I n this issue of Cancer Cytopathology, Jhala et al. 1 report their expe- rience with endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of a variety of sites, with the majority taken from the lymph nodes and pancreas. The authors reported very high overall sensitivity (96%) and specificity (100%) for EUS-FNA in both small lesions (defined as those measuring ี
2.5 cm) and larger lesions. All organ sites had high accuracy rates, including the pancreas, which is a notoriously difficult area to aspirate and evaluate.
Pancreatic carcinoma is the fifth most common cause of cancer deaths in the Western world and the eighth most common cause of cancer deaths worldwide. In 2004, it is estimated that 31,860 individuals will be diagnosed with pancreatic carcinoma and that 31,270 will die of this disease. 2 The disease is insidious and usually presents with nonspecific symptoms and an advanced stage of disease, either locally advanced surgically unresectable tumor and/or distant metastases. The overall 5-year survival rate is reported to be only 4%. 2 Even with surgical resection with intent to cure, the 5-year survival rate is reportedly at best 15%.
Radiographic evaluation of the pancreatobilliary system is directed at defining the anatomy and detecting abnormalities. A variety of techniques have been developed to better visualize lesions in this area, but the diagnosis of pancreatic carcinoma at an early stage remains a challenge. EUS was introduced into the clinical arena in the early 1980s but did not receive much attention and was not used widely until the 1990s. EUS can define intramural lesions of the gastrointestinal tract; is useful in staging tumors; and can visualize adjacent structures, including the lymph nodes, pancreas, spleen, liver, and adrenal glands. The enhanced resolution is, in part, from the proximity of the transducer to the organ examined. Through the esophagus, EUS can help to define the location of mural masses, stage esophageal carcinoma and lung carcinoma, and evaluate mediastinal lesions. At the opposite end of the gastrointestinal tract, EUS has become a useful tool for staging rectal carcinoma. A great deal of the work in endoscopic ultrasonography has been directed toward imaging the pancreas. EUS can overcome many of the limitations of transabdominal ultrasound, such as fat and gas, in evaluating the pancreas. There is published evidence that EUS can detect small pancreatic tumors and neuroendocrine neoplasms that are not detectable by computed tomography (CT), spiral CT, conventional ul-
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