Metastasis of Pleural Mesothelioma Presenting as Bleeding Colonic Polyp

We report the case of a 72-year-old woman with metastatic malignant mesothelioma presenting as right colonic polyp. She was diagnosed with malignant pleural mesothelioma 2 years previously and underwent surgery, radiotherapy, and chemotherapy. After 2 years with a negative follow-up, she was admitted to the infectious disease department for malaria and severe anaemia. A computed tomographic scan and a colonoscopy showed a huge bleeding polypoid lesion in the right colon diagnosed as adenocarcinoma. She underwent a right hemicolectomy; a pathologic examination found neoplastic cell population positive to anti-cytokeratin7, anti-calretinin, anti-vimentin, and negative for anti-cytokeratin 20, MOC-31, and thyroid transcription factor 1, providing a diagnosis of metastatic mesothelioma.