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John J Crowley

Publications and source records attributed to John J Crowley.

At least 19 recordsLinked to original sources

Impact of the year 2000 Medicare policy change on older patient enrollment to cancer clinical trials.

PURPOSE: A prior analysis by the Southwest Oncology Group (SWOG) showed that women and African American patients were adequately represented on cancer clinical treatment trials but that older patients were substantially underrepresented. Twenty-five percent of patients > or = 65 years old were enrolled onto SWOG trials from 1993 to 1996, whereas 63% of all patients with cancer were > or = 65 years old. Recognition of this under-representation led to a change in Medicare policy in 2000 to include coverage of routine patient care costs of clinical trials. We conducted an updated analysis of accrual trends. METHODS: The proportions of enrollment onto SWOG treatment trials by sex, race/ethnicity, and age (> or = 65 years) were computed for the years 1997 to 2000; corresponding rates in the United States were derived from US Census and National Cancer Institute Surveillance, Epidemiology, and End results data. Additionally, method of payment data were analyzed over time (1993 to 2003) to assess whether patterns in method of payment changed with the new Year 2000 Medicare policy on clinical trials coverage. RESULTS: The results showed continued adequate representation by sex and race/ethnicity. Older patient accrual on SWOG trials increased significantly since 2000, with 31% of patients > or = 65 years old enrolled from 1997 to 2000 and 38% enrolled from 2001 to 2003 (v 25% from 1993 to 1996). The percentage of patients using Medicare plus supplemental insurance also increased beginning in 2000, whereas the percentage of patients using Medicare alone remained the same. CONCLUSION: Method of payment analyses provided evidence that the Year 2000 Medicare policy change had a positive impact, but only for those patients with supplemental private coverage of coinsurance costs. Improvements in the Medicare payment structure could further increase older patient participation in clinical trials.

Aged↗

Operating characteristics of prostate-specific antigen in men with an initial PSA level of 3.0 ng/ml or lower.

CONTEXT: Three fourths of US men older than 50 years have been screened with prostate-specific antigen (PSA) for prostate cancer. OBJECTIVE: To estimate the receiver operating characteristic (ROC) curve for PSA. DESIGN, SETTING, AND PARTICIPANTS: Calculation of PSA ROC curves in the placebo group of the Prostate Cancer Prevention Trial, a randomized, prospective study conducted from 1993 to 2003 at 221 US centers. Participants were 18 882 healthy men aged 55 years or older without prostate cancer and with PSA levels less than or equal to 3.0 ng/mL and normal digital rectal examination results, followed up for 7 years with annual PSA measurement and digital rectal examination. If PSA level exceeded 4.0 ng/mL or rectal examination result was abnormal, a prostate biopsy was recommended. After 7 years of study participation, an end-of-study prostate biopsy was recommended in all cancer-free men. MAIN OUTCOME MEASURES: Operating characteristics of PSA for prostate cancer detection, including sensitivity, specificity, and ROC curve. RESULTS: Of 8575 men in the placebo group with at least 1 PSA measurement and digital rectal examination in the same year, 5587 (65.2%) had had at least 1 biopsy; of these, 1225 (21.9%) were diagnosed with prostate cancer. Of 1213 cancers with Gleason grade recorded, 250 (20.6%) were Gleason grade 7 or greater and 57 (4.7%) were Gleason grade 8 or greater. The areas under the ROC curve (AUC) for PSA to discriminate any prostate cancer vs no cancer, Gleason grade 7 or greater cancer vs no or lower-grade cancer, and Gleason grade 8 or greater cancer vs no or lower-grade cancer were 0.678 (95% confidence interval [CI], 0.666-0.689), 0.782 (95% CI, 0.748-0.816), and 0.827 (95% CI, 0.761-0.893), respectively (all P values <.001 for AUC vs 50%). For detecting any prostate cancer, PSA cutoff values of 1.1, 2.1, 3.1, and 4.1 ng/mL yielded sensitivities of 83.4%, 52.6%, 32.2%, and 20.5%, and specificities of 38.9%, 72.5%, 86.7%, and 93.8%, respectively. Age-stratified analyses showed slightly better performance of PSA in men younger than 70 years vs those 70 years or older with AUC values of 0.699 (SD, 0.013) vs 0.663 (SD, 0.013) (P = .03). CONCLUSION: There is no cutpoint of PSA with simultaneous high sensitivity and high specificity for monitoring healthy men for prostate cancer, but rather a continuum of prostate cancer risk at all values of PSA.

