Unplanned Hospitalization and Subsequent Mortality in Lung Cancer Patients Undergoing Concomitant Chemo-/Immuno-Therapy and Radiotherapy: An Analysis of Over 10,000 Patients in a Nationwide Database

PURPOSE/OBJECTIVE(S)

Radiotherapy (RT) and concomitant chemotherapy (CHT) is a major modality for treating many malignancies including lung cancer and is associated with toxicity-related unplanned hospitalization (UPH). Previous investigations of factors associated with UPH have been single institutional retrospective studies and none assessed the role of concurrent immunotherapy (IO). Here, we aimed to identify factors associated with UPH and in-hospital mortality by leveraging a multi-institutional nationwide database.

MATERIALS/METHODS

The Vizient® Clinical Data Base which includes data from 98% of the AAMC hospitals and 110 cancer hospitals, was queried for lung cancer patients (any histology) treated in 2019-2021 with RT+CHT/IO. Endpoints were UPH and mortality during or within 30 days of completion of RT. The variables included age, sex, race, ethnicity, income level (quartile), an education level (quartile), any concomitant CHT or IO drugs, RT technique (3D vs. IMRT vs. SBRT), obesity, prior hospitalization within 3 months, prior oncologic surgery within 3 months, prior CHT and/or IO within 3 months, insurance types, hospital types (Rural vs. Urban, AAMC vs. non-AAMC, NCCN vs. non-NCCN, bed size tertile). Logistic regression was performed to identify variables associated with UPH and in-hospital mortality. Data from the Vizient Clinical Data Base used with permission of Vizient, Inc. All rights reserved.

RESULTS

A total of 10,337 patients were included. The rate of UPH and mortality among UPH was 24.5% and 3.2%, respectively. Factors associated with UPH included other races (vs. White, OR 1.44; 95% CI 1.11-1.88; p<0.001), living in a low income zip code (OR 1.7; 95% CI 1.39-2.09; p = 0.0006), living in a zip code with lower education attainment (OR 0.71; 95% CI 0.58-0.86; p = 0.0007), CHT/IO types (cis-etoposide vs. carbo-Taxol, OR 1.33; 95% CI 1.13-1.57; p<0.0001), obesity (OR 1.71; 95% CI 1.53-1.92; p<0.0001), prior hospitalization (OR 2.0; 95% CI 1.80-2.22; p<0.0001), prior oncologic surgery (OR 0.34; 95% CI 0.22-0.52; p<0.0001), other primary payers (vs. commercial; OR 1.75; 95% CI 1.37-2.23; p<0.0001), rural hospital (OR 1.3; 95% CI 1.07-1.62, p<0.01), small bed size (OR 0.59; 95% CI 0.5-0.71; p<0.0001). Factors associated with in-hospital mortality included CHT/IO type (p<0.0001, but cis-etoposide vs. carbo-taxol no difference), prior hospitalization (OR 0.34; 95% CI 0.2-0.56; p<0.0001), AAMC (OR 2.12; 95% CI 1.23-3.67; p = 0.007), bed size (OR 0.58; 95% CI 0.38-0.88; p<0.01).

CONCLUSION

In the largest study to date regarding UPH and in-hospital mortality related to lung RT, we identified factors contributing to these endpoints. Future prospective studies are warranted to develop strategies to prevent these complications in high-risk populations.

5-Year Update of a Multi-Institution, Prospective Phase 2 Hypofractionated Postmastectomy Radiation Therapy Trial

PURPOSE

Hypofractionation in the setting of postmastectomy radiation (PMRT) is not currently the standard of care in most countries. Here we present a 5-year update of our multi-institutional, phase 2 prospective trial evaluating a novel 15-day hypofractionated PMRT regimen.

METHODS AND MATERIALS

Patients were enrolled to receive 3.33 Gy daily to the chest wall (or reconstructed breast) and regional lymphatics in 11 fractions with an optional 4-fraction mastectomy scar boost. The primary endpoint was freedom from grade 3 or higher late non-reconstruction-related radiation toxicities. Toxicities were scored using Common Terminology Criteria for Adverse Events v4.0. Secondary endpoints included local and locoregional recurrence rates, cosmesis, and reconstruction complications.

RESULTS

After enrolling 69 patients with stage II-IIIa breast cancer, 67 women were eligible for analysis. At a median follow up of 54 months, there were no acute or late grade 3 and 4 nonreconstruction reported toxicities. The grade 2 or greater late toxicity rate was only 12% and comprised grade 2 pain, fatigue, and lymphedema that persisted beyond 6 months after completion of radiation therapy. Only 3 women (4.6%) experienced a chest wall or nodal recurrence as a first site of relapse. Freedom from local failure, including local failure after distant relapse, was 92% at 5 years, and the 5-year overall survival was 90%.

CONCLUSIONS

This is the first prospective trial conducted in the United States to demonstrate the safe and effective use of hypofractionated PMRT. We have demonstrated a low complication rate while achieving excellent local control. Toxicity was better than anticipated based on previously published series of PMRT toxicities. Although our fractionation was novel, the radiobiological equivalent dose is similar to other hypofractionation schedules. This trial was the basis for the creation of Alliance A221505 (RT CHARM), which is currently accruing patients in a phase 3 randomized design.

Solar particle event storm shelter requirements for missions beyond low Earth orbit

Protecting spacecraft crews from energetic space radiations that pose both chronic and acute health risks is a critical issue for future missions beyond low Earth orbit (LEO). Chronic health risks are possible from both galactic cosmic ray and solar energetic particle event (SPE) exposures. However, SPE exposures also can pose significant short term risks including, if dose levels are high enough, acute radiation syndrome effects that can be mission- or life-threatening. In order to address the reduction of short term risks to spaceflight crews from SPEs, we have developed recommendations to NASA for a design-standard SPE to be used as the basis for evaluating the adequacy of proposed radiation shelters for cislunar missions beyond LEO. Four SPE protection requirements for habitats are proposed: (1) a blood-forming-organ limit of 250 mGy-equivalent for the design SPE; (2) a design reference SPE environment equivalent to the sum of the proton spectra during the October 1989 event series; (3) any necessary assembly of the protection system must be completed within 30 min of event onset; and (4) space protection systems must be designed to ensure that astronaut radiation exposures follow the ALARA (As Low As Reasonably Achievable) principle.

A double-blind, placebo-controlled randomized trial of creatine for the cancer anorexia/weight loss syndrome (N02C4): an Alliance trial

BACKGROUND

Multiple pilot studies, including one in colorectal cancer patients, suggest that creatine, an amino acid derivative, augments muscle, improves strength, and thereby could palliate the cancer anorexia/weight loss syndrome.

PATIENTS AND METHODS

In this randomized, double-blind, placebo-controlled trial, incurable patients with this syndrome were assigned creatine (20 g/day load×5 days followed by 2 g/day orally) versus identical placebo. Patients were weighed once a week for 1 month and then monthly. Patients were also assessed over 1 month for appetite and quality of life (validated questionnaires), fist grip strength, body composition (bioelectrical impedance), and adverse events. The primary endpoint was 10% or greater weight gain from baseline during the first month.

