Subungual Pigmentation in a 30-Year-Old Asian Male: Hematoma vs. Melanoma Differential

Case at a Glance

A 30-year-old Asian male presents with asymptomatic dark pigmentation under his great toenail discovered incidentally during routine hygiene. No recall of trauma, raising concern for possible subungual melanoma versus hematoma.

Patient's Story

The patient noticed a dark discoloration beneath his toenail while showering. He denied any pain, tenderness, or functional impairment. Despite thorough questioning, he could not recall any recent trauma to the affected digit. Given his Asian ethnicity and the location of the lesion, he became concerned about the possibility of subungual melanoma after researching online.

Initial Assessment

Physical examination revealed a well-demarcated dark pigmented area beneath the nail plate of the great toe. The lesion was non-tender to palpation, and there was no associated nail deformity, inflammation, or lymphadenopathy. The surrounding skin and nail fold appeared normal.

The Diagnostic Journey

The primary differential diagnosis included subungual hematoma versus subungual melanoma. Given the patient's ethnicity (Asian populations have higher rates of acral melanoma) and absence of recalled trauma, careful monitoring was recommended. The consulting physician explained the growth pattern method for differentiation - measuring the distance from the cuticle to the lesion and tracking nail growth over time.

Final Diagnosis

Probable subungual hematoma with recommendation for serial monitoring using nail growth measurement technique.

Treatment Plan

Conservative management with serial observation. Patient instructed to measure the distance from the cuticle to the closest edge of the pigmented area in millimeters. Follow-up assessment planned at 2-month intervals to evaluate for outward migration of the lesion consistent with nail growth (expected 4mm progression over 2 months for toenails).

Outcome and Follow-up

Patient counseled on warning signs requiring immediate evaluation and given clear instructions for self-monitoring. Plan for dermatology referral if lesion fails to migrate appropriately with nail growth or if any concerning features develop during observation period.