Prostate specific antigen isoforms and human glandular kallikrein 2--which offers the best screening performance in a predominantly black population?

PURPOSE: Free prostate specific antigen, complexed PSA and human glandular kallikrein 2 have independently been tested against the gold standard of total PSA for prostate cancer screening in largely white populations. With the incidence of prostate cancer much higher in black men, we sought to evaluate these markers simultaneously in a predominantly black population. MATERIALS AND METHODS: A total of 138 men, of whom 108 were black, underwent ultrasound guided biopsy of the prostate for tPSA levels greater than 2.5 ng/ml or an abnormal digital rectal examination. Sera were drawn before biopsy and analyzed for tPSA, fPSA, cPSA and hK2 concentrations using standard methods (hK2 assay is for research use only, not for use in diagnostic procedures). The areas under the receiver operator characteristic curves were determined for each marker as well as biomarker combinations. Additionally, each parameter's specificity, positive and negative predictive values, and theoretical screening efficiency were assessed at or above the 95% sensitivity level. RESULTS: A total of 43 (31.1%) men had prostate cancer by biopsy. While the AUC for %fPSA was statistically the highest (0.822, p <0.001), cPSA offered the highest specificity (31.6%) and positive predictive power (31.7%) of any of the tested biomarkers at comparable sensitivity (greater than 95%). The calculated efficiency of cPSA (51.4%) was also higher than the other markers. Nearly 20% of biopsies would be avoided using cPSA vs standard tPSA screening methods. CONCLUSIONS: Comparing the major PSA isoforms and hK2, cPSA alone appears to offer superior diagnostic discrimination for cancer detection in a predominantly black population.

Early detection of prostate cancer in African-American men through use of multiple biomarkers: human kallikrein 2 (hK2), prostate-specific antigen (PSA), and free PSA (fPSA).

Recent studies have reported enhanced prostate cancer detection in Caucasians with serum human glandular kallikrein 2 (hK2) in combination with total- (tPSA) and free-prostate-specific antigen (fPSA). The purpose of this study is to validate these findings in an African-American patient cohort. A total of 137 African-American men were found by routine screening to have tPSA levels above 2.5 ng/ml or an abnormal digital rectal examination. Sera were drawn prior to biopsy of the prostate and Hybritech PSA, FPSA and hK2 (for research use only, not for use in diagnostic procedures) concentrations were determined on Beckman Coulter's Access immunoanalyzer. These independent variables and the ratios of percent fPSA (%fPSA), hK2/tPSA, hK2/fPSA, and hK2*tPSA/fPSA were compared between cancer and non-cancer groups. In all, 49 of 137 men had prostate cancer. hK2 and its calculated ratios outperformed tPSA on receiver operator characteristic (ROC) analysis, but %fPSA had statistically the highest area under the curve (AUC) at 0.801. When restricting the analysis to only the tPSA range of 4.0-10 ng/ml, hK2/fPSA yielded the highest AUC (0.721). The ratio of hK2/fPSA was also found to increase the positive predictive value (PPV) of the %fPSA ranges less than 10 and 10-25%. %fPSA offered the best performance and highest specificity in prostate cancer detection in African-American males over the entire range of tPSA. hK2/fPSA may offer modest improvement in the tPSA range of 4.0-10 ng/ml. Furthermore, hK2/fPSA can enhance the PPV of low %fPSA values. Therefore, the use of multiple biomarkers may ultimately increase the specificity of prostate cancer screening in African-American men.

Complexed PSA performance for prostate cancer detection in an African-American population.

OBJECTIVES: Complexed prostate-specific antigen (cPSA) has been shown to improve the differentiation of benign and malignant disease compared with total PSA (tPSA) in studies evaluating predominantly white populations of men. We sought to evaluate the diagnostic performance of cPSA relative to tPSA in a population of African-American men. METHODS: Consecutive African-American men scheduled for prostate biopsy were enrolled prospectively at the Louisiana State University Medical Center, New Orleans. Serum was collected before the biopsy procedure and tested with the Immuno 1 tPSA and cPSA methods. Receiver operating characteristic curve analysis was performed and the area under the curve was calculated for tPSA and cPSA. RESULTS: A total of 156 patients were evaluated, 51 (32.7%) of whom were diagnosed with prostate cancer. The median PSA value for men with prostate cancer was 4.96 ng/mL and for those with benign disease was 3.93 ng/mL. The receiver operating characteristic analysis indicated that the area under the curve for cPSA (0.679) was statistically greater than that achieved for tPSA (0.642, P = 0.004). Using cutoff values for cPSA of 2.3 ng/mL and for tPSA of 2.85 ng/mL provided a specificity of 31.4% and 26.7%, respectively, at a sensitivity for prostate cancer detection of 95%. This was not statistically significant (P = 0.18). CONCLUSIONS: cPSA offers modest improvement in prostate cancer detection compared with tPSA in African-American men, but not at the clinically relevant 95% sensitivity level. Additional work is needed to improve prostate cancer detection in this high-risk cohort of patients.

cPSA and fPSA elimination in African-American men.

