Narrow band imaging endoscopy for detection of precancerous lesions of upper gastrointestinal tract.

Gastric cancer (GC) is an important health problem despite the advances in surgery and chemotherapy and although the incidence is decreasing, GC is still considered the second most common cause of deceases produced by cancer. Survival rates in gastric cancer are low, mainly because most patients are often diagnosed in late stages. The current interest in the diagnostic of GC is the detection of early gastric cancer. Advances in high-resolution endoscopic techniques such as narrow band imaging (NBI) allow the detection of early precancerous lesions like polyps or metaplastic mucosa. Performing only white light imaging endoscopy in order to detect gastric cancer can lead to omission or misdiagnose of a considerable number of early gastric cancers. NBI endoscopy associated with other high-resolution examinations is viable in detecting early gastric cancer, though few studies also indicate that the endoscopist's expertise plays an important factor as well.

Narrow band imaging with near-focus mode for colorectal polyps' characterization.

Conventional white light endoscopy is far from being an ideal tool to detect, characterize, and confirm the nature of colorectal lesions in order to indicate targeted biopsies or polyp resections only when necessary. Minimally invasive imaging techniques have gradually emerged to reveal previously unseen abnormalities to the operator during endoscopic examination. In this respect, technology and applications of narrow band imaging (NBI) are rapidly evolving. Magnification using NBI with near-focus mode has been introduced recently to enable closer examination under the control of a single button. The aim of this article is to offer an in-depth overview of this topic with emphasis on colorectal polyps through a literature review by using PubMed search tools including full-text articles, up-to-date guidelines and recent abstracts with obvious conclusions.

Utility of endoscopic ultrasound multimodal examination with fine needle aspiration for the diagnosis of pancreatic insulinoma - a case report.

Insulinomas are benign insulin-secreting neuroendocrine tumors originating in the pancreatic beta cells. Symptoms are caused by hypoglycemia and clinical diagnosis is based on establishing their relationship to fasting, usually via a fasting test. The most conclusive imaging tests are endoscopic ultrasound (EUS) and CT. Surgery is the treatment of choice. A 33 year old male presented with a 2-year history of hunger which had intensified in the previous 6 months with added accompanying symptoms, culminating with an acute episode - loss of consciousness and seizures - which resolved after administering i.v. glucose. A fasting test was performed, with results suggestive for an insulinoma. Dual-phase CT showed a mass in the tail of the pancreas but no contrast enhancement. EUS was used for further assessment: B-mode showed a hypoechoic focal mass with a cystic component, on contrast enhancement the pattern was hypovascular, and elastography showed soft tissue. EUS fine needle aspiration (FNA) was performed and the immunohistochemistry (IHC) assay was conclusive for a neuroendocrine tumor of the pancreas. Treatment consisted of caudal pancreatectomy, with no recurrence after 1-year follow-up. Although this case started with a classic clinical presentation of an insulinoma, imaging studies related to tumor vascularization raised doubts about the actual diagnosis. Nevertheless, multimodal EUS assessment with FNA was considered to be the most appropriate diagnostic technique for detection, characterization and staging of the mass. EUS findings together with the IHC assay were able to offer the definite diagnosis of a benign neuroendocrine tumor and allowed us to refer the patient for appropriate treatment.