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Yi-Ching Hsieh

Publications and source records attributed to Yi-Ching Hsieh.

16 recordsLinked to original sources
PubMed2006

Classification and regression tree analysis for the prediction of aggressive prostate cancer on biopsy.

PURPOSE: Prostate cancer screening allows early cancer detection but not all patients benefit from subsequent therapy. Thus, identifying patients who are likely to harbor aggressive cancer could significantly decrease the number of prostate biopsies performed. MATERIALS AND METHODS: Data were collected on 1,563 consecutive referred men with serum PSA 10 ng/ml or less who underwent an initial prostate biopsy. Predictors of aggressive cancer (Gleason sum 7 or greater) were identified using CART analysis. Model building was done in a randomly selected training set (70% of the data) and validation was completed using the remaining data. RESULTS: Cancer was detected in 406 men (26.1%). Gleason 7 or greater cancer was found in 130 men (8.3%). CART created a decision tree that identified certain groups at risk for aggressive cancer, namely 1) PSAD greater than 0.165 ng/ml/cc, and 2) PSAD greater than 0.058 to 0.165 ng/ml/cc or less, age greater than 57.5 years and prostate volume greater than 22.7 cc. The incidence of aggressive prostate cancer was 1.1% when PSAD was 0.058 ng/ml/cc or less in the validation set. The sensitivity and specificity of CART for identifying men with aggressive cancer were 100% and 31.8% for model building data, and 91.5% and 33.5% for the validation data set, respectively. CONCLUSIONS: CART identified groups at risk for aggressive prostate cancer. Application of this CART could decrease unnecessary biopsies by 33.5% when only a diagnosis of high grade prostate cancer would lead to subsequent therapy.

Aged↗
PubMed2005

Acute hemodynamic effects of pacing in patients with Fontan physiology: a prospective study.

OBJECTIVES: The purpose of this research was to assess the hemodynamic response to atrial, ventricular, and dual-chamber pacing in patients with Fontan physiology. BACKGROUND: Bradycardia, due to sinus node dysfunction or atrioventricular (AV) block, with need for pacing, is common after the Fontan operation. The optimal pacing mode for Fontan patients is unknown, but is critical, as hemodynamic aberrancies may cause severe clinical deterioration. We hypothesized that AV synchrony is vital for maximizing Fontan hemodynamics. METHODS: A cross-over trial was conducted with 21 patients (age 2 to 18 years, median 4 years; male patients = 13) in the intensive care unit after a Fontan operation. Hemodynamic parameters, including mean left atrial pressure (LAP, in mm Hg), mean pulmonary artery pressure (PAP, in mm Hg), mean arterial blood pressure (MAP, in mm Hg), and indexed cardiac output via Fick (Qs, in l/min/m2) were measured with atrial, ventricular, and dual-chamber pacing. Measurements were made after pacing for 10 min in each mode, and a 10-min rest was given between each pacing maneuver. RESULTS: Asynchronous ventricular (VOO) pacing resulted in significantly worse hemodynamics when compared to dual-chamber (DOO) and atrial (AOO) pacing with a higher LAP (9.4 VOO; 6.8 DOO; 5.4 AOO) and PAP (15.2 VOO; 13.5 DOO; 12.7 AOO) and lower Qs (3.0 VOO; 3.5 DOO; 3.9 AOO) and MAP (60.1 VOO; 66.5 DOO; 67.2 AOO). CONCLUSIONS: Asynchronous ventricular pacing, after the Fontan procedure, has acute, adverse hemodynamic consequences (elevated LAP and PAP and decreased Qs and MAP).

Adolescent↗
PubMed2005

Improved detection of prostate cancer using classification and regression tree analysis.

