Soft tissue myxoma manifesting as a slowly growing subcutaneous mass in the anterior chest wall: A case report.

Soft tissue myxomas are benign mesenchymal neoplasms typically found in the intramuscular components of the proximal extremities. However, soft tissue myxomas in the chest wall are rare. We report the case of a 41-year-old woman with soft tissue myxoma who presented with a slowly growing, palpable lump on her left anterior chest wall that has been present for several years. Mammography revealed an oval, circumscribed, and hyperdense mass in the retromammary fat layer of the upper inner quadrant of the left breast. Ultrasonography revealed an oval, circumscribed, and hypoechoic mass with internal echoes and multiple microcystic spaces. A triangular hyperechoic area adjacent to the pole of the mass and peripheral hyperechoic rim were also detected. The patient underwent surgical excision and was diagnosed with soft tissue myxoma with subcutaneous manifestation.