Survivors of Wilms Tumor remain at risk for death due to late effects

Despite an improved survival outlook over time, patients who survive Wilms Tumor are at elevated risk for death years after their original diagnosis, according to data from the National Wilms Tumor Study.

Specifically, risk for death due to second malignant neoplasms remains elevated for as many as 20 years after diagnosis.

Researchers assessed patients enrolled in the National Wilms Tumor Study between 1969 and 1995; patients were followed until 2002. Using medical records, deaths were classified as result of original disease, late effects or other causes.

The analysis included 6,185 patients; 80% were followed for five or more years post-diagnosis. During the first five years of follow-up, 819 deaths occurred; 159 deaths were reported after that. As of Jan. 1, 2002, 2,870 five-year survivors were known to be alive.

The first five years after diagnosis had the highest standardized mortality ratio: 24.3 (95% CI, 22.6-26.0). The standardized mortality ratio decreased to 12.6 (95% CI, 10.0-15.7) for years five to 10 and to 3.0 thereafter.

According to the researchers, for deaths in the first five years, the risk for mortality decreased at a rate ratio of 0.78 per five-year calendar period of diagnosis. Late effects of treatment or disease were the cause of 62 deaths among five-year survivors, including 27 deaths due to second malignant neoplasms. There was also a trend for decreased risk with calendar period of diagnosis for late-effects mortality (RR=0.86; 95% CI, 0.67-1.10) and second malignant neoplasm mortality (RR=0.82; 95% CI, 0.55-1.21). – by Stacey L. Adams

J Clin Oncol. 2009;doi:10.1200/JCO.2008.18.6981

The treatment of Wilms tumor is one of the great success stories in pediatric oncology. Based on excellent short-term survival rates, some pediatric oncologists have become complacent about this disease and counsel patients that 'Wilms tumor is one of the best cancers to have.' This article highlights that the standardized mortality ratio for patients with Wilms tumor is elevated for many years after the original diagnosis. The greatest risk is within the first five years after diagnosis, related mainly to the primary disease and acute complications of treatment. However, the increased mortality risk persists in long-term survivors due to late effects of treatment such as second malignant neoplasms, heart failure and renal disease. The data suggest a trend toward decreased late effect mortality in more recently treated patients, perhaps due to reductions in radiation therapy and doxorubicin dosages. However, even patients treated with 'modern' treatment regimens have late effects of therapy; it is premature to declare 'mission accomplished.'

– Jeffrey Dome, MD

Division Chief, Oncology,
Children's National Medical Center, Washington, DC