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Stephen Johnson

Publications and source records attributed to Stephen Johnson.

13 recordsLinked to original sources
PubMed2006

Update on treatment recommendations from the Third International Workshop on Waldenstrom's macroglobulinemia.

Waldenström macroglobulinemia (WM) is a B-cell disorder characterized by the infiltration of lymphoplasmacytic cells into bone marrow and the presence of an IgM monoclonal gammopathy. As part of the Third International Workshop on WM, held October 7 to 10, 2004 in Paris, France, a consensus panel charged with providing treatment recommendations for WM updated its recommendations on both frontline and salvage therapies. The panel considered encouraging results from recent studies that addressed the use of extended-dose rituximab as well as other treatment options: therapy with either nucleoside analogs and alkylator agents, rituximab in combination with nucleoside analogs, nucleoside analogs plus alkylator agents, or combination chemotherapies, such as CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) or cyclophosphamide and dexamethasone. The panel determined that these were reasonable treatment options for WM patients and such therapeutic approaches were likely to yield results that are at least as good as if not better than the currently recommended use of single-agent alkylator, nucleoside analog, or standard-dose rituximab therapy. Such approaches were deemed to be reasonable treatment for WM patients in both the upfront and salvage settings, though randomized studies addressing the efficacy and toxicity of such novel approaches over previously established standard of care options are needed.

Alkylating Agents↗
PubMed2006

The role of TIPS for portal vein patency in liver transplant patients with portal vein thrombosis.

The purpose of this research was to study the efficacy and outcomes of transjugular intrahepatic shunt (TIPS) in end-stage liver disease (ESLD) patients with portal vein thrombosis (PVT) eligible for orthotopic liver transplant. Nine consecutive patients with PVT underwent TIPS as a nonemergent elective outpatient procedure. The primary indication for TIPS was to maintain portal vein patency for optimal surgical outcome. Eight patients underwent contrast enhanced computed tomography (CT) and 1 magnetic resonance imaging diagnosing PVT. Shunt creation was determined by available targets at the time of TIPS and by prior imaging. Patients were followed with portography, ultrasound, CT, or magnetic resonance imaging, and the luminal occlusion was estimated before and after TIPS. Primary endpoints were transplantation, removal from the transplant list, or death. Stabilization, improvement, or complete resolution of thrombosis was considered successful therapy. Failures included propagation of thrombosis or vessel occlusion, and poor surgical anatomy due to PVT. Of 9 patients with PVT, TIPS was successfully placed in all patients without complication or TIPS-related mortality. Eight of 9 patients (88.8%) had improvement at follow-up. One patient failed therapy and re-thrombosed. Two patients (22.2%) were transplanted without complication and had no PVT at the time of transplant. Eight of 9 patients were listed for transplant at the time of their TIPS. Eight of 9 PVTs were nonocclusive. Four of 9 patients (44%) had evidence of cavernous transformation. Two patients expired during follow-up 42 and 44 months after TIPS. Three patients remain on the transplant list. One patient has not been listed due to nonprogression of disease. One patient has been removed from the transplant list because of comorbid disease. In conclusion, TIPS is safe and effective in patients with PVT and ESLD requiring transplant. Patients can be successfully transplanted with optimal surgical anatomy.

Adult↗
PubMed2006

Update on recommendations for assessing response from the Third International Workshop on Waldenstrom's Macroglobulinemia.

This report by an international consensus panel updates current recommendations for defining clinical response in Waldenstrom's macroglobulinemia (WM). The previously published response criteria incorporated parameters for monoclonal protein reduction and/or improvement of marrow and nodal involvement, and included definitions of complete and partial remissions. The criteria have been updated to include minor response and stable disease categories. In addition, the criteria now recognize that delayed responses after treatment with nucleoside analogues and biologic agents and the time point for assessing response in patients with WM should be considered so as to not miss or miscategorize a response. The new criteria should therefore help in better delineating responses to therapy in patients with WM, particularly with the wide use of nucleoside analogues and biologically based agents for this disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2005

Splenic marginal zone lymphoma.

Splenic marginal zone lymphoma (SMZL) is an indolent B cell malignancy usually involving spleen, bone marrow and blood. The disease presents as an incidental finding or with symptoms of splenic enlargement or anaemia. Diagnosis is based on a combination of lymphocyte morphology, immunophenotype and marrow and /or splenic histology. There is no genetic abnormality specific for SMZL, but deletions of chromosome 7q are the commonest abnormality and are found in 30-50% of cases. SMZL cells may have either mutated or unmutated immunoglobulin variable region genes and probably arise from different subsets of splenic marginal zone B cells. Prognostic factors are poorly defined and only loss or mutation of the p53 gene is consistently associated with a poor outcome. Therapeutic options include splenectomy, splenic irradiation, alkylating agents, purine analogues or anti CD20 antibody. The median survival is 10-13 years and most disease-related deaths are associated with transformation to diffuse large cell lymphoma.

