Eiji Shinto1, Keiichi Takahashi2, Tatsuro Yamaguchi2, Yojiro Hashiguchi3, Kenjiro Kotake4, Michio Itabashi5, Masamichi Yasuno6, Yukihide Kanemitsu7, Genichi Nishimura8, Yoshito Akagi9, Toshihiko Sato10, Tomoyuki Kato11, Hiroshi Matsumoto2, Kazuo Hase12, Kenichi Sugihara13. 1. Department of Surgery, National Defense Medical College, Tokorozawa, Saitama, Japan. eiji-c@zf6.so-net.ne.jp. 2. Department of Surgery, Tokyo Metropolitan Cancer and Infectious Diseases Center, Komagome Hospital, Tokyo, Japan. 3. Department of Surgery, Teikyo University, Tokyo, Japan. 4. Department of Surgery, Tochigi Cancer Center, Utsunomiya, Japan. 5. Department of Surgery II, Tokyo Women's Medical University, Tokyo, Japan. 6. Department of Surgery, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan. 7. Department of Colorectal Surgery, National Cancer Center Hospital, Tokyo, Japan. 8. Department of Surgery, Japanese Red Cross Kanazawa Hospital, Kanazawa, Japan. 9. Department of Surgery, Kurume University Faculty of Medicine, Kurume, Japan. 10. Department of Surgery, Yamagata Prefectural Central Hospital, Yamagata, Japan. 11. Department of Surgery, Kamiiida Daiichi General Hospital, Nagoya, Japan. 12. Department of Surgery, National Defense Medical College, Tokorozawa, Saitama, Japan. 13. Department of Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
Abstract
BACKGROUND: A Japanese multicenter study disclosed four prognostic indicators of colorectal cancer liver metastases: ≥5 hepatic tumors (HT), HT size > 5 cm, nodal status (N2) of primary cancer, and the presence of extrahepatic metastases (EM). The Japanese classification was then defined as Stage A, HT1 (≤4 lesions and ≤5 cm) and N0/1; Stage B, HT2 (≥5 lesions or >5 cm) and N0/1, or HT1 and N2; and Stage C, HT2 and N2, HT3 (≥5 lesions and >5 cm) with any N, or EM1 (presence of EM) with any HT/N. This study aimed to validate the prognostic reliability in a recent population and to develop a modified staging system that divided Stage C patients. METHODS: A total of 1185 patients diagnosed with liver metastases between 2007 and 2008 were enrolled in the study. According to the classification, 358, 257, and 570 patients were categorized as Stages A, B, and C, respectively. Stage C was further divided into two groups: Stage C-I, HT3 and N0/1, HT2 and N2, or HT1 and EM1; and Stage C-II, HT3 and N2, or HT2/3 and EM1. RESULTS: Cumulative overall survival curves for Stages A, B, and C were significantly different between each two stages (p < 0.0001, p < 0.0001). The modified system discriminated patients with a relatively better outcome (Stage C-I) from desperate patients (Stage C-II) (p < 0.0001). CONCLUSIONS: The Japanese classification system was adequately validated in a recent population, and the modified system is useful in risk stratification of Stage C cases.
BACKGROUND: A Japanese multicenter study disclosed four prognostic indicators of colorectal cancer liver metastases: ≥5 hepatic tumors (HT), HT size > 5 cm, nodal status (N2) of primary cancer, and the presence of extrahepatic metastases (EM). The Japanese classification was then defined as Stage A, HT1 (≤4 lesions and ≤5 cm) and N0/1; Stage B, HT2 (≥5 lesions or >5 cm) and N0/1, or HT1 and N2; and Stage C, HT2 and N2, HT3 (≥5 lesions and >5 cm) with any N, or EM1 (presence of EM) with any HT/N. This study aimed to validate the prognostic reliability in a recent population and to develop a modified staging system that divided Stage C patients. METHODS: A total of 1185 patients diagnosed with liver metastases between 2007 and 2008 were enrolled in the study. According to the classification, 358, 257, and 570 patients were categorized as Stages A, B, and C, respectively. Stage C was further divided into two groups: Stage C-I, HT3 and N0/1, HT2 and N2, or HT1 and EM1; and Stage C-II, HT3 and N2, or HT2/3 and EM1. RESULTS: Cumulative overall survival curves for Stages A, B, and C were significantly different between each two stages (p < 0.0001, p < 0.0001). The modified system discriminated patients with a relatively better outcome (Stage C-I) from desperate patients (Stage C-II) (p < 0.0001). CONCLUSIONS: The Japanese classification system was adequately validated in a recent population, and the modified system is useful in risk stratification of Stage C cases.