Overcoming Barriers to Tumor Genomic Profiling through Direct-to-Patient Outreach

PURPOSE

To overcome barriers to genomic testing for patients with rare cancers, we initiated a program to offer free clinical tumor genomic testing worldwide to patients with select rare cancer subtypes.

EXPERIMENTAL DESIGN

Patients were recruited through social media outreach and engagement with disease-specific advocacy groups, with a focus on patients with histiocytosis, germ cell tumors (GCT), and pediatric cancers. Tumors were analyzed using the MSK-IMPACT next-generation sequencing assay with the return of results to patients and their local physicians. Whole-exome recapture was performed for female patients with GCTs to define the genomic landscape of this rare cancer subtype.

RESULTS

A total of 333 patients were enrolled, and tumor tissue was received for 288 (86.4%), with 250 (86.8%) having tumor DNA of sufficient quality for MSK-IMPACT testing. Eighteen patients with histiocytosis have received genomically guided therapy to date, of whom 17 (94%) have had clinical benefit with a mean treatment duration of 21.7 months (range, 6-40+). Whole-exome sequencing of ovarian GCTs identified a subset with haploid genotypes, a phenotype rarely observed in other cancer types. Actionable genomic alterations were rare in ovarian GCT (28%); however, 2 patients with ovarian GCTs with squamous transformation had high tumor mutational burden, one of whom had a complete response to pembrolizumab.

CONCLUSIONS

Direct-to-patient outreach can facilitate the assembly of cohorts of rare cancers of sufficient size to define their genomic landscape. By profiling tumors in a clinical laboratory, results could be reported to patients and their local physicians to guide treatment. See related commentary by Desai and Subbiah, p. 2339.

S100A7: from mechanism to cancer therapy

Within the tumor, malignant and stromal cells support each other by secreting a wide variety of growth factors and cytokines, allowing tumor growth and disease progression. The identification and regulation of those key factors in this crosstalk has opened the opportunity to develop new therapeutic strategies that not only act on the tumor cells but also on the stroma. Among these factors, S100A7 protein has gained interest in the last years. With key roles in cell motility its expression correlates with increased tumor growth, angiogenesis and metastatic potential. This work aims to deepen in the role played by extracellular S100A7 in the tumor microenvironment, offering a new integrative insight of its mechanism of action on each cellular compartment (tumor, endothelial, immune and fibroblast). As a result, we demonstrate its implication in cell migration and invasion, and its important contribution to the formation of a proinflammatory and proangiogenic environment that favors tumor progression and metastasis. Furthermore, we define its possible role in the pre-metastatic niche formation. Considering the relevance of S100A7 in cancer progression, we have developed neutralizing monoclonal antibodies, reporting for the first time the proof of principle of this promising therapeutic strategy for cancer treatment.

TNF-related apoptosis-inducing ligand and cardiovascular disease in rheumatoid arthritis

OBJECTIVES

We examined the association of TNF-related apoptosis-inducing ligand (TRAIL) concentrations with cardiovascular disease (CVD) in rheumatoid arthritis (RA) and, since osteoprotegerin (OPG) can act as a decoy receptor for TRAIL, whether TRAIL concentrations impact on the OPG level-atherosclerotic CVD relation that was recently documented in the present cohort.

METHODS

TRAIL concentrations were assessed by ELISA in 151 RA patients of which 75 (49.7%) had CVD comprising ischaemic heart disease (n=27), cerebrovascular accident (n=26), peripheral artery disease (n=9) or/and heart failure (HF) (n=27), and 62 controls.

RESULTS

Mean RA duration was 12 years. In RA patients, C-reactive protein (CRP) levels and cholesterol-HDL cholesterol ratio related to TRAIL concentrations [partial R=-0.222 (p=0.006) and 0.174 (p=0.04), respectively]. TRAIL concentrations were smaller in RA patients compared to controls (median (interquartile range) = 80.2 (60.9-120.4) versus 130.4 (89.4-167.7) pg/ml, p<0.0001)). TRAIL levels were larger in RA patients with compared to those without HF (105.5 (66.5-143.4) versus 79.9 (57.8-110.6), p=0.02); this difference was independent of demographic characteristics and traditional cardiovascular risk factors (p=0.04) but not CRP concentrations (p=0.1). TRAIL levels were consistently unrelated to atherosclerotic CVD. Our previously reported OPG-atherosclerotic CVD relation in RA survived adjustment for TRAIL concentrations in a mixed regression model (p=0.04).

CONCLUSIONS

TRAIL concentrations are markedly reduced and associated with HF in established RA, this relationship being explained by CRP levels. OPG may directly enhance CVD risk in RA.