RESULTS

Within this combined cohort of 263 evaluable patients (134 received creatine and 129 placebo), only 3 gained ≥10% of their baseline weight by 1 month: two creatine-treated and the other placebo-exposed (P = 1.00). Questionnaire data on appetite, quality of life, and activities of daily living showed no statistically significant differences between groups. Similarly, no statistically significant differences between groups were observed for fist-grip strength or body composition. Rates and severity of adverse events were comparable between groups. Finally, a median survival of 230 and 239 days were observed in the creatine and placebo groups, respectively (P = 0.70).

CONCLUSION

Creatine, as prescribed in this trial, had no effect on the cancer anorexia/weight loss syndrome.

Physical dynamics controlling variability in nearshore fecal pollution: fecal indicator bacteria as passive particles

We present results from a 5-h field program (HB06) that took place at California's Huntington State Beach. We assessed the importance of physical dynamics in controlling fecal indicator bacteria (FIB) concentrations during HB06 using an individual based model including alongshore advection and cross-shore variable horizontal diffusion. The model was parameterized with physical (waves and currents) and bacterial (Escherichia coli and Enterococcus) observations made during HB06. The model captured surfzone FIB dynamics well (average surfzone model skill: 0.84 {E. coli} and 0.52 {Enterococcus}), but fell short of capturing offshore FIB dynamics. Our analyses support the hypothesis that surfzone FIB variability during HB06 was a consequence of southward advection and diffusion of a patch of FIB originating north of the study area. Offshore FIB may have originated from a different, southern, source. Mortality may account for some of the offshore variability not explained by the physical model.

Randomized phase II trial of panitumumab (P), erlotinib (E), and gemcitabine (G) versus erlotinib-gemcitabine in patients with untreated, metastatic pancreatic adenocarcinoma

238

Background: Dual inhibition of the EGFR pathway using erlotinib and the monoclonal antibody panitumumab results in greater antitumor activity in preclinical pancreatic cancer models. A trial evaluating this approach was conducted.

Methods: A safety analysis was initially performed with 6 patients at P 4 mg/kg every two weeks, E 100 mg daily, G 1000 mg/m2 weekly of a 28-day cycle. PGE was well tolerated with a grade 3 fatigue as only dose-limiting toxicity. Patients (pts) were then randomized to either PGE or GE alone. Eligibility included: no prior chemo, ECOG PS 0-1, bilirubin <2x UL, AST <2.5x UL. CT scans every 2 cycles.

Results: 93 pts (46-GE; 47-PGE) were randomized from January to August, 2010. Median age 61 years and 65% male. ECOG PS 0 (51%) and PS 1 (49%). No significant differences in baseline characteristics observed between treatment arms. 81 pts evaluable for AEs; 37 (46%) had a maximum grade 3 (at least possibly related to treatment), and 12 (15%) maximum grade 4 or 5. Treatment arms similar with respect to the overall AEs with exception grade 1-3 acneiform rash, GE (65%) vs. PGE (85%). Commonly occurring grade 4 AEs (at least possibly related) consisted of thrombosis (3 pts) and thrombocytopenia (2 pts). Two grade 5 events occurred in PGE arm—duodenal hemorrhage (possibly related) and pancolitis with multisystem failure (unlikely). An additional PGE pt died 30 days off study (grade 5 CHF, possibly). 54 patients (67%; 31-GE, 23-PGE) ended treatment; 38 (70%) for disease progression (24-GE; 14-PGE). Other reasons for treatment discontinuation: AEs (9; 17%), pt refusal (4; 7%), death on study (2; 4%), other (1). In 81 pts with at least 1 cycle of chemotherapy, the median PFS for GE 2.0 months and 3.3 months for PGE. Accrual for the study was recently completed and overall and 6-month survival data will be presented.

Conclusions: This study involved an initial run-in design to define tolerable doses of dual EGFR inhibitors, PGE, in pancreatic cancer patients. Although preliminary, the randomized phase II portion has been completed and differences between GE and PGE in terms of relevant clinical outcomes, PFS, are observed.

No significant financial relationships to disclose.

Simultaneous magnetically directed drug convection and MR imaging

Superparamagnetic iron oxide nanoparticles (IO NPs) are of interest for their usefulness in biomedical applications. In this work, we have synthesized iron oxide nanocomposites surface-modified with different biocompatible polymers. Bovine serum albumin (BSA) was physisorbed onto these IO NPs along with an excipient during freeze-drying. The mass transport of the protein attached to the iron oxide core-shell nanoparticles (IO cs-NPs) under a gradient magnetic field of an MRI instrument was observed in vitro and in an egg as a model system for a biological fluid. From the in vitro experiments in agarose gels, it was observed that the protein gets separated from the core during mass transport for some cs-IO, but co-migration was observed for PEG-modified IO cs-NPs. These experiments demonstrated proof-of-concept for the use of IO cs-NPs in magnetically directed drug convection.

Outcomes of conservatively managed localized prostate cancer

5010

Background: The natural history of screen-detected prostate cancer has not been well described. Methods: Cancer-specific and overall mortality, assessed through competing risk analyses, were determined for 14,516 men aged 65 years or older diagnosed between 1992–2002 and did not receive surgery or radiation within 6 months of cancer diagnosis. The population-based cohort was identified from US cancer registries, which had 98% completeness in case ascertainment. Results: Compared to earlier era studies, survival has improved considerably for conservatively managed patients diagnosed in the contemporary prostate specific antigen (PSA) era ( Table ). Conclusions: Men diagnosed with prostate cancer in the PSA era have survival outcomes significantly better than those in the past. Patients and healthcare providers may need to reassess some treatment options in light of these data.

[Table: see text]

No significant financial relationships to disclose.

Final results of NCCTG N0489: Epratuzumab and rituximab in combination with cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy (ER-CHOP) in patients with previously untreated diffuse large B-cell lymphoma

8508

Background: A prior pilot study of epratuzumab (Immunomedics) and rituximab in combination with CHOP chemotherapy (ER-CHOP) in untreated patients with diffuse large B-cell lymphoma demonstrated feasibility and safety. This multicenter NCCTG phase II study was carried out to assess efficacy. Methods: Patients received immunochemotherapy on the following schedule: epratuzumab 360 mg/m2, rituximab 375 mg/m2, and standard dose CHOP every 3 weeks for 6 cycles. Weekly blood counts were obtained to monitor hematological toxicity. Primary endpoint was 12 month event free survival (EFS12). Secondary endpoints were response rate, progression free survival, functional CR (PET negative) and toxicity. Results: 107 patients were accrued from Feb 2006 to Aug 2007. 29 patients were ineligible resulting in 78 eligible patients. Baseline patient characteristics for the eligible patients included median age 61 (range 21–82); 59% were male. 81% had advanced stage; IPI was 0–1 in 17 pts (22%), 2 in 22 pts (28%), 3 in 29 pts (37%) and 4–5 in 10 pts (13%). Based on the revised IPI (R-IPI) 50% were poor/high risk (IPI 3–5). 71% had an elevated LDH. Performance score was 0–1 in 69 pts and 2–3 in 9 pts. The ORR was 95% (CR/CRu: 73%). For the low risk IPI (0–2), ORR was 95% (CR/CRu: 74%) and for the high risk IPI (3–5), ORR was 95% (CR/CRu: 72%). The EFS at 12 months was 80%. The 12 month progression free survival (PFS12) and overall survival (OS12) is 82% and 88% respectively. EFS12, PFS12 and OS12 by IPI risk category is shown ( Table ). Conclusions: ER-CHOP every 21 days is feasible and safe. The ORR, EFS and PFS compare favorably to studies using R-CHOP especially in the high-intermediate and high risk IPI subgroups. A randomized phase III trial of R-CHOP vs ER-CHOP is needed to prove that dual antibody targeting in combination with CHOP is better.

