Hi and thanks for the query, This might require a keen clinical evaluation. A prostate hypertrophy must be carefully excluded. Enlargement of the prostate could explain very well his pain on urinating and feeling of incomplete emptying of his bladder. The relation between the prostate, bladder and prostate are very close. I suggest a possibility of prostate tumor spreading to the rectum be urgently excluded. A rectosigmoidoscopy, an examination to explore the nature of the rectum and sigmoid colon could be very beneficial. Your doctor after doing an anal examination, prostate ultrasound, prostate Specific antigen (PSA) measurement and a rectosigmoidoscopy should be in position to explain with high degree of certainty the symptoms and propose an appropriate management and follow up plan. I suggest you consult a Urologist. Thanks and kind regards. Bain LE, MD.