title: Cytoreductive Surgery Plus Hyperthermic Intraperitoneal Chemotherapy for Pseudomyxoma Peritonei Arising from Urachus.
abstract: BACKGROUND
  Pseudomyxoma peritonei (PMP) is a rare locoregional disease characterized by disseminated intraperitoneal mucinous tumors. However, little is known about PMP from urachal neoplasm as a result of its rarity.
  
  
  METHODS
  A total of 9 patients with PMP of urachal origin were treated by cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in our institution. All specimens of surgeries were submitted for pathologic examination. Representative slides of tumors and normal urachus were submitted for immunohistochemical staining.
  
  
  RESULTS
  Four patients were men; the median age was 48 years (range 27-65 years). Initial radiologic examination of all patients showed a cystic tumor located between posterior aspect of umbilicus and the dome of urinary bladder, with or without leaking mucin. Complete CRS and HIPEC were performed in all patients. Until the latest follow-up, local recurrence occurred in 1 patient. Other 8 patients had a median disease-free survival of 27.5 months. Primary urachal tumors of 9 cases were all mucinous adenocarcinoma. Six patients had low-grade mucinous carcinoma peritonei, and 3 patients had high-grade mucinous carcinoma peritonei. Signet ring cells were noted in 4 patients. All tumor specimens of 9 patients were diffuse positive for CK-20, CDX-2, MUC-2, and MUC-5AC, and were variant positive for CK-7.
  
  
  CONCLUSIONS
  PMP arising from urachus comes from neoplastic cells with development of intestinal-type mucinous neoplasm. It shares a similar pathophysiology as PMP from appendix. CRS including total urethrectomy, partial cystectomy, and peritonectomy plus HIPEC can be considered as a new option of treatment for PMP originating from urachus.
authors.affiliation: NPO to Support Peritoneal Surface Malignancy Treatment, Osaka, Japan.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Haruaki
authors.initials: H
authors.lastname: Ishibashi
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Hirano
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Takeshita
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Mizumoto
authors.forename: Masumi
authors.initials: M
authors.lastname: Ichinose
authors.forename: Eisei
authors.initials: E
authors.lastname: Nishino
authors.forename: Ippei
authors.initials: I
authors.lastname: Kashu
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Paul H
authors.initials: PH
authors.lastname: Sugarbaker
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yonemura
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000737:chemistry / Q000473:pathology / Q000628:therapy*; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D000071616:CDX2 Transcription Factor; D002945:Cisplatin / Q000008:administration & dosage; D065426:Cytoreduction Surgical Procedures; D018572:Disease-Free Survival; D005260:Female; D018398:Homeodomain Proteins / Q000032:analysis; D006801:Humans; D006979:Hyperthermia, Induced; D007263:Infusions, Parenteral; D053554:Keratin-20 / Q000032:analysis; D053552:Keratin-7 / Q000032:analysis; D008297:Male; D008875:Middle Aged; D016685:Mitomycin / Q000008:administration & dosage; D055271:Mucin 5AC / Q000032:analysis; D055262:Mucin-2 / Q000032:analysis; D010534:Peritoneal Neoplasms / Q000737:chemistry / Q000473:pathology / Q000628:therapy*; D011553:Pseudomyxoma Peritonei / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D015534:Trans-Activators / Q000032:analysis; D014497:Urachus
chemical_list: D000071616:CDX2 Transcription Factor; D018398:Homeodomain Proteins; D053554:Keratin-20; D053552:Keratin-7; C524625:MUC2 protein, human; C524678:MUC5AC protein, human; D055271:Mucin 5AC; D055262:Mucin-2; D015534:Trans-Activators; D016685:Mitomycin; D002945:Cisplatin