A 68-year-old man from Delhi presents with lower urinary tract symptoms: nocturia (3–4 times per night), weak urinary stream, and incomplete emptying for the past 8 months. Digital rectal examination reveals a smooth, firm, symmetrically enlarged prostate without nodules. Serum PSA is 2.8 ng/mL (normal <4 ng/mL). Transrectal ultrasound shows uniform glandular enlargement. Post-void residual urine is 120 mL. What is the most likely histopathological diagnosis?

Explanation

## Clinical Presentation & Diagnosis This patient has classic **benign prostatic hyperplasia (BPH)** — the most common prostatic pathology in elderly men. ### Key Diagnostic Features | Feature | Finding | Significance | |---------|---------|---------------| | **Age** | 68 years | BPH prevalence increases with age; ~50% at 60 yrs, ~90% at 85 yrs | | **LUTS** | Nocturia, weak stream, incomplete emptying | Obstructive symptoms from urethral compression | | **DRE** | Smooth, firm, symmetrical enlargement | Benign pattern; nodules suggest malignancy | | **PSA** | 2.8 ng/mL (normal) | Low PSA argues against malignancy | | **Imaging** | Uniform glandular enlargement | Diffuse hyperplasia, not focal lesion | | **Post-void residual** | 120 mL | Indicates bladder outlet obstruction | ### Histopathology of BPH **Key Point:** BPH is characterized by **proliferation of both stromal (smooth muscle, fibroblasts) and glandular (epithelial) elements** in the transition zone of the prostate. The hyperplastic nodules compress the urethra, causing obstructive symptoms. **High-Yield:** The pathogenesis involves: 1. Increased DHT (dihydrotestosterone) signaling via androgen receptors 2. Increased growth factors (FGF, EGF, IGF-1) 3. Altered apoptosis–proliferation balance favoring growth 4. Stromal–epithelial interactions amplify proliferation ### Microscopic Features - **Glandular component:** Hyperplastic acini lined by normal cuboidal/columnar epithelium; no atypia - **Stromal component:** Proliferation of smooth muscle bundles and fibrous tissue - **Architecture:** Nodular pattern; compression of central urethra - **Cytology:** Benign nuclei; no mitotic abnormalities **Clinical Pearl:** BPH is a **histological diagnosis** confirmed by transurethral resection of prostate (TURP) or biopsy, but clinical diagnosis relies on LUTS + DRE findings + imaging. PSA may be mildly elevated in BPH (due to increased epithelial surface area) but is not diagnostic. ### Why Not Malignancy? - Normal PSA level - Smooth, symmetrical DRE (not nodular/hard) - Uniform imaging (not focal) - Obstructive LUTS (BPH typical); cancer often asymptomatic early [cite:Robbins 10e Ch 20]