Diagnostic value of processing cytologic aspirates of renal tumors in agar cell (tissue) blocks.

Objective: To adapt a method enabling utilization of most of the harvest from a fine needle aspirate in an effort to improve diagnostic accuracy in the assessment of a renal tumor in a single histologic slide.

Study Design: In a series of 43 renal tumors, 2 fine needle aspirations were performed, 4 smears were prepared after each aspiration for conventional cytology and the remaining aspirate was processed for the improved agar microbiopsy (AM) method. Conventional cytology slides, AM slides and surgical specimens were diagnosed separately, after which the diagnoses were compared.