[Table: see text]

No significant financial relationships to disclose.

Species distribution and antimicrobial resistance of enterococci isolated from surface and ocean water

AIMS

The species identification and antimicrobial resistance profiles were determined for enterococci isolated from Southern California surface and ocean waters.

METHODS AND RESULTS

Species identification was determined for 1413 presumptive Enterococcus isolates from urban runoff, bay, ocean and sewage water samples. The most frequently isolated species were Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus casseliflavus and Enterococcus mundtii. All five of these species were isolated from ocean and bay water with a frequency ranging from 7% to 36%. Enterococcus casseliflavus was the most frequently isolated species in urban runoff making up 36-65% of isolates while E. faecium was the most frequently isolated species in sewage making up 53-78% of isolates. The similar distribution of species in urban runoff and receiving water suggests that urban runoff may be the source of Enterococcus. No vancomycin or high level gentamycin resistance was detected in E. faecalis and E. faecium isolates.

CONCLUSIONS

Enterococcus faecalis, E. faecium, E. casseliflavus and E. mundtii are the most commonly isolated Enterococcus species from urban runoff and receiving waters in Southern California.

SIGNIFICANCE AND IMPACT OF THE STUDY

Determination of the Enterococcus species isolated from receiving waters and potential pollution sources may assist in determining the sources of pollution.

Stroke surveillance in Manitoba, Canada: estimates from administrative databases

This study investigated the use of population-based administrative databases for stroke surveillance. First, a meta-analysis was conducted of four studies, identified via a PubMed search, which estimated the sensitivity and specificity of hospital data for ascertaining cases of stroke when clinical registries or medical charts were the gold standard. Subsequently, case-ascertainment algorithms based on hospital, physician and prescription drug records were developed and applied to Manitoba's administrative data, and prevalence estimates were obtained for fiscal years 1995/96 to 2003/04 by age group, sex, region of residence and income quintile. The meta-analysis results revealed some over-ascertainment of stroke cases from hospital data when the algorithm was based on diagnosis codes for any type of cerebrovascular disease (Mantel-Haenszel Odds-Ratio [OR] - 1.70 [95% confidence interval (CI): 1.53 - 1.88]). Analyses of Manitoba administrative data revealed that while the total number of stroke cases varied substantially across the algorithms, the trend in prevalence was stable regardless of the algorithm adopted.

N047B: NCCTG phase II trial of vorinostat (suberoylanilide hydroxamic acid) in recurrent glioblastoma multiforme (GBM)

2004

Background: Vorinostat is a histone deacetylase inhibitor that represents a rational therapeutic target in GBM. Methods: Recurrent GBM patients (pts) having received = 1 prior chemo regimen for progressive disease were eligible. Vorinostat dose was 200 mg bid x 14 days q 3 weeks. We applied a phase II design which had 90% power to declare the regimen active if the study PFS6 rate was 25%, a 15% rate increase over PFS6 in historical controls (10%). Results: 68 patients were treated. Grade 3+ non-hematologic toxicity consisting mainly of fatigue, diarrhea and dehydration occurred in 23% of pts; Grade 3+ hematologic toxicity consisting mainly of thrombocytopenia occurred in 25% of pts. Intra-patient dose escalation to 300 mg bid resulted in higher incidence of grade 3+ thrombocytopenia (45%) and was aborted. Pts receiving enzyme-inducing anticonvulsants (EIAC) had significantly less grade 3 + non-hematologic toxicity (p=0.01) and grade 3/4 thrombocytopenia (p=0.04). Pharmacokinetic analysis showed lower vorninostat C-max and AUC (0–24h) values and higher vorinostat-glucuronide C-max and AUC (0–24h) values in EIAC pts, although this did not reach statistical significance. The trial met the prospectively defined primary efficacy endpoint at the planned interim analysis with 5 of the first 22 patients (23%) being progression-free at 6 mo. RNA array analysis, performed in paired baseline and post-vorinostat treatment samples in a separate subgroup of 5 surgical recurrent GBM pts, who received vorinostat for 6 doses prior to surgery, showed upregulation of E-cadherin (p=0.02), thus indicating a biologic effect of the HDAC inhibitor on the glioblastoma tumors. Histone acetylation, Akt, phospho-Akt, P21Waf1/Cip1 and P27Kip1 expression analysis in all patients and correlation with outcome is ongoing. Conclusions: Vorinostat is well tolerated in recurrent GBM patients. EIAC patients have less toxicity, likely due to increased vorinostat metabolism via glucuronidation. Interim efficacy analysis is indicative of antitumor activity. Final efficacy analysis, RNA array data and correlative tissue analysis will be reported.

No significant financial relationships to disclose.

A phase II study of cisplatin (P) plus etoposide (E) plus bevacizumab (B) for previously untreated extensive stage small cell lung cancer (SCLC) (E3501): A trial of the Eastern Cooperative Oncology Group

7564

Background: Scientific evidence supports the concept that the growth of solid tumors, including SCLC, is dependent on angiogenesis. Bevacizumab, a humanized monoclonal antibody against vascular endothelial growth factor (VEGF), has been shown to improve survival when combined with chemotherapy in non-small cell lung cancer. PE is a standard regimen for use in SCLC. Thus, we proposed this study of PE plus B in patients (pts) with previously untreated extensive stage SCLC. Methods: Pts with previously untreated extensive SCLC with a performance status 0–2, received P (60 mg/m2) IV followed by E (120 mg/ m2) IV followed by B (15 mg/kg) IV infusion on day 1, with E repeated on days 2 and 3 of a 21-day cycle for 4 cycles or until progressive disease (PD). Pts not experiencing PD continued bevacizumab until disease progression or unacceptable toxicity. The primary endpoint was per cent of patients alive at 6 months. Results: From 6/8/04 to 8/18/06 (includes a ten month accrual suspension to evaluate data), 64 eligible pts were accrued. Patient characteristics: median age of 65.5 years (range: 45–83), 44% males, 95% Caucasian and 9% were performance status = 2. A median of 6 cycles of treatment were administered (range: 1–12). There is toxicity data on 58 pts. The most common treatment-related grade 3 & 4 toxicities were: neutropenia (7 & 26 pts), thrombocytopenia (8 & 2 pts), fatigue (10 pts, grade 3 only), hypertension (4 pts, grade 3 only), febrile neutropenia (2 pts) and dehydration (3 pts, grade 3 only). Two pts experienced grade 5 toxicities (hypotension and infection with grade ¾ neutropenia). There were no grade ≥3 hemorrhagic events. Response information is available on 39 pts. There have been 4 complete responses and 23 partial responses for an overall response rate of 69% (90% exact CI: (55%, 81%). The proportion of pts alive and progression- free at 6 months was 33% (95% CI: 17%, 49%). Conclusions: Preliminary results indicate that the addition of B to the combination of PE in patients with previously untreated extensive stage SCLC appears promising. A randomized phase III trial comparing PE to PE + B is under consideration.

