A Mesothelial Inclusion Cyst Presenting in a 40-Year-Old Woman as Abdominal Pain and Bloating - A Rare Diagnosis

Our plain-English summary of A Mesothelial Inclusion Cyst Presenting in a 40-Year-Old Woman as Abdominal Pain and Bloating - A Rare Diagnosis, by S. Canadas, R. Fernandes, H. Almeida, et al (European Journal of Case Reports in Internal Medicine, 2020).

The study

• Authors: S. Canadas, R. Fernandes, H. Almeida, J.S. Correia
• Journal: European Journal of Case Reports in Internal Medicine
• Published: 2020;7(2):001415
• Cited by: 1 article, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Unlabelled: Cystic mesotheliomas (also called mesothelial inclusion cysts) are rare benign neoplasms that occur more often in young women. Symptoms are usually non-specific, demanding a thorough work-up. We report a case of a 40-year-old female patient with 2 prior caesarean sections presenting with a 3-month history of abdominal pain. Laboratory tests revealed microcytic hypochromic anaemia and an elevated tumour marker CA-125. An investigation identified a large cystic abdominal mass, mostly in the left side of the abdomen. A laparotomy was performed with total resection of the lesion. Histological assessment resulted in a diagnosis of a mesothelial inclusion cyst. The patient had no recurrence after 3 years.

Learning Points: Peritoneal mesotheliomas are rare conditions, and with benign features are even rarer.Mesothelial inclusion cysts, also known as benign cystic mesothelioma, occur more often in young to middle-aged women with excellent prognosis, although there are high rates of local recurrence.Investigation unmasks large abdominal lesions. A timely diagnosis is of the utmost importance, to prevent a dramatic change in outcome if severe complications develop.

© EFIM 2020.

In plain English

This article is a case report of one patient, written by doctors at Hospital Sousa Martins in Guarda, Portugal. A 40-year-old woman who had previously had two caesarean deliveries had diffuse abdominal pain and bloating over the previous 3 months. Blood tests showed microcytic hypochromic anaemia (anaemia with small, pale red blood cells) and a raised level of the tumour marker CA-125. Because the doctors first suspected cancer, she had a CT scan and then an MRI. The MRI showed a 16 cm cystic mass in the abdomen. Surgeons removed the whole lesion in an open abdominal operation (laparotomy). Under the microscope it was classified as a peritoneal mesothelial inclusion cyst, also called benign cystic mesothelioma. After 3 years of close follow-up there was no evidence that it had come back. The article does not describe any asbestos exposure for this patient. In their discussion, citing earlier publications, the authors wrote that this benign condition has no association with asbestos exposure, unlike malignant peritoneal mesothelioma. The authors concluded that the condition has a good prognosis but is difficult to diagnose correctly before surgery.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case report (one patient)
• Who was studied: One 40-year-old Caucasian woman with grade 1 obesity, hypothyroidism, idiopathic hyperprolactinaemia and two prior caesarean deliveries. She presented with diffuse abdominal pain and bloating over the previous 3 months. The authors are from Hospital Sousa Martins, Guarda, Portugal. Dates of care are not given.
• Exposure: The article reports no asbestos or other exposure history for this patient. The authors suggested the cyst may be related to her history of abdominal surgeries (two caesarean sections).
• Main results:
  • The patient had diffuse abdominal pain and abdominal bloating over 3 months.
  • Blood tests in the patient showed microcytic hypochromic anaemia and an elevated tumour marker CA-125.
  • Because a malignant disease was initially suspected, a CT scan was done.
  • MRI confirmed a 16 cm cystic mass in the patient's abdomen.
  • The lesion was completely removed by laparotomy.
  • On histology, the lesion was classified as a peritoneal mesothelial inclusion cyst (benign cystic mesothelioma).
  • After 3 years of close follow-up there was no evidence of recurrence in this patient.
  • In the discussion, citing earlier publications (references 1 and 4) rather than this case, the authors stated that benign cystic mesothelioma has no association with asbestos exposure, in contrast to malignant peritoneal mesothelioma.
• The authors' conclusion: The authors concluded that this condition has a good prognosis, but that correct diagnosis before surgery is difficult.

Topics

Medical terms in this study, explained in our Lexicon: Mesothelioma, Neoplasm, CA-125, Laparotomy, Peritoneal Mesothelioma, Prognosis.

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