PURPOSE: To build a decision tree for patients suspected of having prostate cancer using classification and regression tree (CART) analysis. PATIENTS AND METHODS: Data were uniformly collected on 1,433 referred men with a serum prostate-specific antigen (PSA) levels of < or = 10 ng/mL who underwent a prostate biopsy. Factors analyzed included demographic, laboratory, and ultrasound data (ie, hypoechoic lesions and PSA density [PSAD]). Twenty percent of the data was randomly selected and reserved for study validation. CART analysis was performed in two steps, initially using PSA and digital rectal examination (DRE) alone and subsequently using the remaining variables. RESULTS: CART analysis selected a PSA cutoff of more than 1.55 ng/mL for further work-up, regardless of DRE findings. CART then selected the following subgroups at risk for a positive biopsy: (1) PSAD more than 0.165 ng/mL/cc; (2) PSAD < or = 0.165 ng/mL/cc and a hypoechoic lesion; (3) PSAD < or = 0.165 ng/mL/cc, no hypoechoic lesions, age older than 55.5 years, and prostate volume < or = 44.0 cc; and (4) PSAD < or = 0.165 ng/mL/cc, no hypoechoic lesions, age older than 55.5 years, and 50.25 cc less than prostate volume < or = 80.8 cc. In the validation data set, specificity and sensitivity were 31.3% and 96.6%, respectively. Cancers that were missed by the CART were Gleason score 6 or less in 93.4% of cases. Receiver operator characteristic curve analysis showed that CART and logistic regression models had similar accuracy (area under the curve = 0.74 v 0.72, respectively). CONCLUSION: Application of CART analysis to the prostate biopsy decision results in a significant reduction in unnecessary biopsies while retaining a high degree of sensitivity when compared with the standard of performing a biopsy of all patients with an abnormal PSA or DRE.

Adult↗
PubMed2005

Treatment of erectile dysfunction following therapy for clinically localized prostate cancer: patient reported use and outcomes from the Surveillance, Epidemiology, and End Results Prostate Cancer Outcomes Study.

PURPOSE: Erectile dysfunction (ED) persists for years following curative therapies for clinically localized prostate cancer. We report use and treatment outcomes in a 5-year interval in a population based cohort from the Surveillance, Epidemiology, and End Results Prostate Cancer Outcomes Study. MATERIALS AND METHODS: A sample of 1,977 men with localized prostate cancer who received external beam radiation therapy or radical prostatectomy in 1994 to 1995 were surveyed for 5 outcome measures of ED treatment, namely treatment, perceived helpfulness, erectile sufficiency, sexual activity frequency and erection maintenance. Subjects were surveyed 6, 12, 24 and 60 months after prostate cancer diagnosis. RESULTS: Overall 50.5% of men ever used ED treatment. The use of ED treatments increased during the study course. Subject age, regular sexual partner and baseline sexual activity were factors positively associated with ED treatments. While it was used uncommonly (1.9%), a penile prosthesis was perceived as the most helpful ED treatment (helped a lot in 52% of respondents). Sildenafil helped a lot in 12% of respondents. Erectile fullness, erection maintenance and sexual activity frequency were modestly improved in men using ED treatment compared with those in men not using ED treatment. CONCLUSIONS: Approximately half of the patients in this population based cohort of men used ED treatment during the 5 years following prostate cancer diagnosis. Men using ED treatments had modest improvement in sexual function compared with men that in who did not receive ED treatment at 60 months. More effective treatments for ED following local therapy for prostate cancer are needed.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed2005

In chronic myeloid leukemia white cells from cytogenetic responders and non-responders to imatinib have very similar gene expression signatures.

BACKGROUND AND OBJECTIVES: Imatinib induces complete cytogenetic responses (CCR) in the majority of patients with chronic myeloid leukemia (CML) in chronic phase (CP). However, a subgroup of patients is refractory at the cytogenetic level. Clinically, it would be advantageous to identify such patients a priori, since they may benefit from more aggressive therapy. DESIGN AND METHODS: To elucidate mechanisms underlying cytogenetic refractoriness, we used Affymetrix oligonucleotide arrays to determine the transcriptional signature associated with cytogenetic refractoriness in unselected white blood or bone marrow cells from 29 patients with CML in first CP prior to treatment with imatinib. Patients with CCR within 9 months were defined as responders (n = 16) and patients lacking a major cytogenetic response (> 35% Philadelphia-positive metaphases) after 1 year were defined as non-responders (n = 13). RESULTS: Differences in gene expression between responders and non-responders were subtle. Stringent statistical analysis with multiple comparison adjustments revealed very few differentially expressed genes. Differentially expressed genes could not be confirmed in an independent test set. INTERPRETATION AND CONCLUSIONS: We conclude that transcriptional profiling of unselected white cells is of limited value for identifying genes consistently associated with cytogenetic refractoriness to imatinib.

