| Theme | Molecular biology of colorectal tumors | |
|---|---|---|
| Title | Case of colonic cancer of MSS phenotype occurring in sessile serrated adenoma/polyp | |
| Publish Date | 2018/09 | |
| Author | Keisuke Kawasaki | Division of Gastroenterology, Department of Internal Medicine, Iwate Medical University, |
| Author | Makoto Eizuka | Department of Diagnostic Pathology, Iwate Medical University |
| Author | Shunichi Yanai | Division of Gastroenterology, Department of Internal Medicine, Iwate Medical University |
| Author | Kazuyuki Ishida | Department of Diagnostic Pathology, Iwate Medical University |
| Author | Masaki Endo | Division of Gastroenterology, Department of Internal Medicine, Iwate Medical University / Kaiunbashi Endoscopy Clinic |
| Author | Shotaro Nakamura | Division of Gastroenterology, Department of Internal Medicine, Iwate Medical University |
| Author | Tamotsu Sugai | Department of Diagnostic Pathology, Iwate Medical University |
| Author | Takayuki Matsumoto | Division of Gastroenterology, Department of Internal Medicine, Iwate Medical University |
| [ Summary ] | A 43-year-old woman underwent a colonoscopy because of positive fecal occult blood findings. Colonoscopy revealed a sessile polypoid lesion with a central depression. Magnifying colonoscopic findings suggested a diagnosis of cancer in a sessile serrated adenoma/polyp (SSA/P). The patient was subsequently treated with endoscopic mucosal resection. Histological examinations exhibited moderately to well differentiated adenocarcinoma in the SSA/P with deep submucosal invasion. Molecular findings revealed that both SSA/P and cancer were positive for BRAF mutations and a high methylation epigenotype. However, an analysis of microsatellite stability revealed that both SSA/P and cancer were microsatellite stable. The patient was diagnosed as having colonic cancer with a MSS phenotype occurring with SSA/P. | |