Plantar melanoma: results of treatment in three population groups.

BACKGROUND

The frequency of plantar melanoma varies widely in different population groups. The plantar surface is an infrequent site in white persons but is common in the black population. The effect of ethnicity on melanoma of the plantar surface has not previously been well defined. The aim of this study was to analyze the results of a standard protocol of treatment of melanoma of the sole in 3 homogeneous population groups treated during a 15-year period at a university referral hospital.

METHODS

A retrospective analysis of 1403 consecutive patients with melanoma treated between 1977 and 1991 was performed. Eighty-five patients (35 black, 25 white, and 16 of mixed ancestry) had primary cutaneous melanoma involving the sole of the foot.

RESULTS

Acral lentiginous melanoma was the most common histogenetic type and occurred in 49 patients. Significantly more black patients (20 of 35) had metastatic disease compared with white patients or groups with mixed ancestry (P < .05). The Breslow depth was significantly more advanced in black patients (7.1 mm) with stage I disease than in white patients (3.3 mm) or those of mixed ancestry (3.6 mm) (P < .05). The 5-year survival rate was 60% for white patients, 26% for black patients, and 24% for those of mixed ancestry.

CONCLUSIONS

Black patients were seen more frequently with advanced local disease, and nearly half had disseminated disease. Those of mixed ancestry had a histogenetic type resembling that of black patients, but the Breslow depth of penetration was similar to that of white patients. Education programs to heighten awareness of both patient and physician are required to enable earlier diagnosis and improve outcome.