Comparison between echo-guided fine-needle aspiration cytology and microhistology in diagnosing pancreatic masses

Echo-guided fine-needle aspiration biopsy of pancreatic masses is a well-established diagnostic procedure. However, there is no consensus as to the superiority of cytology or microhistology. We compared the results of cytology and microhistology in 50 consecutive patients who underwent fine-needle aspiration biopsy for pancreatic masses. Aspirates were positive for malignant disease in 42 patients; the other eight had chronic focal pancreatitis. In the 42 cases of cancer, cytology provided conclusive results in 40 (95.2%); sampling was inadequate in two. Microhistology proved accurate in 30 cases (71.4%); insufficient tissue was obtained in 12, giving a statistically significant difference in favor of cytology (P < 0.01). In the eight patients with benign disease both techniques ruled out malignancy; in five microhistology gave further indications confirming suspected chronic pancreatitis (fibrosis, lymphocyte and histiocyte-cell infiltrate). Our results show that cytology is the method of choice in diagnosing pancreatic carcinoma. Microhistology can be a useful adjunct in patients with suspected chronic pancreatitis.