Dysplasia and carcinoma in situ of the exocrine pancreas.

Abstract

To clarify the morphological aspect of precancerous and related lesions of the exocrine pancreas, histological studies were carried out according to a systematized protocol. The pancreas, its head, body and tail including the papilla and adjacent duodenal mucosa and the distal common bile duct from 206 unselective autopsy cases, excluding those of pancreatic carcinoma, were systematically examined. Histological grading of dysplasia was performed based on structural (SAT) and cellular (CAT) atypic which were evaluated by coding 0, 1, 2, and 3. Dysplasia and related changes were encountered in 75 cases (36%) including 6 carcinoma in situ, 1 occult invasive carcinoma (3%), and 10 moderate to severe dysplasias (5%). Of these 75, 46 were associated with parenchymal fibrosis but 29 were not. Simple epithelial hyperplasia and squamous metaplasia were observed in 90 cases (44%), and 34 cases (17%), respectively. Among 90 hyperplasias, 61 were associated with fibrosis, but 29 were not. The incidence of these epithelial abnormalities was higher than that reported in the previous papers. Both dysplasia and hyperplasia showed characteristic age, sex and site preponderances. An intimate relationship between dysplasia and chronic pancreatitis, and possible transition from dysplasia into carcinoma in situ and then invasive cancer were emphasized. --carcinoma in situ; dysplasia; neoplasm; pancreas Carcinoma of the pancreas, one of the most serious human neoplasms, seems to be steadily increasing in recent years (Fitzgerald 1975). Therefore, it is well worth elucidating neoplastic and preneoplastic lesions of the pancreas from both pathological and clinical standpoints. The concept of `dysplasia' seems to represent well premalignant lesions particularly of epithelial origin, and therefore is widely acceptable (Robbins and Angell 1971;Mukada et al. 1978). In order to clarify the dysplasia and related changes of the exocrine pancreas including Vater's papilla and adjacent duodenal mucosa, and the distal common bile duct, systematized histopathological examination of autopsy materials was carried out.

A genetic roadmap of pancreatic cancer: still evolving

“…However, a recent report of extensive whole organ analysis via serial sections spaced at 5 mm identified advanced PanINs at a frequency of 4% in a hospital autopsy series47 using the current PanIN classification system. This is in agreement with data from a study from the 1980s reporting an incidence of 5% for moderate to severe dysplastic lesions 12. The accuracy of the estimates and the age-adjusted prevalence of such lesions need to be determined through additional autopsy series to control for potential selection biases.…”

Duct changes and K-ras mutations in the disease-free pancreas: analysis of type, age relation and spatial distribution

“…The early study of normal autopsy pancreases by Sommers et al [20] was the first to support this assumption. The subsequent studies by Kozuka et al [9], Klöppel et al [6] and Mukada and Yamada [16] largely confirmed Sommers' results. However, there are some inconsistencies between these studies.…”

Adenocarcinoma of the Pancreas with a Predominant Intraductal Component

“…Pure carcinoma, in situ, or minimally invasive cancers were seen in up to 7.8% of autopsy cases (26,27). Marked dysplasia, or carcinoma in situ, is seen in small papillae and flat areas as a concomitant phenomenon in invasive ductal carcinoma in up to 24% of surgical specimens (28,30).…”

“…Marked dysplasia, or carcinoma in situ, is seen in small papillae and flat areas as a concomitant phenomenon in invasive ductal carcinoma in up to 24% of surgical specimens (28,30). They show chronologically gradual transition toward distinct carcinomas (26). These dysplasias, however, were only situated in some tributaries and never were distributed throughout the pancreatic ducts.…”