Pathological Features and Imaging Findings in Pancreatic Carcinoma In Situ
Keiji Hanada, Motomitsu Fukuhara, Tomoyuki Minami, Shigeki Yano, Juri Ikemoto, Akinori Shimizu, Keisuke Kurihara, Yasuhiro Okuda, Morito Ikeda, Masataka Yokode, Tomoyuki Abe, Shuji Yonehara, Akio Yanagisawa
Abstract
OBJECTIVES: This study aimed to evaluate the pathological features and imaging findings of pancreatic carcinoma in situ (PCIS). METHODS: Twenty patients with PCIS were categorized as flat (F) (n = 6) and low papillary (LP) (n = 14) types. RESULTS: None of F type and 8 (57%) of 14 with LP type lesions showed intraductal infiltrations of the main pancreatic duct (MPD) greater than 10 mm. None of F type and 3 (21%) of 14 with LP type lesions showed skip lesions in the MPD. Magnetic resonance cholangiopancreatography showed irregular MPD stenoses in 5 (83%) of 6 with F and 13 (100%) of 13 with LP type lesions. Magnetic resonance cholangiopancreatography determined that the median lengths of the irregular MPD stenoses were 3.6 mm for F, and 11.6 mm for LP type lesions. Endoscopic retrograde cholangiopancreatography determined that the median lengths of the irregular MPD stenoses were 2.8 mm for F, and 14.3 mm for LP type lesions. Pancreatic cancer recurrences limited to the remnant pancreas occurred in 2 patients with LP type lesions. CONCLUSIONS: In LP type PCIS, intraductal infiltration of the MPD occurs frequently. There may be multiple lesions, and lesions may recur in the remnant pancreas. Long-term strict follow-up assessments should be implemented for LP type PCIS.