Genome-wide association study for radiographic vertebral fractures: a potential role for the 16q24 BMD locus

Vertebral fracture risk is a heritable complex trait. The aim of this study was to identify genetic susceptibility factors for osteoporotic vertebral fractures applying a genome-wide association study (GWAS) approach. The GWAS discovery was based on the Rotterdam Study, a population-based study of elderly Dutch individuals aged > 55 years; and comprising 329 cases and 2666 controls with radiographic scoring (McCloskey–Kanis) and genetic data. Replication of one top-associated SNP was pursued by de-novo genotyping of 15 independent studies across Europe, the United States, and Australia and one Asian study. Radiographic vertebral fracture assessment was performed using McCloskey–Kanis or Genant semi-quantitative definitions. SNPs were analyzed in relation to vertebral fracture using logistic regression models corrected for age and sex. Fixed effects inverse variance and Han–Eskin alternative random effects meta-analyses were applied. Genome-wide significance was set at p < 5 × 10− 8. In the discovery, a SNP (rs11645938) on chromosome 16q24 was associated with the risk for vertebral fractures at p = 4.6 × 10− 8. However, the association was not significant across 5720 cases and 21,791 controls from 14 studies. Fixed-effects meta-analysis summary estimate was 1.06 (95% CI: 0.98–1.14; p = 0.17), displaying high degree of heterogeneity (I2 = 57%; Qhet p = 0.0006). Under Han–Eskin alternative random effects model the summary effect was significant (p = 0.0005). The SNP maps to a region previously found associated with lumbar spine bone mineral density (LS-BMD) in two large meta-analyses from the GEFOS consortium. A false positive association in the GWAS discovery cannot be excluded, yet, the low-powered setting of the discovery and replication settings (appropriate to identify risk effect size > 1.25) may still be consistent with an effect size < 1.10, more of the type expected in complex traits. Larger effort in studies with standardized phenotype definitions is needed to confirm or reject the involvement of this locus on the risk for vertebral fractures.

Adiposity, estradiol, and genetic variants of steroid-metabolizing enzymes as determinants of bone mineral density

OBJECTIVES

Bone mineral density (BMD) is a complex trait resulting from the interplay of genetic and acquired factors. The objective of this study was to explore the influence of several anthropometric, lifestyle, genetic, and hormonal factors on BMD and analyze the possible differences in men and women.

METHODS

We studied 572 individuals over 50 years of age (381 postmenopausal women and 191 men). Lumbar spine and femoral neck BMD were measured by dual energy x-ray absorptiometry. The free estrogen index (FEI) was calculated as the ratio of serum estradiol to sex hormone binding globulin in 241 individuals. Three polymorphisms in the genes coding for 17-hydroxylase/liase, sulfotransferase, and 5alpha-reductase were studied in DNA isolated from blood cells.

RESULTS

Body mass index was strongly correlated to spine and femoral BMD both in women and in men (r = 0.32-0.49; P < 0.001). FEI was also independently correlated with spine BMD in both sexes (r = 0.23 and 0.34, P < 0.01), and with femoral neck in women (r = 0.30). Women with G alleles of the sulfotransferase gene tended to have higher spine BMD than those with C alleles (P = 0.025). No other genotype-related differences in BMD were found.

CONCLUSIONS

In conclusion, the results of this study point toward body weight and estradiol levels as major factors determining BMD both in women and in men. A common polymorphism of the sulfotransferase gene also appears to be associated to spine BMD in women.

High risk of bacterobilia in advanced experimental chronic fasciolosis

Fasciolosis is recognized as an important human disease. Wistar rats experimentally infected with Fasciola hepatica were examined using data obtained in the advanced chronic state of the disease (200, 300 and 400 days post-infection, dpi). Pigment stones (PS) and bile specimens were collected. The same procedure was applied in control rats. Liver tests were determined using stored serum samples. Bacteriological bile culture revealed viable bacteria (Escherichia coli, 45% of cases, Enterococcus faecalis, 45% and Klebsiella pneumoniae, 10%). The presence of bacterobilia was associated with liver serum enzymes, including aspartate aminotransferase (AST or SGOT), alanine aminotransferase (ALT or SGPT), alkaline phosphatase (AP) and total bilirubin levels. Multivariate analysis suggested an association between bacterobilia and the following factors: duration of parasitic infection and intensity of parasitic infection supported the impression that the obstruction caused by advanced chronic fasciolosis in the rat may be related to biliary sepsis. Extrapolation to human infection in fasciolosis hyperendemic areas is discussed. In conclusion, the results of the rodent model should lead to a reconsideration of treatment features in human disease, i.e. therapeutic strategies should not only include a parasitic treatment but also consider the possibility of bacterial co-infection.

