Gastroenterology
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Conventional therapies for ulcerative colitis and Crohn's disease (CD) include aminosalicylates, corticosteroids, thiopurines, methotrexate, and anti-tumor necrosis factor agents. A time-structured approach is required for appropriate management. Traditional step-up therapy has been partly replaced during the last decade by potent drugs and top-down therapies, with an accelerated step-up approach being the most appropriate in the majority of patients. ⋯ Common mistakes in conventional therapy include overprescription of mesalamine for CD; inappropriate use of steroids (for perianal CD, when there is sepsis, or for maintenance); delayed introduction or underdosing with azathioprine, 6-mercaptopurine, or methotrexate; and failure to consider timely surgery. The paradox of anti-tumor necrosis factor therapy is that although it too is used inappropriately (when patients have sepsis or fibrostenotic strictures) or too frequently (for diseases that would respond to less-potent therapy), it is also often introduced too late in disease progression. Conventional drugs are the mainstay of current therapy for inflammatory bowel diseases, but drug type, timing, and context must be optimized to manage individual patients effectively.
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Review
Role of somatostatins in gastroenteropancreatic neuroendocrine tumor development and therapy.
The incidence and prevalence of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) have increased in the past 20 years. GEP-NETs are heterogeneous tumors, in terms of clinical and biological features, that originate from the pancreas or the intestinal tract. Some GEP-NETs grow very slowly, some grow rapidly and do not cause symptoms, and others cause hormone hypersecretion and associated symptoms. ⋯ Peptide receptor radiotherapy has significant antitumor effects, increasing overall survival times of patients with tumors that express a high density of SSTRs, particularly SSTR2 and SSTR5. The multi-receptor somatostatin analogue SOM230 (pasireotide) and chimeric molecules that bind SSTR2 and the dopamine receptor D2 are also being developed to treat patients with GEP-NETs. Combinations of radioactive labeled and unlabeled somatostatin analogues and therapeutics that inhibit other signaling pathways, such as mammalian target of rapamycin (mTOR) and vascular endothelial growth factor, might be the most effective therapeutics for GEP-NETs.
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A variety of noninvasive molecular approaches to colorectal cancer screening are emerging with potential to improve screening effectiveness and user-friendliness. These approaches are based on the sensitive assay of molecular markers in stool, blood, and urine samples. ⋯ Validation of these technologies in average-risk populations are needed to establish their role for general colorectal cancer screening. This review addresses the biological rationale, technical advances, recent clinical performance data, and remaining issues with molecular screening for colorectal cancer.