Endoscopic Ultrasound: A Diagnostic and Therapeutic Tool in Pancreatic Lesions

Abstract

Purpose: Endoscopic ultrasound (EUS) has evolved from a simple imaging modality to one that can be used both for diagnostic and therapeutic purposes. The increasing utilization of CT scan of abdomen detects a number of silent pancreatic lesions - both cysts and masses. The ability of EUS to identify the pancreatic lesions that are too small to be identified by CT or MRI and to guide a needle both for biopsy or drainage, gives it a clear advantage over other imaging modalities in investigating pancreatic lesions. The aim of our study was to evaluate the outcome of EUS findings in patients with pancreatic abnormalities on CT or MRI and also to assess the utility of EUS as both a diagnostic and therapeutic modality. Methods: A chart review of all patients who underwent EUS at our hospital for suspected pancreatic pathology as found on CT or MRI of abdomen was conducted over a 3 year period. Pancreatic lesions found on EUS underwent a fine needle aspiration (FNA) and subsequent histopathological studies were followed up. Results: A total of 54 patients had EUS evaluation for pancreatic pathology. The study group comprised of 28 males and 26 females with a mean age of 56.9 years (range 27-79 years). Main indications of EUS in these cases were abnormal CT/MRI findings, suggestive of mass/cyst in the pancreas. *21 out of 54 cases had pancreatic cystic lesions. - 17 out of these cases were found to be simple cysts, of which 12 were drained and 5 cases could not be drained due to blood vessels surrounding the cyst or large cyst size. - 4 cases were found to be complex cysts, of which 3 were biopsied and only 1 was found to be malignant. *15 out of 54 cases showed solid mass lesions, of which 13 had FNA done and 8 were found to be malignant (4 adenocarcinoma; 1 neuroendocrine tumor and 3 were undeterminate). *10 out of 54 cases were evaluated for suspected pancreatic mass and were found to have chronic pancreatitis. *1 out of 54 cases was evaluated for MRI finding of annular pancreas, EUS confirmed this finding with no mass lesion. *7 patients had a completely normal EUS despite a suspected mass on CT/MRI study. Conclusion: EUS guided cystic drainage helped to resolve simple cysts and served as a diagnostic tool for complex pancreatic cysts in majority of the cases. EUS helped in the staging of solid pancreatic lesions and helped to ascertain the histopathological diagnosis. The possibility of using EUS for both diagnostic and therapeutic purpose gives it superiority over other imaging modalities like ultrasound/CT/MRI and MRCP. The disadvantages of EUS are that it needs a great deal of technical expertise, state of the art equipment and the need for IV sedation during the procedure.