Malignant peritoneal mesothelioma: clinicopathological characteristics of two cases

Peritoneal mesothelioma causing small bowel obstruction in COVID-19 positive patient

Mesothelioma is a disease process that can present in a variety of locations including the pleural, peritoneum and pericardium. Malignant peritoneal mesothelioma has been known to be a particularly aggressive type of tumor. We report a case of a patient who presented with a small bowel obstruction whose pathology revealed peritoneal malignant mesothelioma.

Primary malignant peritoneal mesothelioma mimicking tuberculous peritonitis: A case report

BACKGROUND

Malignant peritoneal mesothelioma (MPM) is a rare malignancy arising in mesothelial cells in the peritoneum. It can be mistaken for many other diseases, such as peritoneal carcinomatosis and tuberculous peritonitis (TBP), because its clinical manifestations are often nonspecific. Therefore, the diagnosis of MPM is often challenging and delayed.

CASE SUMMARY

A 42-year-old man was referred to our hospital with lower abdominal pain for 1 wk and ascites observed under abdominal sonography. His laboratory findings revealed an isolated elevated tumor marker of carcinoma antigen 125 (167.4 U/mL; normal, < 35 U/mL), and contrast enhanced computed tomography showed peritoneal thickening. Thus, differential diagnoses of TBP, carcinomatosis of an unknown nature, and primary peritoneal malignancy were considered. After both esophagogastroduodenoscopy and colonoscopy produced negative findings, laparoscopic intervention was performed. The histopathological results revealed mesothelioma invasion into soft tissue composed of a papillary, tubular, single-cell arrangement of epithelioid cells. In addition, immunohistochemical staining was positive for mesothelioma markers and negative for adenocarcinoma markers. Based on the above findings, TBP was excluded, and the patient was diagnosed with MPM.

CONCLUSION

It is important to distinguish MPM from TBP because they have similar symptoms and blood test findings.

Malignant Peritoneal Mesothelioma: A Rare Cause of Ascites

Malignant peritoneal mesothelioma (MPM) is a rare diagnosis that presents with difficulties in diagnosis and management. This article reports a case of an 88-year-old male who presented with a 2-week history of abdominal distention and bloating. He worked at an insulation production factory between the ages of 23 and 25 years with presumed asbestos exposure. On the computed tomography scan of the abdomen/pelvis, the patient was found to have diffuse omental, peritoneal, and mesenteric nodularity with moderate to large ascites. Omental biopsy revealed MPM. The overall prognosis of MPM remains poor, with a median survival time of 12 months at the time of diagnosis. Treatment modalities offered in the United States include chemotherapy alone, cytoreductive surgery alone, or cytoreductive surgery/chemotherapy combination.

Primary Peritoneal Mesothelioma Resulting in Small Bowel Obstruction: A Case Report and Review of Literature

BACKGROUND

Peritoneal mesothelioma is a rare malignancy that affects the serosal surfaces of the peritoneum. The peritoneum is the second most common site of mesothelium affected following the pleura. The aggressive nature and vague presentation pose many obstacles in not only diagnosis but also the treatment of patients with this disease.

CASE REPORT

We present a case of a 76-year-old woman who presented with small bowel obstruction secondary to carcinomatosis secondary to primary peritoneal mesothelioma. The patient had multiple risk factors with asbestos exposure and prior therapeutic radiation.

CONCLUSIONS

We discuss the highly varied and elusive presentation of peritoneal mesothelioma. Cumulative asbestos exposure, either directly or indirectly, remains the leading cause of mesothelioma. However, there are other non-asbestos etiologies. Small bowel obstruction often is a late-presenting symptom of widespread tumor burden. A concise review of the current diagnostic and surgical treatment of primary peritoneal mesothelioma demonstrates that early diagnosis and implementation remains vital.