A 65-year-old man comes to the office due to 4 weeks of persistent epigastric pain and nausea. The pain is constant and does not improve or worsen with activities, position, or diet. The patient lost approximately 4.5 kg (9.9 lb) over this period. He has no fever, vomiting, constipation, or diarrhea. He was diagnosed with type 2 diabetes mellitus 6 months ago, which is controlled with a low-carbohydrate diet. The patient has never had surgery and has no other chronic medical conditions. He has a 45-pack-year history of smoking. He does not use alcohol or illicit drugs. Temperature is 36.5 C (97.7 F), blood pressure is 122/72 mm Hg, pulse is 68/min, and respirations are 16/min. BMI is 24 kg/m². Mucous membranes are moist. No lymphadenopathy is present in the cervical or axillary chains. Bowel sounds are present, and the abdomen is soft with mild epigastric tenderness to deep palpation. No hepatosplenomegaly or shifting dullness is present. The remainder of the examination is normal. Complete blood count, serum chemistry, and liver function studies is all normal except a fasting blood sugar of 130 mg/dL. Which of the following is the most appropriate next step in management of this patient?

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This patient's older age, weight loss, constant epigastric pain, smoking history, and recent diagnosis of diabetes mellitus (DM) raise strong concern for pancreatic cancer, the fourth most common cause of cancer-related death in the United States. Major risk factors include cigarette smoking, chronic pancreatitis, and disorders of glucose metabolism such as insulin resistance and DM. Approximately 25% of patients with pancreatic cancer are diagnosed with DM <2 years prior to discovery of the tumor. In particular, atypical DM (eg, DM presenting in a thin, older patient) should raise suspicion for pancreatic cancer, particularly when accompanied by other suggestive findings (eg, pain, weight loss). It is unclear whether DM promotes carcinogenesis or whether DM occurs as a consequence of a paraneoplastic syndrome from adrenomedullin secretion, leading to pancreatic beta cell dysfunction. Screening for pancreatic cancer is not recommended in adults with new-onset diabetes because the incidence of DM is much greater than pancreatic cancer. However, those who have symptoms of pancreatic cancer such as gnawing, constant epigastric pain and weight loss require further evaluation with CT scan of the abdomen. Abdominal ultrasound is used in the initial evaluation of patients with painless jaundice, anorexia, or weight loss. However, it is not the preferred modality for screening patients who have abdominal pain without jaundice; it often misses smaller (potentially resectable) tumors; and it does not delineate tumor extension as well as CT does (Choice A). (Choices C and E) Patients with gastric/duodenal ulcers or gastric tumors often have gnawing epigastric pain that is worse several hours after meals (when the food buffer is cleared). These conditions are generally diagnosed by esophagogastroduodenoscopy followed by Helicobacter pylori stool antigen testing. However, peptic ulcers rarely cause constant epigastric pain or weight loss. Gastric cancer typically causes anemia (due to tumor bleeding into the stomach) and is not linked to recent-onset diabetes mellitus. (Choice D) A nuclear gastric emptying scan can diagnose gastroparesis, which is common in patients with poorly controlled diabetes mellitus and generally presents with postprandial bloating, nausea, and early satiety. Constant abdominal pain would be atypical, and this patient's diabetes mellitus is controlled with diet. Educational objective: Approximately 25% of pancreatic cancer is heralded by a recent (<2 years) diagnosis of diabetes mellitus. Although screening for pancreatic cancer is not recommended for patients with new-onset diabetes mellitus, those who have symptoms (eg, constant abdominal pain, weight loss) of pancreatic cancer should undergo abdominal CT scan. References: Prevalence of diabetes mellitus in pancreatic cancer compared to common cancers. (http://www.ncbi.nlm.nih.gov/pubmed/23000893)

A 65-Year-Old Man Comes to the Office Due to 4