The Authors, on the basis of a case of giant spleen cyst with positive tumoral markers, analyse some epidemiological and clinical aspects related to splenic non parasitic cysts. They affirm the priority of the conservative surgery, whenever possible, followed by an appropriate follow-up, although in this case their therapeutic choice was radical, due to the lack of residual parenchyma. In accordance with the data of several publications, as well as on the basis of the results obtained, the conservative approaches have been reevaluated, above all in view of the modern findings related to the function of the spleen. The conservative approach cannot be carried out in the following cases: neoplastic diseases, increase of the tumoral markers serum levels, total involvement of the splenic parenchyma by cysts.