In all, 22 African-American males undergoing radical prostatectomy for prostate adenocarcinoma had serum drawn for tPSA, cPSA, and total protein concentrations prior to, during, and after operation to determine the respective elimination rates. African-American cPSA was found to fit best a simple first-order exponential elimination kinetic, with a half-life of 44.6 h. fPSA followed a two-compartment elimination with an alpha-phase elimination of 0.50 h and a beta-phase half-life of 4.2 h. Our results suggest higher rates of elimination for both cPSA and fPSA in an African-American male population with respect to Caucasians and may account for differences in PSA values between races.

Cervical cancer screening knowledge, behaviors, and beliefs of Vietnamese women.

PURPOSE/OBJECTIVES: To describe the knowledge, beliefs, and practices of cervical cancer screening of Vietnamese women who have migrated to the United States. DESIGN: Exploratory, descriptive. SETTING: Five Vietnamese churches in southeastern Louisiana. SAMPLE: Nonprobability sample of 96 adult Vietnamese migrant women. METHODS: Data were collected by a bilingual nurse during face-to-face interviews conducted in the language preferred by the subjects (English or Vietnamese). MAIN RESEARCH VARIABLES: Cervical cancer screening knowledge, behaviors, and beliefs. FINDINGS: Three fourths of the Vietnamese women interviewed could not correctly explain what a Pap test is used for, and few were aware that the most commonly occurring cancer in Vietnamese females in the United States is cervical cancer. Most believed that their risk of cervical cancer was low. Less than half reported ever having had a Pap test and cited not having a gynecologist, cost, and fear of the test as reasons for not ever having had the test done. CONCLUSIONS: The number of Vietnamese women who adhere to cervical cancer screening guidelines is low. Cultural beliefs and structural barriers influence the choices that Vietnamese women make regarding Pap test utilization. IMPLICATIONS FOR NURSING PRACTICE: When planning programs to promote cervical cancer screening, nurses must target those at greatest risk--Vietnamese women. Culturally sensitive educational interventions and cervical cancer screening programs for Vietnamese women are needed to increase Pap test utilization and the early detection of cervical cancer.

Dose-ranging evaluation of the serotonin antagonist dolasetron mesylate in patients receiving high-dose cisplatin.

PURPOSE: This dose-ranging trial of intravenous dolasetron mesylate (MDL73,147EF) was performed to determine its adverse and antiemetic effects in patients receiving cisplatin at doses > or = 100 mg/m2. PATIENTS AND METHODS: Eighty-nine patients treated with initial cisplatin received a single intravenous dose of dolasetron mesylate administered over 20 minutes beginning 30 minutes before chemotherapy. The following four dose levels were studied: 1.8, 2.4, 3.0, and 5.0 mg/kg. Emesis and adverse effects were measured for 24 hours after cisplatin. RESULTS: All adverse effects were mild and transient including loose stools, headache, serum AST/ALT elevations, and asymptomatic prolongation of ECG intervals. Among the dose levels, no-emesis rates from 24% to 52% were observed, and the percentage of patients having zero, one, or two emetic episodes ranged from 48% to 82%. Complete control of vomiting increased as the dose was escalated to 2.4 mg/kg, but did not improve further with higher doses. CONCLUSION: Dolasetron mesylate can be administered safely at doses up to 5.0 mg/kg, with comparable complete protection rates and increased adverse effects at doses greater than 2.4 mg/kg. Antiemetic activity was seen after cisplatin. Trials comparing single infusions of dolasetron mesylate and ondansetron are under way.

A randomized clinical trial of two different durations of oral cryotherapy for prevention of 5-fluorouracil-related stomatitis.

BACKGROUND: The authors previously reported that 30 minutes of oral cryotherapy inhibits 5-fluorouracil (5-FU)-induced stomatitis. The current trial was designed to determine whether a longer duration of cryotherapy would provide additional protection. METHODS: This trial involved patients who were receiving their first course of a 5-FU plus leucovorin chemotherapy regimen, for which stomatitis is a major dose-limiting toxicity. These patients were randomized to receive either 30 or 60 minutes of oral cryotherapy given at around the same time as the 5-FU therapy. RESULTS: A total of 178 evaluable patients were studied. Both cryotherapy groups had similar degrees of mucositis. CONCLUSION: The authors continue to recommend the use of 30 minutes of oral cryotherapy for patients receiving bolus intensive courses of 5-FU-based chemotherapy.

Breast Cancer Prevention Trial update.

In April 1992, the National Surgical Adjuvant Breast and Bowel Project and the National Cancer Institute launched the Breast Cancer Prevention Trial. This is the largest cancer prevention trial ever attempted. The Breast Cancer Prevention Trial will involve 16,000 high-risk women in the United States and Canada. Half will receive tamoxifen and half placebo. Currently, over 5,000 women have been enrolled in the Breast Cancer Prevention Trial. The Ochsner Community Clinical Oncology Program in New Orleans is coordinating the trial in Louisiana and Mississippi. Other participating centers in this area are located in Baton Rouge, Houma, and New Orleans East in Louisiana, and Biloxi, Gulfport, Hattiesburg, and Jackson in Mississippi.