Characterization of metastatic angiomatoid fibrous histiocytoma

Angiomatoid Fibrous Histiocytoma of the Chest Wall Protruding into the Thoracic Cavity Mimicking Metastasis in a Patient with Breast Cancer

Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue tumor of intermediate malignancy and uncertain differentiation. To date, only four patients diagnosed with AFH located in the chest wall have been described. Herein, we describe a 44-year-old woman diagnosed with breast infiltrating lobular carcinoma. During the imaging study with positron emission tomography-computerized tomography scan, a 4 cm solid lesion located in the chest wall was identified. Fine-needle aspiration followed by surgical excision with intraoperative frozen section study was performed. The combined histomorphologic, immunohistochemical, and molecular findings confirmed the diagnosis of AFH. In this report, we describe, to the best of our knowledge, the first patient with synchronous AFH and breast cancer.

Pulmonary Metastasising Aneurysmal Fibrous Histiocytoma: A Case Report, Literature Review and Proposal of Standardised Diagnostic Criteria

An aneurysmal fibrous histiocytoma is a rare cutaneous soft-tissue tumour which accounts for approximately 0.06% of all dermatopathologies. Metastasis is exceedingly uncommon, to the point that there have only been eight reported cases in the scientific literature. We present the case of a 25-year-old male with a primary aneurysmal fibrous histiocytoma located in the nuchal region which exhibited rapid growth and abrupt ulceration over a short time span and showed signs of locoregional aggressive infiltration. A subsequent histopathological analysis confirmed the presence of diffuse solid and cystic pulmonary metastases. Further genetic sequencing verified LAMTOR1-PRKCD fusion. This case report seeks to review the existing literature on aneurysmal fibrous histiocytoma, discuss the challenges of differential diagnosis and propose standardised diagnostic criteria.

Evidence of Chemoresponsiveness in Unresectable Metastatic Angiomatoid Fibrous Histiocytoma

Angiomatoid fibrous histiocytoma (AFH) is a soft tissue neoplasm of intermediate biological potential. Typically a slow-growing tumor, it can recur locally. Rarely, it manifests as a soft tissue sarcoma capable of metastasis. When metastases are nonamenable to local therapy, it is believed uniformly fatal. We present 3 patients with metastatic AFH who demonstrated a sustained response to chemotherapy; including one who achieved complete remission with cryoablation. These cases reinforce the potential value of chemotherapy in some patients with unresectable metastatic AFH and provide the first case in the literature of cryoablation in AFH.

Angiomatoid Fibrous Histiocytoma (AFH) of the Right Arm: An Exceptional Case with Pulmonary Metastasis and Confirmatory EWSR1::CREB1 Translocation

Angiomatoid fibrous histiocytoma (AFH) is a rare neoplasm described for the first time by Enzinger in 1979, and classified by World Health Organization 2020 as intermediate malignant potential neoplasm. It mostly occurs in the subcutis and is characterized by varying proportions of epithelioid, ovoid and spindle cells in a nodular and syncytial growth pattern, with some hemorrhagic pseudovascular spaces. In this paper, we report the clinical case of a 62-year-old man who presented with AFH on the right arm, and relapsed three years after first surgical excision. After a further three years, the patient presented with an intramuscular localization of AFH, and 12 months after this, a pulmonary metastasis of AFH was diagnosed. Given the rarity of the spreading of AFH, we performed Fluorescence In Situ Hybridization (FISH) and we detected EWSR1::CREB1 gene fusion.

Intracranial angiomatoid fibrous histiocytoma with rhabdoid features: a mimic of rhabdoid meningioma

Angiomatoid fibrous histiocytoma (AFH) is an uncommon soft-tissue neoplasm that arises mostly in the extremities of young people and generally carries a good prognosis. Intracranial location is unusual and frequently associated with myxoid change. EWSR1 gene fusions with members of the CREB family (CREB1, ATF1, and CREM) are well-established events in AFH. These fusions have also been described in other neoplasms including intracranial myxoid mesenchymal tumor, and it is still uncertain whether the latter is a distinct entity or if it represents a myxoid variant of AFH. Here, we describe a rare falcine AFH presenting in a 50-year-old woman. The most striking feature of this tumor was its diffuse rhabdoid morphology with focal high mitotic activity, raising the consideration of rhabdoid meningioma (WHO grade III). The tumor cells were moderately positive for EMA and negative for progesterone receptor and SSTR2 prompting additional studies. Desmin was strongly positive and CD99 showed membranous immunoreactivity. BAP1, INI-1, and BRG1 expressions were retained. Next-generation sequencing analysis demonstrated an EWSR1-ATF1 gene fusion, supporting the diagnosis of an unusual rhabdoid variant of AFH. After gross total resection of this tumor, the patient remains free of disease 5 months after the surgery without additional treatment.

Therapeutic response of metastatic angiomatoid fibrous histiocytoma carrying EWSR1-CREB1 fusion to the interleukin-6 receptor antibody tocilizumab

Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue tumor that has been associated with EWSR1-CREB1 gene fusion. Outcome in patients with unresectable distant metastases is generally fatal. Interleukin-6 (IL-6) secretion has been described in tumors with EWSR1-CREB1 fusion, and may promote tumor growth due to autocrine stimulation. Tocilizumab is an IL-6 receptor antibody that has potential benefit as a targeted therapy in refractory neoplasms with IL-6 secretion. We describe a child with metastatic AFH with EWSR1-CREB1 fusion and elevated IL-6 whose disease progressed during treatment with traditional chemotherapeutic agents, but improved after targeted therapy with tocilizumab.

Primary angiomatoid fibrous histiocytoma of the lung with mediastinal lymph node metastasis

Angiomatoid fibrous histiocytoma (AFH), a rare soft tissue tumor of borderline malignancy, typically occurs in the subcutis of the accessible soft tissues, most often in children and young adults. Lymph node and/or distant metastasis is seen in less than 2% of patients with AFH. Exceptionally rare examples of AFH have been reported in visceral locations, including the lung. We report a genetically confirmed primary pulmonary AFH in a 70-year-old woman with mediastinal lymph node metastasis, representing to the best of our knowledge the first report of metastases from a visceral AFH.

Angiomatoid fibrous histiocytoma: novel MR imaging findings

OBJECTIVE

To describe novel MR imaging features, and clinical characteristics of soft tissue angiomatoid fibrous histiocytoma (AFH) at presentation, local recurrence, and metastases.

MATERIALS AND METHODS

We described the MRI findings of six cases of histologically proven AFH. Pathologic findings, clinical presentation, and outcome were reviewed.

RESULTS

Lesions were primarily cystic. At initial presentation, tumors were surrounded by low signal intensity fibrous pseudocapsule. High signal intensity consistent with the lymphoplasmacytic infiltrate was seen in T2-weighted and post-contrast images as a rim over the hypointense pseudocapsule (double rim sign). High signal intensity infiltrating tumoral cords extended into adjacent tissues, through pseudocapsular defects on T2-weighted and post-contrast images. The cystic component and tumor cell nodularity were demonstrated at post-contrast images. Clinically, lesions were often thought to be benign, underwent marginal resection, developed local recurrence, and one developed second recurrence consisting of metastases. Recurrent tumors appeared as multiple masses, misinterpreted as post-surgical changes. An intramuscular recurrence demonstrated double rim and infiltrating margin.

CONCLUSIONS

A predominantly well-circumscribed, primarily cystic mass with double-rim and marginal infiltration on MRI suggests the possibility of AFH, in particular in child or young adult. Inclusion of these novel observations in AFH differential diagnosis may have a significant impact on treatment and prevention of recurrence.