Enlarged Prostate

BPH leads to prostatic enlargement that may be either circumscribed (see below) or diffuse. BPH is a nodular proliferation of glandular tissue and stroma (fibrovascular/fibromuscular) of the inner periurethral zone.

The volume of the prostate is determined by multiplying length (longitudinal ultrasound section) × width × depth (in transverse section) and dividing the product by the factor 0.523 (this calculation is already built into scanners

and documentation programs). This formula is fairly accurate in transabdominal ultrasound but is more accurate in transrectal scanning. Here too, however, the measured volume deviates from the actual volume or weight by up to 20%.2 Normal volume is 20 (–25) mL. Enlargement in excess of 80 mL is generally referred for transabdominal prostatectomy. However, estimated size alone is not a reliable

●Predominantly hypoechoic or irregular structure

●Peripheral asymmetrical tumor structures

●Irregular outlines

●Capsule breached

●Invasion of seminal vesicles, less commonly of the bladder floor

●Locoregional lymphogenous spread, distant metastases

●Prostate shows low central echogenicity with rounded outlines

●Central hypoechoic tumor structure in the median lobe, indenting the bladder floor

●Smooth outlines

●Capsule intact

●Displacement, atrophy, and encapsulation of normal peripheral glandular tissue

●Possible echo-free or echogenic areas

Clinical Diagnosis of Prostatic Carcinoma6

An effective early diagnostic procedure for prostatic carcinoma consists of DRE with assessment of overall size, median sulcus, surface characteristics, and consistency (a circumscribed or diffuse “stony hard” consistency is suggestive of malignancy), combined with the determination of PSA. If induration is noted at palpation and the PSA is between 4 ng/mL (upper normal limit in men > 60 years of age; lower in younger men) and 10 ng/mL, there is a 41% chance that carcinoma is present. With a PSA in excess of 10 ng/mL, this rises to 72%. The incidence of carcinoma is 69% in cases where a hard, discrete nodule is

found in the prostate, and 91% when the corresponding PSA is higher than 10 ng/ mL. Thus, the digital findings and PSA are both critical in the detection of prostate cancer.

Transurethral sonography can support a presumptive diagnosis of carcinoma, and core biopsy can confirm the diagnosis. Even with a negative histology, however, a high PSA is still considered suspicious for carcinoma, as it is a specific tumor marker. It is extremely rare for a histological prostatic malignancy to be identified as a sarcoma or malignant lymphoma.