title: Novel population-based study finding higher than reported hepatocellular carcinoma incidence suggests an updated approach is needed.
abstract: Hepatocellular carcinoma (HCC) incidence is rising rapidly in many developed countries. Primary epidemiological data have invariably been derived from cancer registries that are heterogeneous in data quality and registration methodology; many registries have not adopted current clinical diagnostic criteria for HCC and still rely on histology for classification. We performed the first population-based study in Australia using current diagnostic criteria, hypothesizing that HCC incidence may be higher than reported. Incident cases of HCC (defined by American Association for the Study of Liver Diseases diagnostic criteria or histology) were prospectively identified over a 12-month period (2012-2013) from the population of Melbourne, Australia. Cases were captured from multiple sources: admissions to any of Melbourne's seven tertiary hospitals; attendances at outpatients; and radiology, pathology, and pharmacy services. Our cohort was compared to the Victorian Cancer Registry (VCR) cohort (mandatory notified cases) for the same population and period, and incidence rates were compared for both cohorts. There were 272 incident cases (79% male; median age: 65 years) identified. Cirrhosis was present in 83% of patients, with hepatitis C virus infection (41%), alcohol (39%), and hepatitis B virus infection (22%) the commonest etiologies present. Age-standardized HCC incidence (per 100,000, Australian Standard Population) was 10.3 (95% confidence interval [CI]: 9.0-11.7) for males and 2.3 (95% CI: 1.8 to 3.0) for females. The VCR reported significantly lower rates of HCC: 5.3 (95% CI: 4.4 to 6.4) and 1.0 (95% CI: 0.7 to 1.5) per 100,000 males and females respectively (P < 0.0001).
  
  
  CONCLUSIONS
  HCC incidence in Melbourne is 2-fold higher than reported by cancer registry data owing to under-reporting of clinical diagnoses. Adoption of current diagnostic criteria and additional capture sources will improve registry completeness. Chronic viral hepatitis and alcohol remain leading causes of cirrhosis and HCC.
authors.affiliation: Department of Gastroenterology & Hepatology:, St Vincent's Hospital, Melbourne, Australia.
authors.forename: Thai P
authors.initials: TP
authors.lastname: Hong
authors.affiliation: The Austin Hospital, Melbourne, Australia.|Melbourne Medical School, University of Melbourne, Melbourne, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Gow
authors.affiliation: Department of Surgery, The Austin Hospital, Melbourne, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Fink
authors.affiliation: Monash Medical Center, Melbourne, Australia.
authors.forename: Anouk
authors.initials: A
authors.lastname: Dev
authors.affiliation: The Alfred Hospital, Melbourne, Australia.
authors.forename: Stuart
authors.initials: S
authors.lastname: Roberts
authors.affiliation: Eastern Health, Melbourne, Australia.|The Royal Melbourne Hospital, Melbourne, Australia.|Eastern Health Clinical School, Monash University, Melbourne, Australia.
authors.forename: Amanda
authors.initials: A
authors.lastname: Nicoll
authors.affiliation: Eastern Health, Melbourne, Australia.|Eastern Health Clinical School, Monash University, Melbourne, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Lubel
authors.affiliation: Western Health, Melbourne, Australia.
authors.forename: Ian
authors.initials: I
authors.lastname: Kronborg
authors.affiliation: Western Health, Melbourne, Australia.
authors.forename: Niranjan
authors.initials: N
authors.lastname: Arachchi
authors.affiliation: Department of Gastroenterology & Hepatology:, St Vincent's Hospital, Melbourne, Australia.
authors.forename: Marno
authors.initials: M
authors.lastname: Ryan
authors.affiliation: The Alfred Hospital, Melbourne, Australia.
authors.forename: William
authors.initials: W
authors.lastname: Kemp
authors.affiliation: Monash Medical Center, Melbourne, Australia.
authors.forename: Virginia
authors.initials: V
authors.lastname: Knight
authors.affiliation: Victorian Cancer Registry, Cancer Council Victoria, Australia.
authors.forename: Helen
authors.initials: H
authors.lastname: Farrugia
authors.affiliation: Victorian Cancer Registry, Cancer Council Victoria, Australia.
authors.forename: Vicky
authors.initials: V
authors.lastname: Thursfield
authors.affiliation: Department of Gastroenterology & Hepatology:, St Vincent's Hospital, Melbourne, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Desmond
authors.affiliation: Department of Gastroenterology & Hepatology:, St Vincent's Hospital, Melbourne, Australia.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Thompson
authors.affiliation: Department of Gastroenterology & Hepatology:, St Vincent's Hospital, Melbourne, Australia.
authors.forename: Sally
authors.initials: S
authors.lastname: Bell
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D015994:Incidence; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D020380:Needs Assessment; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D016012:Poisson Distribution; D011379:Prognosis; D012042:Registries; D017678:Sex Distribution; D018709:Statistics, Nonparametric; D014739:Victoria / Q000453:epidemiology