Cutaneous balloon cell dermatofibroma (fibrous histiocytoma)

Dermatofibroma (DF) or cutaneous fibrous histiocytoma is a common benign skin tumor that exhibits multiple, distinct histologic variants. Although clear cell DF has been described in the literature, balloon cell degeneration causing a clear cell DF phenotype has been not been reported to date. Herein, we describe the clinicopathologic findings of balloon cell DF arising on the heel of a 43-year-old man. Clinically, it presented as enlarging tan-white, ulcerated, firm 1.5 cm nodule, clinically suspected to be pyogenic granuloma. Excisional biopsy revealed a circumscribed fibrous tumor populated by mostly clear and spindle cells. A zonal arrangement separated the varied tumor cells where the most superficial, polypoid area showed large, clear polygonal balloon cells; the mid-dermal zone demonstrated a transition between balloon cells, epithelioid cells, and spindle cells; and the deep dermal zone had storiform arrangement of spindle cells, with the fascicles separated by coarse collagen bundles. A CD10+ > CD68+ > Factor XIIIa+ immunophenotype was identified with negative immunolabeling for S-100 protein, HMB-45, cytokeratin AE1/AE3, desmin, smooth muscle actin, lysozyme, and leukocyte common antigen (LCA). Ultrastructurally, the clear tumor cells were filled with multiple, empty, nonmembrane bound vacuoles of varying size. No recurrence has been described after complete excision and 7 months of follow up. DF with balloon cell change, likely secondary to persistent irritation, should be added to the differential diagnosis of cutaneous primary and metastatic neoplasms showing balloon cell degeneration such as balloon cell melanocytic nevi and renal cell carcinoma, respectively.     

深部良性纤维组织细胞瘤一例

深部"良性"纤维组织细胞瘤是一种罕见的纤维组织细胞肿瘤,好发于四肢,本文报道1例.患者,女,56岁,左前臂无痛性皮下肿物4年,组织病理示境界清楚的单发性圆形皮下肿物,约1.8 cm×1.3 cm×0.6 cm,周围有纤维性假包膜,肿瘤细胞丰富,呈梭形或类圆形,编织状致密排列,细胞无明显异型性.免疫组化:CD34(+),...     

动脉瘤样纤维组织细胞瘤一例

患者,女,71岁。左胫前黑褐色结节5年。结合临床症状和组织病理检查,诊断为动脉瘤样纤维组织细胞瘤。给予手术完整切除治疗,随访至今未复发。     

Extra-abdominal subcutaneous metastasis of a gastrointestinal stromal tumor: report of a case and a review of the literature

Gastrointestinal stromal tumors (GISTs) metastasize primarily within the peritoneal cavity and to the liver. Superficial soft tissue metastases occur in about 1% of advanced GIST and are mostly associated with abdominal laparotomy scars and advanced disease. Extra-abdominal subcutaneous metastases of GIST have not been previously reported. Subcutaneous spindle cell tumors constitute a diagnostic challenge of which the differential diagnostic list can be limited by recognition of morphological, immunohistochemical en molecular genetic patterns. A 69-year-old woman presented with a fast growing subcutaneous nodule on her right upper arm. She was known with an imatinib-resistant advanced GIST, treated with sunitinib. The nodule was excised. Histopathological examination revealed a sharply demarcated tumor nodule in the subcutaneous fat with slightly spindled tumor cells, with pleomorphic nuclei and multiple mitoses. There was a hemangiopericytomatous vascular pattern. The cells stained positive for CD117 (KIT) and CD34. No KIT or platelet-derived growth factor receptor-α mutations were detected. We report the first case of an extra-abdominal subcutaneous metastasis of GIST. Although rare, metastatic GIST should therefore be included in the differential diagnosis of subcutaneous spindle cell tumors. A comparative survey of the histological, immunohistochemical and molecular genetic features of spindle cell tumors of the subcutis and a review of the literature is presented.     