Aged↗

Time from treatment to subsequent diagnosis of brain metastases in stage III non-small-cell lung cancer: a retrospective review by the Southwest Oncology Group.

PURPOSE A retrospective review of the Southwest Oncology Group (SWOG) database was undertaken to review the incidence and timing of diagnosis of brain metastases in patients undergoing combined-modality therapy for stage III non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Four hundred twenty-two eligible, assessable patients with stage IIIA/B NSCLC were treated on four SWOG protocols. Treatment varied with protocol but consisted of concurrent cisplatin-etoposide and radiation in all patients, with a surgery arm in two of the four protocols. Results Of the 422 total patients, 268 (64%) have experienced disease progression; 54 relapses (20%) were in brain only, 17 (6.5%) were in brain and other sites simultaneously, and 197 (63.5%) were in sites other than brain. Of the 268 patients with disease progression, progression in the brain only, in the brain and other sites, and not in the brain occurred in 20%, 6%, and 74% of patients, respectively. Time from treatment to diagnosis of disease progression in the brain in 71 patients was as follows: during treatment, 16 relapses (22.5%); 0 to 16 weeks after treatment, 17 relapses (24%); 16 weeks to 6 months after treatment, 10 relapses (14%); 6 to 12 months after treatment, 16 relapses (22.5%); and more than 12 months after treatment, 12 relapses (17%). Nonsquamous histology and young patient age were the only significant predictors for increased risk of early relapse with brain metastases. CONCLUSION Brain metastases often develop early in the course of treatment for stage IIIA/B NSCLC. The statistical designs of ongoing trials of prophylactic cranial irradiation in stage III NSCLC have taken this into account.

Antineoplastic Combined Chemotherapy Protocols↗

Distinct structural features of phospholipids differentially determine ethanol sensitivity and basal function of BK channels.

Large conductance Ca2+ -activated K+ (BK) channel activity and its potentiation by ethanol are both critically modulated by bilayer phosphatidylserine (PS), a phospholipid involved in membrane-bound signaling. Whether PS is uniquely required for ethanol to modify channel activity is unknown. Furthermore, the structural determinants in membrane phospholipid molecules that control alcohol action remain to be elucidated. We addressed these questions by reconstituting BK channels from human brain (hslo) into bilayers that contained phospholipids differing in headgroup size, charge, and acyl chain saturation. Data demonstrate that ethanol potentiation of hslo channels is blunted by conical phospholipids but favored by cylindrical phospholipids, independently of phospholipid charge. As found with ethanol action, basal channel activity is higher in bilayers containing cylindrical phospholipids. Basal activity and its ethanol potentiation in bilayers containing phosphatidylcholine, however, are not as robust as in those containing PS. These results are best interpreted as resulting from the relief of bilayer stress caused by inclusion of cylindrical phospholipids, with this relief being synergistically evoked by molecular shape and negative headgroup charge. Present findings suggest that hslo gating structures targeted by ethanol are accessible to sense changes in bilayer stress. In contrast, hslo unitary conductance is significantly higher in bilayers that contain negatively charged phospholipids independently of molecular shape, a result that is likely to be dependent on an interaction between anionic phospholipids and deep channel residues coupled to the selectivity filter.

Cell Line↗

International staging system for multiple myeloma.

