Suspicious spots on the lungs of children with rhabdomyosarcoma do not behave like metastases

Rhabdomyosarcoma is a malignant soft tissue tumor in the muscle tissue of children and adolescents. About 20 children are diagnosed with rhabdomyosarcoma per year in the Netherlands. "Metastases in these children are often found in the lungs," says professor Hans Merks of the Princess Máxima Center for Pediatric Oncology, who led the study. "We can detect those metastases on CT scans of the lungs. In addition to the easily recognizable metastases, these CT scans regularly show small spots on the lungs. We did not know if these were metastases until now."

To find out what these small spots mean, the team re-examined all CT scans in a large European study of more than 300 children with rhabdomyosarcoma. About 1 in 5 children had these small spots on the lungs. The future prospects of the children with small spots turned out to be just as good as those of children without abnormalities on their lung CT.

"This is good news," says Merks. "It means that these children do not need to be treated with extra strong medicines that are potentially harmful to the heart; they also do not need to be treated for longer or need radiation on their lungs, as is the case when children have larger lung metastases."

Since the chances of survival are high for children with rhabdomyosarcoma, this is important news. A more aggressive treatment often causes problems later in life. This study shows that a more aggressive treatment is not necessary when small spots are visible on the CT scans. This increases the chance of a good quality of life without limitations for ex-patients.