I offered to show a picture of my large lump that seemed to grow only on my left butt cheek? (photo)

  If you have not met with a couple of board certified plastic surgeons, I would do this.  This could be a couple of things, and an exam can help with the diagnosis.Kenneth Hughes, MDLos Angeles, CA

Although it is a little hard to tell what is may represent a vascular malformation v. traumatic tissue/scar hypertrophy from photos, I'd recommend a thorough review of your scans and possibly an additional study to focus on soft tissue such as an MRI. An MRI or CT study can be ordered as a CT Angiogram or MRI in a similar manner to evaluate the vascular flow through the area. After determining the what the blood flow is through the area, excision can be discussed. Best Wishes!!

I think that you need a thorough exam and review of your studies in person. You shoudl go to a specialist dealing in the field of arterio-venous malformation (AVM's). It may be an AVM and an MR angiogram may be helpful. Good luck.

Based on the pictures posted, the purple birth mark, is a hemangioma, port wine stain. The growth under the stain could be a hemangioma, A-V malformation. These can grow in size. You needan MRI specific to the buttock, where discussion with the radiologist to look for hemangioma, A-V malformation. There are many doctors who specialize In vascular malformation, that you need to consult for appropriate diagnosis. An arteriogram will be diagnostic. A consult with some one who specialize in vascular malformation in a major university center is needed.