Reduced priority MELD score for hepatocellular carcinoma does not adversely impact candidate survival awaiting liver transplantation

The liver organ allocation policy of the United Network for Organ Sharing (UNOS) is based on the model for end-stage liver disease (MELD). The policy provides additional priority for candidates with hepatocellular carcinoma (HCC) who are awaiting deceased donor liver transplantation (DDLT). However, this priority was reduced on February 27, 2003 to a MELD of 20 for stage T1 and of 24 for stage T2 HCC. The aim of this study was to determine the impact of reduced priority on HCC candidate survival while on the waiting list. The UNOS database was reviewed for all HCC candidates listed after February 27, 2002, The HCC candidates were grouped into two time periods: MELD 1 (listed between February 27, 2002, and February 26, 2003) and MELD 2 (listed between February 27, 2003 and February 26, 2004). For the two time periods, the national DDLT incidence rates for HCC patients were 1.44 versus 1.53 DDLT per person-year (p = NS) and the waiting times were similar for the two periods (138.0 +/- 196.8 vs. 129.0 +/- 133.8 days; p = NS). Furthermore, the 3-, 6- and 12-month candidate, patient survival and dropout rates were also similar nationally. Regional differences in rates of DDLT for HCC were observed during both MELD periods. Consequently, the reduced MELD score for stage T1 and T2 HCC candidates awaiting DDLT has not had an impact nationally either on their survival on the waiting list or on their ability to obtain a liver transplant within a reasonable time frame. However, regional variations point to the need for reform in how organs are allocated for HCC at the regional level.

Liver transplantation in the MELD era: a single-center experience

Model for Endstage Liver Disease (MELD) score has been used to allocate organs since February 2002. This policy allocates organs to candidates with regard to severity of their underlying liver disease except in the case of hepatocellular carcinoma (HCC) patients. The purpose of this study was to determine the impact of MELD on waiting times, dropout rates, and transplantation rates in all patients awaiting liver transplantation at our center. The records of all patients listed for liver transplantation between May 28, 1999, and February 27, 2004, at the Mayo Clinic, Scottsdale, Arizona, were reviewed. Candidates were grouped by two time periods as pre-MELD or post-MELD based on date of MELD implementation (February 27, 2002). The incidence of deceased donor liver transplantation (DDLT), waiting time to DDLT, dropout rate from the waiting list because of clinical deterioration or death, and survival while waiting for or after DDLT were determined for each group. Three hundred fifty-one patients were listed for liver transplantation (195 pre-MELD, 156 post-MELD) during the study period. HCC patients had an improved rate of transplantation after MELD (pre-MELD, 1.39 persons per year; post-MELD, 3.48 persons per year). In all groups, with the exception of hepatitis C virus, the transplantation rates were the same for both categories. The hepatitis C virus group also had improved transplantation rates in the post-MELD period. HCC candidates under the new allocation policy have an increased incidence of DDLT in our institution. However, this has not disadvantaged patients with non-HCC diagnoses. Thus, the new MELD-based allocation policy has benefited all candidates by allowing more timely transplants.

Ovarian remnant syndrome

OBJECTIVE

This study was undertaken to examine surgical management of patients with ovarian remnant syndrome.

STUDY DESIGN

Data were abstracted from records of patients with a history of bilateral salpingo-oophorectomy who were treated surgically at Mayo Clinic between 1985 and 2003 for pathologically confirmed residual ovarian tissue. A follow-up questionnaire was also mailed.

RESULTS

Records review identified 186 patients (mean age, 37.6 years; mean follow-up, 1.2 years). Of 180 patients with available data, 153 (85%) underwent oophorectomy by laparotomy, 13 (7%) by laparoscopy, and 14 (8%) by transvaginal approach, mostly for endometriosis (56.8%). Of 186 patients, 105 (57%) presented with pelvic masses and 89 (48%) with pelvic pain. Remnant ovarian tissue was associated with a corpus luteum in 78 (42%) and endometriosis in 54 (29%). The intraoperative complication rate was 9.6%. Of 142 patients, 12 (9%) required subsequent re-exploration (1 ovarian remnant identified).

CONCLUSION

This heavily pretreated population has modest risk of bowel, bladder, or ureteral trauma with definitive pelvic sidewall stripping and apical vaginal excision. However, subsequent recurrence is minimal (<1%). More than 90% of patients reported resolution or marked improvement of symptoms.