PURPOSE: There is a need for a simple, reliable staging system for multiple myeloma that can be applied internationally for patient classification and stratification. PATIENTS AND METHODS: Clinical and laboratory data were gathered on 10,750 previously untreated symptomatic myeloma patients from 17 institutions, including sites in North America, Europe, and Asia. Potential prognostic factors were evaluated by univariate and multivariate techniques. Three modeling approaches were then explored to develop a staging system including two nontree and one tree survival assessment methodologies. RESULTS: Serum beta2-microglobulin (Sbeta2M), serum albumin, platelet count, serum creatinine, and age emerged as powerful predictors of survival and were then used in the tree analysis approach. A combination of Sbeta2M and serum albumin provided the simplest, most powerful and reproducible three-stage classification. This new International Staging System (ISS) was validated in the remaining patients and consists of the following stages: stage I, Sbeta2M less than 3.5 mg/L plus serum albumin > or = 3.5 g/dL (median survival, 62 months); stage II, neither stage I nor III (median survival, 44 months); and stage III, Sbeta2M > or = 5.5 mg/L (median survival, 29 months). The ISS system was further validated by demonstrating effectiveness in patients in North America, Europe, and Asia; in patients less than and > or = 65 years of age; in patients with standard therapy or autotransplantation; and in comparison with the Durie/Salmon staging system. CONCLUSION) The new ISS is simple, based on easy to use variables (Sbeta2M and serum albumin), and recommended for early adoption and widespread use.

Age Factors↗

Estimated impact of the Prostate Cancer Prevention Trial on population mortality.

BACKGROUND: The potential public health impact of the recently completed Prostate Cancer Prevention Trial (PCPT) is debated. The results indicated that the period prevalence of prostate cancer was reduced by 24.8% due to finasteride, whereas an increase in the rate of high-grade tumors (Gleason score 8-10) among men who were diagnosed with cancer also was found (5.0% in the PCPT placebo arm vs. 11.9% in the PCPT finasteride arm). Whether the increased Gleason score was valid or was a histologic artifact is under investigation. METHODS: The authors estimated the number of person-years saved assuming a 24.8% reduction in the incidence of prostate cancer for 5 years among United States males age > or = 55 years. Scenarios for different proportions of patients with high-grade Gleason scores also were considered. RESULTS: With a 24.8% reduction in the number of men with newly diagnosed prostate cancer, the authors estimated that 316,760 person-years would be saved due to finasteride in the United States. An absolute increase of 6.9% in the proportion of men with high-grade tumors in the United States cancer population (corresponding to the difference between the rates on the placebo and finasteride arms of the PCPT) would reduce the number of person-years saved to 262,567. For each absolute increase of 5% in the proportion of patients with high-grade tumors, the number of person-years saved would be reduced by approximately 39,000. CONCLUSIONS: The results of the PCPT may have a major impact on population mortality from prostate cancer if they are applied clinically. The potential detrimental effects of an increased rate of patients who have prostate cancer with high-grade Gleason scores would be outweighed by a reduction in incidence.

Finasteride↗

Designing the Selenium and Vitamin E Cancer Prevention Trial (SELECT).

Prostate cancer continues to be a major health threat, especially among African American men. The Selenium and Vitamin E Cancer Prevention Trial (SELECT), which opened on July 25, 2001, was planned to study possible agents for the prevention of prostate cancer in a population of 32,400 men in the United States, including Puerto Rico, and Canada. SELECT is a phase III randomized, placebo-controlled trial of selenium (200 microg/day from L-selenomethionine) and/or vitamin E (400 IU/day of all rac alpha-tocopheryl acetate) supplementation for a minimum of 7 years (maximum of 12 years) in non-African American men at least 55 years of age and African American men at least 50 years of age. SELECT is a large, simple trial that conforms as closely as possible with community standards of care. This commentary discusses the design problems the SELECT investigators had to resolve in developing the trial, including the role of prostate cancer screening, the best forms and doses of the study agents, and estimation of the event (prostate cancer) rate of men on the placebo arm.

Black or African American↗

Phase I study of tirapazamine plus cisplatin/etoposide and concurrent thoracic radiotherapy in limited-stage small cell lung cancer (S0004): a Southwest Oncology Group study.

