Background: Infantile myofibromatiosis (IM) is a rare benign tumor in the infants, but it has a bad prognosis if IM erncroaches on the viscera. Multiple tissues can be invaded by IM, including the subcutaneous tissue, the muscle of the neck, back, and head, but seldom in the bones and the viscera. The histopathologic and immunohistochemical examinations are necessary in daigonosis of IM as it might be misdiagnosed as the malignant tumor.
Materials and method: Thirty-two consecutive patients with IM in our hospital (2003-2013) were enrolled and the clinical date were analyzed to understand IM better, such as the feature of clinical manifestations, pathology, imaging tests, and treatment.
Results: All of them underwent excision operations, 4 of them with invasion in the bones, 2 with invasion in the craniums, and the rest in the ulna and the humerus. The immunohistiochemical analysis shown that the tumor cells were positive to vimentin and smooth muscle actin while negative to the S100 protein and desmin. Twenty-five patients were in follow-up, 2 cases recurred.
Conclusions: IM is a benign tumor, but IM with the viscera involvement has a bad prognosis. The strategy of waiting and observation for IM without visceral involvement could be selected.