Value Of Liver Cancer Screening Doubtful Says Danish Study
Lead author Dr Peter Jepsen of Aarhus University Hospital and the University of Copenhagen, and colleagues, write about their findings in the June issue of Annals of Internal Medicine.
Alcoholism can lead to cirrhosis or scarring of the liver, such that over time scar tissue replaces healthy tissue and prevents the liver from working properly. The damage is permanent and irreversible and eventually leads to liver failure.
Jepsen and colleagues note that while some studies suggest people with alcoholic cirrhosis have a higher risk of developing liver cancer, and there is a belief screening for the disease can reduce deaths in this population, this is not backed up by evidence from randomized trials because there haven't been any.
So he and his colleagues decided to investigate further by examining a nationwide Danish registry of patients who were admitted to hospital with a first-time diagnosis of alcoholic cirrhosis between 1993 and 2005.
They found that of 8,482 patients diagnosed with alcoholic cirrhosis, 169 developed liver cancer and 5,734 died, 151 of whom had liver cancer.
But they found that the incidence of, and rate of death from, liver cancer was no greater among the alcoholic cirrhosis patients than in the general population.
Jepsen and colleagues conclude that Danish patients with alcoholic cirrhosis have a low risk for liver cancer, and this disease has little impact on the high rate of death in this group.
They note that a potential weakness of the study is that the diagnoses were made by hospital doctors without using a standard set of criteria, and because the analysis used registry data only, there was no information on the clinical care of patients, for instance whether they had undergone screening for liver cancer.
The researchers do not preclude the possibility that a randomized controlled study (comparing, for instance, alcoholic cirrhosis patients randomly assigned to screening and non-screening) might find a different answer, but imply, that for the time being, this is the best answer from the data available.
Thus, on the basis of their findings, they suggest screening for liver cancer "would be expected to have a minimal effect on mortality and is unlikely to be cost-effective".
If there are no clear benefits, then the downsides of screening are heightened. For instance there is always a risk of a false positive, which can then lead to further unnecessary and invasive tests.
In email correspondence with Reuters Health, Jepsen said ultrasound was often the preferred tool for initial liver cancer screening, and if that suggests there could be a tumor present, the patient is referred for a CT scan, which carries the risk of radiation exposure.
Note: this article has been reissued to clarify the first paragraph and remove a confusing point that is already well explained in paragraph 4.
Written by Catharine Paddock PhD