No significant financial relationships to disclose.

Myeloperoxidase predicts risk of vasculopathic events in hemizgygous males with Fabry disease

Fabry disease results in a global vasculopathy leading to early-onset stroke and renal and cardiac failure. We found that random myeloperoxidase in serum and plasma was significantly elevated in 73 consecutive male patients with Fabry disease. Random serum myeloperoxidase level in men predicted the risk of a Fabry vasculopathy-related event in subsequent years. Long-term enzyme replacement therapy did not reduce myeloperoxidase level or eliminate the risk of vasculopathic events.

Neuropathic and cerebrovascular correlates of hearing loss in Fabry disease

Fabry disease, OMIM 301500, is a progressive multisystem storage disorder due to the deficiency of alpha-galactosidase A (GALA). Neurological and vascular manifestations of this disorder with regard to hearing loss have not been analysed quantitatively in large cohorts. We conducted a retrospective cross sectional analysis of hearing loss in 109 male and female patients with Fabry disease who were referred to and seen at the Clinical Center of the National Institutes of Health, Bethesda, MD, USA on natural history and enzyme replacement study protocols. There were 85 males aged 6-58 years (mean 31 years, SD 13) and 24 females aged 22-72 years (mean 42 years, SD 12). All patients underwent a comprehensive audiological evaluation. In addition, cerebral white matter lesions, peripheral neuropathy, and kidney function were quantitatively assessed. HL(95), defined as a hearing threshold above the 95th percentile for age and gender matched normal controls, was present in 56% [95% CI (42.2-67.2)] of the males. Prevalence of HL(95) was lower in the group of patients with residual GALA enzyme activity compared with those without detectable activity (33% versus 63%) HL(95) was present in the low-, mid- and high-frequency ranges for all ages. Male patients with HL(95) had a higher microvascular cerebral white matter lesion load [1.4, interquartile range (IQR) 0-30.1 +/- versus 0, IQR 0-0], more pronounced cold perception deficit [19.4 +/- 5.5 versus 13.5 +/- 5.5 of just noticeable difference (JND) units] and lower kidney function [creatinine: 1.6 +/- 1.2 versus 0.77 +/- 0.2 mg/dl; blood urea nitrogen (BUN): 20.1 +/- 14.1 versus 10.3 +/- 3.28 mg/dl] than those without HL(95) (P < 0.001). Of the females, 38% had HL(95). There was no significant association with cold perception deficit, creatinine or BUN in the females. Word recognition and acoustic reflexes analyses suggested a predominant cochlear involvement. We conclude that hearing loss involving all frequency regions significantly contributes to morbidity in patients with Fabry disease. Our quantitative analysis suggests a correlation of neuropathic and vascular damage with hearing loss in the males. Residual GALA activity appears to have a protective effect against hearing loss.

Comparison of 16S rRNA sequencing with conventional and commercial phenotypic techniques for identification of enterococci from the marine environment

AIMS

To compare accuracy of genus and species level identification of presumptive enterococci isolates from the marine environment using conventional biochemical testing, four commercial identification systems and 16S rRNA sequence analysis.

METHODS AND RESULTS

Ninety-seven environmental bacterial isolates identified as presumptive enterococci on mEI media were tested using conventional and Enterococcus genus screen biochemical tests, four commercial testing systems and 16S rRNA sequencing. Conventional and Enterococcus genus screen biochemical testing, 16S rRNA sequencing and two commercial test systems achieved an accuracy of > or = 94% for Enterococcus genus confirmation. Conventional biochemical testing and 16S rRNA sequencing achieved an accuracy of > or = 90% for species level identification.

CONCLUSIONS

For confirmation of Enterococcus genus from mEI media, conventional or genus screen biochemical testing, 16S rRNA sequencing and the four commercial systems were correct 79-100% of the time. For speciation to an accuracy of 90% or better, either conventional biochemical testing or 16S rRNA sequencing is required.

SIGNIFICANCE AND IMPACT OF THE STUDY

Accurate identification of presumptive environmental Enterococcus isolates to genus and species level is an integral part of laboratory quality assurance and further characterization of Enterococcus species from pollution incidents. This investigation determines the ability of six different methods to correctly identify environmental isolates.

Enumeration and speciation of enterococci found in marine and intertidal sediments and coastal water in southern California

AIMS

To determine the levels and species distribution of enterococci in intertidal and marine sediments and coastal waters at two beaches frequently in violation of bacterial water standards.

METHODS AND RESULTS

Faecal indicator bacteria were extracted from sediment and enumerated using membrane filtration. High levels of enterococci were detected in intertidal sediments in a seasonal river and near a storm drain outlet. Low levels were found in marine sediments at 10 m depths and in surf zone sand. Bacterial isolates presumptively identified as Enterococcus on mEI media were speciated. The predominant species found in both water and sediment included Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus casseliflavus and Enterococcus mundtii. A number of isolates (11-26%) from regulatory water samples presumptively identified as enterococci on mEI media were subsequently identified as species other than Enterococcus. At both study sites, the distribution of species present in water was comparable with those in sediments and the distribution of species was similar in water samples passing and exceeding bacterial indicator standards.

CONCLUSIONS

High levels of Enterococcus in intertidal sediments indicate retention and possible regrowth in this environment.

SIGNIFICANCE AND IMPACT OF THE STUDY

Resuspension of enterococci that are persistent in sediments may cause beach water quality failures and calls into question the specificity of this indicator for determining recent faecal contamination.

Evaluation of antibiotic resistance analysis and ribotyping for identification of faecal pollution sources in an urban watershed

AIMS

The accuracy of ribotyping and antibiotic resistance analysis (ARA) for prediction of sources of faecal bacterial pollution in an urban southern California watershed was determined using blinded proficiency samples.

METHODS AND RESULTS

Antibiotic resistance patterns and HindIII ribotypes of Escherichia coli (n = 997), and antibiotic resistance patterns of Enterococcus spp. (n = 3657) were used to construct libraries from sewage samples and from faeces of seagulls, dogs, cats, horses and humans within the watershed. The three libraries were analysed to determine the accuracy of host source prediction. The internal accuracy of the libraries (average rate of correct classification, ARCC) with six source categories was 44% for E. coli ARA, 69% for E. coli ribotyping and 48% for Enterococcus ARA. Each library's predictive ability towards isolates that were not part of the library was determined using a blinded proficiency panel of 97 E. coli and 99 Enterococcus isolates. Twenty-eight per cent (by ARA) and 27% (by ribotyping) of the E. coli proficiency isolates were assigned to the correct source category. Sixteen per cent were assigned to the same source category by both methods, and 6% were assigned to the correct category. Addition of 2480 E. coli isolates to the ARA library did not improve the ARCC or proficiency accuracy. In contrast, 45% of Enterococcus proficiency isolates were correctly identified by ARA.

