Meta-analysis of chromosomal aberrations as a biomarker of exposure in healthcare workers occupationally exposed to antineoplastic drugs.

Many antineoplastic drugs used to treat cancer, particularly alkylating agents and topoisomerase inhibitors, are known to induce genetic damage in patients. Elevated levels of chromosomal aberrations, micronuclei, and DNA damage have been documented in cancer patients. Elevations in these same biomarkers of genetic damage have been reported in numerous studies of healthcare workers, such as nurses and pharmacists, who routinely handle these drugs, but results vary across studies. To obtain an overall assessment of the exposure effect, we performed a meta-analysis on data obtained from peer-reviewed publications reporting chromosomal aberration levels in healthcare workers exposed to antineoplastic drugs. A literature search identified 39 studies reporting on occupational exposure to antineoplastic drugs and measurement of chromosomal aberrations in healthcare workers. After applying strict inclusion criteria for data quality and presentation, data from 17 studies included in 16 publications underwent meta-analysis using Hedges' bias-corrected g and a random-effects model. Results showed the level of chromosomal aberrations in healthcare workers exposed to antineoplastic drugs was significantly higher than in controls. The standardized mean differences (difference of means divided by within sd) from all studies were pooled, yielding a value 1.006 (unitless) with p<0.001. Thus, in addition to the documented genotoxic effects of antineoplastic drugs in cancer patients, this meta-analysis confirmed a significant association between occupational exposure to antineoplastics during the course of a normal work day and increases in chromosomal aberrations in healthcare workers. Based on the studies reviewed, we were unable to accurately assess whether appropriate use of protective measures might reduce the incidence of genetic damage in healthcare workers. However, given the potential for increased cancer risk linked to increases in chromosomal aberrations, the results of this study support the need to limit occupational exposure of healthcare workers to antineoplastic drugs as much as possible.