18F-FDG PET/CT Imaging of Metastatic Atypical Fibroxanthoma

Abstract

We report the F-FDG PET/CT appearance of a metastatic biopsy-proven malignant fibroxanthoma of the ankle. A 41-year-old female patient with a history of scleroderma presented with a fungating mass in the left ankle. Shave biopsy of the overlying skin showed atypical fibroxanthoma (AFX). Staging FDG PET/CT demonstrated a hypermetabolic exophytic soft tissue mass in the left ankle with local extension to bone and widespread metastatic disease including pulmonary parenchyma, nodes, bone marrow, and skeletal muscle. While rare, knowledge of the potential aggressive nature of AFX is important for accurate diagnosis.

Atypical fibroxanthoma management: Recurrence, metastasis and disease‐specific death

“…Similarly, six reported cases of metastatic AFX were re‐diagnosed as UPS/MFH, thought likely to be UPS/MFH, or were suspected of being UPS/MFH based on patient demographics, tumour and pathological description and behaviour . UPS requires a different management approach to AFX considering this dissimilarity in behaviour.…”

Surgical excision margins for fibrohistiocytic tumors, including atypical fibroxanthoma and undifferentiated pleomorphic sarcoma: A probability model based on a systematic review

“…In such cases, ultrasound, computed tomography, and magnetic resonance imaging have been used for presurgical planning. 66,67 Follow-up typically entails full-body skin examination, including particularly careful examination of the surgical site, and palpation of the regional lymph nodes. Follow-up may be frequently performed in the first 2 years after diagnosis and less frequently yearly thereafter for 5 to 10 years.…”

Atypical Fibroxanthoma: An unexpected cause of hemoptysis

“…Pulmonary metastasis from cutaneous atypical fibroxanthoma was described for the first time in 2003 by Kargi et al [5]. Very few cases report that this neoplasm rarely metastasises to lymph nodes, parotid glands, bone marrow, skeletal muscles, brain and lungs [3,5,[9][10]. In addition, pulmonary, brain and liver metastases have been noticed in cases with minimal or no subcutaneous involvement [11].…”

“…Sheth et al reported a case of a 41-year-old woman with atypical fibroxanthoma of her left ankle. Staging fluorodeoxyglucose positron emission tomography (FDG PET)/CT revealed local extension of the lesion to bone and metastases to lung parenchyma, lymph nodes, bone marrow and muscles [9]. Satter et al described a case of a 63-year-old man with the diagnosis of atypical fibroxanthoma on his left temple that was completely resected with Mohs micrographic surgery.…”