HEMATOLOGY-ONCOLOGY
PROSTATE CANCER
Epidemiology and risk factors (NEJM 2003;349:366)
• Most common cancer in U.S. men; 2nd most common cause of cancer death in men
• Lifetime risk of prostate cancer dx ~16%; lifetime risk of dying of prostate cancer ~3%
• More common with ↑ age (rare if <45 y), in African Americans and if FHx
• ↑ risk w/ BRCA2 (4.7) and BRCA1 (1.8) (JNCI 1999;91:1310 & 2002;94:1358)
Clinical manifestations (usually asymptomatic at presentation)
• Obstructive sx (more common with BPH): hesitancy, ↓ stream, retention, nocturia
• Irritative sx (also seen with prostatitis): frequency, dysuria, urgency
• Periprostatic spread: hematuria, hematospermia, new-onset erectile dysfunction
• Metastatic disease: bone pain, spinal cord compression, cytopenias
Screening (NEJM 2012;367:e11)
• Digital rectal exam (DRE): size, consistency, lesions
• PSA: 4 ng/mL cut point neither Se nor Sp; can ↑ with BPH, prostatitis, acute retention, after bx or TURP, and ejaculation (no significant ↑ after DRE, cystoscopy); 15% of men >62 y w/ PSA <4 & nl DRE have bx-proven T1 cancer (NEJM 2004;350:2239)
• Per American Cancer Soc. men ≥50 y (or ≥ 45 y if African-Am or FHx) should discuss PSA screening w/ their MD; USPSTF rec. against screening in asx males (no reduction in prostate cancer-related mortality) (NEJM 2009;360:1310; Annals 2012;157:120)
Diagnostic and staging evaluation
• Transrectal ultrasound (TRUS) guided biopsy, with 6–12 core specimens
• Histology: Gleason grade (2–10; low grade ≤6) = sum of the differentiation score (1 = best, 5 = worst) of the 2 most prevalent patterns in the bx; correlates with prognosis
• Imaging: to evaluate extraprostatic spread bone scan: for PSA >10 ng/mL, high Gleason grade or clinically advanced tumor abdomen-pelvis CT: inaccurate for detecting extracapsular spread and lymph node mets endorectal coil MRI: improves assessment of extracapsular spread
Prognosis
• PSA level, Gleason grade and age are predictors of metastatic disease
• In surgically treated Pts, 5-y relapse-free survival >90% if disease confined to organ, ~75% if extension through capsule, and ~40% if seminal vesicle invasion
• PSA doubling time, Gleason, & time to biochemical recurrence predict mortality following recurrence. For local recurrence following RP, salvage RT may be beneficial if low PSA.
• Metastatic disease: median survival ~24–30 mo; all become castrate resistant (in 15–20% discontinuation of antiandrogens results in paradoxical ↓ in PSA)
• Long-term consequences of antiandrogen therapy include osteoporosis
Prevention
• Finasteride and dutasteride ↓ total prostate cancers detected by bx, but ↑ number of high Gleason grade tumors (NEJM 2003;349:215 & 2010;362:1192)