Approximately 1:1000 pregnancies are complicated by cancer. Breast cancer is the most common type diagnosed during pregnancy. Termination of pregnancy has not demonstrated an improvement in survival. Results of an international collaborative study reported similar overall survival for patients diagnosed with breast cancer in pregnancy compared to nonpregnant patients. The consensus medical opinion supports the option to start treatment with continuation of the pregnancy. The purpose of this Cancer and Pregnancy Registry study is to prospectively follow the women diagnosed with cancer during pregnancy-collecting information about the method of diagnosis, treatment options and maternal and neonatal outcomes at delivery and yearly at follow up.