From the *Department of Gastroenterology, Sendai City Medical Center, Sendai; †Center for Gastroenterology, Teine-Keijinkai Hospital, Sapporo; ‡Department of General Medicine, Asahikawa Medical College, Asahikawa; §Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya; ∥Center for Gastroendoscopy, Onomichi General Hospital, Hiroshima; ¶Department of Surgery, Institute of Gastroenterology, Tokyo Women's Medical University, Tokyo; #Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka; **Department of Gastroenterology, Chiba Cancer Center, Chiba; ††Department of Gastroenterological Surgery, Tokai University School of Medicine, Kanagawa; ‡‡Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Kyoto University; and §§Department of Pathology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Pancreas. 2014 May;43(4):532-8. doi: 10.1097/MPA.0000000000000080.
This study aimed to elucidate the natural history of intraductal papillary mucinous neoplasm (IPMN) of the pancreas with mural nodules (MNs) in branch duct IPMN (BD-IPMN).
Among the 402 registered patients with BD-IPMN on long-term follow-up at 10 institutions in Japan, 53 patients with MNs of less than 10 mm in height detected by endosonography were included in this study. The morphological changes of the BD-IPMN in these patients and histologic findings of the resected specimen were investigated.
The median height of the MNs at the initial diagnosis was 3 mm (range, 1-8 mm), and 12 (23%) of the 53 patients showed an increase in the height of the MNs during follow-up (mean duration, 42 months). Six patients underwent surgery because of an increase in the height of MNs, yielding high-grade dysplasia in 1 patient and low-grade dysplasia in 5 patients. No patients developed invasive carcinoma derived from IPMN, and distinct pancreatic ductal adenocarcinoma developed in 1 (2%) patient. The incidence of the development of malignancy in BD-IPMNs, including distinct pancreatic ductal adenocarcinoma, was similar to that of those without MNs.
In patients who have BD-IPMN with MNs of less than 10 mm in height, observation instead of immediate resection is considered to be possible.
本研究旨在阐明胰腺分支胰管内乳头状黏液性肿瘤（BD-IPMN）伴壁内结节（MNs）的自然病史。
在日本 10 家机构对 402 例长期随访的 BD-IPMN 患者进行登记，其中 53 例患者经超声内镜检查发现高度小于 10mm 的 MNs，纳入本研究。对这些患者的 BD-IPMN 的形态变化和切除标本的组织学发现进行了研究。
MNs 最初诊断时的中位高度为 3mm（范围 1-8mm），53 例患者中有 12 例（23%）在随访期间 MNs 高度增加（平均持续时间为 42 个月）。6 例患者因 MNs 高度增加而行手术治疗，其中 1 例为高级别异型增生，5 例为低级别异型增生。无患者发生源自 IPMN 的浸润性癌，且 1 例（2%）患者发生明显胰腺导管腺癌。包括明显胰腺导管腺癌在内的 BD-IPMN 发生恶性肿瘤的发生率与无 MNs 的患者相似。
对于高度小于 10mm 的 MNs 的 BD-IPMN 患者，考虑观察而非立即切除可能是可行的。