Dermatofibrosarcoma Protuberans

An ultrastructural study of five cases of dermatofibrosarcoma protuberans revealed that the basic cell was a spindle shaped fibroblast with a peculiar deeply lobulated nucleus. An origin from perineural and endoneural cells could not be established since basal lamina material was sparsely present in only one case and other differential features were missing. In one case histiocytic cells were found, but also in this case the basic cell was the fibroblast; so evidence of relationship with fibrous histiocytoma was not found.     

皮肤纤维肉瘤

患者女,37岁。因左前臂皮下结节、溃疡伴痛痒6月余来诊。经抗生素系统及局部治疗效果不明显,皮损渐大,从未消退,近1个月溃疡范围明显增大。皮肤科检查：左前臂伸侧近肘关节处可见约5.5 cm × 4.0 cm大小浸润性斑块,表面溃疡形成,伴少许污秽分泌物;皮损境界尚清,质地较硬。皮损组织病理检查：表皮基底层色素增多,瘤组织紧贴表皮,真皮全层及皮下脂肪见多数大小不一的梭形细胞浸润,部分细胞明显异形,核分裂象易见,细胞之间有细小胶原纤维束。免疫组化：黑素瘤相关抗原、细胞角蛋白、HCK、Melan-a、S-100、平滑肌肌动蛋白、CD34、CD68均阴性,纤维连接蛋白（++）。组织病理诊断：纤维肉瘤,Ⅱ级。本病需与隆突性皮肤纤维肉瘤、皮肤梭形鳞状细胞癌、非典型纤维黄瘤、恶性纤维组织肉瘤等鉴别。     

Unusual presentation of multiple epithelioid cell histiocytomas

Epithelioid cell histiocytoma (ECH) is a variant of dermatofibroma that presents typically as a solitary nodule. We report a case of a 20-year-old male who presented with a bleeding nodular lesion on the left arm followed a month later by a nodule on the right nostril. Both lesions had epithelioid cells in the dermis, with focal Factor 13a and CD68 immunoreactivity. The left arm lesion, in addition, showed staghorn vasculature as well. Both lesions were interpreted as ECH. The patient had an unremarkable medical history. To the best of our knowledge, multiple ECHs have not been reported in the literature. An appropriate diagnosis of ECH is important as the differential diagnosis usually includes melanocytic lesions.     

Aneurysmal (angiomatoid) fibrous histiocytoma

We report a patient with aneurysmal (angiomatoid) fibrous histiocytoma manifested clinically as a single firm subcutaneous nodule, diagnosed as an epithelial cyst. Histologically, the growth showed massive histiocytic proliferation and areas with a vascular component. The lesion was histologically mistaken for Kaposi's sarcoma.     

Compound clear cell sarcoma misdiagnosed as a Spitz nevus

Clear cell sarcoma (CCS) typically presents as a tumor in the deep soft tissue of extremities, but when centered in the dermis it may be confused with a melanocytic nevus, primary nodular or metastatic melanoma. Compound variants of CCS, i.e. tumor cells present in both the epidermis and underlying soft tissue have not yet been described. Herein we report such a case, which initially presented as a nodule on the left wrist of a young woman at 19 years of age. The lesion was then interpreted as ‘Spitz nevus, compound type’. Twelve years later the patient noticed an enlarged lymph node in the right axilla. The excised lymph node was nearly completely replaced by malignant tumor cells, which were immunoreactive for S100 protein. They resembled the tumor cells of the wrist lesion. Cytogenetic analysis of the metastatic tumor revealed a t(12;22) translocation. Fluorescence in situ hybridization confirmed Ewing's sarcoma breakpoint region 1 (EWSR1) rearrangement in 70% of the tumor cells, thereby supporting the diagnosis of metastatic CCS. Our case is of interest because it documents that CCS can involve the epidermis. This observation expands the morphological spectrum associated with this tumor.     