PURPOSE: To determine the feasibility and a recommended phase II dose of tirapazamine when combined with chemoradiotherapy in limited-stage small cell lung cancer (LSCLC). EXPERIMENTAL DESIGN: Concurrent chemoradiotherapy consisted of two cycles of cisplatin, etoposide, and once-daily radiation to 61 Gy. Tirapazamine (260 mg/m2) was given 1 h before cisplatin with planned dose escalation to 330 mg/m2 in the absence of dose-limiting toxicity, defined as > or =33% esophagitis (grade 3 or above). Consolidation therapy consisted of two cycles of tirapazamine (330 mg/m2), cisplatin, and etoposide. Complete responders received prophylactic cranial irradiation. RESULTS: Thirty patients were enrolled at the 260 mg/m2 tirapazamine dose. All had performance status of 0-1. By comparison with S9713, a predecessor Southwest Oncology Group study in LSCLC that used the same concurrent chemoradiotherapy without tirapazamine, the present trial showed a higher rate of grade 3-4 esophagitis (34% versus 22%), vomiting (34% versus 23%), and febrile neutropenia (7% versus 2%). The consolidation phase was relatively well tolerated, with grade 4 neutropenia in 44% and febrile neutropenia in 5% of patients. There were two treatment-related deaths: one from neutropenic fever and one from respiratory infection. The overall response rate was 80%, and the median survival was 22 months. CONCLUSIONS: Protocol-defined dose-limiting toxicity was observed at the initial tirapazamine dose, precluding dose escalation. Compared with S9713, the addition of tirapazamine increased the incidence of vomiting, neutropenia, and febrile neutropenia, although the overall toxicity profile remained acceptable. In view of the observed favorable survival, further study of tirapazamine in LSCLC is warranted.

Adult↗

Clinical efficacy of high-dose dexamethasone with maintenance dexamethasone/alpha interferon in patients with primary systemic amyloidosis: results of United States Intergroup Trial Southwest Oncology Group (SWOG) S9628.

Current therapy of primary systemic (AL) amyloidosis with oral melphalan and prednisone remains unsatisfactory, with a median survival of only 13 months. Between 1996 and 2003, 93 patients with biopsy-proven AL amyloidosis were enrolled in a prospective US national cooperative group trial. Treatment schema consisted of induction therapy with pulse dexamethasone (DEX), followed by maintenance therapy with DEX and alpha interferon. Hematologic complete remissions were observed in 24% and improvement in AL amyloidosis-related organ dysfunction occurred in 45% of patients evaluable for response. Median survival of the entire cohort is 31 months, with an estimated 2-year overall survival (OS) and event-free survival (EFS) of 60% and 52%, respectively. Presence of congestive heart failure and increased level of serum beta2 microglobulin (>/= 0.0035 g/L [3.5 mg/L]) were dominant predictors of adverse outcome. Estimated 2-year OS in patients who are eligible to receive transplants with this approach was 78%. These data demonstrate for the first time in the context of a US multicenter prospective clinical trial that front-line therapy with a DEX-based regimen in AL amyloidosis can lead to durable reversal of AL amyloidosis-related organ dysfunction and prolonged survival.

Aged↗

Prevalence of prostate cancer among men with a prostate-specific antigen level < or =4.0 ng per milliliter.

