Health and Prostate

The Department of Urology of the New York Hospital
(Given January 31, 1941)

Prostatic Calculus

Incidence and Etiology. Prostatic calculi are relatively common. In an autopsical study of 250 prostates from subjects of all ages, I found one or more stones in approximately one-fifth of the glands.

Prostatic calculosis may occur at any period of life, but is rare before the age of 30 years. Of the twenty-three patients reported on by Lowsley and Hawes, only one was under 40 years of age.

Distinction must be made between (1) endogenous, or true prostatic calculi, namely, concretions formed within the prostatic substance, and (2) exogenous, or false calculi, which are urinary stones that have lodged in the prostatic urethra or have formed primarily from urinary sediments in a communicating pouch. The nucleus of a true prostatic stone is composed of organic material of an albuminoid nature: corpora amylacea, a blood clot, epithelial detritus, a clump of bacteria, or necrotic tissue from an abscess. The inorganic element forming the laminated layers about the nucleus is composed of inorganic salts.

The exact etiology of true prostatic stones is unknown. The most commonly held theory is that first advanced by Thompson in 1868, namely, that they have their origin in corpora amylacea, which, under certain conditions, act as foreign bodies and set up an inflammatory reaction in the mucous membrane of the acini enclosing them, as a result of which calcium phosphates and carbonates are cast off; these impregnate the corpora amylacea and convert them into calculi.

Pathology. True prostatic calculi are usually multiple, small, rounded (without facets), and scattered indiscriminately throughout the parenchyma. Occasionally a cluster of stones will be found in one lobe while the remaining lobes are free of calculi. Sometimes there will be a single large stone, or one large stone in association with numerous smaller ones.

Microscopically, the portion of the gland containing the calculi shows distended acini, the mucosal linings of which are infiltrated by lymphocytes or by polymorphonuclear leukocytes.

Benign adenomatous hypertrophy and prostatic calculosis not infrequently occur together (18 of 23 cases, Lowsley and Hawes). The calculi are seldom, if ever, located within the adenoma, but are found between it and the capsule, embedded in the remnants of the true prostate. Frequently, however, calculi-containing prostates show no sign of hypertrophy. They may be senile and fibrotic, with atrophy of the parenchyma and evidence of inflammation.

Symptoms and Diagnosis. The most important symptoms are disturbances of urination, the actual passage of calculi either spontaneously or following massage, and localized or referred pain — in the perineum, suprapubic region, rectum, or down the penile shaft. In many cases the symptoms are overshadowed by those of an associated hypertrophy or prostatitis. In others, no symptoms are present, and the stones are discovered accidentally.

It .is frequently possible to make a presumptive diagnosis of prostatic calculi by the rectal palpation of a hard, circumscribed area suggestive of stone or a nodule, or by the eliciting of crepitation. Urethroscopic examination may reveal the presence of stones in the prostatic ducts. Positive diagnosis is made by roentgenography. Cysto-urethrograms are of value not only in revealing the calculi, but in determining the type and degree of obstruction to urination, and associated pathology, if present.

Treatment. Small calculi, that are discovered accidentally and give no subjective symptoms, are best left alone. In older men, who have neared the end of sexual life, we prefer to treat prostatic calculosis by total prostatectomy, both when there is associated adenomatous hypertrophy and when there is no hypertrophy but infection and fibrosis are present. Prostatotomy, transurethral resection, and even the usual conservative perineal or suprapubic prostatectomy often leave enough calculi or infected prostate to cause persistence or recurrence of symptoms, as has been repeatedly demonstrated by postoperative roentgenograms. Younger men with numerous stones in their prostates should be treated by prostatectomy as a rule. Transurethral resection is also frequently employed, but has the disadvantage that stones are often left behind in the prostate.