Yonsei Med J.  1974 Jun;15(1):27-42. 10.3349/ymj.1974.15.1.27.

Ultrastructure of Tumor Cell Borders and Its Value in Differentiation of Anaplastic Tumors

• Kim CS
• Lee YB

• KMID: 687682
• DOI: http://doi.org/10.3349/ymj.1974.15.1.27

Abstract

Ultrastructural studies of cell surface and intercellular junctions disclose specialized structures in epithelial cells, endothelial, cardiac muscle and mesothelial cells, and in neoplastic conditions the cell surface and borders may be modified. Present studies were intented to investigate whether there are sufficient differences of cell borders among various tumors of different tissue origin, whereby the nature of tissue origin might be delineated by electron microscopic examination in tumors undeterminable by light microscopy alone. A total of 35 cases of tumors: 23epithelial, 2 smooth muscle, 2 hematopoietic tissue, 2 malignant melanomas, 2 metastatic and 4 undifferentiated, were examined both by light and electron microscopy. In epithelial tumors, desmosomes and basal membrane were constant findings, and microvilli were found only in glandular epithelial tumors. In smooth muscle and hematopoietic tissue tumors, pinocytotic vesicles were prominent, but no junctional apparatus was found except an occasional gap junction. As the tumor became more malignant, there was widening of intercellular spaces, increased cytoplasmic process, decrease of desmosome and less interdigitation. Four cases of undifferentiated tumors showed distinct desmosomal structures in two cases to suggest epithelial origin, the characteristics of fibroblasts in one case, and a preponderance of mesodermal nature in l case of sarcoma botryoides. With these findings, it is thought that there are sufficient differences of cell bordering among epithelial, mesodermal and hematopoietic tissue tumors, and this difference can be applied to aid in differential diagnosis of anaplastic tumors by electron microscopy.