CONCLUSIONS

None of the methods performed well enough on the proficiency panel to be judged ready for application to environmental samples.

SIGNIFICANCE AND IMPACT OF THE STUDY

Most microbial source tracking (MST) studies published have demonstrated library accuracy solely by the internal ARCC measurement. Low rates of correct classification for E. coli proficiency isolates compared with the ARCCs of the libraries indicate that testing of bacteria from samples that are not represented in the library, such as blinded proficiency samples, is necessary to accurately measure predictive ability. The library-based MST methods used in this study may not be suited for determination of the source(s) of faecal pollution in large, urban watersheds.

Elevated CNS average diffusion constant in Fabry disease

AIMS

Evaluation of the average brain diffusion constant in Fabry disease.

INTRODUCTION

Fabry disease is an X-linked recessive lysosomal storage disorder secondary to deficiency of alpha-galactosidase A and resulting in excess tissue globotriaosylceramide, particularly in cerebral blood vessels. This has been associated with cerebral hyperperfusion. Increased tissue perfusion should increase interstitial water by the Starling relationship. This hypothesis was examined by measuring the average CNS diffusion constant (Dav) in patients with Fabry disease using diffusion-weighted magnetic resonance imaging (DWI).

METHODS

Axial DWI was performed at b=0 seconds/mm2 and b = 1000 seconds/mm2 (TR (pulse repetition time), 10000; TE (time to echo), 100; FOV (field of view), 22 cm: 3 mm interleaved slices; image matrix, 128 x 128; GE Signa, 1.5T). Eight healthy male volunteers (age range, 21-47 years) and 17 hemizygous patients with Fabry disease (age range, 19-49 years) were examined. Following DWI acquisition, the trace image and the diffusion distribution map were calculated. The diffusion distribution curve was then fitted by a multi-modal Gaussian curve, allowing estimation of Dav.

RESULTS

The Dav was 0.743 +/- 0.024 x 10(-5) cm2/second (mean +/- SD) for patients with Fabry disease and 0.726 +/- 0.014 x 10(-5) cm2/second for the control group. Dav was significantly increased in the patients with Fabry disease compared with the controls (p = 0.029)

CONCLUSIONS

The elevated Dav indicates increased brain tissue water diffusivity in patients with Fabry disease, a finding consistent with increased extracellular water and increased cerebral blood flow.

Gemcitabine and oxaliplatin for metastatic pancreatic adenocarcinoma: a North Central Cancer Treatment Group phase II study

BACKGROUND

This study was performed to determine the efficacy of gemcitabine and oxaliplatin in patients with advanced or metastatic pancreatic adenocarcinoma (ACA).

PATIENTS AND METHODS

Pancreatic ACA patients with previously untreated advanced or metastatic disease were enrolled in a phase II study of gemcitabine and oxaliplatin. Oxaliplatin was given i.v. on day 1 and gemcitabine i.v. on days 1 and 8 of a 3-week cycle. The primary end point of the trial was 6-month survival. Secondary end points included response rate, overall survival, median time to progression and toxicity.

RESULTS

A total of 47 patients were enrolled, 46 of whom were evaluable. Of those patients assessed for the primary end point 50% lived for > or =6 months. The median time to progression was 4.53 months. Five confirmed responses were seen with a median duration of response of 2.7 months. Overall, the treatment was well tolerated. However, one patient died as a result of treatment-related hemolytic uremic syndrome.

CONCLUSIONS

Gemcitabine and oxaliplatin, at doses of 1000 mg/m(2) and 100 mg/m(2), respectively, showed moderate activity in patients with pancreatic ACA. Based on the results of this study further evaluation of this combination is warranted.

Comparison of total coliform, fecal coliform, and enterococcus bacterial indicator response for ocean recreational water quality testing

In July 1999, California's ocean recreational bacterial water quality standards were changed from a total coliform (TC) test to a standard requiring testing for all three bacterial indicators: TC, fecal coliforms (FC), and enterococci (EC). To compare the relationship between the bacterial indicators, and the effect that changing the standards would have on recreational water regulatory actions, three regional studies were conducted along the southern California shoreline from Santa Barbara to San Diego, California. Two studies were conducted during dry weather and one following a large storm event. In each study, samples were collected at over 200 sites which were selected using a stratified random design, with strata consisting of open beach areas and rocky shoreline, and areas near freshwater outlets that drain land-based runoff. During the dry weather studies, samples were collected once per week for 5 weeks. For the storm event study, sampling occurred on a single day about 24 h following the storm. The three indicator bacteria were measured at each site and the results were compared to the single sample standards (TC > 10,000; FC > 400 and EC > 104 MPN or cfu/100 ml). EC was the indicator that failed the single sample standards most often. During the wet weather study, 99% of all standard failures were detected using EC, compared with only 56% for FC, and 40% for TC. During the Summer Study, EC was again the indicator that failed the single sample standards most often, with 60% of the failures for EC alone. The increased failure of the EC standard occurred consistently regardless of whether the sample was collected at a beach or rocky shoreline site, or at a site near a freshwater outlet. Agreement among indicators was better during wet weather than during dry weather. During dry weather, agreement among indicators was better near freshwater outlets than along open shoreline. Cumulatively, our results suggest that replacement of a TC standard with an EC standard will lead to a five-fold increase in failures during dry weather and a doubling of failures during wet weather. Replacing a TC standard with one based on all three indicators will lead to an eight-fold increase in failures. Changes in the requirements for water quality testing have strong implications for increases in beach closures and restrictions.

The neurogenetics of mucolipidosis type IV

BACKGROUND

Mucolipidosis type IV (MLIV) is an autosomal recessive disease caused by mutations in the MCOLN1 gene that codes for mucolipin, a member of the transient receptor potential (TRP) gene family.

OBJECTIVE

To comprehensively characterize the clinical and genetic abnormalities of MLIV.

METHODS

Twenty-eight patients with MLIV, aged 2 to 25 years, were studied. Ten returned for follow-up every 1 to 2 years for up to 5 years. Standard clinical, neuroimaging, neurophysiologic, and genetic techniques were used.

RESULTS

All patients had varying degrees of corneal clouding, with progressive optic atrophy and retinal dystrophy. Twenty-three patients had severe motor and mental impairment. Motor function deteriorated in three patients and remained stable in the rest. All had a constitutive achlorhydria with elevated plasma gastrin level, and 12 had iron deficiency or anemia. Head MRI showed consistent characteristic findings of a thin corpus callosum and remained unchanged during the follow-up period. Prominent abnormalities of speech, hand usage, and swallowing were also noted. Mutations in the MCOLN1 gene were present in all patients. Correlation of the genotype with the neurologic handicap and corpus callosum dysplasia was found.

CONCLUSIONS

MLIV is both a developmental and a degenerative disorder. The presentation as a cerebral palsy-like encephalopathy may delay diagnosis.

Gemcitabine and oxaliplatin for patients with advanced or metastatic pancreatic cancer: a North Central Cancer Treatment Group (NCCTG) phase I study

BACKGROUND

The study was performed to determine the maximum tolerated dose (MTD) of gemcitabine and oxaliplatin in patients with advanced or metastatic pancreatic adenocarcinoma (ACA).