Corticomuscular coherence is increased in the small postural tremor of Parkinson's disease

The mechanisms and electrophysiological characteristics of the postural tremor in Parkinson's disease (PD) have not been defined. We hypothesized that PD subjects with small amplitude postural tremor would show increased corticomuscular coherence at certain frequencies compared to PD subjects without visible tremor. Four groups of participants were studied: (1) Control without postural tremor, (2) Control with small amplitude postural tremor, (3) PD without postural tremor, and (4) PD with small amplitude postural tremor. Accelerometry and electroencephalography-electromyography fast-fourier transform and corticomuscular coherence spectra were generated. Findings showed (1) elevated corticomuscular coherence centered at 12-18 Hz in PD with small amplitude postural tremor; (2) 5-12 Hz accelerometer frequency peaks that did not shift with increasing weight loads in some individuals; and (3) 5-8 Hz accelerometer peaks that shifted frequency with increasing weight loads, consistent with a peripheral-mechanical oscillator in all groups. The small amplitude postural tremor in PD arises from heterogeneous oscillator mechanisms. The discovery of increased corticomuscular coupling shows cortical involvement in the small amplitude postural tremor of PD.

Breast cancer: presentation and intervention in women with gastrointestinal metastasis and carcinomatosis

BACKGROUND

Breast cancer metastatic to the gastrointestinal tract or peritoneum is rare. We reviewed the natural history of ductal and lobular carcinoma in women with breast cancer metastatic to the gastrointestinal tract, peritoneum, or both.

METHODS

We performed a retrospective review of all patients (1985-2000) with a pathologic diagnosis of breast cancer metastatic to the gastrointestinal tract or peritoneum. Patients were categorized into three groups: those with gastrointestinal metastasis, carcinomatosis, or both.

RESULTS

Of 73 patients, 23 (32%) had gastrointestinal metastasis only, 32 (44%) had carcinomatosis only, and 18 (25%) had both. The median age at initial breast cancer diagnosis was 55 years. The mean interval between the primary diagnosis and metastatic presentation was 7 years. Sites of gastrointestinal metastases included the esophagus (8%), stomach (28%), small intestine (19%), and colon and rectum (45%). Infiltrating lobular carcinoma represented 34 (64%) of the 53 gastrointestinal metastases. The median overall survival after diagnosis was 28 months. Palliative surgical intervention in 47 patients (64%) did not affect overall survival. Some survival benefit may have accrued to select patients with gastrointestinal metastasis who underwent surgical palliation (44 vs. 9 months). Advanced age at diagnosis and gastric metastases had a negative effect on survival, whereas treatment with systemic chemotherapy or tamoxifen had a positive effect on survival.

CONCLUSIONS

Gastrointestinal metastasis occurred more often in patients with invasive lobular carcinoma. Surgical intervention did not significantly extend overall survival but may be considered in a select group of patients.

Long-term survival and disease recurrence in patients with primary squamous cell carcinoma of the vulva

OBJECTIVES

To assess time to failure and sites of failure with extended follow-up of patients with squamous cell carcinoma (SCC) of the vulva.

METHODS

A retrospective analysis of 330 patients with primary SCC of the vulva treated at Mayo Clinic between 1955 and 1990 was conducted. The main outcome measures were the rates of treatment failure. The Kaplan-Meier method and the log-rank test were used to estimate the rates of overall survival, disease-free survival, and recurrence. The Cox proportional hazards model was used to assess independent variables as prognostic factors for treatment failure.

RESULTS

All 330 patients in the cohort underwent lymphadenectomy; 113 patients (34.2%) had involvement of the inguinofemoral nodes and 88 patients (26.7%) had treatment failure. Treatment failures occurred more frequently in patients who presented with inguinal metastasis at the primary surgery and during the first 2 years of follow-up. After 2 years, both groups, with or without positive inguinal nodes, had similar treatment failure rates. Most patients with disease recurrence in the groin died within the first 2 years of follow-up. Involvement of the inguinal nodes was the main independent predictive factor for survival, disease recurrence, and metastasis.

CONCLUSIONS

Most treatment failures occurred during the 2 years after initial surgical management. However, in 35% of patients, disease reoccurred 5 years or more after diagnosis, which demonstrates the need for long-term follow-up. Complete ipsilateral or bilateral inguinofemoral lymph node dissection ensures a thorough evaluation and treatment of the groin.

Yield of repeat wireless video capsule endoscopy in patients with obscure gastrointestinal bleeding

PURPOSE

Capsule endoscopy (CE) has been shown to have a high diagnostic yield in patients with obscure gastrointestinal bleeding (OGIB). It is not known if repeating CE improves diagnostic yield or changes patient management when the initial CE is negative or nondiagnostic. The aims of this study are (1) to understand the reasons for repeat CE, (2) to determine the diagnostic yield of repeat CE, and (3) to establish if findings on repeat CE resulted in a change in patient management.

METHODS

Between August 2001 and October 2003, we performed 391 capsule studies. Of these, 24 were repeat studies in patients with OGIB. We retrospectively reviewed the charts of these 24 patients.