BACKGROUND: The optimal upper limit of the normal range for prostate-specific antigen (PSA) is unknown. We investigated the prevalence of prostate cancer among men in the Prostate Cancer Prevention Trial who had a PSA level of 4.0 ng per milliliter or less. METHODS: Of 18,882 men enrolled in the prevention trial, 9459 were randomly assigned to receive placebo and had an annual measurement of PSA and a digital rectal examination. Among these 9459 men, 2950 men never had a PSA level of more than 4.0 ng per milliliter or an abnormal digital rectal examination, had a final PSA determination, and underwent a prostate biopsy after being in the study for seven years. RESULTS: Among the 2950 men (age range, 62 to 91 years), prostate cancer was diagnosed in 449 (15.2 percent); 67 of these 449 cancers (14.9 percent) had a Gleason score of 7 or higher. The prevalence of prostate cancer was 6.6 percent among men with a PSA level of up to 0.5 ng per milliliter, 10.1 percent among those with values of 0.6 to 1.0 ng per milliliter, 17.0 percent among those with values of 1.1 to 2.0 ng per milliliter, 23.9 percent among those with values of 2.1 to 3.0 ng per milliliter, and 26.9 percent among those with values of 3.1 to 4.0 ng per milliliter. The prevalence of high-grade cancers increased from 12.5 percent of cancers associated with a PSA level of 0.5 ng per milliliter or less to 25.0 percent of cancers associated with a PSA level of 3.1 to 4.0 ng per milliliter. CONCLUSIONS: Biopsy-detected prostate cancer, including high-grade cancers, is not rare among men with PSA levels of 4.0 ng per milliliter or less--levels generally thought to be in the normal range.

Aged↗

Implementation of the Prostate Cancer Prevention Trial (PCPT).

The Prostate Cancer Prevention Trial is a randomized double blind chemoprevention trial of 18,882 men. It is designed to test the difference in the histologically proven prostate cancer prevalence between a group of participants given finasteride and another given placebo for 7 years. We present an overview of the study design, details of the administrative structure of the study and a description of the successful implementation of the accrual phase.

Chemoprevention↗

Statistical design issues and other practical considerations for conducting phase III prostate cancer prevention trials.

PURPOSE: We briefly describe the purpose of phase II studies as a source of preliminary data for phase III prevention trials, and address statistical and other practical considerations for phase III prostate cancer prevention trials. MATERIALS AND METHODS: Objectives of 2 types of phase II studies and general criteria for validating surrogate end points are described, and statistical considerations needed for planning a phase III prevention trial are explained, including selection of an appropriate study population and end point, the corresponding expected event rate, estimates of loss to followup, and death and compliance rates. If a preventive agent has an impact on the ability to detect prostate cancer, additional study design considerations are then made. Other practical issues are addressed, including collection of biological materials for correlative studies, assessment of quality of life measures and the addition of ancillary studies that may include the collection of additional end points unrelated to prostate cancer. RESULTS: The Southwest Oncology Group is coordinating 2 recently reported phase III prostate cancer prevention trials. The Prostate Cancer Prevention Trial final results of 18,882 men randomized to either finasteride or placebo, and the Selenium and Vitamin E Cancer Prevention Trial has accrued more than half of its goal of 32,400 men. These studies are used to illustrate some statistical design features. CONCLUSIONS: The aforementioned trials provide valuable lessons in the successful design and conduct of phase III prostate cancer prevention trials.

Anticarcinogenic Agents↗

Mutant DNA in plasma of lung cancer patients: potential for monitoring response to therapy.

The hypothesis tested was that mutant tumor DNA shed into plasma would show predictive value for monitoring response to therapy in non-small cell lung carcinoma patients. Pretreatment plasma specimens from 25 patients on a phase I trial were evaluated, 12 with paired posttreatment specimens, and 138 patients on the Southwest Oncology Group S0003 trial, 38 with paired posttreatment specimens, for the presence of K-RAS mutations. Thirteen tumor specimens from the phase I trial patients and seven tumor specimens from S0003 patients were also available for comparative analysis of K-RAS mutations in tumor tissue and plasma. All patients were treated similarly with paclitaxel, and carboplatin chemotherapy. DNA was extracted and mutational analyses performed using an RFLP-PCR assay. K-RAS mutations were found in plasma DNA in 5/25 of the phase I patients (20%). Median survival was 10 months in all patients, 11.4 months in the wild-type K-RAS group, and 3.3 months in the mutant K-RAS group (P = 0.056). Point mutations in plasma DNA were identical to mutations found in the tumors, confirming the tumor as the source. In two patients with K-RAS mutations pretreatment, posttreatment plasmas were evaluated: a patient with clinical progressive disease retained the mutant DNA, while in a patient with a complete response (CR), the K-RAS mutation was no longer detectable. In an ongoing analysis of S0003 patients, to date, K-RAS mutations have been found in the plasma of 14 patients (10.1%). In 42 matched pre- and posttreatment specimens from both phase I and S0003 trials, four patients had K-RAS mutations pretreatment that were not detectable posttreatment. Of these, two had a clinical CR or partial response, and the other two had stable disease. It was concluded that detection of tumor DNA in plasma is feasible using molecular techniques and that this approach shows promise for monitoring patient response to therapy.

