My Husband Was Diagnosed With Multiple Myeloma With Amyloidosis And

My husband was diagnosed with multiple myeloma with amyloidosis and had a stem cell transplant in 2012 and is current on a 5 mg revlimid regiment. We noticed that there has been some bright red blood in his stool while going to the bathroom and some hemmorids. I looked in the anal area and noticed there was some purple bruising along the inside of the crack close to the hemmorids. I looked online and it mentiontioned sever times about rectal cancer. Could this be what it possibly is? We have a scheduled appoint with our multiple myeloma doctor this Thursday but I am just curio about what I have been reading online in regards to rectal cancer.
Thank you
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