Smoking ups risk of virus-related Hodgkin lymphoma

Smoking increases the risk of Hodgkin's lymphoma in general and the risk of Epstein-Barr virus-positive Hodgkin's lymphoma in particular, a study published in the journal Epidemiology shows.

Hodgkin's lymphoma is a cancer of the body's lymphatic system, characterized by enlargement of the lymph nodes, spleen, and liver and progressive anemia. Previous reports have linked Epstein-Barr virus, the cause of mononucleosis, with Hodgkin's lymphoma.

In the present study, Dr. Eleanor V. Willett of the University of York, UK and colleagues assessed the link between tobacco smoking, alcohol consumption, Epstein-Barr virus-positive and Epstein-Barr virus-negative Hodgkin's lymphoma in patients between the ages of 16 and 66 living in a defined region of the UK around Yorkshire and Leeds.

The study involved 262 patients with Hodgkin's lymphoma and 262 similar subjects without lymphoma. Another 875 subjects from a study of non-Hodgkin's lymphoma, belonging to another category of lymphomas, were used for comparison.

Past and current smokers were 40 and 70 percent more likely, respectively, to develop Hodgkin's lymphoma than non-smokers. "Associations were suggested for Epstein-Barr virus-positive Hodgkin's lymphoma" but not for virus-negative cases, Willett's team says.

The investigators found no association between alcohol consumption and Hodgkin's lymphoma.

Smoking tobacco is known to suppress the immune system and the interaction with Epstein-Barr virus-infected cells lead to Hodgkin's lymphoma, the investigators speculate.

Whatever the reason, "the public health message is that smoking may be a preventable risk factor for Epstein-Barr virus-positive Hodgkin's lymphoma tumors," they conclude.

SOURCE: Epidemiology, January 2007.