Synchronous Malignant Peritoneal Mesothelioma and Sigmoid Adenocarcinoma: a Challenging Clinical Entity

Our plain-English summary of Synchronous Malignant Peritoneal Mesothelioma and Sigmoid Adenocarcinoma: a Challenging Clinical Entity, by H. Alratrout, D.N. Boumarah, E.S. Alghusnah, et al (Medical Archives, 2023).

The study

• Authors: H. Alratrout, D.N. Boumarah, E.S. Alghusnah, A. Alabbad, A.H. Alsaffar, N.S. Alsafwani, M.S. Foula
• Journal: Medical Archives
• Published: 2023;77(5):400-404
• Type of article: Review, Case report
• Cited by: 2 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Background: Malignant peritoneal mesothelioma (MPM) represents a rare clinical entity. The synchronous existence of MPM with other malignancies as colonic adenocarcinoma have been rarely reported. Its diagnosis and management are challenging given its complexity and rarity.

Objective: Herein, we report a case of epithelioid subtype of MPM occurring synchronously with sigmoid colonic adenocarcinoma, along with review of the literature.

Case Presentation: An elderly female patient was referred as case of rectosigmoid mass. She reported history of abdominal pain, per-rectal bleeding, anorexia, and significant weight loss. Her computed-tomography scan of the abdomen revealed a fistulizing sigmoid mass and multiple enlarged lymphnodes with omental nodulation. The colonoscopy revealed a large fungating mass and the endoscopic biopsies were reported as colonic adenocarcinoma. The patient was scheduled laparoscopic low anterior resection. However, the diagnostic laparoscopy revealed several nodules disseminated all over the peritoneum, suggestive of peritoneal mesothelioma. Therefore, the decision was changed to create transverse colostomy after examination obtaining multiple biopsies from the omental and peritoneal nodules. The histopathological revealed MPM and the final diagnosis was sigmoid adenocarcinoma with synchronous MPM. The patient was started on palliative chemotherapy (capecitabine) without active management of MPM because of her general condition. She was followed up with a good clinical course.

Conclusion: MPM is an overlooked entity with vague clinical presentation. Synchronous MPM with colorectal cancer is rare with only few published case reports. Its diagnosis is challenging, and its management should be tailored according to the patient. This case is the first reported case in Saudi Arabia and the Middle East.

© 2023 Hefzi Alratrout, Dhuha N. Boumarah, Elham S. Alghusnah, Aqilah Alabbad, Ali H. Alsaffar, Noor S Alsafwani, Mohammed S. Foula.

In plain English

This was a case report from a Saudi Arabian university hospital, with a review of earlier published cases. A 75-year-old woman was referred with a bowel mass after abdominal pain, rectal bleeding and about 16 kilograms of weight loss. No clear history of asbestos exposure was reported. Biopsies showed adenocarcinoma of the sigmoid colon. During planned keyhole surgery, nodules were found across the peritoneum (the abdominal lining). Tests on biopsies showed epithelioid malignant peritoneal mesothelioma, not spread of the bowel cancer. She had a colostomy and reduced-dose capecitabine chemotherapy for the bowel cancer. The mesothelioma was not actively treated because of her age and general condition. She was followed for nine months with a good clinical course. The authors called this the sixth reported case worldwide of these two cancers together, and the first in Saudi Arabia and the Middle East. They noted the mesothelioma was initially overlooked partly because of the absence of asbestos exposure. They concluded that diagnosis is challenging and treatment should be tailored to the patient.

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 with a review of the literature
• Who was studied: One 75-year-old woman with hypertension, gastroesophageal reflux disease and recurrent urinary tract infections, referred to a colorectal surgery clinic at a tertiary university institute (King Fahd University Hospital, Saudi Arabia)
• Exposure: No clear history of asbestos exposure was reported by the patient. No fiber type or occupation is given.
• Main results:
  • Biopsies of the sigmoid colon mass showed moderately differentiated colonic adenocarcinoma, grade 2
  • Diagnostic laparoscopy found nodules spread over the whole peritoneum
  • Biopsies of the peritoneal nodules showed malignant mesothelioma, predominantly epithelioid subtype
  • Immunohistochemical staining (positive for pan-cytokeratin, CK7, calretinin, podoplanin/D2-40 and WT-1; negative for CK20, PAX-8 and CDX2) was consistent with mesothelial origin rather than metastatic colonic adenocarcinoma
  • The patient received a transverse colostomy and palliative reduced-dose capecitabine for the sigmoid adenocarcinoma. The peritoneal mesothelioma was not actively managed because of her age and general condition.
  • She was followed for nine months and was tolerating chemotherapy with a good clinical course
  • The mesothelioma diagnosis was initially overlooked given the absence of asbestos exposure and the confirmed colonic adenocarcinoma
  • Based on their literature review, the authors reported this as the sixth case worldwide of synchronous malignant peritoneal mesothelioma with colorectal cancer. In their table of the five earlier cases, four listed asbestos exposure as a risk factor. One listed tobacco smoking and working in construction, with no documented asbestos exposure.
• The authors' conclusion: The authors concluded that malignant peritoneal mesothelioma is an overlooked entity with vague symptoms. They said that its occurrence together with colorectal cancer is rare. They said diagnosis is challenging because radiological findings may be misinterpreted, and that management should be tailored to the patient's general condition.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Colon cancer, Mesothelioma, Peritoneal mesothelioma.

Medical terms in this study, explained in our Lexicon: Peritoneal Mesothelioma, Adenocarcinoma, Epithelioid, Diagnostic Laparoscopy, Peritoneum, Palliative Care, Chemotherapy, Capecitabine.

Related studies

• Benign multicystic mesothelioma with concurrent colonic adenocarcinoma: a report of two cases — A. Husain, M. Ozdemirli (2012)
• Whole exome sequencing of independent lung adenocarcinoma, lung squamous cell carcinoma, and malignant peritoneal mesothelioma: A case report — I. Vanni, S. Coco, et al. (2016)
• Peritoneal well-differentiated papillary mesothelioma coexisting with endometrial adenocarcinoma mimicking peritoneal carcinomatosis: A case report — Y.Y. Chen, P.C. Li, et al. (2020)
• Challenging the Norm: Occurrence of Synchronous Pleural and Peritoneal Mesothelioma in a Female Patient — S. Reddy, K. M G, et al. (2024)
• Synchronous double malignancy: adenocarcinoma of lung and malignant astrocytoma induced by asbestos exposure — T. Kishimoto, H. Hashimoto, et al. (1992)
• Comparative genetic analysis of a rare synchronous collision tumor composed of malignant pleural mesothelioma and primary pulmonary adenocarcinoma — T. Naka, Y. Hatanaka, et al. (2016)

Browse return to medical research.