title: Tumor doubling time after initial response to transarterial chemoembolization in patients with hepatocellular carcinoma.
abstract: OBJECTIVE
  Following initial transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC), these tumors can frequently recur, making it important to determine the appropriate follow-up interval after initial response to TACE. We therefore assessed the time taken by new recurrent HCCs to double in volume after an initial response to TACE.
  
  
  METHODS
  This retrospective cohort study included 73 patients who achieved an initial response after TACE. After intrahepatic distant recurrence of HCC, dynamic CT scans were reviewed by two radiologists without clinical information, and the doubling time of new recurrent nodules was determined. The relationship between doubling time and clinical factors was also analyzed.
  
  
  RESULTS
  In 32 of the 73 patients, 40 intrahepatic distant recurrent (IDR) nodules were detected over a median period of 14 months (range 4-46 months). The 1-, 2- and 3-year cumulative IDR rates of patients were 27%, 45% and 65%, respectively. The doubling time of IDR HCC ranged from 20 to 104 days, with a median of 46 days. Over 90% of IDR HCCs had a doubling time of less than 3 months. The doubling time (median 108 days; range 51-129 days) of primary HCC in five patients for whom we had information regarding primary tumors was longer than that of recurrent nodules (median 28 days; range 24-90 days) in the same five patients (P = 0.022).
  
  
  CONCLUSIONS
  The median doubling time of IDR HCCs after an initial response was 47 days (range 20-104 days). These findings indicate that the appropriate follow-up interval for dynamic CT in patients with an initial response after TACE is less than 3 months.
authors.affiliation: Department of Internal Medicine, College of Medicine, Medical Research Institute, Pusan National University, Busan, South Korea.
authors.forename: Hyun Young
authors.initials: HY
authors.lastname: Woo
authors.forename: Jeong Won
authors.initials: JW
authors.lastname: Jang
authors.forename: Jong Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Si Hyun
authors.initials: SH
authors.lastname: Bae
authors.forename: Chan Ran
authors.initials: CR
authors.lastname: You
authors.forename: Sung Eun
authors.initials: SE
authors.lastname: Rha
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Lee
authors.forename: Seung Kew
authors.initials: SK
authors.lastname: Yoon
authors.forename: Chang Don
authors.initials: CD
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000628:therapy*; D002406:Catheterization, Peripheral; D016461:Chemoembolization, Therapeutic; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000628:therapy*; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome