Risk factors for wilms' tumor: a case - control study, Alexandria

Wilms' tumor is a rare malignant neoplasm of childhood with a wide range of world wide variability due to risk variability. Several maternal, paternal and environmental risk factors have been reported to be strongly, moderately and potentially linked to Wilms' tumor. A hospital based case control study was conducted in 2002 to assess risk factors for Wilms' tumor in Alexandria. A total of 77 recently diagnosed and pathologically confirmed Wilms' tumor cases were enrolled from the hospitals currently covered by Alexandria Cancer registry. A total of 176 control subjects were randomly selected from outpatient's clinics of the same hospitals. Control subjects were matched by age and, sex. All mothers were subjected to a pre designed specific questionnaires about socio- demographics, lifestyles, paternal jobs and history of exposure to specific drugs and environmental agents. Univariate and multivariate analysis were performed to calculate the odds ratios [OR]. Populations attributable risk percent [PAR%] was reported. Interactions between risk factors were assessed and reported as Rothman synergy index [SI]. Maternal use of hair dyes during pregnancy showed a high risk of developing Wilms' tumor with an OR of 1.6 for occasional and of 6.2 for frequent use. Both edema during pregnancy and/or hypertension almost double the risk of developing Wilms' tumor. Among the paternal risk factors, blue collar occupations for at least 6 months after the age of 18 years were also reported to increase the risk [OR=4.9, 95% CI,2.5-9.6]. Likewise household exposure to pesticides was reported to increase the risk up to 4 times. Interaction between maternal vaginal infection and paternal occupation were significantly synergetic [SI=1.2]. An increased strength of associations were reported across the categories of paternal smoking, frequency of maternal use of hair dyes and/or coffee intake. The highest PAR% was reported for antenatal maternal use of hair dyes and coffee consumption. Avoidance of maternal exposure to hair dyes, coffee intake and, vaginal infection during pregnancy could minimize the risk of giving birth to a child threatened with Wilms' tumor. Larger comprehensive studies are recommended

audit of the quality of data in the National Cancer Registry, King Khaled University Hospital, Riyadh, Saudi Arabia, 2000.: a statistical approach

The completeness of case ascertainment was assessed through the utilization of multiple data sources including medical records, pathology reports and death certificates by employing a capture- recapture method and building up several log linear models. The validity of data by re-abstracting random sample [10%] of records to assess the minor and major disagreement of certain items and timeliness of data through calculation of reporting delay time [RDT] was investigated. A total of 991 cancer cases was reported in the registry during the study period, 71.4% of them had medical records, 77.5% had pathology reports and 28.1% had death certificates. A total of 571 missed cases was identified from the overlapping sources of reporting and fitting log linear models which assured the dependency of the reporting methods. The adjusted rate of ascertainment was 63.4%. The stage of cancer showed the highest major disagreement [43.6%], followed by the histology and primary site [25.6% and 10.3%, respectively] and the date of diagnosis [23.1%]. On the other hand, 250 cases showed RDT less than 6 months