Detection of pancreatic metastases by EUS-guided fine-needle aspiration

Background: Metastases to the pancreas are usually found incidentally. Tiss ue diagnosis is imperative because imaging alone is incapable of differenti ating them from primary pancreatic tumors. This study tested whether it is possible to differentiate metastases from other focal pancreatic lesions by using EUS-guided fine-needle aspiration (EUS-FNA) for cytodiagnosis. Methods: One hundred fourteen consecutive patients (mean age 61 years) with focal pancreatic masses, detected on CT, underwent EUS-FNA by using a line ar-array echoendoscope and 22-gauge needles. Results: Adequate specimens were obtained from 112 lesions. Carcinomas were identified in 68 cases (60.7%), 56 (50%) of pancreatic origin and 12 (10.7 %) from distant primary tumors. The metastases were all located in the head and body of the pancreas and measured 1.8 to 4.0 cm. The echo-texture was heterogeneous or hypoechoic in all cases and resembled that of primary tumo rs. Six of the 12 patients with metastatic disease had a prior diagnosis of cancer (breast, 3; renal cell, 2; salivary gland, 1), 4 of them with a rec urrence and 2 with a second carcinoma metastasizing to the pancreas. Six pa tients without a prior diagnosis of cancer had metastases from renal cell, colonic, ovarian, and esophageal carcinomas; one metastasis was from an unk nown primary and another was from a malignant lymphoma. These findings infl uenced the therapeutic strategy in 8 patients who underwent nonsurgical pal liation. There were no complications. Conclusions: Pancreatic metastasis is an important cause of focal pancreati c lesions, but the EUS features are not diagnostic. Simultaneous EUS-FNA al lows cytodiagnosis and can have a decisive influence on the selection of ap propriate therapeutic strategies.