Adult↗
PubMed2004

How accurate is clinician reporting of chemotherapy adverse effects? A comparison with patient-reported symptoms from the Quality-of-Life Questionnaire C30.

PURPOSE: Adverse events in chemotherapy clinical trials are assessed and reported by clinicians, yet clinician accuracy in assessing symptoms has been questioned. We compared patient reporting of eight symptoms using a validated instrument, the European Organization for the Research and Treatment of Cancer Quality-of-Life Questionnaire C30 (QLQ-C30 or QLQ) with physicians' reporting of the same symptoms in the study's adverse events log. PATIENTS AND METHODS: Thirty-seven men with metastatic, androgen-independent prostate cancer enrolled onto a phase II trial of weekly calcitriol and docetaxel completed the QLQ every 4 weeks for up to 28 weeks. A patient-reported symptom was defined as an increase in a QLQ symptom score by at least 10 points (0 to 100 scale), sustained for at least 4 weeks. A physician-reported symptom was considered present if it was ever documented in the adverse event log. RESULTS: Forty-nine (new or worsened) symptoms were detected by both physician and QLQ, 48 symptoms were detected by the physician alone, and 55 symptoms were detected by the QLQ alone. They agreed on the absence of a symptom in 102 instances of 254 possible opportunities. Their uncorrected agreement was 59.4%, but Cohen's kappa, a coefficient of agreement that corrects for chance, was 0.15, indicating only slight agreement. Using the QLQ as the standard, overall physician sensitivity and specificity was 47% and 68%, respectively, although it varied considerably among symptoms. CONCLUSION: Even in a tightly controlled clinical trial, physician reporting was neither sensitive nor specific in detecting common chemotherapy adverse effects. Tools for collecting patient-reported adverse event data in chemotherapy clinical trials should be developed.

Adverse Drug Reaction Reporting Systems↗
PubMed2004

Quality of life and pain relief during treatment with calcitriol and docetaxel in symptomatic metastatic androgen-independent prostate carcinoma.

BACKGROUND: The current study evaluated the analgesic activity and impact on quality of life (QOL) of a new chemotherapy regimen of calcitriol and docetaxel in men with androgen-independent prostate carcinoma. METHODS: Analgesic response was defined as a 2-point reduction on the Present Pain Intensity (PPI) scale (or compete relief if baseline PPI was 1) without an increase in analgesic use or a 50% decrease in analgesic medication use without an increase in pain, maintained for > or = 4 weeks. Pain, pain medication consumption, and QOL (measured by the European Organization for Research and Treatment of Cancer QLQ-C30) were evaluated every 4 weeks. RESULTS: Treatment resulted in an analgesic response in 14 of 29 evaluable patients (48%; 95% confidence interval [95% CI], 30-67%). The median time to symptomatic progression in the 14 patients who met criteria for analgesic response was 41 weeks (95% CI, 26-56 weeks). Worsening in physical and role functioning, fatigue, appetite, and global health status and improvement in constipation were detected using the QLQ-C30 QOL questionnaire. CONCLUSIONS: Significant analgesic activity was demonstrated, although worsening in several QOL domains was observed in a patient population with relatively low pain intensity (median PPI, 2).

Adenocarcinoma↗
PubMed2004

Residual urine in an elderly female population: novel implications for oral estrogen replacement and impact on recurrent urinary tract infection.

