Only cumulative exposure duration of ≥5 years to prolactin-increasing antipsychotics was associated with increased odds of both ductal adenocarcinoma (aOR = 1.40, 95% CI = 1.17–1.68) and lobular adenocarcinoma (aOR = 1.65, 95% CI = 1.11–2.45). This evidence concerns the gene PRL and breast lobular carcinoma.