PATIENTS AND METHODS

Pancreatic ACA patients, with previously untreated advanced or metastatic disease, were enrolled in a dose escalation study of gemcitabine and oxaliplatin. Oxaliplatin was given intravenously on day 1 and gemcitabine intravenously on days 1 and 8 of a 3-week cycle. Doses of both drugs were increased with sequential cohorts of patients until dose-limiting toxicity (DLT) was observed.

RESULTS

A total of 18 patients were enrolled to three dose levels. DLT of neutropenia and a severe infection was noted at a dose of gemcitabine 1250 mg/m2 and oxaliplatin 130 mg/m2. Hematological toxicity and nausea and vomiting were the most common grade 3/4 toxicities. The MTD, gemcitabine 1000 mg/m2 and oxaliplatin 100 mg/m2, was well tolerated. Three confirmed responses were seen.

CONCLUSIONS

The MTD of gemcitabine and oxaliplatin in patients with pancreatic ACA was determined. A phase II study of this combination is ongoing and will be reported separately at a later date.

Local and global cerebral blood flow and glucose utilization in the alpha-galactosidase A knockout mouse model of Fabry disease

Fabry disease is an X-linked lysosomal disorder characterized by deficient alpha-galactosidase A activity and intracellular accumulations of glycosphingolipids, mainly globotriaosylceramide (Gb3). Clinically, patients occasionally present CNS dysfunction. To examine the pathophysiology underlying brain dysfunction, we examined glucose utilization (CMR(glc)) and cerebral blood flow (CBF) globally and locally in 18 brain structures in the alpha-galactosidase A gene knockout mouse. Global CMR(glc) was statistically significantly reduced by 22% in Fabry mice (p < 0.01). All 18 structures showed decreases in local CMR(glc) ranging from 14% to 33%. The decreases in all structures of the diencephalon, caudate-putamen, brain stem, and cerebellar cortex were statistically significant (p < 0.05). Global cerebral blood flow (CBF) and local CBF measured in the same 18 structures were lower in Fabry mice than in control mice, but none statistically significantly. Histological examination of brain revealed no cerebral infarcts but abundant Gb3 deposits in the walls of the cerebral vessels with neuronal deposits localized to the medulla oblongata. These results indicate an impairment in cerebral energy metabolism in the Fabry mice, but one not necessarily due to circulatory insufficiency.

Regional cerebral hyperperfusion and nitric oxide pathway dysregulation in Fabry disease: reversal by enzyme replacement therapy

BACKGROUND

Fabry disease is an X-linked lysosomal deficiency of alpha-galactosidase A that results in cellular accumulation of galacto-conjugates such as globotriosylceramide, particularly in blood vessels. It is associated with early-onset stroke and kidney and heart failure.

METHODS AND RESULTS

Using [(15)O] H(2)O and PET, we found increased resting regional cerebral blood flow in Fabry disease without evidence of occlusive vasculopathy or cerebral hypoperfusion. Because nitric oxide is known to play an important role in vascular tone and reactivity, we studied plasma nitrate, nitrite, and low-molecular-weight S-nitrosothiol levels by chemiluminescence. Skin biopsy specimens and archived brain tissue were also examined immunohistochemically for nitrotyrosine. Plasma nitrate, nitrite, and low-molecular-weight S-nitrosothiol were in the normal range; however, enhanced nitrotyrosine staining was observed in dermal and cerebral blood vessels. After a double-blind, placebo-controlled trial of alpha-galactosidase A therapy, the resting regional cerebral blood flow in the treated group was significantly reduced, with a notable decrease of nitrotyrosine staining in dermal blood vessels.

CONCLUSIONS

These findings suggest a chronic alteration of the nitric oxide pathway in Fabry disease, with critical protein nitration that is reversible with enzyme replacement therapy.

Selective arterial distribution of cerebral hyperperfusion in Fabry disease

Fabry disease is an X-linked recessive deficiency of lysosomal alpha-galactosidase A associated with an increased risk of early onset cerebrovascular disease. The disorder is reported to affect the posterior circulation predominantly. This hypothesis was investigated directly by the measurement of regional cerebral blood flow with positron emission tomography (PET). Resting regional cerebral blood flow (rCBF) in 26 hemizygous patients with Fabry disease and 10 control participants was examined using H(2)15O and PET. Statistical parametric mapping (SPM(t), SPM99) and PET images of patients and controls were produced. Significantly increased SPM(t) clusters were then color coded and blended with a coregistered T1 magnetic resonance imaging (MRI) template. Cerebral arterial territory maps were digitized and rescaled. Custom OpenGL and ImageVision Library C++ code was written to allow a first-order affine transformation of the blended SPM(t) and MRI template onto the arterial territory map. The affine transformation was constrained by choosing corresponding cerebral landmark "tie points" between the SPM(t) [symbol: see text] MRI template images and the cerebral arterial territory maps. The data demonstrated that the posterior circulation is the predominant arterial territory with a significantly increased rCBF in Fabry disease. No arterial distribution had a decreased rCBF.

Randomized phase III trial of paclitaxel plus carboplatin versus vinorelbine plus cisplatin in the treatment of patients with advanced non--small-cell lung cancer: a Southwest Oncology Group trial

PURPOSE

This randomized trial was designed to determine whether paclitaxel plus carboplatin (PC) offered a survival advantage over vinorelbine plus cisplatin (VC) for patients with advanced non--small-cell lung cancer. Secondary objectives were to compare toxicity, tolerability, quality of life (QOL), and resource utilization.

PATIENTS AND METHODS

Two hundred two patients received VC (vinorelbine 25 mg/m(2)/wk and cisplatin 100 mg/m(2)/d, day 1 every 28 days) and 206 patients received PC (paclitaxel 225 mg/m(2) over 3 hours with carboplatin area under the curve of 6, day 1 every 21 days). Patients completed QOL questionnaires at baseline, 13 weeks, and 25 weeks. Resource utilization forms were completed at five time points through 24 months.

RESULTS

Patient characteristics were similar between the groups. The objective response rate was 28% in the VC arm and 25% in the PC arm. Median survival was 8 months in both arms, with 1-year survival rates of 36% and 38%, respectively. Grade 3 and 4 leukopenia (P =.002) and neutropenia (P =.008) occurred more frequently on the VC arm. Grade 3 nausea and vomiting were higher on the VC arm (P =.001, P =.007), and grade 3 peripheral neuropathy was higher on the PC arm (P <.001). More patients on the VC arm discontinued therapy because of toxicity (P =.001). No difference in QOL was observed. Overall costs on the PC arm were higher than on the VC arm because of drug costs.

CONCLUSION

PC is equally efficacious as VC for the treatment of advanced non--small-cell lung cancer. PC is less toxic and better tolerated but more expensive than VC. New treatment strategies should be pursued.

Enhanced endothelium-dependent vasodilation in Fabry disease

BACKGROUND AND PURPOSE

Fabry disease is an X-linked lysosomal storage disease secondary to deficiency of alpha-galactosidase A with resulting glycolipid accumulation, particularly globotriaosylceramide in arterial smooth muscle and endothelial cells. A systemic vasculopathy, including early-onset stroke, is prevalent without a clear pathogenesis.

