StatusThe thesis was presented on the 27 March, 2007
Approved by NCAA on the 19 April, 2007
Abstract– 0.28 Mb / in romanian
Early metastasis is one of the main causes of expressed aggressivity of ovarian cancer. However, the factors which determine such aggressive behavior are still not completely clear. The purpose of this study was revealing of histological cytological, and electron-microscopic peculiarities of peritoneal metastasis of ovarian cancer. For this purpose, using histological method, it was studied the post operational material of 226 patients, and in a part of them was examined ovarian carcinoma and its metastasis using cytological, immunohistochemical, and electron-microscopical methods.
Based on received data, in ovaries most frequently develops the serous carcinoma (77% of epithelial tumors) and rarely were found the mucinous (15% cases), endometrioid (4,5%), mezonephroid carcinomas (3,5%). The pointed out histological forms of cancer often affect both ovaries and frequently metastasize into periotoneum. The serous carcinoma, for example, was settled bilaterally in 67% cases and had spreaded into the peritoneum in 61% cases.
In carcinomas, comparative to normal ovarian surface epithelium, was increased the differentiation of epithelial cells, but in metastasis the differentiation was significantly increased and was manifested by formation of mature specialized intercellular junctions and high specialized apical structures-cilia. However, in spate of expressed differentiation of epithelial cells in ovarian carcinoma and its metastases, the subepithelial basal membrane was significantly defected and in many cases was absent under several dozens of cells. These defects were confirmed electron-microscopically and especially immunohistochemically, reflecting data about presence of collagen IV in stromal vessels and its absence in neoplastic epithelial structures. These defects of epitelio-stromal junction may facilitate the detachment of tumor cells from stroma and their passing into peritoneal liquor. The presence of cilia, having the movement function, promotes probably the fast spread of neoplastic cells into peritoneal space. The presence of ovarian cancer cells into peritoneal liquor could be revealed by cytological method, but in this examinatio it is necessary to differentiate neoplastic cells from desquamated mezothelial cells. One of the criteria of such differentiation is the presence of defects in the cancer cell cytoplasm, reflecting, possibly, poor development of their cytoskeleton. The inoculation of small groups of tumor cells was observed into the peritoneum milk spots, presented as the lymphoid structures settled on draining ways of peritoneal liquor. In metastasis of large dimensions, the stroma was more developed than in the primary tumors and the stroma-parenchyma correlation constitutes respectively 3:2 and 1:3. It is paradoxical a such development of fibrous stroma on the tissue background, mostly being constitued by adipose cells.
Thus, from the received results we can deduce that in ovarian carcinomas and especially in their peritoneal metastases occur paradoxical changes, one of them is the increasing of cells differentiation. This phenomenon is opposite to majority of other epithelial malignant tumors, which during the neoplastic transformation become less differentiated than the epithelium of their origin.