the part of participates to become involved in one of the proposed joint protocols. Left to be answered was whether or not individual urinary biomarkers can be tailored to be disease specific or will there always be a need for a panel of biomarkers to insure interpretable results? It was agreed that proposals for three studies would be prepared. The first study will take advantage of the fact that field studies are currently being organized by both European and American groups. European scientists are working with the World Health Organization to investigate lead exposure in a region of China. At the same time, scientists in the United States are implementing a surveillance program in a population exposed to lead and other heavy metals in Kellogg, Idaho. These efforts provide an excellent opportunity for the sharing of samples and the study of a biomarkers panel that would contain both standard and candidate biomarkers. It was agreed that the parties interested in participating would alert the workshop organizers. The second study will expand upon a protocol developed by Dr. Debroe that has as its subjects non-transplant patients being treated with cyclosporine. An additional complimentary study of tacrolimus (FK-506) nephrotoxicity will also be developed. This protocol will be designed to follow the loss of renal function with a urinary biomarkers panel. The third study will follow the lead of Dr. Safirstein who urged the consideration of Cisplatin nephrotoxicity as a singular model for analyzing the usefulness of various biomarkers as measures of both acute and chronic nephrotoxicity.

An animal model of chronic cyclosporine nephrotoxicity

The development of a reproducible animal model that mimics CSA nephropathy in man has allowed the examination of the several proposed mechanisms of toxicity. While the precise mechanism remains to be defined, important clues have been provided and creative techniques for minimizing the adverse effects of this very valuable adjunct to transplant success have been identified.

Troponin T, a predictor of death in chronic haemodialysis patients

Of the 10 chronic haemodialysis patients whose serum TnT levels exceeded the threshold value of 0.1 microg.L(-1) at entry into the study, four were dead at 1 year and three others had a diagnosis of CAD. Of the 20 chronic haemodialysis patients with normal serum TnT levels at entry, one died and none had CAD. All five deaths were cardiac related, either arising from acute myocardial infarction or by sudden death. When serum TnT levels were compared with accepted predictors of death in chronic haemodialysis patients, such as serum creatinine, serum albumin and haematocrit, in the present study serum TnT proved to be more accurate and had excellent sensitivity and specificity. Serum TnT was also superior to serum TnI, which proved to be no more discriminating than the non-specific muscle marker, aldolase.

First Report of White Mold (Sclerotinia sclerotiorum) on Soybean in Maine

White mold or Sclerotinia stem rot (Sclerotinia sclerotiorum (Lib) de-Bary) was first observed on soybean varieties in a variety trial at the Maine Agricultural and Forest Experiment Station, Presque Isle, and in commercial soybean fields in late July and August 1997. Symptoms and signs included stem bleaching, fluffy white mycelial growth on soybean stems and foliage, and presence of sclerotia typical of white mold. Disease assessment, based on symptoms, was conducted on the varieties in the trial in the experiment station. Field observations on disease occurrence were also conducted in commercial soybean fields in northern Maine. In the variety trial experiment, mean incidence (%) of white mold ranged from 0 to 6.8% on Lambert, APK007, P9092, P9132, and Stine varieties. No white mold was detected on P9071, P9007, Korada, Bravor, Ugo, APK020, and Aquillon varieties. Of the infected varieties, incidence of white mold was detected in 10 of 33 fields examined. This is the first report of the occurrence of white mold on soybean in Maine. Because of large-scale commercial potato production in the region, and previous occurrence of white mold on potato, it is likely that the pathogen is present in soils of various commercial potato fields in Maine. Precautions should, therefore, be taken in introducing resistant varieties and ensuring proper rotation and cropping sequences as soybean production increases in Maine.

Analgesic nephropathy and the use of nonsteroidal anti-inflammatory drugs in renal patients: new insight

Analgesic-associated nephropathy due to analgesic mixtures and possibly due to nonsteroidal anti-inflammatory drugs taken over long periods of time represent a preventable cause of chronic renal failure. The exact prevalence of this condition in various countries around the world is still unclear almost 30 years after the original description of this entity. With the advent of specific diagnostic criteria, the prevalence should become much more clear by studying dialysis populations and other patients with chronic renal disease prior to end stage. The effect of analgesics and nonsteroidal drugs on renal disease of other established etiologies is not well-characterized either. Just as blood pressure control is essential in prolonging the course of chronic renal failure, the use of these NSAIDs may be a risk factor for accelerating such clinical courses. It is of interest that recent preliminary epidemiologic data suggest that prolonged and heavy use of illicit drugs can also be a risk factor for chronic renal disease (personal communication). Such risk factors are compatible with a public health approach towards prevention of a disease state in which expensive resources are necessary and for which the affected population is growing at alarming rates worldwide. Pharmaceutical manufacturers should be required to conduct properly controlled safety studies for long-term effects of compounds, particularly when they are to be released for over-the-counter consumption and are to be heavily marketed.

