A medical apparatus and method of preparing one or more cell blocks. The medical apparatus comprises at least one elongate tubular body having a proximal end and a distal end and a filter membrane disposed between the proximal end and a distal end of the elongate tubular body. The filter membrane, which can include alignment features and structural features to engage the tubular body, and/or cover, is sectionable. Additionally, in some embodiments a second elongate tubular body is provided which telescopingly receives at least a portion of the first elongate tubular body. In other embodiments, a support member is provided for engaging the filter membrane and positioning the filter membrane at a midpoint of the elongate tubular body during centrifuging.