Stroke risk in cancer survivors

Research shows that survivors of Hodgkin's disease are 2- to 3-times more likely to suffer a stroke or mini-stroke, also known as transient ischaemic attack (TIA) compared with people in the general population.

Hodgkin's disease, also known as Hodgkin's lymphoma, is a cancer of the lymphatic system, a part of the immune system. Compared with some other types of lymphoma, Hodgkin's lymphoma usually responds to treatment and most patients can be cured. As the disease frequently affects children and young adults, there is a prolonged period during which long-term side effects can develop.

Researchers from Netherlands studied 2,201 five-year survivors of Hodgkin's lymphoma who were treated before they were 51 years old (from 1965 to 1995) to find out the long-term influence of treatment for Hodgkin's lymphoma on the incidence of stroke and transient ischaemic attack.

During a median follow-up period of 17 years, 55 patients suffered a stroke, 31 had a TIA, and 10 had both. Much of the increased risk was related to radiation therapy of the neck and mediastinum, the space in the chest behind the sternum (breastbone) between the lungs.

Relative to the general population, Hodgkin's lymphoma survivors were 2 and 3 times more likely to experience a stroke or TIA, respectively. Moreover, little change in these risks was noted after a prolonged follow-up. Thirty years following treatment for Hodgkin's lymphoma, the cumulative incidence of stroke or TIA was 7%.

Receipt of radiation therapy to the head and neck independently raised the risk of stroke more than two-fold. Radiation exposure to the neck might be expected to cause narrowing or stenosis of the carotid arteries in the neck, which, in turn, would increase the risk of stroke and TIA. Chemotherapy was not significantly linked with a high risk of stroke or TIA. However, other factors increasing the risk of stroke and TIA included high blood pressure, diabetes, and high cholesterol levels.

The researchers suggested that for cancer survivors who were at risk of stroke and TIA, their physicians should consider appropriate risk-reducing strategies, such as treatment of hypertension (high blood pressure) and lifestyle changes to reduce this risk.