Mucinous tumors arising from ovarian teratomas as another source of pseudomyxoma peritoneii: MR findings comparison with ovarian metastases from appendiceal mucinous tumors

Yumiko Oishi Tanaka; Emiko Sugawara; Akiko Tonooka; Tsukasa Saida; Akiko Sakata; Yosuke Fukunaga; Hiroyuki Kanao; Toyomi Satoh; Masayuki Noguchi; Takashi Terauchi

doi:10.1259/bjro.20220036

Mucinous tumors arising from ovarian teratomas as another source of pseudomyxoma peritoneii: MR findings comparison with ovarian metastases from appendiceal mucinous tumors

BJR Open. 2023 Apr 19;5(1):20220036. doi: 10.1259/bjro.20220036. eCollection 2023.

Authors

Yumiko Oishi Tanaka, Emiko Sugawara¹, Akiko Tonooka², Tsukasa Saida³, Akiko Sakata⁴, Yosuke Fukunaga⁵, Hiroyuki Kanao⁶, Toyomi Satoh⁷, Masayuki Noguchi⁸, Takashi Terauchi⁹

Affiliations

¹ Department of Pathology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
² Division of Pathology, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan.
³ Department of Diagnostic & Interventional Radiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
⁴ Department of Diagnostic Pathology, Tsukuba University Hospital, Tsukuba, Japan.
⁵ Colorectal Surgery Department, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
⁶ Department of Gynecologic Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.
⁷ Department of Obstetrics & Gynecology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
⁸ Department of Diagnostic Pathology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
⁹ Diagnostic Imaging Department, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan.

Abstract

Objective: The origin of pseudomyxoma peritoneii (PMP) has been established as low-grade appendiceal mucinous tumors (AMT). However, intestinal-type ovarian mucinous tumors are known as another source of PMP. Recently, it is advocated that ovarian mucinous tumors causing PMP originates from teratomas. However, AMTs are often too small to detect on imaging; then, differentiating metastatic ovarian tumors of AMT from ovarian teratoma-associated mucinous tumors (OTAMT) is important. Therefore, this study investigates the MR characteristics of OTAMT compared to the ovarian metastasis of AMT.

Methods: MR findings of six pathologically confirmed OTAMT were retrospectively analyzed compared to ovarian metastases of low-grade appendiceal mucinous neoplasms (LAMN). We studied the existence of PMP, uni- or bilateral disease, the maximum diameter of ovarian masses, the number of loculi, a variety of sizes and signal intensity of each content, the existence of the solid part, fat, calcification within the mass, and appendiceal diameters. All the findings were statistically analyzed using the Mann-Whitney test.

Results: Four of the six OTAMT showed PMP. OTAMT showed unilateral disease, had a larger diameter, more frequent intratumoral fat, smaller appendiceal diameter than those in AMT, and they were statistically significant (p < .05). On the other hand, the number, variety of size, signal intensity of loculi, and the solid part, calcification within the mass did not differ from each other.

Conclusion: Both OTAMT and ovarian metastasis of AMT appeared as multilocular cystic masses with relatively uniform signal and size of loculi. However, a larger unilateral disease with intratumoral fat and smaller size of the appendix may suggest OTAMT.

Advances in knowledge: OTAMT can be another source of PMP, as AMT. MR characteristics of OTAMT were very similar to ovarian metastases of AMT; however, in cases with PMP combined with fat-containing multilocular cystic ovarian mass, we can diagnose them as OTAMT, not PMP caused by AMT.