A rare case of neonatal-onset infantile myofibromatosis with metastatic recurrence in adulthood

Infantile myofibromatosis (IM) is a rare mesenchymal disorder, typically observed during infancy and characterized by the development of myofibroblastic tumors within skin, muscle, bone or viscera. In most cases, spontaneous regression of the lesions occurs before the age of four, however therapeutic tools such as surgery and chemotherapy sometimes need to be implemented. Metastatic recurrence of this condition is very rare. We report the case of a newborn infant with multicentric IM involving the skin, intestinal tract and bone, who required long-term symptomatic treatment. Spontaneous regression was noticed at the age of four but twenty years later she presented with a complete spontaneous right pneumothorax revealing cystic pulmonary metastases of IM. There have been very few reports of metastatic recurrence of IM in adulthood and this unique presentation underlines the need for long-term follow-up of these patients to detect and prevent possible complications.