Ollier disease

Ollier disease, also known as enchondromatosis, is a rare skeletal disorder characterized by the development of multiple enchondromas — benign cartilaginous tumors that arise within the medullary cavity of bones. These enchondromas predominantly affect the metaphyses and diaphyses of long bones, particularly in the hands, feet, and long bones of the limbs, and tend to be distributed asymmetrically, often with unilateral predominance. The condition typically presents in childhood, when affected individuals develop painless bony masses, limb length discrepancies, skeletal deformities, and pathological fractures. Ollier disease is caused by somatic mosaic mutations, most commonly in the IDH1 or IDH2 genes, which encode isocitrate dehydrogenase enzymes. Because the mutations are postzygotic (somatic), the condition is not inherited in a classic Mendelian pattern and occurs sporadically. The primary clinical concern in Ollier disease is the risk of malignant transformation of enchondromas into chondrosarcomas, which occurs in an estimated 25–30% of patients over their lifetime. Other malignancies, including gliomas and juvenile granulosa cell tumors of the ovary, have also been reported at increased frequency. When enchondromas are accompanied by soft tissue hemangiomas, the condition is classified as Maffucci syndrome, which carries an even higher risk of malignant transformation. The skeletal system is the most significantly affected body system, though secondary complications can involve the central nervous system and reproductive organs. There is no curative treatment for Ollier disease. Management is primarily supportive and symptomatic, focusing on orthopedic interventions such as surgical curettage of symptomatic enchondromas, correction of limb length discrepancies, and treatment of pathological fractures. Long-term surveillance with clinical examination and imaging is essential to monitor for signs of malignant transformation, including sudden increase in size, new onset of pain, or cortical destruction on imaging. Patients require lifelong follow-up by a multidisciplinary team including orthopedic surgeons, oncologists, and geneticists.

Common questions about Ollier disease