title: Predictive factors for late recurrence in patients with stage T1 clear cell renal cell carcinoma: a multiinstitutional study.
abstract: BACKGROUND
  The purpose of this study was to identify predictive factors for late recurrence in Korean patients with stage T1 clear cell renal cell carcinoma (RCC) more than 5 years after treatment with radical nephrectomy (RN) or partial nephrectomy (PN).
  
  
  METHODS
  Between 1999 and 2011, 3567 patients with RCC underwent RN or PN at 5 institutions in Korea. Of these, 423 patients with pathologically confirmed stage T1 clear cell RCC remained free of disease for at least 5 years. To determine the pathologic and clinical factors that influenced late recurrence, univariate and multivariate analyses using the Cox proportional hazards model were performed. Recurrence-free survival curves were estimated by using the Kaplan-Meier method.
  
  
  RESULTS
  During a median follow-up period of 83.9 months (range 60.0-156.4 months), late recurrence was observed in 14 of the 423 (3.3%) patients. Univariate and multivariate analyses revealed that symptoms at diagnosis and pathologic T stage were independent predictive factors for late recurrence. Patients with symptoms at diagnosis or stage T1b disease had a significantly shorter time to late recurrence than did those who were asymptomatic or had stage T1a disease (log-rank test P = .027 and P = .034, respectively).
  
  
  CONCLUSIONS
  Late recurrence in stage T1 clear cell RCC is a relatively rare event. Predictive factors for late recurrence were identified in the present study. Careful long-term follow-up is necessary, especially in patients who have symptoms at diagnosis or stage T1b tumors, even if they have been free of disease for more than 5 years.
authors.affiliation: Department of Urology, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Yun-Sok
authors.initials: YS
authors.lastname: Ha
authors.forename: Yong Hyun
authors.initials: YH
authors.lastname: Park
authors.forename: Seok Ho
authors.initials: SH
authors.lastname: Kang
authors.forename: Sung-Hoo
authors.initials: SH
authors.lastname: Hong
authors.forename: Tae-Kon
authors.initials: TK
authors.lastname: Hwang
authors.forename: Seok-Soo
authors.initials: SS
authors.lastname: Byun
authors.forename: Yong-June
authors.initials: YJ
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D002292:Carcinoma, Renal Cell / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D007680:Kidney Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D009392:Nephrectomy; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult