What Causes Weight Loss And Clay Colored Stools?

My dad is a 90yr male. he has Hypertension. DM II , Alzheimers dis. and diagnosed and treated for rectal cancer in march of 2010. completed radiation tx. unable to complete chemo due to intolerance of meds. He has had chills for the past year. he has a poor appitite and is losing wt, approx 10ibs in the past months. He recently has had clay colored stools. He is taking 20mg of lisinopril QD, 2mg of immodium QD, 5mg of aricept, and recently started on bicalutamide 50mg for prostate ca. PSA in Jan. 2014 was 1.69. His last lab in nov. of 2013 consisted of CMP, CBC,hemoglobin A1C(7.1) thyroid profile. all other values were normal except for the lymphocyte ct. of 14.4.
He is pale but no jaundice noted. He has increased weakness and sleeps 18-20 hr day. I suspect the cancer has reoccured in his bile duct. What is your opinion?