The Ki-67 antigen in primary human melanomas —its relationship to mitotic rate and tumor thickness and its stability

✍ Scribed by H. Ostmeier; L. Suter

• Publisher: Springer-Verlag
• Year: 1989
• Tongue: English
• Weight: 545 KB
• Volume: 281
• Category: Article
• ISSN: 0340-3696
• DOI: 10.1007/bf00456388

✦ Synopsis

We investigated whether two parameters of proliferative activity -mitotic rate and Ki-67 positive cells -are interchangeable. The mitotic rate was assessed on paraffin-embedded sections, Ki-67 positive cells were immunohistologically determined in frozen tissue. A poor correlation (correlation coefficient r = 0.57) was found between both parameters. The proliferative activity was often not homogeneously distributed in the tested tumors. However, this is a major reason for the observed difference only in thin melanomas ( < 1.5 mm) as seen by comparison of tumors with homogeneous and inhomogeneous proliferative activity. We assume that arrest of cells in different stages of the cell cycle -variable from melanoma to melanoma -is the major reason for the observed discrepancy between mitotic rate and Ki-67 positive cells in tumors of 1.5 mm and thicker. The mean number of Ki-67 positive cells increased with tumor thickness. The stability of the Ki-67 antigen towards freezing, thawing, and formalin was studied.