What are the implications and management of a 1.1 centimeter (cm) T2 hypoattenuating lesion within the left corpus cavernosum?

Management of 1.1 cm T2 Hypoattenuating Lesion in Left Corpus Cavernosum

This lesion requires urgent urological evaluation with MRI imaging to characterize the mass and determine if surgical excision is necessary, as T2 hypoattenuating lesions in the corpus cavernosum can represent hemangiomas, thrombosis, or rarely malignancy.

Immediate Diagnostic Approach

Clinical Assessment

• Document the exact location (proximal vs. distal corpus cavernosum), presence of pain, history of trauma, sexual activity-related onset, or spontaneous occurrence 1, 2
• Assess for erectile function changes, penile deformity, palpable masses, or signs of infection 1
• Obtain detailed history regarding recent perineal trauma, forced manipulation of erect penis, or blunt injury, as these account for the majority of corpus cavernosum pathology 3, 4

Laboratory Workup

• Complete blood count to evaluate for elevated white blood cells suggesting infection or inflammatory process 2
• Coagulation studies (PT/INR, aPTT) to assess for underlying thrombotic disorders, particularly if thrombosis is suspected 5, 2
• Urinalysis to exclude urethral involvement 2

Imaging Protocol

MRI Characteristics to Evaluate

• MRI with and without contrast is the gold standard for characterizing corpus cavernosum lesions, as it clearly demonstrates extent, deep extension, and relationship to surrounding structures 6
• T2-weighted sequences are critical: hemangiomas show high signal intensity, while thrombosis appears as hypoattenuating lesions 6, 2
• Assess tunica albuginea integrity and evaluate for bilateral involvement 2
• Color Doppler ultrasound can serve as an adjunct to assess vascular flow patterns and guide potential biopsy if malignancy is suspected 7, 2

Differential Diagnosis Considerations

Most Likely Etiologies Based on Imaging

• Partial priapism/segmental thrombosis: Presents as hypoattenuating lesion in proximal corpus cavernosum, often with perineal pain 5, 2
• Hemangioma: Shows high T2 signal (not hypoattenuating), but can have variable appearance; requires contrast enhancement pattern assessment 6
• Post-traumatic hematoma: History of trauma with hypoattenuating appearance; may resolve spontaneously 3, 2
• Penile malignancy: Rare but must be excluded, particularly if lesion involves corpora cavernosa with depth of invasion 1

Management Algorithm

If Thrombosis/Partial Priapism (Most Likely Given T2 Hypoattenuation)

• Conservative management with NSAIDs is appropriate for recent-onset (<2 weeks) partial priapism without trauma 2
• Follow-up ultrasound at 10-14 days to document resolution; most cases resolve completely with conservative therapy 2
• Anticoagulation is NOT routinely indicated unless underlying thrombophilia is identified 5, 2

If Hemangioma or Vascular Malformation

• Surgical excision is recommended if the lesion causes symptoms, erectile dysfunction, or has uncertain malignant potential 6
• MRI clearly delineates surgical margins and extent of deep extension into corpus cavernosum 6

If Traumatic Rupture/Hematoma

• Immediate surgical exploration is indicated for acute rupture with clinical signs (penile deviation, hematoma, "popping" sound history) 3, 4
• Surgical approach: Use semicircumferential distal incision for distal lesions; direct approach over palpable defect for proximal lesions 3
• Delayed presentation (>5 weeks) may preclude successful irrigation; surgical debridement may be required 5

If Malignancy Suspected

• Biopsy (punch, excisional, or incisional) is mandatory to establish histologic diagnosis before definitive treatment 1
• Staging with CT chest/abdomen/pelvis and inguinal lymph node assessment if penile cancer confirmed 1, 7
• Surgical margins of 5-10 mm are adequate for localized penile malignancies 1

Critical Pitfalls to Avoid

• Do not delay imaging beyond 48-72 hours if acute traumatic rupture is suspected, as delayed surgical repair increases complication rates (fibrous plaques, penile curvature) from 10% to 25-30% 3, 4
• Do not assume benign etiology without tissue diagnosis if the lesion persists beyond 2 weeks or shows atypical imaging features 1, 2
• Do not perform blind aspiration without imaging guidance, as this may complicate subsequent surgical management 7
• Bilateral involvement occurs in only 2-3% of cases but must be assessed, as it changes surgical approach 3

Follow-Up Protocol

• Clinical and ultrasonographic reassessment at 10-14 days for conservatively managed lesions 2
• Complete resolution should occur within 2 weeks for thrombotic/inflammatory lesions; persistence mandates urological referral for biopsy 2
• Long-term erectile function assessment at 3 and 6 months post-treatment to identify delayed complications 3, 4