The development of endoscopic ultrasound scanning(EUS) began in the early 1980s with mechanical radial
scanning transducers.1 Despite excellent imaging resolution,it did not become popular until the advent of EUS-guided
fine needle aspiration biopsy (EUS-FNA).

2 EUS-FNA has now matured into a highly valuable method for acquisition of
cytologic specimens. EUS-FNA is not only limited to gastroenterology since the gastrointestinal tract traverses through

3 There is also considerable evidence that, in experienced hands and in combination with an expert cytopathologist, EUS-FNA is able to provide a cytologic diagnosis in between 80 percent and 95 percent of malignant lesions depending on the type of lesion as well as the location, with an overall sensitivity and specificity of 90 percent and 100 percent , respectively, and with a complication rate not different from CT or ultrasound-guided needle aspirations.4-10 In addition, many of the lesions targeted by EUSFNA are either not reachable or visible by other imaging methods due to small size or overlying bony or air-filled structures. Minute lesions down to a size of 5 mm may be imaged and subsequently biopsied by EUS-FNA.11 It is at present evident that specimens obtained by EUS-FNA have a high likelihood of providing representative tissue for diagnosis when other techniques have failed or are not applicable. EUS-FNA, aside from establishing primary diagnosis of malignancy, can also accurately stage patients preoperatively and influence the decision-making process, thereby reducing
the morbidity and mortality of noncurative surgical interventions. Thus, EUS-FNA can replace many other far more invasive and risky diagnostic procedures. However, there are some limitations of the FNA method and, in some cases, more tissue is needed to further classify a lesion such as lymphoma and gastrointestinal stromal tumor. Endoscopic ultrasound-guided tru-cut biopsy (EUS-TCB)
has recently emerged as a method that tries to overcome the limitations of EUS-FNA by providing a core-tissue specimen