A case of Pseudomyxoma Peritonei of an unexpected origin

Abstract

Background Pseudomyxoma peritonei (PMP) is a complex and partially understood disease defined by mucin deposits in the peritoneal cavity, mostly of appendiceal origin caused by the rupture of a mucocele often containing Low or High grade Appendiceal Mucinous Neoplasm (LAMN/HAMN). Other origins include primitive ovarian mucinous cystadenoma or cystadenocarcinoma almost always with an associated teratoma, but to our knowledge no case of ovarian teratomatous appendiceal-like mucocele with LAMN has been reported as a cause of PMP. Case presentation A 25-year old female with infertility was diagnosed with an isolated left ovarian tumor in a context of PMP. Histological examination revealed an ovarian teratoma containing an appendiceal-like structure with mucocele and LAMN, without any associated lesion of the appendix on full histological analysis. Molecular characterization of the ovarian lesion showed co-KRAS and GNAS mutations, as described in PMP of appendiceal origin, while only KRAS mutations are reported in primitive ovarian mucinous tumor. Conclusions Detection of co-KRAS and GNAS mutations in our case of ovarian teratomatous appendiceal-like mucocele with LAMN shows that when PMP derives from a mucinous ovarian lesion (with histological proof of none-appendiceal involvement), it is probably of a digestive teratomatous origin, emphasizing the need to actively search for tetatomatous signs in a context of ovarian PMP.

Pseudomyxoma peritonei induced by a well‐differentiated appendicular mucinous adenocarcinoma: An uncommon cause of isolated ascites in a young man patient

“…Most tumors (90%) are of appendicular origin from low‐ or high‐grade mucinous appendicular neoplasm and appendicular adenocarcinoma, associated with a mucocele, as in our patient's case 1–7 . Other tumors are mucinous adenocarcinomas of colonic, gastric, pancreatic, urachal, pulmonary, endocervical or mammary origin, or more rarely mucinous ovarian tumors, cystadenomas, or cystadenocarcinomas 2,8 . Some authors have reported non‐neoplastic intraperitoneal mucinous deposits caused by alternative processes such as mucin retention due to a stercolith or diverticulum, or mucinous metaplasia of the fallopian tubes, but such situations are very rare and debatable 2,9 …”

“…[1][2][3][4][5][6][7] Other tumors are mucinous adenocarcinomas of colonic, gastric, pancreatic, urachal, pulmonary, endocervical or mammary origin, or more rarely mucinous ovarian tumors, cystadenomas, or cystadenocarcinomas. 2,8 Some authors have reported non-neoplastic intraperitoneal mucinous deposits caused by alternative processes such as mucin retention due to a stercolith or diverticulum, or mucinous metaplasia of the fallopian tubes, but such situations are very rare and debatable. 2,9 Its pathophysiology is explained by the obstruction of the appendicular lumen due to a hypersecretion of mucus by the appendix leading to its progressive distension, called appendicular mucocele.…”

Pseudomyxoma Peritonei: A Challenging Clinical Diagnosis. Case Report and Review of the Literature

“…Cytoreductive surgery, with or without hyperthermic intraperitoneal chemotherapy (HIPEC), despite possible concomitant morbidity is considered the proper treatment (42). Although several approaches have been described so far, the radical removal of all intra-abdominal and pelvic disease and the administration of intraperitoneal heated chemotherapy (mitomycin, 5-FU) have been adopted by most clinicians (43,44).…”

Pseudomyxoma peritonei induced by a well-differentiated appendicular mucinous adenocarcinoma: An uncommon cause of isolated ascites in a young man patient

“…[1][2][3][4][5][6][7] Other tumors are mucinous adenocarcinomas of colonic, gastric, pancreatic, urachal, pulmonary, endocervical or mammary origin, or more rarely mucinous ovarian tumors, cystadenomas or cystadenocarcinomas. 2,8 Some authors have reported nonneoplastic intraperitoneal mucinous deposits caused by alternative processes such as mucin retention due to a stercolith or diverticulum, or mucinous metaplasia of the fallopian tubes, but such situations are very rare and debatable. 2,9 Its pathophysiology is explained by the obstruction of the appendicular lumen due to a hypersecretion of mucus by the appendix leading to its progressive distension, called appendicular mucocele.…”