Immunocytochemistry as an adjunct to diagnostic cytology.

Immunocytochemistry as a routine ancillary test remains a distant reality for most diagnostic laboratories. Notable barriers to the mass deployment of ICC include: the large variety of specimen preparations, the small specimen size, lack of validation and lack of control specimens. As clinicians constantly strive to answer questions relating to diagnosis, therapy and prognosis with minimally invasive sampling techniques, the cytopathology community must endeavour to adopt ancillary specimen testing by ICC as a core element of diagnostic cytology.