Role of Microenvironment in Ovarian Tumourisation

Background. Metastasis is a formidable complication of malignant neoplasms, with therapy not always effective in advanced malignancy. Metastasis is a multistep process involving the cancer cell detachment from primary tumour, intravasation, extravasation and invasion into the target organ. Early metastasis stages are well understood, whilst the impact of tumour microenvironment on the disease progression and advancement remains a matter of debate.

Aim. An immunohistochemical study of the adaptive and reactive properties of greater omentum with metastatic involvement in ovarian cancer.

Materials and methods. We examined greater omentum tissue samples from 40 patients with verifi ed stage 3a and b ovarian cancers. For light microscopy, samples were fi xed in 10 % formalin, dehydrated, paraffi n-embedded and stained with Mayer’s haematoxylin and eosin. Immunohistochemical assays used monoclonal antibodies against CD7, CD4, CD8, CD 68, VEGF, D2-40 and CD44 proteins. Statistical data analysis was performed with Statistica v. 7.0 soft ware.

Results and discussion. Analyses of the greater omentum tissues revealed cases of leucocyte-bank encapsulation of metastatic foci. Higher CD7+ and CD8+ cell counts were observed in encapsulation, possibly influencing the greater omentum reactive and adaptive properties. Higher CD44-expressing cell counts were also detected in greater omentum samples lacking encapsulation. Angiogenesis marker-expressing cells (e.g., VEGF and CD34) predominated in greater omentum tissues lacking leucocyte-bank encapsulation of metastatic foci.

Conclusion. Events in tumour microenvironment may be indicative of a preserved or reduced organ adaptivity, the latter facilitating disease progression.

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