Clear cell atypical fibroxanthoma:a clinicopathologic study

INTRODUCTION: The atypical fibroxanthoma (AFX) is considered by most authorities to represent a superficial or minimally invasive variant of malignant fibrous histiocytoma that most often presents as a solitary nodule on the sun-exposed skin of the elderly. Among the rarest variants is the clear cell AFX, a lesion which raises consideration to a differential diagnosis encompassing a variety of neoplastic and non-neoplastic clear cell proliferations. METHODS: We describe three cases of a distinctive cutaneous neoplasm arising in the sun-exposed skin of elderly patients. In all cases, formalin-fixed, paraffin-embedded tissue was available for analysis. The histology in concert with the immunophenotype was held to be diagnostic of the clear cell variant of AFX. RESULTS: All tumors comprised sheets of large cells with foamy cytoplasms and hyperchromatic, polyploid nuclei manifesting frequent and atypical mitoses. The critical cells in our cases expressed CD68 but none of CD3, CD20, CD34, S-100 protein, muscle-specific actin, factor XIIIa, Melan-A, carcinoembryonic antigen, or cytokeratin. CONCLUSION: Although typical examples of AFX provoke diagnostic consideration of spindle cell cancers of the skin (most often spindle cell melanoma, spindle cell squamous cell carcinoma, and leiomyosarcoma), the clear cell variant raises other differential diagnostic considerations instead. These include balloon cell melanoma, sebaceous carcinoma, pleomorphic liposarcoma, chordoma, parachordoma, tricholemmal carcinoma and clear cell squamous cell carcinoma. A diagnosis of AFX is one of exclusion; one must employ immunohistochemical markers to rule out the aforementioned differential diagnostic considerations. By reporting the fifth, sixth and seventh cases of clear cell AFX, we hope to alert dermatopathologists to this distinctive and unusual neoplasm, recognition of which is essential to avoid under- or over-diagnosis and inappropriate therapy.     

Benign cellular fibrous histiocytoma with erosion of the phalanx

Fibrohistiocytic tumors are characterized by the presence of fibroblast like spindle cells and histiocytes. The benign fibrous histiocytoma (dermatofibroma, BFH) as well as the malignant dermatofibrosarcoma protuberans (DFSP) and the malignant fibrous histiocytoma (MFH) belong to this group. A recurrent painful, hard 2 cm tumor on the left hallux of a 54-year-old woman led to an erosion of the underlying phalanx. The patient had suffered from ingrown toenails for more than 10 years. Histologically there was a deep penetrating fibrohistiocytic tumor that grew in a storiform pattern with interspersed foam cells. The tumor was CD34 negative and mitoses were scarce. The diagnosis was benign cellular fibrous histiocytoma (BZFH). BZFH belong to the group of BFH with a high recurrence rate especially after incomplete removal. Damage to the underlying bone has not been reported so far.     

Aneurysmal Benign Fibrous Histiocytoma with Atrophic Features

Aneurysmal benign fibrous histiocytoma is an uncommon pathologic variant of dermatofibroma. In addition to the features of a typical dermatofibroma, it has large cleft-like or cavernous blood-filled spaces with numerous hemosiderin pigments. It should be differentiated from angiomatoid malignant fibrous histiocytoma, malignant melanoma, and vascular tumors such as Kaposi''s sarcoma and angiosarcoma. Atrophic dermatofibroma is also a rare variant of dermatofibroma, and the combination of aneurysmal and atrophic features is rarer still. We report a case of aneurysmal benign fibrous histiocytoma with atrophic features in a 27-year-old male who had a grayish-brown atrophic patchy lesion on his back for 2 years.     

