Atypical fibroxanthoma

Atypical fibroxanthoma (AFX) is a rare neoplastic disease of the skin. Since the term was coined in the early 1960s, the disease has been viewed in many ways. For a long time AFX was regarded as a superficial variant of malignant fibrous histiocytoma (MFH). When the concept of MFH was re‐evaluated and the term “undifferentiated pleomorphic sarcoma” (UPS) introduced, the controversy about the nature of AFX increased. The following review aims at providing an understanding of the present status of diagnosis and therapy of AFX based on the historical context and current data.     

Atypical fibroxanthoma

Atypical fibroxanthoma (AFX) is a rare neoplastic disease of the skin. Since the term was coined in the early 1960s, the disease has been viewed in many ways. For a long time AFX was regarded as a superficial variant of malignant fibrous histiocytoma (MFH). When the concept of MFH was re-evaluated and the term "undifferentiated pleomorphic sarcoma" (UPS) introduced, the controversy about the nature of AFX increased. The following review aims at providing an understanding of the present status of diagnosis and therapy of AFX based on the historical context and current data.     

Atypical fibroxanthoma with prominent sclerosis

BACKGROUND: Malignant cutaneous spindle cell lesions with marked sclerosis are uncommon. Only a few cases of cutaneous leiomyosarcoma and dermatofibrosarcoma protuberans with sclerosis have been published. METHODS: We report a case of atypical fibroxanthoma (AFX) with prominent sclerosis and hyalinization occurring on the scalp of an 81-year-old male. RESULTS: Histopathologic examination revealed an exophytic, well-delineated, focally ulcerated tumor arising in sun-damaged skin. The lesion was composed of atypical spindle cells arranged in a fascicled and vaguely storiform pattern. Occasional multinucleated giant cells were present. The tumor cells were strongly positive for CD99 (O13), vimentin, and smooth muscle actin, and focally positive for CD68. There was striking sclerosis with hyalinization throughout the lesion. CONCLUSIONS: Rarely, AFX may exhibit marked sclerosis with areas of complete replacement of tumor by hyalinized collagen. In a small biopsy, such hyalinization may be a diagnostic pitfall leading to an erroneous diagnosis.     

皮肤非典型性纤维黄色瘤

自Helwig(1963)首先命名本病以来,近年来已引起国内外的高度重视(1-8).本病形态上具有高度恶性的组织象,但其临床生物学行为往往为良性.少数病例术后易复发,转移病例甚少(4-6)鉴于本病国内报道很少,兹将我院所见3例报告于下.     

Atypical fibroxanthoma with dermal amyloid deposit

Atypical fibroxanthoma (AFX) has been associated with several secondary changes, such as keloidal areas, myxoid or chondroid changes, osteoclast-like giant cells, sclerosis, fibrosis, pigmentation, hyalinization, or hemorrhagic areas. We report a case of an AFX 4 cm in diameter on the forehead of a 77-year-old male patient. There were dermal amyloid deposits intermingled with the tumor fascicles on the periphery of the lesion. A moderate inflammatory chronic lymphoplasmacytic infiltrate was found in the periphery of the tumor. The amyloid deposits were positive with Congo red staining (but negative after permanganate-treatment). The deposit was also immunostained with antibodies against CKs (AE1/AE3 and CK5/6). It did not stain with anti-amyloid A, or with antibodies against either kappa light or lambda light chains. Therefore the amyloid deposit was keratinic in nature.     

Atypical fibroxanthoma of the skin

A typical fibroxanthoma is a solitary tumour of the skin, which occurs mostly on sun-exposed areas in elderly people. The diagnosis can only be made with certainty on the typical histological findings, which suggest a bizarre malignant tumour. Although metastasizing tumours are reported in the literature, the authors believe that the true atypical fibroxanthoma is benign. Correct diagnosis obviates the need for unnecessary radical surgery. The possibility of atypical fibroxanthoma should always be considered when a histologically bizarre tumour is found on sun-damaged or irradiation-damaged skin in elderly patients or on previously traumatized sites. In this paper five cases are added to the 346 cases culled from the literature. Electron microscopic investigations in one case demonstrated cells with delicate cytoplasmic fibrils in small bundles. This does not necessarily suggest filaments of myofibroblasts, as has been previously reported.     

Atypical fibroxanthoma in a patient with xeroderma pigmentosum

A 3-year-old boy with xeroderma pigmentosum developed a papule on the right ala nasi that had the light-microscopic, immunohistochemical, and ultrastructural features of atypical fibroxanthoma. This lesion most commonly arises on the sun-exposed skin of older adults. The occurrence of an atypical fibroxanthoma in such a patient adds weight to the concept that this tumor of "fibrohistiocytic" origin is induced by ultraviolet exposure. Mechanisms of tumor formation in a patient with xeroderma pigmentosum may be similar to those occurring in the more typical situation in adults.     