METHODS

Seventeen normotensive and normocholesterolemic hemizygous Fabry patients (aged 21 to 49 years) and 13 control subjects (aged 21 to 48 years) were investigated by venous plethysmography, allowing assessment of forearm blood flow. Plethysmographic measurements were obtained at baseline and during intra-arterial infusion of acetylcholine and sodium nitroprusside both with and without N(G)-monomethyl-L-arginine (L-NMMA).

RESULTS

Forearm blood flow was significantly higher in patients than in control subjects at all 3 acetylcholine doses (P=0.014). Patients had a greater response to acetylcholine even after the addition of L-NMMA (P=0.036).

CONCLUSIONS

These results demonstrate an increased endothelium-mediated vascular reactivity in Fabry disease. The increased vessel response to acetylcholine with and without L-NMMA suggests altered functionality of non-NO endothelium-dependent vasodilatory pathways.

Enzyme replacement therapy in Fabry disease: a randomized controlled trial

CONTEXT

Fabry disease is a metabolic disorder without a specific treatment, caused by a deficiency of the lysosomal enzyme alpha-galactosidase A (alpha-gal A). Most patients experience debilitating neuropathic pain and premature mortality because of renal failure, cardiovascular disease, or cerebrovascular disease.

OBJECTIVE

To evaluate the safety and efficacy of intravenous alpha-gal A for Fabry disease.

DESIGN AND SETTING

Double-blind placebo-controlled trial conducted from December 1998 to August 1999 at the Clinical Research Center of the National Institutes of Health.

PATIENTS

Twenty-six hemizygous male patients, aged 18 years or older, with Fabry disease that was confirmed by alpha-gal A assay.

INTERVENTION

A dosage of 0.2 mg/kg of alpha-gal A, administered intravenously every other week (12 doses total).

MAIN OUTCOME MEASURE

Effect of therapy on neuropathic pain while without neuropathic pain medications measured by question 3 of the Brief Pain Inventory (BPI).

RESULTS

Mean (SE) BPI neuropathic pain severity score declined from 6.2 (0.46) to 4.3 (0.73) in patients treated with alpha-gal A vs no significant change in the placebo group (P =.02). Pain-related quality of life declined from 3.2 (0.55) to 2.1 (0.56) for patients receiving alpha-gal A vs 4.8 (0.59) to 4.2 (0.74) for placebo (P =.05). In the kidney, glomeruli with mesangial widening decreased by a mean of 12.5% for patients receiving alpha-gal vs a 16.5% increase for placebo (P =.01). Mean inulin clearance decreased by 6.2 mL/min for patients receiving alpha-gal A vs 19.5 mL/min for placebo (P =.19). Mean creatinine clearance increased by 2.1 mL/min (0.4 mL/s) for patients receiving alpha-gal A vs a decrease of 16.1 mL/min (0.3 mL/s) for placebo (P =.02). In patients treated with alpha-gal A, there was an approximately 50% reduction in plasma glycosphingolipid levels, a significant improvement in cardiac conduction, and a significant increase in body weight.

CONCLUSION

Intravenous infusions of alpha-gal A are safe and have widespread therapeutic efficacy in Fabry disease.

Exploring extra-binomial variation in teratology data using continuous mixtures

Discrete data from animal teratology experiments are known to exhibit extra-binomial variation. For example, we discuss a dominant lethal assay experiment in which male mice are exposed to various levels of radiation and are then mated to females. The response of interest is the number of resorptions out of the number of implantations. Most statistical work on analyzing such data has focused on modeling response rates as a function of dose of a suspected teratogen (radiation in this case) while accounting for the extra-binomial variability when calculating standard errors of the regression coefficients. Sometimes, however, when an unobserved genetic or exposure variable is suspected, the shape of the mixing distribution is of interest. We propose a mixture of beta-binomials (MBB) family of distributions that includes the non-parametric mixture of binomials model of Laird (1978) as a special case. The MBB family can accommodate a mixing distribution with one or more modes, and we develop a bootstrap test for multimodality. We apply the method to data from a dominant lethal teratology experiment.

Evaluation of Tomudex in patients with recurrent or metastatic squamous cell carcinoma of the head and neck: a Southwest Oncology Group study

A phase II trial of Tomudex (raltitrexed, ZD 1694), a new thymidylate synthase inhibitor, was performed in patients with recurrent or metastatic squamous cell carcinoma of the head and neck. This trial demonstrated that Tomudex was well tolerated in this patient population. Nausea and vomiting were minimal, and hematologic toxicities were relatively infrequent. Only one patient was withdrawn from the study due to toxicity (grade 4 diarrhea). One patient exsanguinated from a rent in the carotid artery in an area of tumor involvement, and was categorized as a grade 5 toxicity. Thus 25/27 patients were able to complete at least 2 cycles of treatment. Tomudex demonstrated a 3.7% response rate (95% CI 0.1-19%), with a median survival of 6 months in this highly resistant disease population. Tomudex is not considered active enough as monotherapy for further evaluation in this disease population.

Phase II trial of 9-aminocamptothecin (NSC 603071) administered as a 120-hr continuous infusion weekly for three weeks in metastatic colorectal carcinoma

9-Aminocamptothecin (9-AC) is a camptothecin derivative with broad antitumor activity in preclinical studies. Prior investigations suggested that prolonged maintenance of 9-AC lactone plasma concentrations above 10 nmol/l and frequent administration of the drug are important determinants of antitumor activity. Our phase II study, therefore, examined a 5-day continuous infusion of 9-AC weekly for 3 weeks in patients with advanced colorectal cancer. Eighteen patients previously untreated for metastatic disease received 480 microg/m2/day of 9-AC. No responses were observed in 17 evaluable patients. Severe toxicities included granulocytopenia, nausea, vomiting and diarrhea. The median absolute granulocyte count (AGC) nadir was 2,300/microl (range 0-9,000/microl) and occurred on day 10. Eight patients received an escalated dose of 600 microg/m2/day. The median AGC nadir at the escalated dose was 1,500/microl (range: 300-2,700/microl) and occurred on day 22. The median number of courses given was 2 (range: 1-8); and the median time to disease progression was 8 weeks (range: 1-40 weeks). 9-AC administered by this schedule lacked antitumor activity in patients with advanced colorectal carcinomas.

Evidence for neuroaxonal injury in patients with proteolipid protein gene mutations

The authors used proton MRS to investigate neuropathologic correlates in nine patients with proteolipid protein (PLP) gene mutations who did not show cerebral atrophy on cranial MRI. When compared with 16 age-matched control participants, patients with PLP mutations had significant and widespread decreased brain N-acetyl aspartate, a neuronal marker. The authors conclude that PLP mutations cause neuroaxonal injury, which in turn contributes to the neurologic deficit observed in these patients.