DNA Mutational Analysis↗
PubMed2005

Racial/ethnic differences in screening for colon cancer: report from the New York Cancer Project.

OBJECTIVE: To determine whether racial/ethnic differences in colon cancer screening are independent of socioeconomic and personal risk factors. DESIGN: Baseline cross-section for a prospective cohort. METHOD: We recruited adults between 2000 and 2002 to undergo a questionnaire and venipuncture to study cancer risks. RESULTS: Among 5595 adults over 50 years old, 40.3% reported sigmoidoscopy or colonoscopy within the prior five years; rates were 48.0% for Whites, 32.8% for Blacks, 27.9% for Hispanics, 30.3% for Asians, and 33.3% for others. Adjusting for age, gender, access to care (as income and insurance), and risk profile (as cancer in family, smoking, and obesity), Blacks and Hispanics were less likely to have been screened than Whites. CONCLUSIONS: Screening for colon cancer is low, especially among racial/ethnic minorities. Sociocultural factors merit closer attention.

Adult↗
PubMed2004

Management of low-output pancreatic fistulas with fibrin glue.

BACKGROUND: Despite advances in surgical, endoscopic, and percutaneous therapeutic techniques, pancreatic fistulas remain a source of significant morbidity and long-term patient discomfort. The intraoperative use of fibrin sealant has been used prophylactically to prevent formation of fistula. We recognized the potential use of fibrin glue as a therapeutic modality for successful resolution of low-output pancreatic fistulas. METHODS: Three patients with low (<20 ml per day) output pancreatic fistulas underwent fluoroscopically directed injection of fibrin glue along their fistula tract. RESULTS: All 3 patients underwent successful fibrin glue injection without procedural complication. All fistula output stopped, and the 3 patients remained asymptomatic at 1 year. CONCLUSIONS: Fibrin glue inserted with image-guided catheter delivery systems may be a useful option in selected patients with low-output pancreatic fistulas.

Female↗
PubMed2004

The New York Cancer Project: rationale, organization, design, and baseline characteristics.

Cancer is the second leading cause of death in New York City, with nearly 15,000 deaths each year. The urban setting of New York City provides ready access to large and diverse populations for whom racial/ethnic disparities in cancer risk and outcomes can be examined. A new cohort study was undertaken with several aims: (1) to provide a database and biorepository for studies of cancer etiology and pathogenesis, including host genetics; (2) to differentiate risk factors that contribute to racial/ethnic disparities in cancer risk, prevention, control, incidence, mortality, and survival; (3) to provide timely data on cancer risk and preventive behaviors that can be used to mobilize and then evaluate public health programs. Scientists from multiple institutions contributed to protocol design and implementation. Study instruments included demographics, personal and family history of cancer, risk and prevention efforts. End points include linkage with registries and medical record reviews. Using venue-based sampling with quotas, 18,187 adults aged 30 years or older were recruited over a year to undergo a baseline questionnaire, venipuncture, and contact information. The sample was 39% male, 37% older than 50 years, 58% white, 20% African American, 18% Hispanic, and 9% Asian. In terms of family history of cancer, 21% reported mother, 21% reported father, and 5.9% reported both parents with cancer; 8.5% reported any sibling with cancer. At baseline, 1,231 participants reported prior cancer. Showing the feasibility of constructing a cohort based in New York City, plans proceed for additional recruitment and analyses on the salient questions about cancer.

Epidemiologic Research Design↗
PubMed2004

Hepatic artery chemoembolization for hepatocellular carcinoma in patients listed for liver transplantation.

We retrospectively analyzed all listed patients having hepatic artery chemoembolization (HACE) for hepatocellular carcinoma (HCC) stage T2 or less. Outcomes were transplantation, waiting list removal, death, and HCC recurrence. Twenty patients (mean age 55.7 years; 15 males) were identified. Twelve (60%) were transplanted, seven (35%) were removed from the list and one (5%) remains listed. Fourteen (70%) are alive. All 12 transplanted patients are alive (mean 2.94 years); one of seven removed from the list is alive (mean 1.45 years). Survival was significantly higher for those transplanted or listed vs. removed from the list (100% vs. 14.3%, p = 0.0002). No HCC's recurred. Three patients (15%) were removed from the list after prolonged waiting times before MELD. Hepatic artery chemoembolization induced deterioration and removal from the list of one (5%) patient. Survival for those transplanted was excellent(100%), but overall survival was significantly lower (61.3%) at a mean 5.48 years. Hepatic artery chemoembolization for listed patients with <or=euro T2 stage HCC is beneficial, but must be weighed against decreased waiting times and risk of HACE-induced deterioration. This balance is influenced greatly by the MELD system's determination of waiting times for HCC patients.

