Mr. B, a 65 year old male diabetic patient of yours, comes t…

Mr. B, a 65 year old male diabetic patient of yours, comes to see you today for weak urinary stream, incomplete bladder emptying and difficulty postponing urination in the past 2 months.  He has had no fevers, hematuria or penile discharge.  Digital rectal exam reveals a firm, smooth, symmetrical enlarged prostate, about 3.5 x 5cm.  You are unable to differentiate the median sulcus.  No other abnormals on P.E.  He most likely has: