, I'm sure someone will come along shortly to give you a more definite answer to your question. On internet search these are the definitions I've gathered:
-- False or counterfeit; fake.
-- Decidua is the term for the uterine lining (endometrium) during a pregnancy. It is formed under the influence of progesterone and serves to support and interact with the gestation. The decidua represents the maternal portion of the placenta.
-- An abnormal increase in the number of cells in an organ or a tissue with consequent enlargement.
I hope you'll get a more satisfactory answer about the disease itself and if it is cancerous or not very soon....