RESULTS

The reasons for repeat CE were: recurrent gastrointestinal bleeding (13), limited visualization on first exam due to poor prep or blood (10), complication (1) (capsule impaction at cricopharyngeus). Eighteen of 24 (75%) repeat capsule studies revealed additional findings (7 arteriovenous malformations, 2 gastropathy, 2 erosions, 2 masses, 1 ulcer, 2 red spots, 1 linear streak, 1 erythema). These findings led to changes in patient management in 15 of the 24 (62.5%) cases.

CONCLUSIONS

Indications for repeat CE most commonly include recurrent gastrointestinal bleeding and limited visualization on initial study. Repeat CE results in a high yield of new findings that lead to changes in patient management. Repeat CE should be considered in patients with persistent OGIB when the initial study is negative or inconclusive.

Longitudinal changes in cognition and behavior in asymptomatic carriers of the APOE e4 allele

OBJECTIVE

To determine whether memory loss is detectable before the symptomatic presentation of mild cognitive impairment (MCI) in those at greater genetic risk for Alzheimer disease (AD) based upon presence or absence of the e4 allele of APOE.

METHODS

Participants were age 50 years or older who responded to newspaper advertisements. A total of 212 cognitively normal individuals of known APOE genotype were initially enrolled in a match paradigm that included e4 homozygotes, e3/4 heterozygotes, and e4 noncarriers in a 1:1:2 ratio (53 sets). Of the original 212 individually matched participants, 180 completed at least two epochs of testing including 45 APOE e4/4 homozygotes, 42 APOE e3/4 heterozygotes, and 93 APOE e4 noncarriers, mean age 60 (+/-6.2) years. Of these, four developed MCI or AD during the follow-up period and were excluded from analysis. Longitudinal neuropsychological study included two verbal (Auditory Verbal Learning Test [AVLT], Selective Reminding Test [SRT]) and two visual (Complex Figure Test [CFT], Visual Retention Test) memory tests.

RESULTS

Multiple measures on both verbal memory tests showed poorer performance over a mean interval of 33 months in e4 carriers than noncarriers: AVLT total learning, long term delayed recall; SRT free and cued recall. Among those age 50 to 59 years, AVLT long term delayed recall, SRT free and cued recall, and CFT recall declined more in APOE e4 carriers. No differences were found in the domains of language, spatial skills, or executive function.

CONCLUSIONS

Memory declined in APOE e4 carriers before the symptomatic presentation of MCI in a cohort whose mean age was 60 years over a median period of 33 months. The decline began prior to age 60.

Histologic severity of appendicitis can be predicted by computed tomography

HYPOTHESIS

A regression model based on computed tomographic (CT) findings alone can accurately predict the histologic severity of acute appendicitis in patients who have a high disease likelihood.

DESIGN

Retrospective study.

SETTING

Mayo Clinic in Scottsdale, Ariz.

PATIENTS

Consecutive sample of 105 patients (50 women and 55 men, aged 15-89 years) undergoing nonincidental appendectomy within 3 days of nonfocused abdominal CT.

INTERVENTIONS

Computed tomographic scans and histologic features were retrospectively reinterpreted. Each patient's histologic and CT findings were scored by standardized criteria. An ordinal logistic regression model was constructed with a subset of CT findings that statistically correlated best with the final histologic features. Predicted severity values were then generated from the model.

MAIN OUTCOME MEASURE

Agreement between predicted and actual histologic severity, using weighted kappa measurement.

RESULTS

Computed tomography variables used in the model were fat stranding, appendix diameter, dependent fluid, appendolithiasis, extraluminal air, and the radiologist's overall confidence score. The weighted kappa measurement of agreement between predicted and actual histologic severity was 0.75, with a 95% confidence interval between the values of 0.59 and 0.90.

CONCLUSIONS

Computed tomographic findings, when used with the regression model developed from this pilot study, can accurately predict the histologic severity of acute appendicitis in patients initially seen with a high clinical suspicion of the disease. These findings provide a platform from which to prospectively test the model.

Postpolypectomy lower gastrointestinal bleeding: potential role of aspirin

INTRODUCTION

Limited data exist on the role of aspirin in increasing the risk of clinically significant postpolypectomy bleeding (PPB), which is defined as lower gastrointestinal (GI) hemorrhage following colonoscopic polyp removal requiring transfusion, hospitalization, endoscopic intervention, angiography, or surgery.

OBJECTIVES

To determine if aspirin use prior to colonoscopy increases the risk of clinically significant PPB.

METHODS

A case-control study of patients with clinically significant PPB at Mayo Clinic Scottsdale and Rochester was performed. Information collected included age, gender, recent use of aspirin or NSAIDs (within three days of colonoscopy), polyp characteristics, and polypectomy technique. The control group consisted of patients matched for age (+/-3 yr), gender, and cardiovascular morbidity who had undergone polypectomy without any complications. The populations were compared to determine the odds ratio (OR) of PPB with aspirin use.

