Haruhisa Matsuguma1, Mingyon Mun2, Atsushi Sano3, Ichiro Yoshino4, Hiroshi Hashimoto5, Yasushi Shintani6, Tomohiko Iida7, Satoshi Shiono8, Masayuki Chida9, Hiroaki Kuroda10, Mitsuo Nakayama11, Yuji Shiraishi12, Kazuhito Funai13, Masafumi Kawamura14. 1. Division of Thoracic Surgery, Tochigi Cancer Center, Tochigi, Japan. hmatsugu@tochigi-cc.jp. 2. Department of Thoracic Surgical Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan. 3. Division of Chest Surgery, Department of Surgery, Toho University School of Medicine, Tokyo, Japan. 4. Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan. 5. Department of Thoracic Surgery, National Defense Medical College, Saitama, Japan. 6. Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan. 7. Department of Thoracic Surgery, Kimitsu Central Hospital, Chiba, Japan. 8. Department of Thoracic Surgery, Yamagata Prefectural Central Hospital, Yamagata, Japan. 9. Department of General Thoracic Surgery, Dokkyo Medical University, Tochigi, Japan. 10. Department of Thoracic Surgery, Aichi Cancer Center Hospital, Aichi, Japan. 11. Department of General Thoracic Surgery, Saitama Medical Center, Saitama, Japan. 12. Section of Chest Surgery, Fukujuji Hospital, Tokyo, Japan. 13. First Department of Surgery, Hamamatsu University School of Medicine, Shizuoka, Japan. 14. Division of General Thoracic Surgery, Department of Surgery, Teikyo University School of Medicine, Tokyo, Japan.
Abstract
BACKGROUND: Probability of cure is important for patients with lung metastasis who must decide whether to undergo metastasectomy. Although progression-free survival (PFS) is thought to reflect this, it does not include curative effects by repeat metastasectomy. Thus, the authors developed a new indicator, time to incurable recurrence (TTIR), in which only incurable recurrence was set as an event that included death, with incurable recurrence defined as recurrence not treated by definitive local therapy (DLT), recurrence treated by DLT but with PFS maintained less than 2 years, or recurrence followed by re-recurrence. METHODS: This multi-institutional study included 339 patients who underwent lung metastasectomy for colorectal cancer between 1990 and 2008. RESULTS: Among the 339 patients, 191 experienced recurrence, 77 received DLT for recurrence, 38 had a PFS of 2 years or longer after the treatment, and 33 had maintained a PFS at the last follow-up date. The patients had PFS ranging from 39 to 212 months (median, 101 months). The 5-year OS, PFS, and TTIR rates were respectively 63.4%, 42.2%, and 51.9%. The TTIR curve was similar to the OS curve 7 years after the initial metastasectomy. The difference between TTIR and PFS at 7 years was 9.7%, indicating probability of cure by repeat DLT. Multivariable analysis showed different prognostic factors among OS, PFS, and TTIR. CONCLUSION: At the initial metastasectomy, TTIR may reflect probability of a cure, including cure by repeat DLT, and can be used to analyze prognostic factors associated with cure.
BACKGROUND: Probability of cure is important for patients with lung metastasis who must decide whether to undergo metastasectomy. Although progression-free survival (PFS) is thought to reflect this, it does not include curative effects by repeat metastasectomy. Thus, the authors developed a new indicator, time to incurable recurrence (TTIR), in which only incurable recurrence was set as an event that included death, with incurable recurrence defined as recurrence not treated by definitive local therapy (DLT), recurrence treated by DLT but with PFS maintained less than 2 years, or recurrence followed by re-recurrence. METHODS: This multi-institutional study included 339 patients who underwent lung metastasectomy for colorectal cancer between 1990 and 2008. RESULTS: Among the 339 patients, 191 experienced recurrence, 77 received DLT for recurrence, 38 had a PFS of 2 years or longer after the treatment, and 33 had maintained a PFS at the last follow-up date. The patients had PFS ranging from 39 to 212 months (median, 101 months). The 5-year OS, PFS, and TTIR rates were respectively 63.4%, 42.2%, and 51.9%. The TTIR curve was similar to the OS curve 7 years after the initial metastasectomy. The difference between TTIR and PFS at 7 years was 9.7%, indicating probability of cure by repeat DLT. Multivariable analysis showed different prognostic factors among OS, PFS, and TTIR. CONCLUSION: At the initial metastasectomy, TTIR may reflect probability of a cure, including cure by repeat DLT, and can be used to analyze prognostic factors associated with cure.