October 12, 2005

Lymphoma risk higher with family history of blood cancer

NEW YORK (Reuters Health) - Having a family history of
hematopoietic malignancy -- cancers of the blood or bone
marrow, such as leukemia and lymphoma -- roughly doubles a
person's risk of developing the most common types of lymphoma
-- non-Hodgkin lymphoma and Hodgkin lymphoma, a new study

Some studies have suggested that malignant lymphomas are
more common among people with a family history of cancer of the
blood, but much of this research has been limited by small
sample size and reliance on self-reporting for information on
family history, researchers note in the Journal of the National
Cancer Institute.

To get a clearer picture of the magnitude of increased
risk, Dr. Ellen T. Chang of the Karolinska Institute in
Stockholm and her colleagues used validated family data from
the Swedish Multi-Generation Register and Cancer Register
including 1506 lymphoma patients and 1229 cancer-free controls.

The researchers found that having a mother, sister or other
"first-degree" relative with a blood cancer was associated with
an approximately two-fold increased risk of non-Hodgkin or
Hodgkin lymphoma.

The researchers found no difference in the effect of
several environmental factors, such as occupational exposure to
organic solvents or pesticides, body mass index, cigarette
smoking and homosexual intercourse, on non-Hodgkin lymphoma
risk based on whether the disease was familial or "sporadic."

SOURCE: Journal of the National Cancer Institute, October
5, 2005.