He found that a failed contraceptive, tamoxifen, could block the growth of cancer cells, opening up a whole new class of treatment. He found that a failed contraceptive, tamoxifen, could block the growth of cancer cells, opening up a whole new class of treatment. Jordan, V Craig, Deaths (Obituaries), Breast Cancer, Tamoxifen (Drug), University of Texas M D Anderson Cancer Center, Drugs (Pharmaceuticals), Research NYT > Science