Angiogenesis correlates with metastasis in melanoma.

BACKGROUND

Angiogenesis has been correlated with melanoma progression, but its role in melanoma metastasis is unclear.

METHODS

To determine whether angiogenesis correlates with the presence of melanoma metastases, we compared the number of microvessels in the primary melanomas of 12 patients presenting with metastases to those of 13 patients without metastases. Patient groups were matched for gender, age, tumor depth, and histological type and anatomical location of the primary melanoma. Microvessels were stained with factor VIII antibody and counted.

RESULTS

Microvessel counts were significantly greater for the metastatic than the nonmetastatic melanomas (51.63+/-14.95 vs. 24.86+/-8.415; P < .0001). One hundred percent of the metastatic melanomas had a mean microvessel count of > or = 37, whereas only 8% of the nonmetastatic melanomas had a mean microvessel count of > or = 37 (sensitivity = 1.00, specificity = .92). Interestingly, patients with lymph node metastases had significantly lower microvessel counts than did patients with distant metastases (42.00+/-3.482 vs. 58.50+/-16.40; P < .05), and significantly higher microvessel counts than did patients without metastases (42.00+/-3.482 vs. 24.86+/-8.415; P < .001).

CONCLUSIONS

An increased number of microvessels in the primary tumors of patients with melanoma correlates with the simultaneous presence of metastases. This suggests that angiogenesis may be important in the process of melanoma metastasis.