Pancreatic cancer (PC) has a poor prognosis due to delayed diagnosis. Early diagnosis is the most important factor for improving prognosis. For early diagnosis of PC, patients with clinical manifestations suggestive of PC and high risk for developing PC need to be selected for examinations for PC. Signs suggestive of PC (e.g., symptoms, diabetes mellitus, acute pancreatitis, or abnormal results of blood examinations) should not be missed, and the details of risks for PC (e.g., familial history of PC, intraductal mucin producing neoplasm, chronic pancreatitis, hereditary pancreatitis, or life habit) should be understood. Multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) can be performed for diagnosing PC, but the diagnostic ability of these examinations for PC is limited. Endoscopic diagnostic procedures, such as endoscopic ultrasonography, including fine-needle aspiration, and endoscopic retrograde pancreatocholangiography, including Serial Pancreatic-juice Aspiration Cytologic Examination (SPACE), could be recommended for a detailed examination to diagnose pancreatic carcinoma earlier.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease. PDAC is the fourth leading cause of death in the United States and Japan based on epidemiological data. Early detection of PDAC is very important to improve the prognosis of PDAC. Early detection of pancreatic ductal adenocarcinoma (PDAC) requires further examination after selecting cases with risk factors for the condition, such as family history, hereditary pancreatic carcinoma syndrome, intraductal papillary mucinous neoplasms, or chronic pancreatitis. The Japan Study Group on the Early Detection of Pancreatic Cancer has investigated and clarified the clinicopathological features for the early diagnosis of PDAC. In Japan, an algorithm for the early diagnosis of PDAC, which utilized the cooperation of local clinics and regional general hospitals, has been a breakthrough in the detection of early-stage PDAC. Further approaches for the early diagnosis of PDAC are warranted.

Backgrounds: Endoscopic ultrasonography (EUS) is used to observe the stricture of the main pancreatic duct (MPD) and in diagnosing pancreatic cancer (PC). We investigate the findings on EUS by referring to the histopathological findings of resected specimens. Materials and Methods: Six patients with carcinoma in situ (CIS) and 30 patients with invasive carcinoma of 20 mm or less were included. The preoperative EUS findings were classified as follows. A1: Simple stricture type—no findings around the stricture; A2: Hypoecho stricture type—localized hypoechoic area without demarcation around the stricture; A3: Tumor stricture type—tumor on the stricture; B: Dilation type—the dilation of the pancreatic duct without a downstream stricture; C: Parenchymal tumor type—tumor located apart from the MPD. Results: Classes A1 and A2 consisted of 2 CISs, and 4 invasive carcinomas included two cases smaller than 5 mm in diameter. Most of the cancers classified as A3 or C were of invasive carcinoma larger than 5 mm in diameter. All cancers classified as B involved CIS. Serial pancreatic-juice aspiration cytologic examination (SPACE) was selected for all types of cases, with a sensitivity of 92.0%, while EUS-guided fine needle aspiration cytology (EUS-FNA) was only useful for invasive carcinoma, and its sensitivity was 66.7%. Conclusions: Stricture without a tumor could be a finding for invasive PC and pancreatic duct dilation without a downstream stricture could be a finding indicative of CIS. Carcinoma smaller than 5 mm in diameter could not be recognized by EUS. SPACE had a high sensitivity for diagnosing small PC.

Understanding the pathogenesis and carcinogenesis of gallbladder adenocarcinoma is important. The fifth edition of the World Health Organization’s tumor classification of the digestive system indicates three types of preinvasive neoplasm of the gallbladder: pyloric gland adenoma (PGA), biliary intraepithelial neoplasia (BilIN), and intracholecystic papillary neoplasm (ICPN). New terminologies have also been introduced, such as intracholecystic papillary-tubular neoplasm, gastric pyloric, simple mucinous type, and intracholecystic tubular non-mucinous neoplasm (ICTN). Pancreatobiliary maljunction (PBM) poses a markedly high risk for bile duct carcinoma, which was analyzed and investigated mainly by Asian researchers in the past; however, recent studies have clarified a similar significance of biliary carcinogenesis in Western countries as well. In this study, we reviewed and summarized information on three gallbladder neoplastic precursors, PGA, BilIN, and ICPN, and gallbladder lesions in patients with PBM.