Tohoku J. Exp. Med., 2020 September, 252 (1)

Focal Parenchymal Atrophy and Fat Replacement Are Clues for Early Diagnosis of Pancreatic Cancer with Abnormalities of the Main Pancreatic Duct

SHIN MIURA,¹ KIYOSHI KUME,¹ KAZUHIRO KIKUTA,¹ SHIN HAMADA,¹ TETSUYA TAKIKAWA,¹ NAOKI YOSHIDA,¹ SEIJI HONGO,¹ YU TANAKA,¹ RYOTARO MATSUMOTO,¹ TAKANORI SANO,¹ MIO IKEDA,¹ TORU FURUKAWA,² MASAHIRO ISEKI,³ MICHIAKI UNNO³ and ATSUSHI MASAMUNE¹

¹Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
²Department of Investigative Pathology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
³Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan

Pancreatic cancer is one of the most dangerous solid tumors, but its early diagnosis is difficult. The abnormality of the main pancreatic duct (MPD), such as a single localized stricture and upstream dilatation, might be useful in the early detection of pancreatic cancer. However, these findings are often observed in benign inflammatory cases. This study aimed to clarify whether early pancreatic cancer presenting MPD abnormalities has characteristic features different from those of benign cases. This is a single-center, retrospective study. We analyzed 20 patients who underwent pancreatectomy presenting with a single, localized MPD stricture without identifiable masses on imaging: 10 patients with pancreatic ductal adenocarcinoma (cancer group; 6 with stage 0 and 4 with stage I) and 10 patients with benign strictures (benign group; 8 with inflammation and 2 with low-grade pancreatic intraepithelial neoplasms). Pancreatectomy was performed in these benign cases because high-grade intraepithelial neoplasm was suspected. Although the proportion of patients with diabetes mellitus tended to be higher in the cancer group (6/10) than that in the benign group (1/10) (P = 0.058), other clinical characteristics were not different between the groups. Preoperative cytological malignancies were detected in four patients in the cancer group (4/10) but not in the benign group (P = 0.09). Focal parenchymal atrophy and fat replacement were more frequently detected on computed tomography in the cancer group (7/10) than in the benign group (1/10) (P = 0.02). In conclusion, focal parenchymal atrophy and fat replacement may provide clues for the early diagnosis of pancreatic cancer.

Keywords —— early pancreatic cancer; endoscopic ultrasound; pancreatic intraepithelial neoplasia; pancreatitis; serial pancreatic juice aspiration cytological examination

© 2020 Tohoku University Medical Press

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Tohoku J. Exp. Med., 2020 , 252, 63-71.

Correspondence: Atsushi Masamune, M.D., Ph.D., Division of Gastroenterology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan.

e-mail: amasamune@med.tohoku.ac.jp