Second Osteosarcoma in a 16-Year-old Woman Diagnosed With Rothmund-Thomson Syndrome.

Rothmund-Thomson syndrome (RTS) is an autosomal recessive disorder associated with an increased predisposition to osteosarcoma (OS) when it is caused by concrete mutations in the RECQL4 gene. Most OSs arise sporadically, but it can also be the first manifestation of a cancer predisposition syndrome as Rothmund Thompson. The early onset, multifocality and metachronism, and a family history of the disease, may suggest a tumor predisposition syndrome. We present the case of a patient with a polymalformative syndrome, who, at 6 years of age, was diagnosed with OS in the right femur. This led to the diagnosis of a RTS type 2. She was cured and surveillance showed no sign of disease. Ten years later, the patient developed a second OS in the contralateral femur. Fortunately, she is in complete remission again after treatment. We describe our patient treatment and recommend a possible screening-surveillance for RTS type II patients.