PURPOSE: While the distribution of post-void residual urine volume (PVR) has been well studied in men, scant literature is available concerning PVR in women. We characterized any relationship between PVR and urinary tract infection (UTI). We also characterized other factors that could impact bladder emptying, including oral estrogen replacement therapy. MATERIALS AND METHODS: Inclusion criteria were at least 2 clinic visits and no antimicrobial prophylaxis in the last year. Women with a history of diabetes or cystocele were excluded. In a 17-month period 204 women met inclusion criteria. PVR was measured by catheterized specimen. Patients were categorized into groups by UTI history, namely 94 of those with no UTIs in the last year (group 1) and 110 with 1 or more documented UTIs in the last year (group 2). Factors that could affect bladder emptying were tested for the impact on PVR. RESULTS: Mean PVR in the study group was 53.13 ml. The mean PVR in groups 1 and 2 was 33 and 70.25 ml, respectively. The difference between these 2 groups was significant (p <0.0001). Estrogen status data were available on 186 patients. The 62 patients on estrogen replacement therapy had a mean PVR of 39.33 ml. The 124 patients not on estrogen replacement therapy had a mean PVR of 66.67 ml. The difference between these 2 groups was significant (p = 0.002) and independent of UTI history. CONCLUSIONS: Of elderly women those with high PVR were more likely to have recurrent UTIs. Improved bladder function was documented in women receiving oral estrogen replacement therapy.

Age Factors↗
PubMed2004

Predictors of delayed therapy after expectant management for localized prostate cancer in the era of prostate-specific antigen.

OBJECTIVE: To identify risk factors for delayed cancer-directed intervention in modern era prostate cancer patients who initially elect expectant management. MATERIALS AND METHODS: An observational, cohort study of expectantly managed patients, diagnosed with clinical T(1-4)NxM0 prostate cancer between 1993 and 2000 was carried out. Data including TNM stage, age, serum prostate-specific antigen (PSA), prostate gland volume by transrectal ultrasound, Gleason score, percent biopsies positive for cancer, imaging results, initial treatment selection, and outcome data were collected on all patients. RESULTS: 192 of 561 patients (34.3%) elected expectant management, and follow-up data were available for 187 (97.4%) patients. With a median follow-up of 3.6 years, 90 (48.1%) patients had a cancer-directed intervention. Gleason score (p = 0.0097) and percent of positive biopsy cores (p = 0.03) were independent predictors of time to intervention. As expected, PSA doubling time became the most significant predictor of intervention (p = 0.0057) when added to the model. These independent covariates are able to characterize low-, intermediate- and high-risk groups for cancer-directed intervention. CONCLUSIONS: Cancer-directed intervention is common in patients who choose expectant management in the PSA era. Gleason score and percent of positive biopsy cores predict cancer-directed interventions, thus, these patients may be least suitable for expectant management.

Adenocarcinoma↗
PubMed2003

Predictive modeling for the presence of prostate carcinoma using clinical, laboratory, and ultrasound parameters in patients with prostate specific antigen levels < or = 10 ng/mL.

BACKGROUND: The objective of the current study was to develop a model for predicting the presence of prostate carcinoma using clinical, laboratory, and transrectal ultrasound (TRUS) data. METHODS: Data were collected on 1237 referred men with serum prostate specific antigen (PSA) levels < or = 10 ng/mL who underwent an initial prostate biopsy. Variables analyzed included age, race, family history, referral indication(s), prior vasectomy, digital rectal examination (DRE), PSA level, PSA density (PSAD), and TRUS findings. Twenty percent of the data were reserved randomly for study validation. Logistic regression analysis was performed to estimate the relative risk, 95% confidence interval, and P values. RESULTS: Independent predictors of a positive biopsy result included elevated PSAD, abnormal DRE, hypoechoic TRUS finding, and age 75 years or older. Based on these variables, a predictive nomogram was developed. The sensitivity and specificity of the model were 92% and 24%, respectively, in the validation study for which the predictive probability > or = 10% was used to indicate the presence of prostate carcinoma. The area under the receiver operating characteristic curve (AUC) for the model was 73%, which was significantly higher compared with the prediction based on PSA alone (AUC, 62%). If it was validated externally, then application of this model to the biopsy decision could result in a 24% reduction in unnecessary biopsy procedures, with an overall reduction of 20%. CONCLUSIONS: Incorporation of clinical, laboratory, and TRUS data into a prebiopsy nomogram significantly improved the prediction of prostate carcinoma over the use of individual factors alone. Predictive nomograms may serve as an aid to patient counseling regarding prostate biopsy outcome and to reduce the number of unnecessary biopsy procedures.

