Prostate Problems
Could be a simple problem
Could be cancer

Prostate problems are, basically of three types.

Here is what Wikipedia has to say on this topic

Prostatitis is inflammation of the prostate gland. There are different forms of prostatitis, each with different causes and outcomes. Acute prostatitis and chronic bacterial prostatitis are treated with antibiotics; chronic non-bacterial prostatitis or male chronic pelvic pain syndrome, which comprises about 95% of prostatitis diagnoses, is treated by a large variety of modalities.

Benign prostatic hyperplasia (BPH)) occurs in older men (aren't we sooooo lucky?); the prostate often enlarges to the point where urination becomes difficult. Symptoms include needing to go to the toilet often (frequency) or taking a while to get started (hesitancy). If the prostate grows too large it may constrict the urethra and impede the flow of urine, making urination difficult and painful and in extreme cases completely impossible.

BPH can be treated with medication, a minimally invasive procedure or, in extreme cases, surgery that removes the prostate.

Prostate cancer is one of the most common cancers affecting older men in developed countries and a significant cause of death for elderly men (estimated by some specialists at 3%). Regular rectal exams, as well as measurement of Prostate Specific Antigen are recommended for older men, usually ages 50 and up to detect prostate cancer early.
(MORE LUCK! NOT!)