Purpose or Case Report: To review the characteristic imaging findings of pediatric fibroblastic/myofibroblastic masses to aid in their diagnosis and management.
Soft tissue lesions in pediatric patients encompass a wide variety of pathologies. While a comprehensive review of all possible pathologies is beyond the scope of this poster, we aim to review one particular subset of lesions, fibroblastic lesions (including myofibroblastic neoplasms), in hopes to bring these to mind when evaluating a pediatric soft tissue mass to improve diagnosis and management of these entities.
Soft tissue masses typically present clinically on the basis of history and physical examination. US and MRI are used as first- and second-line imaging modalities, with limited roles for radiographs, CT and FDG-PET. In this poster, we will review the pertinent imaging findings of these neoplasms.
Methods & Materials: A literature search was performed to compile a list of pediatric fibroblastic and myofibroblastic neoplasms. Our departmental PACS was searched for relevant cases performed between 2014 and 2024 using commercially available software (mPower, Nuance Communications, Burlington, MA, USA).
Results: Benign masses such as nodular fasciitis are well-defined broadly-based masses at the superficial fascia. Myositis ossificans is a pseudo-inflammatory tumor within muscle typically associated with trauma. Fibromatosis colli typically shows well-circumscribed fusiform thickening in the lower two-thirds of the sternocleidomastoid muscle. Fibroma of tendon sheath is expectedly closely associated with the tendon. Elastofibroma typically located in the infrascapular regions contains fat intermixed with fibroelastic tissue. Fibrous hamartoma of infancy appears as a mobile subcutaneous lesion usually around the trunk or extremities.
Intermediate masses including plantar fibromatosis appear as discrete multinodular thickening of the plantar fascia. Desmoid-type fibromatosis appears as a solid mass at a typical location such as the abdominal wall. Lipofibromatosis is usually an ill-defined mass found in the hands and feet of children. Infantile fibrosarcoma is often a rapidly growing mass or nodule in the first 2 years of life.
Malignant masses like low-grade fibromyxoid sarcoma are usually slow-growing superficial soft tissue masses of the head and neck region.
Conclusions: Fibroblastic and myofibroblastic masses are an important consideration for soft tissue masses in pediatric patients and we hope this review will enlighten the reader to recognize these entities.