Histopathological discrepancy and variation of surgical management in mucinous ovarian cystadenoma and pseudomyxoma peritonei

Abstract

Introduction and importance: Mucinous cystadenoma occurs in 10-15% of all ovarian tumors. Diagnosis and treatment should be decided precisely as it has a chance to develop into pseudomyxoma peritonei (PMP). Management of PMP might be challenging especially when repeated surgery is needed.

Case presentation: The first case, a 22-year-old lady with recurrent stomach enlargement for seven months. She had history of laparotomy surgery due to an ovarian tumor. Whole abdomen contrast CT scan showed a large cyst with mucinous fluid. We decided to do re-laparotomy and found a left ovarian cyst. Histological examination results confirm ovarian mucinous cystadenoma. The second case was, 55-year-old woman, with abdominal enlargement for six months. She had a history of laparotomy and chemotherapy due to pseudomyxoma peritonei. Post chemotherapy MRI showed persistent pseudomyxoma and two multilocular cysts from both adnexa. Debulking laparotomy was then conducted. We obtained 8 L of mucinous pseudomyxoma along with mucinous cyst from both ovaries. The final diagnosis concluded as a pseudomyxoma and we decide to close the follow-up of the patient.

Clinical discussion: Pseudomyxoma is caused by the production of mucin originating from intra-abdominal organs. Open surgery should be prioritized when the mucinous cystadenoma is detected to do a complete peritoneum evaluation and avoid perioperatively ruptured mucinous neoplasm. Pseudomyxoma often needed repeated surgical treatment and may exhibit different surgical findings and different pathologies.

Conclusion: Repeated surgery is logical and still no need for adjuvant chemotherapy in both cases. Accurate and precise diagnosis should be prioritized in order to prevent repeated surgery.

Keywords: Cytoreductive surgery; Mucinous cystadenoma; Pseudomyxoma peritonei.

Fig. 1

CT whole abdomen with contrast showed a large cystic multilocular septated lesion with mucinous fluid.

Fig. 2

(a–e). Ovarian cystadenoma originating from left ovary with 40 cm diameter.

Fig. 3

CT-Scan whole abdomen: A. Pre surgery (July 2020) showing ascites in the abdominopelvic cavity, B. post surgery (October 2020) showing fluid accumulation and multilocular cystic mass in the abdominopelvic cavity.

Fig. 4

MRI whole abdomen showed accumulated fluid filling the entire intraperitoneal cavity and two multilocular cysts after six courses of chemotherapy.

Fig. 5

A. Enlarged abdomen with fluid accumulation and adnexal mass. B. Eight liters of jelly fluid. C. Macroscopic surgical specimens after surgery.

Fig. 6

Immunohistochemistry labeling results (obj ×100). A. Mucinous cystadenoma with borderline focus HE staining. B. Positive control: +3 score HER2. C. Negative control HER2. D. +2 result HER2: equifocal weak-to-moderate complete membrane staining. E. Immunopathology CISH ratio HER2/CEP17: 2.27 and an average HER2 signals/cell: 5.45 (HER2 positive). F. Pseudomyxoma Hematoxylin-Eosin (HE) staining. G. Positive control: +3 score HER2. H. Negative control HER2. I. Negative result of HER2. J. Immunopathology CISH Ratio HER2/Cen17: 1.3 (negative).