RESULTS

During the study period, 20,636 patients underwent colonoscopy with polypectomy at the two institutions and 101 patients presented with clinically significant PPB. Twenty patients were excluded from analysis because of prior anticoagulant use. The remaining 81 patients were matched to 81 patients who had undergone colonoscopy without complications. The two groups were comparable in terms of polyp size (97%< or = 10 mm, bleeding group; 95%< or = 10 mm, control group). Aspirin use prior to polypectomy was 40% in the bleeding group and 33% in the control group (OR 1.41; 95% C.I. 0.68 to 3.04).

CONCLUSION

Postpolypectomy bleeding is an uncommon but important complication of endoscopic polypectomy. There was no statistically relevant difference in prior aspirin use before polypectomy in the bleeding group and the matched controls.

Reduced T-cell and dendritic cell function is related to cyclooxygenase-2 overexpression and prostaglandin E2 secretion in patients with breast cancer

BACKGROUND

In several neoplastic diseases, including breast cancer, immunosuppression correlates with disease stage, progression, and outcome. Thus, thorough analysis of immune parameters in breast cancer patients may be beneficial in designing effective anticancer immune-based therapies.

METHODS

We investigated dendritic cell and T-cell function in breast cancer patients at various stages of the disease and in age-matched controls. We also evaluated cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) levels within the tumor milieu and in the circulation.

RESULTS

T cells from cancer patients showed decreased proliferation in response to CD3 antibody stimulation. Analysis of T-cell helper type 1 and 2 cytokines revealed reduced levels of interferon-gamma, tumor necrosis factor-alpha, interleukin (IL)-12, and IL-2 and increased levels of IL-10 and IL-4. Dendritic cells from these patients showed significantly reduced expression of co-stimulatory molecules (B7 and CD40) and demonstrated reduced phagocytic ability, reduced antigen presentation to T cells, and reduced ability to mature in response to lipopolysaccharide. Data revealed increased synthesis of PGE2, an immune suppressor, along with increased expression of COX-2, a key regulator of PGE2 synthesis.

CONCLUSIONS

COX-2-induced PGE2 may contribute to immunosuppression and may directly block antitumor immunity while promoting tumor growth, providing us with the rationale for using COX-2 inhibition combined with immunotherapy.

Liver transplantation for hepatocellular carcinoma: the MELD impact

The new allocation policy of the United Network of Organ Sharing (UNOS) based on the model for end-stage liver disease (MELD) gives candidates with stage T1 or stage T2 hepatocellular carcinoma (HCC) a priority MELD score beyond their degree of hepatic decompensation. The aim of this study was to determine the impact of the new allocation policy on HCC candidates before and after the institution of MELD. The UNOS database was reviewed for all HCC candidates listed between July 1999 and July 2002. The candidates were grouped by two time periods, based on the date of implementation of new allocation policy of February 27, 2002. Pre-MELD candidates were listed for deceased donor liver transplantation (DDLT) before February 27,2002, and post-MELD candidates were listed after February 27, 2002. Candidates were compared by incidence of DDLT, time to DDLT, and dropout rate from the waiting list because of clinical deterioration or death, and survival while waiting and after DDLT. Incidence rates calculated for pre-MELD and post-MELD periods were expressed in person years. During the study, 2,074 HCC candidates were listed for DDLT in the UNOS database. The DDLT incidence rate was 0.439 transplant/person years pre-MELD and 1.454 transplant/person years post-MELD (P < 0.001). The time to DDLT was 2.28 years pre-MELD and 0.69 years post-MELD (P < 0.001). The 5-month dropout rate was 16.5% pre-MELD and 8.5% post-MELD (P < 0.001). The 5-month waiting-list survival was 90.3% pre-MELD and 95.7% post-MELD (P < 0.001). The 5-month survival after DDLT was similar for both time periods. The new allocation policy has led to an increased incidence rate of DDLT in HCC candidates. Furthermore, the 5-month dropout rate has decreased significantly. In addition, 5-month survival while waiting has increased in the post-MELD period. Thus, the new MELD-based allocation policy has benefited HCC candidates.