Surgeon-related factors and outcome in rectal cancer

OBJECTIVE

To determine whether surgical subspecialty training in colorectal surgery or frequency of rectal cancer resection by the surgeon are independent prognostic factors for local recurrence (LR) and survival.

SUMMARY BACKGROUND DATA

Variation in patient outcome in rectal cancer has been shown among centers and among individual surgeons. However, the prognostic importance of surgeon-related factors is largely unknown.

METHODS

All patients undergoing potentially curative low anterior resection or abdominoperineal resection for primary adenocarcinoma of the rectum between 1983 and 1990 at the five Edmonton general hospitals were reviewed in a historic-prospective study design. Preoperative, intraoperative, pathologic, adjuvant therapy, and outcome variables were obtained. Outcomes of interest included LR and disease-specific survival (DSS). To determine survival rates and to control both confounding and interaction, multivariate analysis was performed using Cox proportional hazards regression.

RESULTS

The study included 683 patients involving 52 surgeons, with > 5-year follow-up obtained on 663 (97%) patients. There were five colorectal-trained surgeons who performed 109 (16%) of the operations. Independent of surgeon training, 323 operations (47%) were done by surgeons performing < 21 rectal cancer resections over the study period. Multivariate analysis showed that the risk of LR was increased in patients of both noncolorectal trained surgeons (hazard ratio (HR) = 2.5, p = 0.001) and those of surgeons performing < 21 resections (HR = 1.8, p < 0.001). Stage (p < 0.001), use of adjuvant therapy (p = 0.002), rectal perforation or tumor spill (p < 0.001), and vascular/neural invasion (p = 0.002) also were significant prognostic factors for LR. Similarly, decreased disease-specific survival was found to be independently associated with noncolorectal-trained surgeons (HR = 1.5, p = 0.03) and surgeons performing < 21 resections (HR = 1.4, p = 0.005). Stage (p < 0.001), grade (p = 0.02), age (p = 0.02), rectal perforation or tumor spill (p < 0.001), and vascular or neural invasion (p < 0.001) were other significant prognostic factors for DSS.

CONCLUSION

Outcome is improved with both colorectal surgical subspecialty training and a higher frequency of rectal cancer surgery. Therefore, the surgical treatment of rectal cancer patients should rely exclusively on surgeons with such training or surgeons with more experience.

Inadvertent perforation of the rectum during abdominoperineal resection

BACKGROUND

Intraoperative inadvertent perforation of the rectum is a potentially avoidable complication of abdominoperineal resection (APR). Although widely thought to be detrimental, the impact of inadvertent perforation on outcome has not been conclusively determined, especially after controlling for potential confounding variables. The objective of this study was to determine if inadvertent perforation of the rectum during APR for rectal cancer is an independent risk factor for the adverse outcomes of local recurrence and/or death.

METHODS

This retrospective cohort study included all patients who underwent APR for primary adenocarcinoma of the rectum at a single teaching hospital from 1980 to 1990. Data were obtained regarding patient demographics, presence of inadvertent perforation, histopathological characteristics, adjuvant therapy, local recurrence, and survival.

RESULTS

Of 178 patients included in the study, 42 (24%) had inadvertent perforation. By univariate analysis, local recurrence was significantly higher in the perforated group than the nonperforated group (54% vs 17%; P < 0.001). Similarly, 5-year survival was significantly decreased with inadvertent perforation (29% vs 59%; P = 0.003). Multivariate analysis controlling for stage, grade, age, sex, and adjuvant therapy showed inadvertent perforation to be an independent risk factor for both increased local recurrence and decreased 5-year survival (Hazard Ratio for each model).

CONCLUSIONS

Inadvertent perforation of the rectum during APR is associated with increased local recurrence and decreased 5-year survival. The detrimental implications of inadvertent perforation during APR mandates meticulous avoidance.

Acetaminophen/aspirin mixtures: experimental data

The pertinent literature concerning the experimental induction of analgesic nephropathy is reviewed. Based on the accumulated data from animal experiments that induced a pathologic lesion resembling chronic analgesic nephropathy, of the limited number of analgesics tested, aspirin seems to be the most nephrotoxic of the commonly available analgesics. When aspirin is combined with other analgesics, the limited data available suggest at least an additive nephrotoxic effect, if not a synergism. The histologic presentation of acute intoxication is substantially different from that following chronic ingestion. With improvements in pathologic analysis of experimental results, future studies may well provide more insight as to the significance, relative contribution, and risk of combination analgesic products in inducing experimental analgesic nephrotoxicity.

