Organochlorine residues in adipose breast tissues and risk of breast cancer in Egyptian females

ABSTRACT

Exposure to environmental estrogen such as organochlorine pesticides and industrial chemicals has been proposed as a cause of increasing rates of breast cancer. To test this hypothesis 0.2-1 gm of breast adipose tissue was biopsied from 150 Egyptian females seen for evaluation of a palpable breast mass at the National Cancer Institute, Cairo University in the period from September 1995 to September 1997. Data on established risk factors for breast cancer were obtained by standard questionnaires. Mammary infiltrating carcinoma was diagnosed in 58 females [cases] while benign breast disease was diagnosed in 92 females [controls]. Elevated levels of organochlorine compounds were found in fat samples from women with cancer compared with those who had benign breast disease reaching a statistically significant difference for DDE, beta HCH and heptachlor [P < 0.05]. When comparing organochlorine levels according to estrogen receptor status [ER], the mean adipose tissue levels in ER-positive cases were significantly higher than ER-negative cases as regards DDE, beta HCH and heptachlor [P < 0.05]. Exposure to high levels of DDE was associated with significant higher risk of breast cancer [Odd ratio adjusted for age and BMI] was 6.8 increased to 8.8 when estrogen receptor status entered into the model. In conclusion: The present work support but not prove the hypothesis that exposure to 2,2-bis [p-chlorophenyl] 1,1,1, trichloroethane [DDT] increases the risk of breast cancer among Egyptian females