laginous areas are sometimes found in the stroma of the growth; to such the term chondrocarcinoma is applied. More or less complete destruction of the testicle and epididymis is frequent, but the tunica albuginea usually resists invasion for a considerable time. Carcinoma of the testicle seems to originate from the epithelium

of the convoluted tubules. Metastasis through the lymphatics and blood-vessels is frequent, and extension through the testicular envelopes to the skin may occur.

Cysts. Retention-cysts of the tubules are frequent in cases of inflammation and induration of the testis and epididymis. Sometimes they contain a simple milky liquid; in other cases spermatozoa are found in the fluid, and to these cysts the term spermatocele is applied. The cysts may be numerous and small, or may be very large, containing a hundred or more cubic centimeters of liquid. The cysts are found in the body of the organ; but, when large, project from the surface. Very large cysts push the testicle and epididymis to one side. Occasionally cysts originate from the hydatids or the paradidymis. These may be spermatoceles, when one of the vasa aberrantia opens into them.

Secondary proliferations of the epithelium of the cysts may convert a simple into a papilliferous cystoma; and occasionally

the primary process seems to be one of adenomatous character, the cystic condition being the result of secondary distention or of the peculiar character of the acini formed.

Small cystic cavities may contain mucous liquid or thick, curdy material. In the latter case the term atheromatous cyst is applicable.

Dermoid cysts are occasional tumors of the testis proper. They may be simple sacs, lined with epidermal tissue and filled with pultaceous matter; or complicated dermoids, containing teeth, bone, muscle-fibers, and nerve-tissue.

PARASITES.

Echinococcus-cysts are rarely met with.

THE PROSTATE GLAND.

INFLAMMATION.

Inflammation of the prostate, or prostatitis, is most frequently secondary to posterior urethritis. Sometimes, however, it results from other causes, such as metastatic involvement in general pyemia or other forms of infection. Inflammations in the vicinity and direct injuries of the prostate may likewise cause acute inflammation.

Pathologic Anatomy.-A simple and a suppurative form may be distinguished.

Simple Prostatitis. In the ordinary prostatitis following urethritis the disease takes the simple form, the gland being congested and swollen, and causing by its enlargement more or less obstruction of the urethra. Small suppurative foci may be formed in and about the glandular pouches and tubules.

Suppurative or phlegmonous prostatitis, or abscess of the prostate, may be a terminal condition of the previous form, or it may be developed primarily. In cases of metastatic prostatitis a number of foci of suppuration may occur and subsequently coalesce, or a diffuse suppurative infiltration may take place. The development of abscesses is usually acute, though in some cases it may occur insidiously. If the abscesses are small they may subsequently undergo encapsulation, inspissation, and even calcification. Larger abscesses are prone to rupture into the urethra, usually through a number of openings. Sometimes, however, the inflammation extends to the tissues around the gland, causing periprostatitis, and later rupture into the rectum may occur. Extensive phlegmonous inflammation of the pelvic tissues is an unusual result.

ATROPHY AND DEGENERATION.

Atrophy of the gland is occasionally met with in youthful individuals, and may be the result of disease or removal of the testis. It also occurs in the aged, and in this case atrophy of the tissues surrounding the prostatic ducts may be accompanied by dilatation of the ducts themselves. The gland then presents a cavernous appearance. Atrophy of the gland sometimes leads to incontinence of urine.

Fatty degeneration of the epithelium of the gland and of the muscle-fibers is frequent in old age, and may occur as an independent condition or in association with hypertrophic enlargement of the gland. The gland becomes soft, and diffusely yellow or mottled in color.

CONCRETIONS.

Prostatic concretions are not unusual in persons of advanced age, and are frequently found in considerable numbers. They vary in size from almost microscopic granules to bodies the size of a millet-seed. On section through the gland these brownishcolored bodies give the appearance of a surface sprinkled with snuff. The granules are usually round or oval, and are characterized by concentric lamellations. They may be colorless at first, but usually become brownish. The term amylaceous bodies has been applied to them, and they have been supposed, though erroneously, to be composed of amyloid material, such as occurs in amyloid degeneration. When they reach considerable size calcareous salts may deposit around them and give them an irregular form. Sometimes the concretions are discharged through the prostatic ducts into the urethra; in other cases the larger concre tions project prominently into the urethra beneath its mucous mem brane.

INFECTIOUS DISEASES.

Tuberculosis of the prostate is usually found in association with tuberculosis of the other genital organs, especially the vas deferens and epididymis. It is also met with in association with tuberculosis of the bladder or kidney. The prostate is usually diffusely enlarged, and may be somewhat nodular upon the surface. On section caseous areas are found, or the entire gland has a caseous appearance. Recent tubercles are rarely visible, as caseation progresses with unusual rapidity in this organ. Primary tuberculosis of the prostate is rare.

HYPERTROPHY AND TUMORS.

Hypertrophy of the prostate is a condition sometimes inflammatory in character, sometimes more probably of the nature of

tumor-formation. It occurs most frequently in the aged. The causes are often quite obscure. In some cases chronic posterior urethritis seems to be the important factor; in other instances disturbances of the circulation, and especially varicose conditions of the veins, are active in the causation.

FIG. 331.-Hypertrophy of the middle lobe of the prostate: A, middle lobe of prostate;
B, urethra (White and Wood).

The organ may enlarge in a uniform manner, or there may be nodular or localized swelling. Of the localized form the most im-portant, from a clinical aspect, is that in which the middle lobe or the isthmus of the gland enlarges and projects under the posterior wall of the urethra as a small or large rounded elevation, or as a

transverse bar or obstruction (Fig. 331). According to the investigations of some authorities, the enlargement in such instances is due to a hyperplasia of accessory prostatic tissue lying immediately under the mucous membrane of the bladder and of the prostatic portion of the urethra, with subsequent involvement of the isthmus of the gland itself.

On section through the gland there may be a uniform induration, or in other cases, in consequence of associated changes in the epithelial or glandular elements, there may be scattered through the gland areas of softening or of proliferation of the glandular elements, or cystic distentions of the gland-tubules. In such instances the indurated gland presents more or less softened or cystic foci.

Microscopically, in the diffuse form, involving the stroma alone, the gland presents merely the features of uniform fibromyomatous

FIG. 332.-Section of hypertrophied prostate of a man aged 74 years; natural size: 6, urethra; b, colliculus seminalis (Socin).

proliferation, and corresponds in structure with fibromatous or myofibromatous tumors of the uterus (Fig. 332). In other cases the glandular elements take an active part in the pathologic process, and a distinctly adenomatous character is added. The glandular elements may undergo fatty degeneration, and the lumina of the acini and tubules may be filled with milk-like, fatty material. In other cases pronounced cystic distention of the gland occurs.

Results of Hypertrophy of the Prostate.-Enlargements of the prostate usually interfere with the discharge of urine. This is particularly marked in cases in which the middle lobe projects into the urethra, though in some instances the opposite result may be produced, viz., incontinence of urine due to interference with