Adenocarcinoma↗
PubMed2003

Clonal evolution and lack of cytogenetic response are adverse prognostic factors for hematologic relapse of chronic phase CML patients treated with imatinib mesylate.

We followed 141 patients treated with imatinib mesylate (> 300 mg) for chronicphase chronic myelogenous leukemia (CML) following failure of treatment with interferon. During 12 months from the start of imatinib mesylate treatment, 96.5% achieved a complete hematologic response, 47.0% achieved a major cytogenetic response, and 32.4% achieved a complete cytogenetic response. The proportion of patients with hematologic relapse was 10.9% at 12 months and 14.6% at 18 months. In a univariate Cox regression analysis, the only pretreatment characteristics that correlated with an increased risk of hematologic relapse were hemoglobin level less than 120 g/L (12 g/dL) (P =.02), increased bands in the peripheral blood (P =.01), and clonal evolution (P <.0001). In a multivariate analysis, an elevated platelet count (P =.03) and clonal evolution (P <.0001) were the only significant factors for hematologic relapse. During treatment, the absence of a major cytogenetic response within the first 6 months also significantly correlated with relapse (P =.03). Notably, patients failing to achieve a major cytogenetic response by 6 months had a significantly higher rate of hematologic relapse (27%) compared with those who achieved a major cytogenetic response by 6 months (3%), and patients with clonal evolution had a significantly higher risk of hematologic relapse (50%) than those without clonal evolution (9%).

Adult↗
PubMed2003

Tanning facility use: are we exceeding Food and Drug Administration limits?

BACKGROUND: The US Food and Drug Administration (FDA) recommends exposure limits for tanning bed use. Tanning patrons may not be following these recommendations and may be overexposed to damaging ultraviolet radiation (UV). OBJECTIVE: This study was conducted to assess tanning patrons' adherence to FDA-recommended exposure limits and to measure the amount of UVA and UVB radiation emitted by tanning beds. METHODS: A community-based survey was administered during routine state inspections of North Carolina tanning facilities (n = 50). At each facility, patron records were randomly selected (n = 483) for a survey of exposure records, and UVA and UVB outputs were measured for each tanning bed. RESULTS: The recommended limits were exceeded by 95% of patrons, and 33% of patrons began tanning at the maximum doses recommended for maintenance tanning. Average tanning bed output was 192.1 W/m(2) UVA and 0.35 W/m(2) erythemally weighted UVB. CONCLUSIONS: Interventions for tanning bed operators and patrons are needed to increase compliance with federally recommended exposure limits.

Beauty Culture↗
PubMed2002

Factors that influence surgical choices in women with breast carcinoma.

BACKGROUND: In the absence of medical contraindications, survival after undergoing breast-conserving therapy (BCT), mastectomy (M), and mastectomy with immediate reconstruction (MIR) is equal. The authors studied demographic factors to identify the variables that differed significantly among women making different surgical choices. METHODS: Women with ductal carcinoma in situ or clinical Stage I or II breast carcinoma with no contraindications for BCT or MIR who were treated between 1995 and 1998 were identified from a prospectively collected data base. Demographic and tumor factors were compared using the Fisher exact test. RESULTS: There were 578 women with 586 tumors who did not have contraindications for BCT or MIR. Among this group, 85.2% of women chose BCT, 9.2% of women chose M, and 5.6% of women chose MIR. Women undergoing M alone were older and were more likely to have Stage II carcinoma compared with women undergoing BCT. Patients undergoing M or MIR were more likely to have had a prior breast biopsy compared with patients who chose BCT. Marital status and employment approached significance (P = 0.06); however, a family history of breast carcinoma was not a predictor of treatment choice. CONCLUSIONS: The current findings suggest a need for patient education strategies that emphasize the lack of influence of age and prior breast biopsy on the use of BCT. Differences in demographic variables may reflect true variations in patient preference among groups, emphasizing the need to address the spectrum of treatment options with patients.

