[Blue nevus on the mucosa of the uterine cervix].

Blue nevus of the uterine cervix is a rare benign tumor. It is found occasionally together with the other diseases. In the recent years, 4 cases of blue nevus of the uterine cervix have been found all positive by Masson-Fontana stain. The tumor was very small with no hard mass or protrusion above the mucosa, coloring from light to dark grey. After the sample is fixed, the blue nevus hardly differs from bleeding grossly. Blue nevus of the uterine cervix usually occurs on the mucosa. Approximately, it is similar to the skin nevus under the microscope. There was varying amount of melanin granules in the interstitial cells. The nevus cells were spindle, fibroid, round or large swelling in shape, with the longitudinal axis parallel to the surface. The column formed by the blue nevus cells was often parallel to surface of the mucosa. No mitosis was observed.