The ultimate modification in the modified neck dissection

PURPOSE

A study was undertaken to study the potential benefits for function and regional recurrence of preserving the sensory ventral branches of the cervical plexus in modified neck dissections.

METHODS

Fifteen cases of squamous cell carcinoma or melanoma of the head and neck in which the sensory nerves were spared were matched to 15 cases in which the nerves were sacrificed. The subjects were examined for sensory loss, questioned regarding acute and chronic dysfunction, and followed for regional recurrence for a minimum of 2 years.

RESULTS

The group whose nerves were preserved had significantly less sensory loss and a lower incidence of acute and chronic dysfunction. No subjects in either group had regional recurrence.

CONCLUSION

The results of this initial study support a policy of routine preservation of the sensory ventral branches of the cervical plexus when there is no direct tumor involvement.

Assessing the outcome of rehabilitation in patients with end-stage renal disease

Assessing the rehabilitative/restorative process requires the definition of desired outcome. Traditionally, medicine has defined the desired outcome of treatment as curing disease. End-stage renal disease (ESRD) cannot be cured by applying current biotechnology. Thus, to assess treatment interventions in patients with ESRD, the desired outcome must be expanded to incorporate the broader components of health, which include physical, mental, and social well-being or quality of life. Based on this expanded definition of health, desirable treatment outcomes in patients with ESRD include employment of those able to work, individual control over the effects of kidney disease and dialysis, enhanced fitness, improved communications with caregivers and family, improved compliance with the dialysis regimen, and resumption of many activities enjoyed before the initiation of dialysis. Broadening the definition of desired outcome requires new measurement techniques. Measurement instruments for health status must evaluate fixed disease, which imposes certain limits on expected outcome; mutable health status, which represents the focus of intervention; and factors unrelated to healthcare, which will modify the scope of intervention that can be prescribed. Health-care status involves both self-reported evaluation and physical assessment. The reporting forms should be comprehensive, convenient, controlled, and valid. Such forms can be targeted to gain information about the natural evolution of a disease or disability process, to evaluate the effectiveness of treatment or other intervention on altering the disease or disability outcome, and to measure the quality of care. Two examples of the application of health status assessment will be reviewed.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of contrast agents on renal function

RATIONALE AND OBJECTIVES

Contrast-induced changes produced in normal renal function are discussed, and possible mechanisms by which such changes may occur are described. Animal experiments are reviewed, with the dog model providing results most closely approximating observations in humans.

METHODS

In the previous studies considered, standard clearance techniques were used to assess glomerulo-vascular changes, while urinary enzyme and protein excretions, along with changes in tubular reabsorption of electrolytes, were examined as indirect measures of contrast-induced tubular effects. The selection of papers for review was based primarily on studies conducted in large animals and humans. To be incorporated, traditional studies regarding accepted methods of analyzing renal function that did not involve extensive surgical preparation were reviewed.

RESULTS

Renal vascular effects of contrast media induce a biphasic change in renal blood flow--a brief increase followed by a more prolonged decline--the magnitude of which varies by dose and route of administration. Tubular effects include increased excretion of cytosolic enzymes plus changes in tubular reabsorption of sodium, potassium, and chloride. A transient osmotic diuresis also occurs.

CONCLUSIONS

Changes in renal blood flow, glomerular filtration rate, urinary electrolyte and solute excretion, and modification of the urinary concentrating-diluting mechanisms have yielded insights into the tubulo-glomerular actions of contrast media. The link between acute renal effects and subsequent contrast-associated nephropathy, while not absolutely defined, is becoming better understood as new information is gained using experimental models that more closely approximate high-risk states, including states of volume depletion, circulatory insufficiency, and pre-existing renal damage. Current attention is focused on the tubulo-glomerular feedback mechanism as accounting for the renal effects of contrast media.

Contrast medium-associated nephropathy. Recognition and management

The single most important risk factor for the development of CAN is significant renal insufficiency, which correlates with a stable sCr greater than 1.5 mg/dL. Based on the outcome data summarized, avoidance of CAN should be our goal, as it causes significant deterioration of renal function in one of every four patients afflicted. Clearly, volume depletion should be eliminated before administering radiographic CM. In addition, high-risk patients should have a hydration protocol initiated before the procedure and continued for at least 2 hours postprocedure. At least one large cooperative study has reported a significant reduction in CAN when LOICM was compared with HOICM. Limiting the total volume of radiographic CM used for an individual study also seems to reduce the incidence of CAN. Although indications for invasive studies with radiographic RCM continue to expand, especially for elderly and other high-risk groups, using these suggestions as guidelines should minimize the risk of CAN while still obtaining the critical information needed to develop a clinical management plan.