Antineoplastic Agents↗

Estimating the impact of new clinical trial proven cancer therapy and cancer chemoprevention on population mortality: the Karnofsky Memorial lecture.

PURPOSE: The 31-year "war on cancer" has focused largely on therapeutic (as opposed to preventative) cancer research, which, in both the public and private sector, has received the majority of funding. Meanwhile the prevention of cancer has received less attention. PATIENTS AND METHODS: We analyzed eight positive phase III therapeutic trials of the Southwest Oncology Group, and estimated how the observed improvements in survival from the new therapies would impact mortality at the population level (utilizing Surveillance, Epidemiology, and End Results-data). We compared these results with the impact of the Prostate Cancer Prevention Trial. The measure of impact was person-years saved in the first 5 years. RESULTS: Estimates of person-years saved in the first 5 years included 28,534 from improved treatment of localized bladder cancer and 26,241 from improved treatment of advanced lung cancer, representing, respectively, 31.4% and 2.8% of the person-years which could have been saved for these diseases (the "relative impact of new treatment on survival"). The new therapies from all eight positive phase III trials would have saved 114,641 person-years over the first 5 years. The estimate from the Prostate Cancer Prevention Trial was 99,441 person-years over the first 5 years. CONCLUSION: New cancer therapies have a proven and quantifiable impact on population mortality. Successful cancer prevention has a similarly large impact. However, federal funding for cancer prevention is less than half that of cancer treatment. As a result of its enormous potential for extending life, cancer prevention warrants increased funding and support from federal funding agencies.

Antineoplastic Agents↗

The influence of finasteride on the development of prostate cancer.

BACKGROUND: Androgens are involved in the development of prostate cancer. Finasteride, an inhibitor of 5alpha-reductase, inhibits the conversion of testosterone to dihydrotestosterone, the primary androgen in the prostate, and may reduce the risk of prostate cancer. METHODS: In the Prostate Cancer Prevention Trial, we randomly assigned 18,882 men 55 years of age or older with a normal digital rectal examination and a prostate-specific antigen (PSA) level of 3.0 ng per milliliter or lower to treatment with finasteride (5 mg per day) or placebo for seven years. Prostate biopsy was recommended if the annual PSA level, adjusted for the effect of finasteride, exceeded 4.0 ng per milliliter or if the digital rectal examination was abnormal. It was anticipated that 60 percent of participants would have prostate cancer diagnosed during the study or would undergo biopsy at the end of the study. The primary end point was the prevalence of prostate cancer during the seven years of the study. RESULTS: Prostate cancer was detected in 803 of the 4368 men in the finasteride group who had data for the final analysis (18.4 percent) and 1147 of the 4692 men in the placebo group who had such data (24.4 percent), for a 24.8 percent reduction in prevalence over the seven-year period (95 percent confidence interval, 18.6 to 30.6 percent; P<0.001). Tumors of Gleason grade 7, 8, 9, or 10 were more common in the finasteride group (280 of 757 tumors [37.0 percent], or 6.4 percent of the 4368 men included in the final analysis) than in the placebo group (237 of 1068 tumors [22.2 percent], P<0.001 for the comparison between groups; or 5.1 percent of the 4692 men included in the final analysis, P=0.005 for the comparison between groups). Sexual side effects were more common in finasteride-treated men, whereas urinary symptoms were more common in men receiving placebo. CONCLUSIONS: Finasteride prevents or delays the appearance of prostate cancer, but this possible benefit and a reduced risk of urinary problems must be weighed against sexual side effects and the increased risk of high-grade prostate cancer.

