| Theme |
New Development of Laterally Spreading Tumor |
| Title |
Frequency and Yearly Transition of LST |
| Author |
Shin‒ei Kudo |
Digestive Disease Center, Showa University Northern Yokohama Hospital |
| Author |
Tomoyuki Ishigaki |
Digestive Disease Center, Showa University Northern Yokohama Hospital |
| Author |
Takemasa Hayashi |
Digestive Disease Center, Showa University Northern Yokohama Hospital |
| Author |
Toyoki Kudo |
Digestive Disease Center, Showa University Northern Yokohama Hospital |
| Author |
Hideyuki Miyachi |
Digestive Disease Center, Showa University Northern Yokohama Hospital |
| Author |
Fumio Ishida |
Digestive Disease Center, Showa University Northern Yokohama Hospital |
| [ Summary ] |
Laterally spreading tumors (LSTs) are classified into four subtypes. These subgroups differ from each other in clinicopathological features and in frequency. We performed a retrospective analysis focusing on the frequency of LSTs by comparing all colorectal neoplasms and LSTs, from low grade adenoma to pT1 cancer, that were resected at our institution. Our results indicate that the frequency of LSTs was 10.5 % increased yearly. The frequency of LSTs and the submucosa (SM) invasive rate increased with age. The frequency of LSTs was significantly higher in women, and that rate increased in the rectum and right colon during recent years. The most frequent sub‒type of LSTs observed was the non‒granular flat elevated type. |