Abnormal corticomuscular coherence is associated with the small amplitude cortical myoclonus in Parkinson's disease

Coherence is the degree of time-locked correlation between two signals as a function of frequency. The purpose of this study was to test the following hypotheses: (1) corticomuscular coherence is abnormally increased in those Parkinson's disease (PD) patients with small amplitude cortical myoclonus, and (2) corticomuscular coherence peaks around the time of the myoclonus electromyographic (EMG) discharge. We studied Parkinson's disease patients with and without myoclonus and controls. The data were digitally collected and processed off-line with EMG rectification, creation of 511-msec epochs, Fast-Fourier transform, and coherence analysis. In the 12 to 30 Hz frequency band, but not at 30 to 60 Hz or above, coherence peaks were observed in the PD subjects with myoclonus that were significantly greater than in the control subjects (P < 0.001) and in PD subjects without myoclonus (P < 0.001). The abnormal coherence values are evidence for abnormal rhythmic activity in cortical motor areas in those Parkinson's disease patients with myoclonus. In combination with previous findings on back-averaging, our results show that this myoclonus occurs when neuronal populations are driven to an extreme amount of synchronous activity with higher corticomuscular coherence values. These results have mechanistic implications for cortical dysfunction in Parkinson's disease and for cortical myoclonus in general.

Emphysematous pyometra in a dog

An 8-year-old intact female West Highland White Terrier was examined for anorexia, vomiting, abdominal distension, and mild purulent vulvar discharge. The results of physical examination, laboratory testing, and radiography are presented. Emphysematous pyometra was suspected and confirmed at surgery. Clostridium perfringens was isolated from the uterine lumen. A brief discussion of emphysematous pyometra is presented.

Coherent EEG indicators of cognitive binding during ambiguous figure tasks

We tested the hypothesis that perception of an alternative image in ambiguous figures would be manifest as high-frequency (gamma) components that become synchronized over multiple scalp sites as a "cognitive binding" process occurs. For 171 combinations of data from 19 electrodes, obtained from 17 subjects and 10 replicate stimuli, we calculated the difference in correlation between the response to first seeing an ambiguous figure and when the alternative percept for that figure became consciously realized (cognitively bound). Numerous statistically significant correlation differences occurred in all frequency bands tested with ambiguous-figure stimulation, but not in two kinds of control data (a reaction-time test to sound stimuli and a no-task, mind-wandering test). Statistically significant correlation changes were widespread, involving frontal, parietal, central, and occipital regions of both hemispheres. Correlation changes were evident at each of five frequency bands, ranging up to 62.5 Hz. Most of the statistically significant correlation changes were not between adjacent sites but between sites relatively distant, both ipsilateral and contralateral. Typically, these correlation changes occurred in more than one frequency band. These results suggest that cognitive binding is a distinct mental state that is reliably induced by ambiguous-figure perception tasks. Coherent oscillations at multiple frequencies may reflect the mechanism by which such binding occurs. Moreover, different coherent frequencies may mediate different components of the total cognitive-binding process.

Corneal endothelial permeability after implantation of angle-fitted anterior chamber lenses in myopic phakic eyes. Preliminary results

This present study aimed to evaluate the corneal endothelium after implantation of angle-fixed anterior chamber lenses in myopic phakic eyes. Twelve eyes (9 patients) with high myopia (more than-14 diopters) were implanted with ZB5M lenses (Domilens, France). The corneal endothelium was studied by fluorophotometry (endothelial transfer coefficient: kc.ca), specular microscopy and ultrasonic pachimetry. Tests were performed prior to and 3 and 6 months after the surgery. The Wilcoxon rank test was used for the statistical analysis of the data. There was a significant difference (p < 0.05) between the preoperative kc.ca (4.15 +/- 0.72 x 10(-3) min-1) and the kc.ca three months after the implantation (4.43 +/- 0.87 x 10(-3) min-1). A statistically significant difference (p < 0.01) was also found between the three and six months postoperative kc.ca (5.31 +/- 0.81 x 10(-3) min-1). There was a significant difference (p < 0.05) between the preoperative central endothelial cell density (2533 +/- 219 cells/mm2). No significant differences were found in relation to the central corneal thickness. In conclusion, three months after the implantation of ZB5M lenses to correct high myopia in phakic eyes, the corneal endothelial function was altered and continued to be so six months after the operation.

Fluorophotometry in phakic eyes with anterior chamber intraocular lens implantation to correct myopia

In this longitudinal study, we implanted 16 angle-fixated anterior chamber intra-ocular lenses in phakic eyes of 13 patients to correct high myopia. Using fluorophotometry, we discovered a statistically significant decrease (P < .01) in lens transmittance. Blood-aqueous barrier permeability tended to remain increased six months after surgery.

Albendazole in the treatment of onchocerciasis: double-blind clinical trial in Venezuela

A double-blind clinical trial was conducted in Monagas State, Venezuela to assess the tolerance and efficacy of albendazole in the therapy of Onchocerca volvulus infection. Forty-nine patients (26 treated and 23 controls) received a 10-day course of albendazole (400 mg/day) or a placebo. Consistent with the excellent tolerance observed, albendazole did not kill microfilariae. However, analysis of changes in microfilarial densities (mf/mg of skin) over one year showed that albendazole was active against O. volvulus, presumably by interfering with embryogenesis. The nature, degree, and duration of this effect remain to be determined.

