Hepatitis C virus
(HCV) infection doubles the relative risk of lymphoid neoplasms, according to
Taiwanese research published in Hepatology.
Investigators compared the incidence of lymphoma-like cancers between matched
people with and without HCV; after taking onto account all
potential confounders, HCV infection was associated with a twofold increase in
the risk of any lymphoid neoplasm, with a similar increase in the risk of
non-Hodgkin's lymphoma (NHL).
“We conducted a
nationwide population-based cohort study to reduce the possibility of selection
bias,” write the authors. “We demonstrated that HCV infection is associated with
a higher risk of any lymphoid neoplasm, especially NHL, after adjustment for
potential confounding variables.”
include non-Hodgkin's lymphoma, Hodgkin's lymphoma, multiple myeloma, acute
lymphoblastic lymphoma and chronic lymphocytic leukaemia. There are some data
suggesting that chronic HCV infection increases the risk of such malignancies.
However, studies examining this association have had a small sample size and a
short period of follow-up.
type of tumour affecting the lymph nodes.
abnormal and uncontrolled growth of tissue; a tumour.
To establish a
clearer understanding of the link between HCV infection and the risk of
lymphoid-neoplasms, investigators in Taiwan designed a prospective cohort
involving people with and without HCV. Patients and controls were
matched according to age, sex and co-morbidity. Data were gathered on the
incidence of any lymphoid neoplasm and non-Hodgkin's lymphoma over six to eight
years of follow-up. The authors conducted a series of analyses to see if HCV
infection increased the risk of these cancers.
The cohort of people with HCV comprised 11,679 individuals who were diagnosed with the
infection between 2001 and 2005. They were matched with 46,716 people who did not have HCV. Previous cancer, infection
with hepatitis B virus and infection with HIV were exclusion criteria.
Mean age was 55
years and 51% of individuals in both cohorts were female. The mean duration of
follow-up was six years for the cohort with HCV and eight years for the cohort without HCV.
During this time,
36 people in the HCV cohort and 83 people in the non-HCV cohort were
diagnosed with lymphoid neoplasms. Most of these were non-Hodgkin's lymphoma (77%
in HCV cohort; 80% non-HCV cohort).
The incidence rate
for any lymphoid-neoplasm was significantly higher in the HCV cohort compared
to the non-HCV cohort (48 vs 22 per 100,000 person-years; p < 0.0001).
non-Hodgkin lymphoma was also higher in the HCV cohort than in the
non-HCV cohort (37 vs 17.5 per 100,000 person-years; p = 0.0008).
Average time from
entry into follow-up and diagnosis with a malignancy was significantly shorter
for the HCV patients compared to people in the non-HCV group (3.1 vs 4.6
years; p = 0.002).
for potential confounders, HCV infection was associated with a more than
twofold increase in the risk of any lymphoid-neoplasm (HR = 2.30; 95% CU,
1.55-3.43; p < 0.0001) and a two-fold increase in the risk of non-Hodgkin's
lymphoma (HR = 2.00; 95% CI, 1.27-3.16; p < 0.003). These findings remained
robust in a sensitivity analysis that excluded people who developed cancer within
the first year after recruitment and also in an analysis that included people
There were some
data suggesting that HCV therapy reduces the risk of lymphoid-neoplasms.
Overall, 9% of people with HCV received interferon-based therapy. Incidence
of any lymphoid-neoplasm was 16 per 100,000 person-years in these patients compared
to 52 per 100,000 person-years in people who were not treated. None of the treated
patients developed non-Hodgkin's lymphoma, but incidence of this cancer was 41
per 100,000 person-years in the patients who did not receive therapy.
population-based cohort study with longitudinal follow-up found that HCV
infection is associated with a greater risk of lymphoid-neoplasms, especially
NHL,” conclude the investigators. “Additional large studies are necessary to
explore whether anti-HCV therapy can reduce the incidence of lymphoid