Carcinoma of the prostate, [s8]common

Carcinoma of the prostate is the commonest male cancer over the age of 65. It presents with: (1) Obstructive symptoms, including difficulty passing urine, or acute or chronic retention; this has no specific features. (2) Bone pain (common), which is is not necessarily in the back. Perineal pain suggests extensive local disease. (3) Weakness in the legs, due to secondaries involving the cauda equina (uncommon). 80% of patients have metastases when they present.

Because carcinoma of the prostate is so common, it is fortunate that it can be controlled, for a time, by the cheapest kind of hormone therapy[md]stilboestrol. You may, however, have difficulty persuading patients to continue to take it.

Histology usually gives the correct result, but the microscopic differentiation of carcinoma from benign hyperplasia can be difficult. Make the diagnosis on the basis of the clinical findings, the serum acid phosphatase, the X-ray findings and the histology.

Fig. 32-17a PROSTATIC BIOPSY. A, holding the needle along the palmar surface of your left index finger, with the point on the pulp, insert it into the patient's anus. B, feel each lobe of his prostate, as if you were doing a rectal examination. Using your right hand, push the needle 0.5 cm through his rectal mucosa, towards one of the lobes of his prostate. Withdraw the stylet. C, insert the biopsy jaws, and push them into his prostate as far as they will go, still keeping the needle along the index finger of your left hand. Remove your finger. D, advance the outer sheath far enough to cover the biopsy jaws. E, rotate the needle, so as to break off the core of tissue that has been grasped, and withdraw it. Lift the core of tisue from the biopsy needle, with an ordinary injection needle, and put it into formol saline. If you fail, repeat the process up to 3 times. Then do the same thing with the other lobe.

CARCINOMA OF THE PROSTATE RECTAL EXAMINATION. A normal prostate feels smooth, symmetrical, and firm, usually with a median groove and mobile rectal mucosa. A carcinomatous prostate is hard, nodular, and asymmetrical; its median groove is often obliterated, and the rectal mucosa may be fixed to it. Late locally extensive disease may extend to the pelvic wall, form a band round the rectum, and fix the pelvic tissues. Sometimes, you can feel the spread of the tumour in the tissues round the prostate. If possible, confirm these findings by examining the patient bimanually under anaesthesia (see below).

X-RAYS. Look for lytic and sclerotic (typical but less common) secondaries in his pelvis, and lumbar spine. Paget's disease and osteoarthritis produce similar bony symptoms, but show different X-ray changes.

SPECIAL TESTS. If his carcinoma has spread beyond his prostatic capsule, his serum acid phosphatase will be [mt]3 King[nd]Armstrong units. A normal level does not exclude it. A persistently raised level supports the diagnosis, and suggests metastasis. It has no prognostic value, its main use is in diagnosis. It falls in response to treatment, and rises when the disease reactivates.

CAUTION ! Take the blood for his acid phosphatase before you examine him rectally, or take it more than 48 hours later. If you take it immediately afterwards, you will get an abnormally high reading.

EUA AND CYSTOSCOPY. Examination under anaesthesia (EUA) is the more useful of these two investigations. If possible cystoscope him; this is particularly useful in distinguishing carcinoma of the prostate from carcinoma of the trigone of the bladder infiltrating the prostate. You may feel a grating sensation, as you pass the cystoscope through his carcinomatous prostate, or you may see puckering of the apex of his trigone, or submucous nodules in his bladder (late signs).

NEEDLE BIOPSY OF THE PROSTATE. If you diagnose carcinoma of the prostate when you are examining a patient under anaesthesia for retention of urine, biopsy his prostate with a Vim[nd]Silverman needle through his rectum, as in Fig. 32-17a. This is not difficult and usually gives the correct result. In spite of the fact that you do it through his rectum, serious infection is rare.

THE DIFFERENTIAL DIAGNOSIS includes benign prostatic hyperplasia, carcinoma of the bladder infiltrating the prostate, bladder-neck fibrosis (23.20), and stricture of the posterior urethra (23.8).

THE MANAGEMENT [s7]OF CARCINOMA OF THE PROSTATE If his disease is still confined to his prostatic capsule, and he is under 65, refer him (if you can) for radical radiotherapy.

If this is impractical, or the disease is late, give him stilboestrol daily for the rest of his life. Start with 1 mg daily, and if this fails to control his symptoms increase it to 5 mg. There is an 80% chance that he will show a response. With this low dose there is little risk of cardiovascular complications, but some itching and enlargement of the breasts are common. If necessary, you can do a bilateral mastectomy (21.5, 30.9).

Alternatively, consider doing a standard or a subcapsular orchidectomy (23.25), which will avoid the need for life-long stilboestrol treatment and its possible complications. Most patients don't like this, because their testes become small! To remove them completely is even less acceptable. Discuss his management clearly with him.

If he has retention of urine, give him stilboestrol and pass an indwelling Gibbon or Foley catheter. Leave it in for at least 3 weeks, before trying to remove it, and if he still cannot pass urine adequately, consider leaving it in for a further 3 weeks. Stilboestrol treatment will usually make his prostate shrink enough to let him pass urine. If it does not (unusual), refer him for transurethral resection of his prostate. If this is quite impossible, leave him with a urethral or suprapubic catheter. Don't try to remove his prostate by Freyer's method (23.19): this is difficult, because it does not shell out properly, and he will bleed severely.

If his urine becomes infected, treat him with antibiotics or nitrofurantoin; in itself infection will not influence the outcome of his carcinoma.

CAUTION ! Avoid prostatectomy. It can cause much bleeding. Most cases present with retention, and can be managed with a catheter and stilboestrol.