Spontaneous Regression In A Patient With Infantile Fibrosarcoma
Sait, S. F., Danzer, E., Ramirez, D., LaQuaglia, M. P., & Paul, M. (2018). Spontaneous Regression in a Patient With Infantile Fibrosarcoma. Journal of pediatric hematology/oncology, 40(4), e253–e255. https://doi.org/10.1097/MPH.0000000000001013
View Original Source →Abstract
Infantile fibrosarcoma usually presents as a rapidly growing mass on the extremities or trunk. We describe spontaneous regression in a 5-month-old female infant with biopsy proven, molecularly confirmed, right leg infantile fibrosarcoma currently at 26 months of age with no signs of local recurrence. Previously reported cases of spontaneous regression are reviewed, suggesting a benign clinical course in some cases. Although evidence for spontaneous regression is anecdotal in this rare tumor type, physicians should weigh the risks and benefits of surgery and chemotherapy against watchful waiting.
Case Details
Disease Location
Muscle
Personal Characteristics
5-month-old infant
Clinical Characteristics
Presented with a lump on the right ankle, which was progressively increasing in size for 1 month but was not painful. Physical exam demonstrated a firm, non-tender mass in the anterolateral aspect of the right ankle, extending from the right lateral ankle to mid upper third of the leg, 4 × 4 cm in size. MRI demonstrated the presence of a well-circumscribed intramuscular mass with well-defined peripheral margins measuring 2.3 cm × 1.9 cm × 5.6 cm. The mass involved the extensor digitorum longus and external hallucis longus muscles and was causing posterior bowing of the interosseus membrane and scalloping of fibula. Core needle biopsy showed a spindle cell neoplasm with slightly irregular ovoid to epithelioid cells with hyperchromatic nuclei, frequent intranuclear vacuoles, and rare nucleoli with mild cellular pleomorphism. Fluorescent in situ hybridization (fish) studies showed rearrangement of the etv6 gene. These findings confirmed the diagnosis of infantile fibrosarcoma (ifs)
Remission Characteristics
Four months following diagnosis, the mass appeared to be decreasing in size following the biopsy. 6 weeks later, MRI showed that the tumor was stable in size and now appeared more cystic and necrotic. The tumor started to shrink thereafter and by the age of 24 months, was impalpable
Treatment & Mechanisms
Proposed Remission Mechanisms
In patients diagnosed with ifs during the first 6 months of life, a more benign clinical course is possible
Clinical Treatment
Biopsy
Non-Clinical Treatment
None reported