Could this be umbilical endometriosis? I have umbilical pain for 1.5 years. I was told I have a hernia but I'm not convinced.

I had the umbelical hernia repair 9 months ago (laporoscopically) but continue to have very localized umbelical pain. I also have endometriosis. Last week I developed a growth in my belly button that is very painful to touch. It was aspirated and found to have blood but no infection. Cultures negative. CT abdomen shows 1.5 cm umbelical lesion that looks round and has old blood inside of the lesion. Not cystic. They said it is a post surgical seroma but 9 months post op seems unusual.

No doctor answers yet