5-alpha Reductase Inhibitors↗

A new staging system for multiple myeloma patients based on the Southwest Oncology Group (SWOG) experience.

We aimed to develop and evaluate a staging system for multiple myeloma (MM) based on easily obtained laboratory measures. The Durie-Salmon stage is most commonly used and is an effective system of patient stratification for clinical trial research. However, the criteria are complex and many laboratory parameters are required to properly stage patients. In this analysis, we focused on two common measures with prognostic importance in MM: serum beta2 microglobulin (beta2m) and serum albumin. Pre-study data on 1555 previously untreated MM patients enrolled on four recent South-west Oncology Group (SWOG) phase III trials were used in the analysis. Staging models were developed and validated using regression tree methods for survival outcomes. SWOG stages were defined as: stage 1, beta2m < 2.5 mg/l (14% of patients, median overall survival of 55 months); stage 2, 2.5 </= beta2m < 5.5 (43% of patients, median overall survival of 40 months); stage 3, beta2m >/= 5.5 and albumin >/= 30 g/l (32% of patients, median overall survival of 24 months); and stage 4, beta2m >/= 5.5 and albumin < 30 g/l (11% of patients and median overall survival of 16 months). This staging scheme was also predictive of event-free survival, first-year mortality and long-term (>/= 5 years) event-free survival. We conclude that although the SWOG stage does not represent a new prognostic marker for MM (cytogenetics, FISH), it could provide a simple alternative to the Durie-Salmon stage for patients with previously untreated MM. Additional evaluation in other MM patient populations is needed to confirm results.

Adult↗

Vascular access.

Vascular access is the cornerstone of medical therapy in the pediatric population and presents unique challenges. The vessels are small, often exceedingly so, and gaining access may require considerable patience and skill. Peripheral IVs are difficult to place in children, both because of lack of patient cooperation and because of the very small size of many veins. In addition, repeated venipuncture has been identified as one of the greatest stresses in hospitalized children. In the recent past, all forms of central venous access were the preserve of surgeons and were placed in the operating room under general anesthesia. In recent years, pediatric interventional radiologists have described placing peripherally inserted central catheters (PICCs), subcutaneous venous access ports, hemodialysis catheters, and a variety of temporary and permanent central lines even in the smallest children. This has been achieved safely, reliably, and, by dispensing with general anesthesia and operating room time in most cases, at considerable cost savings to the entire health care system. In addition, new forms of reliable, stable access such as the PICC line have made possible outpatient treatment of a wide variety of conditions, particularly infectious, which previously necessitated hospital admission. This has resulted not only in considerable cost saving for the health care system but also improved quality of life for the patient and their family. In this section, I review the current state of pediatric vascular access with emphasis on those areas where pediatric differs from adult practice.

Adolescent↗

Prognostic factors and response to fludarabine therapy in Waldenstrom's macroglobulinemia: an update of a US intergroup trial (SW0G S9003).

We report an update on a prospective observational trial for Waldenstrom's macroglobulinemia (WM) that called for re-registration to treatment with fludarabine (30 mg/m(2)) upon the development of symptomatic or progressive disease. Patients who did not require therapy for more than 1 year (n = 54) could be distinguished from the 118 untreated patients requiring immediate therapy on the basis of hemoglobin, serum beta(2)-microglobulin (beta2m), C-reactive protein (CRP), albumin, and IgM levels, and lower incidence of extramedullary infiltration. Overall response rate (>or= partial response [PR]) to fludarabine was 38%, with 2% complete remissions (CRs). Event-free and overall survivals were significantly longer in the presence of lower levels of serum beta2m in all cohorts. Using time-dependent covariates, neither the occurrence of response (>or= PR) nor the time to response was associated with superior overall or event-free survival. These data support serum beta2m as the dominant prognostic indicator in WM, and show that this factor alone can provide valuable disease risk assessment. Response to therapy using current criteria is not a reliable predictor for survival in this disease.

Antineoplastic Agents↗