Carcinoma, Hepatocellular↗
PubMed2004

A comparison of semantic categories of the ISO reference terminology models for nursing and the MedLEE natural language processing system.

Natural language processing (NLP) systems have demonstrated utility in parsing narrative texts for purposes such as surveillance and decision support. However, there has been little work related to NLP of nursing narratives. The purpose of this study was to compare the semantic categories of a NLP system (Medical Language Extraction and Encoding [MedLEE] system) with the semantic domains, categories, and attributes of the International Standards Organization(ISO) reference terminology models for nursing diagnoses and nursing actions. All but two MedLEE diagnosis and procedure-related semantic categories mapped to ISO models. In some instances, we found exact correspondence between the semantic structures of MedLEE and the ISO models. In other situations (e.g. aspects of site or location), the ISO model was not as granular as MedLEE. For clinical procedure and non-invasive examination, two ISO nursing action model components (action and target) were required to represent the MedLEE semantic category. The ISO model requires additional specification of selected semantic categories for the abstract semantic domains in order to achieve the objective of using NLP to parse and encode data from nursing narratives. Our analysis also suggests areas for extension of MedLEE.

Natural Language Processing↗
PubMed2003

Practice parameters for using polysomnography to evaluate insomnia: an update.

Insomnia is a common and clinically important problem. It may arise directly from a sleep-wake regulatory dysfunction and/or indirectly result from comorbid psychiatric, behavioral, medical, or neurological conditions. As an important public-health problem, insomnia requires accurate diagnosis and effective treatment. Insomnia is primarily diagnosed clinically with a detailed medical, psychiatric, and sleep history. Polysomnography is indicated when a sleep-related breathing disorder or periodic limb movement disorder is suspected, initial diagnosis is uncertain, treatment fails, or precipitous arousals occur with violent or injurious behavior. However, polysomnography is not indicated for the routine evaluation of transient insomnia, chronic insomnia, or insomnia associated with psychiatric disorders.

Chronic Disease↗
PubMedDate not supplied

Incidence of contraindications to total disc arthroplasty: a retrospective review of 100 consecutive fusion patients with a specific analysis of facet arthrosis.

BACKGROUND CONTEXT: The role of total disc arthroplasty (TDA) in the treatment of spinal pathology is unclear. TDA has been touted as an alternative to fusion. However, not all back pain is purely discogenic in origin. Contraindications to TDA exist. At Spine Week in Porto, Portugal, Cammisa's group from the Hospital for Special Surgery in New York presented a series of 56 fusions where 100% of patients had one or more of 10 contraindications to TDA. En face, this appears to be an extremely large number. PURPOSE: The purpose of the study was to repeat the Hospital for Special Surgery study in another cohort of fusion patients. STUDY DESIGN/SETTING: This study was an independent, retrospective record review of 100 consecutive lumbar spinal fusions performed at a tertiary care private medical center. PATIENT SAMPLE: All adult patients having primary1-3 level lumbar spinal fusions from January 2003 to May 2004 were assessed. OUTCOME MEASURES: Physiologic measures included imaging, range of motion, and response to facet blocks. METHODS: A retrospective chart review was performed of 100 consecutive patients having primary 1-3 level lumbar fusion by all five active staff spinal surgeons (3 orthopedic and 2 neurosurgeons). The review was performed independently by the doctorate level physiotherapist who serves as the medical center's research coordinator, reporting to the chairman of the Hospital institutional review board. The same 10 contraindications from Cammisa's study were noted. Additional facet arthrosis data were collected, including mention on imaging reports or operating room notes. Clinical notes were reviewed for documentation of range of lumbar motion (ROM) and whether there was restricted or painful extension ROM. Note was made if patients had facet blocks as another clinical indicator of facet arthrosis. RESULTS: All 100 patients had at least one contraindication to TDA. The average was 3.69 (range 1-7). Only one patient had facet arthrosis as their only contraindication. Facet arthrosis was documented on imaging reports or operating room notes in 97/100. Reduced extension was present in 71/75 charts that documented ROM. Facet blocks were performed in 12/100 and gave greater than 50% relief in nine. CONCLUSIONS: Both our study and Cammisa's indicate that all lumbar fusion patients in our two institutions have at least one contraindication to TDA. The average fusion patient does not appear to have isolated discogenic pain. A large proportion of the patients appeared to have facet arthritis. The point where facet arthrosis definitely constitutes a contradiction to TDA will require analysis during long-term arthroplasty follow-up studies. Suitable patients for TDA may not represent a significant cohort presently undergoing lumbar fusion.

Adult↗