Her research group currently focuses on three principal research lines: (1) The assessment of the long‑term risks of second malignancy, cardiovascular disease and other comorbidities following treatment of Hodgkin lymphoma, breast cancer, testicular cancer and childhood malignancy; the development and evaluation of cancer survivorship care programs. (2) A topic related to late effects of cancer treatment concerns our research related to breast implants. In 2008 we reported the first epidemiological study demonstrating that breast implants are associated with a strongly increased risk of a rare type of breast lymphoma, i.e. anaplastic large-cell lymphoma (ALCL) (3) The assessment of the roles of and hormone-related and genetic risk factors in the etiology of breast and ovarian cancer; special interest is in late effects of ovarian stimulation for in Vitro Fertilization and cancer etiology in BRCA1/2 families. She has been awarded a large number of grants on late adverse effects of cancer treatment; in addition she established and coordinates the Dutch BETER consortium, aimed at the establishment of survivorship clinics for survivors of lymphoma in 24 Dutch hospitals. In 2019 she was awarded the 17th Rosalind E. Franklin Award for Women in Cancer Science from the U.S. National Cancer Institute. Since 1998 Flora van Leeuwen holds a Chair in Cancer Epidemiology at The Faculty of Medicine from the University of Amsterdam.