Cell Block Optimization: A Comparative Study of Quality Variables in 4 Different Cell Block Methods.

Objective: The cell block (CB) is an important adjunct to cytological preparations in diagnostic cytopathology. Optimizing cellular material in the CB is essential to the success of ancillary studies such as immunohistochemistry (IHC) and molecular studies (MS). Our aim was to identify which CB method was most suitable in a variety of specimen types and levels of cellularity.

Clonality assessment and clonal ordering of individual neoplastic crypts shows polyclonality of colorectal adenomas.

Background & Aims: According to the somatic mutation theory, monoclonal colorectal lesions arise from sequential mutations in the progeny of a single stem cell. However, studies in a sex chromosome mixoploid mosaic (XO/XY) patient indicated that colorectal adenomas were polyclonal. We assessed adenoma clonality on an individual crypt basis and completed a genetic dependency analysis in carcinomas-in-adenomas to assess mutation order and timing.