Residential Pesticide Exposures in Pregnancy and the Risk of Sporadic Retinoblastoma: A Report From the Children's Oncology Group

PURPOSE: To examine whether parental pesticide exposure contributes to the development of sporadic retinoblastoma. DESIGN: Case-control study. METHODS: Data were collected by a large multicenter study of sporadic retinoblastoma in which parents of 99 unilateral and 56 bilateral age-matched case-control pairs were interviewed by telephone. Retrospective exposure information was collected on the type, location, timing, and frequency of residential pesticide use. We used conditional logistic regression analyses to estimate odds ratios for maternal pesticide exposure in the month before or during pregnancy and to assess whether the type of product, and the circumstances under which it was applied, were associated with risk of disease. RESULTS: Unilateral retinoblastoma was associated with parental insecticide use (odds ratio [OR], 2.8; confidence interval [CI], 1.1-6.7) and the use of professional lawn or landscape services (OR, 2.8; CI, 1.0-8.2). For bilateral disease we observed large point estimates for several exposures but the small number of cases rendered these results uninformative (ie, resulted in wide confidence intervals). Whether parents used the pesticide inside vs outside the home did not appear to modify risk estimates for unilateral retinoblastoma (OR, 2.5; CI, 0.9-7.0 vs OR, 2.5; CI, 1.0-6.5), nor did the type, frequency, timing related to pregnancy, or applicator of pesticide used influence estimates to an appreciable degree for disease. CONCLUSIONS: Our results suggest that parental pesticide exposure before or during pregnancy may play a role in the development of childhood retinoblastoma. Retrospectively collected exposure data introduces the possibility of recall bias; therefore, results should be interpreted cautiously until additional studies are conducted. (C) 2017 Elsevier Inc. All rights reserved.