I Adenocarcinoma of the Stomach A Epidemiology 1. Comprises 95% of all gastric tumors 2. Fourth most common gastrointestinal (GI) malignancy worldwide 3. Second cause of cancer mortality worldwide (behind lung cancer) 4. Approximately 25,000 cases reported in United States…
I Esophageal Anatomy 1. The esophagus is a muscular pump bordered by two sphincters, the upper esophageal sphincter (UES) and lower esophageal sphincter (LES). Its function is to transport food and liquids in a unidirectional movement, and it possesses no…
I Epidemiology 1. Worldwide, it is estimated that 300,000 people are living with oral cavity and pharynx cancer. Approximately 48,000 head and neck cancers are diagnosed in the United States annually, representing nearly 3% of cancers diagnosed in North America…
I Self-Sufficiency in Growth Signals Mitogens are chemicals that trigger cell mitosis. In contrast with healthy cells, cancer cells have a reduced dependence on mitogens and external growth factors for replication. A Growth Factors 1. Tumor cells and stroma produce…
I Epidemiology of Morbid Obesity A Definitions 1. Overweight—body mass index [(BMI) = weight in kg/height in m 2 ] greater than 25–29.9 2. Obese (Class I)—BMI greater than 30–34.9 3. Severe obesity (Class II)—BMI greater than 35–39.9 4. Morbid…
The spleen is the largest organ of the reticuloendothelial system, responsible for many filtration and host defense mechanisms; however, it is not well understood. It plays a role in many childhood and adulthood hematologic and immunologic disorders and can cause…
I Anatomy A Embryology 1. The pancreas begins as dorsal (from duodenum) and ventral (from hepatic diverticulum) budding from the foregut endoderm at approximately the fifth week of gestation. 2. Both the dorsal and ventral portions of the pancreas possess…
I Overview A Anatomy 1. The appendix develops as a protuberance of the base of the cecum. a. The base is located at the convergence of the teniae coli, and the tip is variably located (e.g., retrocecal, pelvic). b. Blood…
I Anatomy A Rectum 1. The rectum is 12–15 cm in length and extends from the sacral promontory to the levator ani muscles. 2. The teniae coli splay out at the rectosigmoid junction and fuse to form a contiguous smooth…
I Anatomy A General Description 1. The esophagus is an approximately 30-cm-long, muscular tube that begins 15 cm from the incisors at the cricopharyngeus muscle and ends at the gastroesophageal junction (GEJ) along the cardia of the stomach. There are…