Intraoperative and on-site cytopathology consultation: utilization, limitations, and value.

The intraoperative and on-site cytopathology can be successfully performed with a number of smear preparations. Specimen concentration technique is the preferred method. The Romanowsky stain such as Diff Quik used in our laboratory is economical, convenient, reproducible, and quick. This can be at times combined with Ultrafast pap or other rapid stains, which provide good nuclear details. Such evaluations are most valuable in the staging of epithelial tumors and primary diagnosis of a number of central nervous system lesions. On-site and intraoperative diagnoses help triage the specimens for additional studies. This reduces the turn around time and makes the procedure cost-effective and beneficial to the patient. An awareness of the "normal" adjacent structures and familiarity with the cytomorphology of the specimens in comparison to the exfoliative specimens is critical in developing a cytopathology service with high degree of sensitivity and specificity.