[A case of pancreatic neuroendocrine tumor with excessively-advanced liver metastasis treated with S-1/GEM combination chemotherapy plus the long-acting somatostatin analogue octreotide].

A 41-year-old woman who had a pancreatic tail tumor and multiple liver tumors was referred to our hospital. The results of abdominal US, CT and MRI, and histopathological and immunohistochemical findings of the liver tumor biopsy revealed a pancreatic neuroendocrine tumor with excessively-advanced liver metastasis. We treated her with S-1/gemcitabine combination chemotherapy plus long-acting somatostatin analogue octreotide, which produced tumor stabilization and good quality of life for 7 months, and survival time of 15 months. Although the tumor was diagnosed as a poorly differentiated endocrine carcinoma, this therapy was suggested to be effective in this case.

[Carcinogenesis of Barrett's esophagus].

Barrett's esophagus is a premalignant condition and remains the number one risk factor for developing adenocarcinoma. Gastro-esophageal reflux disease is a strong risk factor for both esophageal adenocarcinoma and the precancerous lesion Barrett's esophagus. Both of these conditions are related to the reflux of acid and bile into the esophagus. This results in inflammation and cell damage which initiates a sequence of events termed the metaplasia-dysplasia sequence in which the squamous epithelium is replaced by columnar epithelium exhibiting increasing degrees of dysplasia and overt malignancy. The underlying disease mechanisms remain unclear, but tumor suppression genes (p53, p16, APC) and, oncogenes (K-ras, cyclin D1, c-erb-2) seem to cause the malignant transformation of Barrett's esophagus, and the genetic or epigenetic alterations of these genes have been reported.