Nuclear planimetry and DNA flow cytometry of verruga peruana.

Verruga peruana is a vascular hyperplasia that is sometimes histologically mistaken for a malignant neoplasm. An infiltrative pattern with nuclear pleomorphism and mitoses is prominent in some lesions. From a series of lesions of verruga peruana, we selected five atypical lesions, two of them closely resembling epithelioid angiosarcoma. We used histologic criteria as well as morphometry and flow cytometry to further characterize the atypical features of the lesions. Histology and morphometry evidenced marked nuclear pleomorphism. Flow cytometry failed to reveal aneuploidy and disclosed about 10% of the cells to be in the S, G2 and M phase.