Atypical fibroxanthoma in tuberous sclerosis

Atypical fibroxanthoma is not an uncommon condition occurring in elderly on the sun exposed areas. We report a case of atypical fibroxanthoma in a patient with tuberous sclerosis. The lesion was excised surgically. There was no evidence of any metastasis.     

Atypical fibroxanthoma on a bald scalp

We present the clinical, histopathological and immunohistochemical findings of an atypical fibroxanthoma (AFX) on the bald scalp of an 81-year-old French man who had worked at a private high school in Japan as a janitor for over 40 years. The patient had a history of basal cell carcinoma on the nape, and chronic solar radiation seemed to be a predisposing factor in the pathogenesis of this association. This case showed the typical clinical and histopathological characteristics of AFX, and the immunohistochemical results suggested differentiation of histiocytes and myofibroblasts. The AFX was completely resected, and the patient has not had tumor recurrence or metastasis for over four postoperative years. This case therefore provides further support to the theory that AFX displays a clinically benign course, even though it is essentially a malignant tumor histologically located in the dermis. Therefore, we must excise AFX completely with great care and perform regular physical examinations for several years after operation.     

Atypical fibroxanthoma in an HIV-infected individual

Atypical fibroxanthoma is a neoplasm primarily occurring in older patients, with a predilection for photo-damaged skin of the head and neck. Compared to the immunocompetent population, patients infected with HIV have a higher risk of certain malignancies including non-Hodgkin lymphoma, Kaposi's sarcoma and skin cancer. Although atypical fibroxanthoma has been reported in another immunocompromised group, namely organ transplant recipients, there are no previous reports in the published literature of this tumour arising in patients infected with HIV. We report a case of an atypical fibroxanthoma arising in a 71- year old HIV-positive male.     

Atypical fibroxanthoma/malignant fibrous histiocytoma

ABSTRACT: Atypical fibroxanthoma (AFX) is an unusual spindle cell tumor occurring on actinically damaged skin of the head and neck. Clinically, it is often confused with basal cell carcinoma, squamous cell carcinoma, or even melanoma. Although initially thought to be a diagnosis of exclusion histologically, newer immunostains have helped in the identification of AFX. Mohs micrographic surgery has been utilized for the treatment due to its tissue sparing ability along with lower recurrence rate.     

Atypical fibroxanthoma: two unusual variants

Two unusual fibroxanthomas were studied by light microscopy. The first case contained numerous osteoclast-like cells and resembled malignant giant cell tumour of soft tissues, a variant of malignant fibrous histiocytoma. Osteoclast-like giant cells were negative for lysozyme and alpha-1-antitrypsin. The second case contained areas of chondroid differentiation which resembled chondrosarcoma. Tumour cells within the cartilaginous areas were positive for S100 protein.     

Atypical fibroxanthoma. A study with antibody to S-100 protein

Fourteen biopsy specimens from ten patients with atypical fibroxanthoma were studied with the peroxidase-antiperoxidase method for binding of S-100 antibody. Six specimens from four patients were minimally positive. The S-100-positive cells were observed in greatest concentrations at the periphery of the lesions and were associated with perivascular inflammatory cells. By this method, it appears that there is not a Langerhans' cell type of atypical fibroxanthoma. The S-100 antibody can help differentiate desmoplastic juvenile melanoma and malignant melanoma from atypical fibroxanthoma.     

Atypical fibroxanthoma: a series of 25 cases

Objective Atypical fibroxanthoma is a rare mesenchymal tumour of skin that develops on skin of elderly patients. We analysed our patients with atypical fibroxanthoma over the last 8 years. Patients and methods We analysed the pathology files of our hospital for the period 2001–2009. In all cases, histology and immunohistology were performed. Data on co‐morbidities, treatment and outcome were obtained. Results We identified 25 patients (except two female patients, the rest were men) aged 52–95 years (mean: 79.5 years; standard deviation ± 9.06 years). All tumours were localized in the head and neck region, except a single tumour on the shoulder. Fourteen patients had a cancer history, six had actinic keratoses or Bowen’s disease (n = 1). Five patients had cardiac surgery or pacemaker, one each had a renal transplant, systemic sarcoidosis or non‐Hodgkin’s lymphoma. Medical history was positive for radiotherapy or chemotherapy in four patients. Histology showed a spindle‐shaped dermal and subcutaneous tumour growth intermingled with multinucleated giant cells. The phenotype of tumour cells was vimentin‐positive, but S100‐ and keratin‐negative. Some tumours showed a focal expression of CD68. Complete microhistographic controlled surgery (‘Mohs like’) was possible in all cases followed by mesh‐graft transplantation in three patients. Eighteen patients showed a complete remission. Four patients had a relapse within 2 years of follow‐up treated by surgery. One patient is still under radiotherapy. All patients with a safety margin of 2 cm had no recurrence or relapse during follow‐up. Conclusions Micrographic controlled surgery with wide 2 cm safety margins is the treatment of choice. A regular follow‐up for the next 5 years is recommended.