Malignant melanomas in black Africans are predominantly located on the lower 
extremities. Since their biological features have not been well focused, we 
studied 28 such cases with special reference to proliferative activity (Ki-67 
expression), p16 and p53 staining, as well as microvessel density, all known to 
be involved in the progression of melanomas among whites. The findings were 
related to clinico-pathological characteristics. The tumours had a median 
thickness of 6.4 mm, ulceration was present in 71%, and vascular invasion in 
36%, indicating the presence of advanced and aggressive melanomas. Further, loss 
of p16 protein expression was found in 50%, and high proliferative activity was 
present (median 41%). In contrast, strong p53 staining was rare (11%), although 
most tumours showed low-level positivity. Angiogenesis, as estimated by 
microvessel density, was significantly associated with vascular invasion (p = 
0.022), supporting its role in the progression of these tumours. Thus, our 
findings indicate that melanomas located on the lower extremities in black 
Africans show several features of aggressiveness; in particular, the 
proliferative activity was high, and p16 alterations was frequent as evidenced 
by loss of protein staining. Our findings also indicated that the diagnosis is 
delayed among black Africans.