Pseudo-likelihood estimates of the cumulative risk of an autosomal dominant disease from a kin-cohort study

Wacholder et al. [1998: Am J Epidemiol 148:623-629] and Struewing et al. [1997: N Engl J Med 336:1401-1408] have recently proposed a design called the kin-cohort design to estimate the probability of developing disease (penetrance) associated with an autosomal dominant gene. In this design, volunteers (probands) agree to be genotyped and one also determines the disease history (phenotype) of first-degree relatives of the proband. They used this design to estimate that the chance of developing breast cancer by age 70 in Ashkenazi Jewish women who carried mutations of the genes BRCA1 or BRCA2 was 0.56, a figure that was lower than previously estimated from highly affected families. The method that they used to estimate the cumulative risk of breast cancer, while asymptotically correct, does not necessarily produce monotone estimates in small samples. To obtain monotone, weakly parametric estimates, we consider separate piecewise exponential models for carriers and non-carriers. As the number of intervals on which constant hazards are assumed increases, however, the maximum likelihood score equations become unstable and difficult to solve. We, therefore, developed alternative pseudo-likelihood procedures that are readily solvable for piecewise exponential models with many intervals. We study these techniques through simulations and a re-analysis of a portion of the data used by Struewing et al. [1997] and discuss possible extensions.

Enzyme replacement therapy in Fabry disease

Recent clinical trials have demonstrated that enzyme replacement therapy with alpha-galactosidase A (alpha-Gal A) constitutes a major clinical advance in the treatment of patients with Fabry disease. This new therapeutic approach has been shown to be well tolerated and effective in reducing levels of the storage product globotriaosylceramide and in normalizing many of the debilitating manifestations of the disorder. A double-blind placebo-controlled trial in 26 hemizygous male patients showed that agalsidase alfa (human alpha-Gal A) significantly reduced neuropathic pain (p = 0.02), increased creatinine clearance (p = 0.02), improved glomerular histology, reduced the QRS interval on electrocardiography and increased weight gain. Positron emission tomography also revealed normalization of cerebrovascular flow. After the 6-month controlled period, all patients were given agalsidase alfa for a further 12 months. At the end of this period, all patients had a decrease in neuropathic pain, and there was a significant improvement in their ability to sense heat and cold. In addition, renal function stabilized, even in patients with renal insufficiency at the onset of treatment, and patients reported a normalization of sweating and improvements in their level of energy and sense of well-being. These findings show that enzyme replacement therapy offers promise as an effective management strategy for patients with Fabry disease.

Phase II evaluation of interleukin-4 in patients with non-Hodgkin's lymphoma: a Southwest Oncology Group trial

We performed a phase II, Southwest Oncology Group (SWOG) clinical trial of recombinant human interleukin-4 (rhuIL-4) in patients with previously treated non-Hodgkin's lymphoma (NHL). We studied 18 eligible patients with low-grade and 21 patients with intermediate- or high-grade NHL. All patients had received prior chemotherapy. A protocol amendment after the first four patients reduced the frequency of s.c. rhuIL-4 administration from daily to 3 times per week at 3 microg/kg and limited the number of prior chemotherapy regimens allowed. We documented no complete or partial responses in the low-grade NHL group [0%; 95% confidence interval (CI) 0-19%]. One patient in the intermediate/high-grade NHL group developed a partial response lasting longer than 15 months (5%; 95% CI 0-24%). Median survivals for the low- and intermediate/high-grade NHL groups were 15 and 13 months, respectively. Common toxicities included: arhralgia/myalgia, fatigue/malaise/lethargy, fever, headache, nausea and rigors/chills. Cardiac toxicity, gastrointestinal ulceration and nasal congestion due to rhuIL-4 were not prominent toxicities in our patients. Our previously treated NHL patients tolerated s.c. rhuIL-4 at a dose of 3 microg/kg given 3 times per week, but objective response rarely occurred. Further evaluation of rhuIL-4 in these patient populations does not appear warranted.

Comparative efficacy of dose regimens in enzyme replacement therapy of type I Gaucher disease

Gaucher disease is caused by a deficiency of beta-glucocerebrosidase activity. The optimum dose and frequency of enzyme replacement therapy for Gaucher patients have not been determined. We set to compare the therapeutic effects of initiating treatment with macrophage-targeted glucocerebrosidase at a high dose followed by progressive dose reductions with that produced by initial treatment at a low dose in patients with type I Gaucher disease. The study included two parts: (i) Twelve patients received every 2 weeks enzyme replacement therapy at 60 IU/kg body wt for 24 months followed by sequential dose reduction every 6 months to 30 and then to 15 IU/kg body wt. (ii) Thirty-two patients received enzyme replacement therapy at 10 IU/kg every 2 weeks for 12 months. Hematologic parameters and liver and spleen volume were monitored in all patients. All patients had intact spleens. In patients who were started on high-dose enzyme replacement therapy, hemoglobin, acid phosphatase, and organ volume improved or remained unchanged at the end of each dose reduction. Platelet count decreased significantly when the dose of enzyme was reduced from 30 to 15 IU/kg body wt. Initiation of therapy at a low dose led to a significant improvement in all measured parameters at the end of 1 year. We conclude that the minimal effective dose for the nonskeletal manifestations of Gaucher disease can be achieved either by initiating enzyme replacement therapy with a high dose followed by a stepwise dose reduction or by starting treatment at the minimal dose. High dose provides a faster clinical response and should be considered for patients with more aggressive disease. The therapeutic threshold for macrophage-targeted glucocerebrosidase appears to be 10-15 IU/kg body wt every 2 weeks.

A phase II trial of etoposide, leucovorin, 5-FU, and interferon alpha 2b (ELFI) + G-CSF for patients with pancreatic adenocarcinoma: a Southwest Oncology Group study (SWOG 9413)

BACKGROUND

Chemotherapeutic treatments using combinations of etoposide, leucovorin and 5-FU (ELF) have shown activity in the treatment of gastrointestinal malignancies. Interferon alpha 2b is known to have antiproliferative effects on several cell lines and has well documented in vitro evidence of synergism with 5-FU. It was postulated that the combination of ELF and interferon alpha 2b would improve response rates and survival in patients with pancreas cancer.

METHODS

Fifty-five eligible patients with locally-advanced or metastatic pancreatic adenocarcinoma received a regimen consisting of: i.v. leucovorin at 300 mg/m2/day on Days 1-3 (of 28-day cycle), i.v. etoposide at 80 mg/m2/day on Days 1-3, i.v. 5-FU at 500 mg/m2/day on Days 1-3, subcutaneous interferon alpha 2b at 3 million units TIW, and subcutaneous G-CSF at 5 microg/kg/day on Days 4-14 (or until WBC exceeds 10,000/microl). Patients with no evidence of disease progression continued on treatment for a total of 6 cycles.

RESULTS

Complete response was demonstrated in 1 patient, partial response in 5 patients (11% confirmed response rate). The median survival was 5 months, and the six-month survival rate was 40%. Ten patients completed all 6 cycles of treatment. Toxicity-related dose delays and reductions were necessary for most patients.

CONCLUSIONS

Although the combination of ELF and interferon alpha 2b (ELFI) has modest activity in pancreatic cancer, it is a toxic and complex regimen that is not superior to other currently available approaches for the chemotherapeutic management of pancreatic cancer. ELFI cannot be recommended as a standard therapy.