title: Changing Odds of Survival Over Time among Patients Undergoing Surgical Resection of Gallbladder Carcinoma.
abstract: While survival after malignancies is traditionally reported as actuarial survival, conditional survival (CS) may be more clinically relevant by accounting for "accrued" survival time as time progresses. We sought to compare actuarial and CS among patients with gallbladder carcinoma (GBC) .
  
  
  
  A total of 312 patients who underwent curative intent surgery for GBC between 2000 and 2014 were identified using a multi-institutional database. Overall survival (OS) was estimated using the Kaplan-Meier method. CS was calculated as the probability of surviving an additional 3 years at year "x" after surgery using the formula CS3= S(x+3)/Sx.
  
  
  
  Among all patients, the median actuarial OS was 24.8 months (IQR 13.3-88.9). While actuarial survival decreased over time, 3-year CS (CS3) increased, with CS3at 2 years after surgery noted to be 61.8 % compared with the 5-year actuarial OS of 31.6 %. Factors associated with reduced actuarial OS were positive margin status (HR 3.61, 95 % CI 2.47-5.26), increasing tumor size (HR = 1.02, 95 % CI 1.01-1.02), higher tumor grade (HR 2.98, 95 % CI 1.47-6.04), residual disease at repeat resection (HR = 2.78, 95 % CI 1.49-3.49, p < 0.001), and lymph node metastasis (HR = 1.95, 95 % CI 1.39-2.75, all p < 0.001). The calculated CS3exceeded the actuarial survival within each high-risk patient subgroup. For example, patients with residual disease at repeat resection had an actuarial survival 23.1 % at 5 years versus a CS3of 56.3 % in patients alive at 2 years (Δ = 33.2 %).
  
  
  
  CS provides a more accurate, dynamic estimate for survival, especially among high-risk patients. CS estimates can be used to accurately predict survival and guide clinical decision making.
authors: Department of Surgery, Johns Hopkins Hospital, Baltimore, MD, USA.
authors: Stefan
authors: S
authors: Buettner
authors: Department of Surgery, Johns Hopkins Hospital, Baltimore, MD, USA.
authors: Georgios Antonios
authors: GA
authors: Margonis
authors: Department of Surgery, Johns Hopkins Hospital, Baltimore, MD, USA.
authors: Yuhree
authors: Y
authors: Kim
authors: Department of Surgery, Johns Hopkins Hospital, Baltimore, MD, USA.
authors: Faiz
authors: F
authors: Gani
authors: Department of Surgery, Emory University School of Medicine, Atlanta, GA, USA.
authors: Cecilia G
authors: CG
authors: Ethun
authors: Department of Surgery, Stanford University Medical Center, Stanford, CA, USA.
authors: George A
authors: GA
authors: Poultsides
authors: Department of Surgery, Stanford University Medical Center, Stanford, CA, USA.
authors: Thuy
authors: T
authors: Tran
authors: Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.
authors: Kamran
authors: K
authors: Idrees
authors: Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.
authors: Chelsea A
authors: CA
authors: Isom
authors: Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA.
authors: Ryan C
authors: RC
authors: Fields
authors: Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA.
authors: Bradley
authors: B
authors: Krasnick
authors: Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
authors: Sharon M
authors: SM
authors: Weber
authors: Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
authors: Ahmed
authors: A
authors: Salem
authors: Department of Surgery, University of Louisville, Louisville, KY, USA.
authors: Robert C G
authors: RC
authors: Martin
authors: Department of Surgery, University of Louisville, Louisville, KY, USA.
authors: Charles R
authors: CR
authors: Scoggins
authors: Department of Surgery, Wake Forest University, Winston-Salem, NC, USA.
authors: Perry
authors: P
authors: Shen
authors: Department of Surgery, Wake Forest University, Winston-Salem, NC, USA.
authors: Harveshp D
authors: HD
authors: Mogal
authors: Department of Surgery, Ohio State University, Columbus, OH, USA.
authors: Carl
authors: C
authors: Schmidt
authors: Department of Surgery, Ohio State University, Columbus, OH, USA.
authors: Eliza
authors: E
authors: Beal
authors: Department of Surgery, New York University, New York, NY, USA.
authors: Ioannis
authors: I
authors: Hatzaras
authors: Department of Surgery, New York University, New York, NY, USA.
authors: Rivfka
authors: R
authors: Shenoy
authors: Department of Surgery, Emory University School of Medicine, Atlanta, GA, USA.
authors: Shishir K
authors: SK
authors: Maithel
authors: Department of Surgery, Johns Hopkins Hospital, Baltimore, MD, USA. tpawlik1@jhmi.edu.
authors: Timothy M
authors: TM
authors: Pawlik
mesh_terms: D000206:Actuarial Analysis; D000368:Aged; D002277:Carcinoma / Q000401:mortality* / Q000556:secondary / Q000601:surgery*; D005260:Female; D005706:Gallbladder Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D008297:Male; D000072662:Margins of Excision; D008875:Middle Aged; D060787:Neoplasm Grading; D018365:Neoplasm, Residual; D011336:Probability; D016016:Proportional Hazards Models; D012086:Reoperation; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D013997:Time Factors; D047368:Tumor Burden