Marisa had recovered spontaneously from a case of stage IV cancer. The doctors who treated her could not explain it, so her father thought it was a miracle and pledged to God that he would re-enact Christ's crucifixion every year she remained alive. During one of these re-enactments, he became extremely ill and was hospitalized.
Because of her father's behavior, Marisa's mother had left him years before.
When Ramon was diagnosed with Marburg Multiple Sclerosis, the only available treatment was derived from stem cells harvested from aborted fetuses. He refused on religious grounds. However, Marisa implored him to accept treatment. When he said he was refusing because that's what God wanted, Marisa denounced God in front of him.
In order to get him to accept treatment, House lied to Ramon, telling him Marisa's cancer had returned. He was soon on the road to recovery.