title: Signet-ring cell carcinoma of the appendix: a case report with an emphasis on sonographic findings.
abstract: In this report, we present a rare case of primary signet-ring cell carcinoma of the appendix in a 51-year-old woman with right lower quadrant pain. Since non-specific concentric appendiceal wall thickening was found in a radiologic evaluation, it was misdiagnosed as non-tumorous appendicitis. An in-depth examination of the correlation between sonographic and histopathologic findings demonstrated that a single markedly thickened hypoechoic layer was well correlated with the diffuse infiltration of tumor cells in both the submucosal and muscle layers. If this sonographic finding is observed in certain clinical settings, such as potential ovarian and peritoneal metastasis, submucosal infiltrative tumors, including signet-ring cell carcinoma, should be considered in the differential diagnosis.
authors.affiliation: Department of Radiology, Daejin Medical Center, Bundang Jesaeng General Hospital, Seongnam, Korea.
authors.forename: Young Jong
authors.identifier: 0000-0003-2881-9221
authors.initials: YJ
authors.lastname: Cho
authors.affiliation: Department of Radiology, Daejin Medical Center, Bundang Jesaeng General Hospital, Seongnam, Korea.
authors.forename: Hyuk Jung
authors.identifier: 0000-0002-4629-4142
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Radiology, Daejin Medical Center, Bundang Jesaeng General Hospital, Seongnam, Korea.
authors.forename: Suk Ki
authors.identifier: 0000-0002-8625-7573
authors.initials: SK
authors.lastname: Jang
authors.affiliation: Department of Radiology, Daejin Medical Center, Bundang Jesaeng General Hospital, Seongnam, Korea.
authors.forename: Jae Woo
authors.identifier: 0000-0002-1612-6279
authors.initials: JW
authors.lastname: Yeon
authors.affiliation: Department of Surgery, Daejin Medical Center, Bundang Jesaeng General Hospital, Seongnam, Korea.
authors.forename: Ki-Ho
authors.identifier: 0000-0003-0100-7936
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Department of Diagnostic Pathology, Daejin Medical Center, Bundang Jesaeng General Hospital, Seongnam, Korea.
authors.forename: So Ya
authors.identifier: 0000-0003-4707-574X
authors.initials: SY
authors.lastname: Paik
keywords: Appendix; Carcinoma, signet ring cell; Ultrasonography