Prostate carcinoma is a malignant tumor arising mainly from the glandular epithelium of the prostate. It is one of the most common cancers in men and the second leading cause of cancer-related deaths. Most cases are adenocarcinomas originating in the peripheral zone of the prostate.
📍 Anatomy and Sites of Origin
The prostate surrounds the urethra just below the bladder. The gland is divided into zones — peripheral, central, transitional, and anterior fibromuscular stroma. Most carcinomas arise from the peripheral zone, making them palpable on digital rectal examination (DRE).
- Peripheral zone: Common site of carcinoma
- Transitional zone: Common site of benign prostatic hyperplasia (BPH)
🧬 Pathogenesis
Prostate carcinoma develops due to a complex interplay between hormonal, genetic, and environmental factors. Androgen-dependent proliferation plays a key role, as tumor growth requires testosterone and dihydrotestosterone (DHT).
Hormonal Influence
- Androgens stimulate prostate epithelial cell growth
- Increased 5α-reductase → elevated DHT levels
- Anti-androgen therapy helps slow progression
Genetic Factors
- BRCA2 and PTEN mutations increase risk
- Family history of prostate or breast cancer significant
Environmental/Lifestyle
- High-fat diet, obesity, and aging
- Possible role of chronic inflammation
🧫 Morphology
- Gross: Hard, irregular nodules in the peripheral zone
- Microscopic: Small, crowded acini with prominent nucleoli and loss of basal cells
- Graded using the Gleason scoring system (based on glandular differentiation)
⚠️ Clinical Features
In early stages, prostate carcinoma is often asymptomatic and detected incidentally during screening. As the tumor progresses, urinary and metastatic symptoms appear.
Local Symptoms
- Weak urinary stream
- Hesitancy and frequency
- Hematuria (late sign)
Metastatic Symptoms
- Bone pain (especially spine and pelvis)
- Weight loss and fatigue
- Pathological fractures
🔍 Diagnosis
| Investigation | Purpose | Findings |
|---|---|---|
| Digital Rectal Exam (DRE) | Palpate posterior lobe | Hard, irregular nodules |
| Prostate-Specific Antigen (PSA) | Screening and monitoring | Elevated levels (>10 ng/mL suggestive) |
| Transrectal ultrasound-guided biopsy | Confirm diagnosis | Adenocarcinoma with small crowded glands |
| Bone scan, MRI | Stage and assess metastasis | Bone lesions, capsular invasion |
💊 Treatment
Localized Disease
- Radical prostatectomy
- External beam radiation therapy
Advanced/Metastatic Disease
- Androgen deprivation therapy (LHRH agonists or antiandrogens)
- Chemotherapy or immunotherapy (abiraterone, enzalutamide)
📊 Prognosis
- Dependent on Gleason score and stage
- Localized tumors have good survival after surgery
- Metastatic disease often incurable but manageable with hormonal therapy
🧠 Key Takeaways
- Prostate carcinoma is an androgen-dependent malignancy usually arising in the peripheral zone.
- PSA screening allows early detection, but interpretation must consider age and BPH.
- Bone metastases are osteoblastic, producing dense lesions on imaging.
- Combination of surgery, radiation, and hormonal therapy offers best outcomes.