Primary Kaposi's sarcoma of the heart in non-immunodeficient patient: case report and literature review.

We present a case of Kaposi's sarcoma (KS) of the heart in a 45-year-old non-immunodeficient woman with symptoms of pericardial effusion and cardiac tamponade. Computed Tomography (CT) coronary angiography and transesophageal echocardiography (TEE) showed a low-density tumorous mass (50 mm diameter) at the level of auricle of the right atrium spreading towards the superior vena cava, floating in the cavity of the right atrium. On histological examination, the tumor consisted of fibrovascular connective tissue with areas of necrosis and hemorrhage. Fibrous septae contained different sized thin walled capillary type blood vessels and lymphangioma-type vascular spaces. Vascular spaces were surrounded by extravasated erythrocytes, deposits of hemosiderin and sparse lymphoplasmacytoid infiltrates. On the periphery of tissue fragments and around vascular spaces, there was a cellular kaposiform proliferation of the spindled cells. Slit-like spaces between spindle cells contained erythrocytes. Nuclear pleomorphism of the spindled cells was minimal. Few mitotic figures were present. Spindle cells were Vimentin, CD34 and CD31 positive. More than 10 % of spindled cells were Ki67 positive. This characteristic histology and immunohistochemistry is consistent with Kaposi's sarcoma. Patient has no history of other malignancies and no other primary tumor was detected. Patient also was negative for HIV infection. There are only 10 documented cases of primary Kaposi's sarcoma of the heart in non-immunodeficient patients reported in the current medical literature. Our report is the first case in which imaging, histology and immunohistochemistry data are available.

Wnt signaling in prostate development and carcinogenesis.

BACKGROUND: The Wnt signaling pathway is crucial for cell fate decisions, stem cell renewal, regulation of cell proliferation and differentiation. Deregulated Wnt signaling is also implicated in a number of hereditary and degenerative diseases and cancer. METHODS AND RESULTS: This review highlights the role of the Wnt pathway in the regulation of stem/progenitor cell renewal and prostate gland development and how this signaling is altered in prostate cancer. Recent evidence suggests that Wnt signaling regulates androgen activity in prostate cancer cells, enhances androgen receptor expression and promotes the growth of prostate cancer even after androgen ablation therapy. There is also strong evidence that Wnt signaling is enhanced in androgen-ablation resistant tumors and bone metastases. CONCLUSIONS: Further study of the modulators of this pathway will be of therapeutic relevance as inhibition of Wnt signaling may have the potential to reduce the self-renewal and aggressive behaviour of prostate cancer while Wnt signaling activation might enhance stem cell activity when tissue regeneration is required.