Intraoperative and external radiotherapy in resected gastric cancer: updated report of a phase II trial

From September 1984 to August 1991, 48 evaluable patients with resected gastric cancer and apparent disease confined to locoregional area were treated with intraoperative electron beam boost to the celiac axis and peripancreatic nodal areas (15 Gy) and external irradiation (40 to 46 Gy in 4 to 5 weeks) including the gastric bed and upper abdominal nodal draining regions. At the time of evaluation for IORT, the disease was primary in 38 cases, recurrent but resectable in four (anastomosis), and unresectable in four (nodal). Post operative complications were reversible. Acute tolerance to the complete treatment program was acceptable. Late complications included life-threatening events: Six episodes of gastro intestinal bleeding (three of them had an arteriographic documentation of arterioenteric fistula) and nine with severe enteritis (five required reoperation). Other long-term treatment related complications were six cases of vertebral collapse. The median follow-up time for the entire group is 22 months. Locoregional recurrence/persistence of disease has been identified in five patients (three with residual and/or recurrent postsurgical tumor). Systemic tumor progression has been detected in 15 patients (11 in intra-abdominal sites). Overall actuarial survival for patients with positive or negative serosal involvement was 33% versus 56%. It is concluded that the treatment program described is able to induce a high locoregional tumor control rate (100%) when used strictly in an adjuvant setting and might control long term, a small portion of patients not amenable for curative surgery (2 out of 8 patients with confirmed residual post-surgical disease). Gastrointestinal bleeding and enteritis are findings that indicate treatment intensity at the upper limits of tissue tolerance. Assessment of long term tolerance of pancreatic parenchyma and large blood vessels (tissues included in the IRORT field) are pending for longer follow-up and the appropriate selective studies.

Arteriodigestive fistula: a complication associated with intraoperative and external beam radiotherapy following surgery for gastric cancer

Intestinal hemorrhage due to arteriodigestive fistula is described to be a rare and serious complication of radiotherapy. Three cases of this type of fistula in gastric cancer patients treated with gastrectomy, intraoperative electron boost (15 Gy), and fractionated external beam irradiation (46 Gy) are reported. Selective angiography is most helpful in the diagnosis and immediate surgery could be lifesaving. An attempt to explain the etiopathogenesis is made.

Lymphoma of the gastric stump: report of a case

We report a case of primary lymphoma on a previously resected stomach in a 62-year-old man. The patient was treated 22 years earlier with a partial gastrectomy and Billroth II reconstruction for a benign gastric ulcer. The rarity of this entity and its possible relationship with pseudolymphoma or lymphoid nodular hyperplasia is discussed, and the literature is reviewed.

Intraoperative and external beam radiotherapy in advanced resectable gastric cancer: technical description and preliminary results

Twenty-two patients with resectable gastric cancer treated with intraoperative radiotherapy and external beam irradiation, in a Phase I-II oriented study, were analyzed. Tumor Stages were III & IV in 18 cases (82%). Tumor histology was described as diffuse undifferentiated type in 14 cases (63%). Following surgical resection of the primary tumor, IORT 15 Gy was delivered in the celiac axis area, using high energy electron beams ranging from 9 to 20 MeV. External beam irradiation fields covered the draining nodal areas of the upper abdomen and the gastric bed. There were no postoperative deaths. Reversible postoperative complications were recorded in 14 patients (63%). Long term complications observed were vertebral collapse and liver hemangiomas. First sites of recurrence have been: hepatic hilum (three cases), peritoneum combined with central axis nodes (two cases), liver metastasis (one case), and lung metastasis (one case). Survival data shows a follow-up period ranging from 1+ to 33+ months, with a median survival time for the entire group of 13+ months. At the time of this report, 16 patients (72%) are still alive and six have died (four from progressive malignant disease and two from intercurrent disease). From this preliminary data, it can be concluded that a combined approach with surgical resection, intraoperative radiotherapy, and external beam irradiation is feasible in advanced gastric carcinoma, and is not limited by toxicity or any complications observed. Despite this intense loco-regional therapeutic approach, the upper abdominal failure rate has been demonstrated in 22% of the cases.

Use of the central venous pressure catheter to obtain blood cultures

The results of aerobic and anaerobic blood cultures obtained from a peripheral venopuncture and from the central venous pressure catheter were compared in critically ill patients admitted to the ICU to determine if pain and anxiety from multiple venopunctures could be alleviated while the physician's task is facilitated. The results were identical in 93.5% of the 92 comparisons. The discrepancies were evaluated and it was concluded that the method was easy, quick, and reliable. We recommend it as a suitable alternative to venopuncture.