Reviewers: Kenneth Blank, MD
Source: International Journal of Radiation Oncology, Biology and Physics, Vol 42 No. 2 p.373
Great strides have been made in treating childhood cancer. Today, the majority of children diagnosed with cancer will live longer than five years. Unfortunately, their survival is bringing to light the side effects of successful treatment. Possibly the most concerning side effect is the development of a second cancer. Radiation and chemotherapy can both contribute to the development of a second cancer. The incidence of second cancers after these treatments for pediatric lymphomas is a topic of great concern, and the subject of this paper.
An article in the September 1, 1998 issue of the International Journal of Radiation Oncology, Biology and Physics reports on 202 (129 male, 73 female) patients who had been treated with radiotherapy for Hodgkin's disease. All patients were treated between the years 1970 and 1979 at Helsinki University Central Hospital and completed therapy from thirteen to twenty-six years prior to this study. One third of these patients received chemotherapy in addition to the radiation.
Twenty-seven patients developed a second cancer in the follow-up time. Lung cancer was found to be the most common second cancer followed by breast cancer. Seventy-seven percent of the second cancers occurred within or adjacent to the area that received radiation. The cumulative risk of developing a second cancer was estimated to be 17% at twenty years from the diagnosis of Hodgkin's disease.
To better understand the factors which may predict the development of a second cancer, the authors performed univariate and multivariate analysis. Surprisingly, neither the size of the radiation field nor the inclusion of chemotherapy predicted for a second cancer. On multivariate analysis, predictive factors for a second cancer included older age, treatment for recurrent lymphoma, and treatment without splenectomy.
The high incidence of second cancer in this patient population is very concerning. It highlights the necessity for long-term follow up after curative treatment for Hodgkin's disease that must include careful examination for a second cancer.