Do prostate cancer risk models improve the predictive accuracy of PSA screening? A meta-analysis.

BACKGROUND: Despite the extensive development of risk prediction models to aid patient decision-making on prostate screening, it is unknown whether these models could improve predictive accuracy of PSA testing to detect prostate cancer (PCa). The objective of this study was to perform a systematic review to identify PCa risk models and to assess the model's performance to predict PCa by conducting a meta-analysis. DESIGN: A systematic literature search of Medline was conducted to identify PCa predictive risk models that used at least two variables, of which one of the variables was prostate-specific antigen (PSA) level. Model performance (discrimination and calibration) was assessed. Prediction models validated in ≥5 study populations and reported area under the curve (AUC) for prediction of any or clinically significant PCa were eligible for meta-analysis. Summary AUC and 95% CIs were calculated using a random-effects model. RESULTS: The systematic review identified 127 unique PCa prediction models; however, only six models met study criteria for meta-analysis for predicting any PCa: Prostataclass, Finne, Karakiewcz, Prostate Cancer Prevention Trial (PCPT), Chun, and the European Randomized Study of Screening for Prostate Cancer Risk Calculator 3 (ERSPC RC3). Summary AUC estimates show that PCPT does not differ from PSA testing (0.66) despite performing better in studies validating both PSA and PCPT. Predictive accuracy to discriminate PCa increases with Finne (AUC = 0.74), Karakiewcz (AUC = 0.74), Chun (AUC = 0.76) and ERSPC RC3 and Prostataclass have the highest discriminative value (AUC = 0.79), which is equivalent to doubling the sensitivity of PSA testing (44% versus 21%) without loss of specificity. The discriminative accuracy of PCPT to detect clinically significant PCa was AUC = 0.71. Calibration measures of the models were poorly reported. CONCLUSIONS: Risk prediction models improve the predictive accuracy of PSA testing to detect PCa. Future developments in the use of PCa risk models should evaluate its clinical effectiveness in practice.

Prevalence of thrombocytopenia among patients with chronic hepatitis C: a systematic review.

Thrombocytopenia (TCP) is a haematological condition known to occur in chronically infected hepatitis C (HCV) patients and may interfere with diagnostic procedures, such as liver biopsy, because of risk of bleeding. It may also exclude patients from effective antiviral treatment. We conducted a systematic literature review of articles and conference abstracts, to assess the prevalence of TCP among those with HCV and to describe demographics, liver disease stage and treatment characteristics of these patients. Studies of individuals with confirmed chronic HCV infection were included in the review if the study had a clear definition of thrombocytopenia and a sample size of at least 50 subjects. The final selection included 27 studies (21 articles and six abstracts). The definitions of thrombocytopenia varied between studies and were based either on platelet counts, with threshold levels ranging between ≤ 100 × 10(9) and ≤ 180 × 10(9) /L, or on criteria set in haematological guidelines. The prevalence of TCP ranged from 0.16% to 45.4% and more than half of the studies reported a TCP prevalence of 24% or more. Because of the different TCP definitions, heterogeneity in study design and insufficient data on study characteristics such as age, gender, HCV treatment rates and disease severity an overall summary estimate of TCP prevalence among patients with HCV was not feasible. However, the relatively large prevalence in the majority of the studies suggests that there may be a substantial number of HCV patients at risk of bleeding complications and reduced likelihood of successful HCV antiviral treatment.

Early age at first sexual intercourse and early pregnancy are risk factors for cervical cancer in developing countries.

Early age at first sexual intercourse (AFSI) has long been associated with an increased risk of invasive cervical carcinoma (ICC). Age at first pregnancy (AFP) and ICC have been investigated less, although AFSI and AFP are strongly interrelated in most developing countries. A pooled analysis of case-control studies on ICC from eight developing countries with 1864 cases and 1719 controls investigated the roles of AFSI, AFP, and ICC risk. Age at first sexual intercourse, AFP and age at first marriage (AFM) were highly interrelated and had similar ICC risk estimates. Compared with women with AFSI > or = 21 years, the odds ratio (OR) of ICC was 1.80 (95% CI: 1.50-2.39) among women with AFSI 17-20 years and 2.31 (95% CI: 1.85-2.87) for AFSI < or = 16 years (P-trend <0.001). No statistical interaction was detected between AFSI and any established risk factors for ICC. The ICC risk was 2.4-fold among those who reported AFSI and AFP at < or = 16 years compared with those with AFSI and AFP at > or = 21 years. These data confirm AFSI and AFB as risk factors for ICC in eight developing countries, but any independent effects of these two events could not be distinguished.

Use of liquid crystal thermography in the evaluation of the diabetic foot.

Liquid crystal thermography (LCT) was used to determine temperature variations on the plantar surface of feet. The purpose was to identify thermal emission patterns associated with diabetic foot ulcers. Three population groups were screened: group I, 16 nondiabetic controls; group II, 21 diabetic patients with no history of pedal ulcers; and group III, 28 diabetic patients with active pedal ulceration or history of foot ulcerations. The results demonstrate a generalized increase in plantar foot temperature in group III compared with groups I and II. Temperature readings under metatarsal heads 1-5, great toe, heel, and lateral band were significantly increased (P less than .01) in group III. Additionally, the warm lateral surface displayed by group III patients was not significantly different in temperature from the medial arch of the foot. In groups I and II, the lateral band was significantly cooler (P less than .01) than the medial arch. In group III patients with active ulceration on only one foot, no significant difference in temperature was found between the foot with active ulceration compared with the contralateral nonulcerated foot. When patients with active pedal ulceration were compared with patients with a history of foot ulcers, no significant difference in temperature was seen at five of seven sites tested. A warm concentric color band surrounding active plantar ulcers was identified in group III. This pattern extended from the center of the ulcer to a distance of 8 mm. A significant change in temperature (P less than .01) was noted at 6- and 8-mm distances from the center of the ulcer. In addition, a mottled thermographic pattern was observed more frequently in group III patients than in groups I and II.(ABSTRACT TRUNCATED AT 250 WORDS)

Sonography of the sole of the foot. Evidence for loss of foot pad thickness in diabetes and its relationship to ulceration of the foot.

The hypothesis that loss of tissue mass in the foot contributes to foot ulceration in diabetics has never been quantitated. We developed normal criteria for the thickness of the sole of the foot at the heel, and the five metatarsal heads of both feet, using high-resolution ultrasound (10 MHz). We studied 24 normal patients ranging in weight from 125 to 250 lbs. We examined the soles of the feet of 38 diabetics without foot ulcers and 11 diabetics with foot ulcers or a history of foot ulcers who were in the same weight range as the normals. Of statistical significance, the heel thickness in controls was greater than that of the diabetics, which in turn was greater than that of the diabetics with foot ulcers. The thickness of the sole over the first and second metatarsals was also greater in the controls compared with diabetics. We conclude that high-resolution ultrasound is an effective determinant of the thickness of the sole of the foot and that diabetics have variations from the norm in the heel and at the first and second metatarsal heads.