| Theme |
Small colorectal cancer with high malignant potential |
| Title |
Clinicopathological features and treatment strategies for submucosal invasive colorectal cancers |
| Author |
Takahisa Matsuda |
Endoscopy Division, National Cancer Center Hospital |
| Author |
Taku Sakamoto |
Endoscopy Division, National Cancer Center Hospital |
| Author |
Takeshi Nakajima |
Endoscopy Division, National Cancer Center Hospital |
| Author |
Eriko So |
Endoscopy Division, National Cancer Center Hospital |
| Author |
Masayoshi Yamada |
Endoscopy Division, National Cancer Center Hospital |
| Author |
Hirokazu Taniguchi |
Pathology Division, National Cancer Center Hospital |
| Author |
Ryoji Kushima |
Pathology Division, National Cancer Center Hospital |
| Author |
Takahiro Fujii |
TF Clinic |
| Author |
Yutaka Saito |
Endoscopy Division, National Cancer Center Hospital |
| [ Summary ] |
Early invasive colorectal cancers (EI-CRCs) can be detected even when quite small. However, the grade of malignancy for these small submucosal invasive cancers has not been fully investigated. To clarify the clinicopathological characteristics of EI-CRCs we divided the subjects into two groups, those with smaller or larger lesions. This was done to confirm whether the grade of malignancy depends on size. A total of 1,217 EI-CRC patients treated with EMR or surgery at the NCCH between 1980 and 2011 were enrolled in this study. Lesions were classified into the following two groups based on size for detailed analysis: small (<- 10 mm) and large (> 10 mm). Clinicopathological features, incidence of lymph node metastasis (LNM) and risk factors for LNM such as invasion depth and lymphovascular invasion (LVI) were analyzed in all resected specimens. There were 239 (20 %) and 978 (80 %), small and large lesions respectively. Histopathological analysis of the group with small lesions revealed submucosal (SM) deep cancer (SM: >- 1,000µm) in 172 (72 %) cases and LVI in 59 (25 %) cases. Similarly, the large group exhibited SM deep cancer in 736 (75 %) cases, LVI in 246 (25 %) cases, respectively. Moreover, the rate of LNM was 13.3 % and 11.6 % in small and large groups, respectively. Small EI-CRCs demonstrated the same aggressiveness and malignancy potential as large lesions. Special attention must be paid when treating even small lesions. |