Age Factors↗
PubMed2002

Phase I trial of oral estramustine and 3-hr infusional paclitaxel for the treatment of hormone refractory prostate cancer.

PRECIS: Estramustine 600 mg/m2 can be administered safely with 225 mg/m2 of paclitaxel if administered as a 3-hr infusion for the treatment of hormone refractory prostate cancer. Significant anti-tumor activity has been reconfirmed despite the change in schedule of administration of the paclitaxel. PURPOSE: This phase I study was conducted to identify the maximum tolerated dosage of paclitaxel administered as a 3-hr infusion combined with a stable dosage of estramustine capsules daily in men with hormone refractory prostate cancer. A secondary endpoint was to assess anti-tumor efficacy in this targeted patient population. PATIENTS AND METHODS: Twenty-six male patients, all with hormone refractory prostate cancer were enrolled in this trial. Estramustine was administered at a dosage of 600 mg/m2 daily, and paclitaxel was dose-escalated in cohorts from 125 to 250 mg/m2 administered as an infusion over 3 hr every 21 days. Patients were treated until maximum response was achieved, or toxicity or progressive disease precluded further treatment. Toxicity to determine maximum tolerated dose was assessed only during the first 3-week cycle. RESULTS: The maximum tolerated dose of paclitaxel on this schedule was 225 mg/m2 based on unacceptable dose-limiting fatigue observed at the next higher dosage level. Other grade 3 or 4 events included myelosuppression, left ventricular dysfunction, elevated liver function tests, deep venous thrombosis, vomiting, and development of depression. Using a response criteria of prostate specific antigen decline of > 50% persisting for a minimum of 6 weeks, eight of 26 patients responded (30.8%). Two of seven patients with documented soft-tissue disease experienced > 50% reductions in size of lesions or number of sites. The median response duration was 6 months, and the median survival time was 16 months. CONCLUSION: The recommended phase II dose of paclitaxel is 225 mg/m2 when administered over 3 hr in combination with estramustine. This regimen has an acceptable toxicity profile, is a convenient schedule, and results in significant antitumor activity even in a heavily pre-treated population of patients.

Administration, Oral↗
PubMedDate not supplied

Using enzyme immunoassay to detect Helicobacter pylori stool antigen for investigating the prevalence of Helicobacter pylori infection in children and adolescents in Changhua.

To investigate the prevalence of Helicobacter pylori (H. pylori) infection in adolescents and children in Changhua and to compare the differences between urban and rural areas, we used enzyme immunoassay to detect H. pylori stool antigen for feco-prevalence study. In addition, a questionnaire was designed to obtain demographic and clinical information. Children and adolescents under 18 years of age living in Changhua city and Yung-Chin village were divided into 6 groups respectively, ie. 0-3, 3-6, 6-9, 9-12, 12-15, and 15-18 years. A minimum of 30 persons were investigated in each group. A total of 567 subjects (M/F 295/272) were included in this study. There was no significant difference in H. pylori infection with regard to residential area, gender, education of the mother, occupation of parents, family history of peptic ulcer, and number of family members, except for epigastralgia of the subjects (p=0.001) and education of the father (p=0.039). The overall prevalence was 13.75%. A low prevalence was noted in the group 0-3 years (2.0%). The prevalence increased with age and reached its maximum of 23.8% in the age group of 9-12 years and then declined. The multiple logistic regression analysis revealed that only age (odds ratio (OR)=1.3, 95% confidence interval (C.I.)=1.1-1.5) and epigastralgia (OR=1.71, 95% C.I.=1.0-3.0) were the most important risk factors for H. pylori infection after adjusting for participating gender, place of residence and father's age. The difference in age pattern of H. pylori infection between our results and other studies needs further investigation.

Adolescent↗