硬皮病样皮肤转移性恶性纤维组织细胞瘤1例

报告1例硬皮病样皮肤转移性恶性纤维组织细胞瘤。患者男,60岁。面颊及颈部皮肤硬韧1个半月。病理检查示:真皮浅中层胶原纤维间见散在或密集的类似成纤维细胞样细胞、组织细胞样细胞浸润,细胞核大而深染,呈长梭形及圆形,小血管腔内也见核大深染的细胞及多核巨细胞。免疫组化示:CD68(+),CD34,CK,SMA均阴性。诊断:皮肤转移性恶性纤维组织细胞瘤。     

Epithelioid cell histiocytoma with underlying artery damage

Although epithelioid cell histiocytoma is considered a variant of fibrous histiocytoma (dermatofibroma), the histogenesis of this condition remains controversial. A recent investigation suggested the possibility that epithelioid cell histiocytoma is an angioformative fibrous histiocytoma. We report a case of epithelioid cell histiocytoma underlying a damaged artery. This epithelioid cell histiocytoma with a central area of hemorrhage was associated with a medium-sized artery in the reticular dermis running vertically up to the lesion. Both the artery in the reticular dermis and its centrally branched artery in the subcutaneous tissue showed mural injury and intraluminal epithelioid endothelial proliferation. Immunohistochemically, the labeling rate for each of the antibodies studied in the epithlioid cells was as follows: 40% for Factor XIIIa, 5% for CD34, 20% for factor VIII-related antigen, and 10% for alpha-smooth muscle cell actin. This case may support the view that epithelioid cell histiocytoma is a vascular and angioformative fibrous histiocytoma.     

进行性结节性组织细胞瘤

目的描述进行性结节性组织细胞瘤临床、细胞结构及亚细胞结构的特征。方法 活检组织HE染色、免疫组织化学染色显微镜观察及电镜观察。结果镜下可见活检皮损与周围组织界限清晰,并见多核巨细胞、泡沫样组织细胞和组织细胞,部分区域可见席纹状排列梭形细胞,多核巨细胞、梭形细胞、泡沫样组织细胞、组织细胞CD68、溶酶体标志物染色阳性,S-100蛋白染色阴性。冰冻组织切片苏丹黑染色可见泡沫样组织细胞内脂滴。电镜下未发现Birbeck颗粒和Caputo小体。结论本病应与多发性幼年性黄色肉芽肿、网状组织细胞增生症、发疹性组织细胞瘤、播散性黄瘤病鉴别,该病例可以确立进行性结节性组织细胞瘤诊断。     

额面部丛状神经鞘瘤1例

报告额面部丛状神经鞘瘤1例。患者女,48岁,因“额面部左侧肿物17年,左眉弓皮下肿物3年”就诊。皮肤专科检查：额面部左侧见一约8 mm×6 mm×3 mm大小黄红色类圆形结节,隆起于皮面,表面光滑,质地韧,无压痛。左眉弓上方皮下扪及一约9 mm×8 mm×4 mm大小的结节,质地韧,轻度压痛,活动度可。两处皮损组织病理均为：真皮中下层内可见多个由梭形细胞组成的肿瘤团块,呈结节状,结节间被透明疏松的纤维结缔组织所分隔。免疫组化结果：S-100(+++),Vimentin(+),SMA(-),CD34(-),Ki-67(5%+)。诊断为丛状神经鞘瘤。予以手术切除,随访3年未复发。     

Marked response to imatinib mesylate in metastatic acral lentiginous melanoma on the thumb

We report a case of melanoma that had a marked response to treatment with imatinib mesylate (IM). The patient was a 61‐year‐old man who presented with a small red nodule on the thumb and destruction of the nail plate. On histological examination, this lesion was diagnosed as a melanoma, and computed tomography revealed lymph‐node swelling in the left axilla and nodules in both lung fields. Although the patient received intratumoral injections of interferon‐β and systemic administration of dacarbazine, both primary and metastatic lesions increased in size. Immunochemistry detected a KIT mutation, which was confirmed by DNA sequencing analysis, and patient was given IM. Within 2 weeks of starting the IM regimen, the size of the nodule on the nail plate markedly decreased, and the axillary lymph‐node swelling and lung‐nodule formation regressed. This case suggests that IM may be a promising treatment option for KIT mutation‐positive melanoma.     

Malignant fibrous histiocytoma of the skin with marked inflammatory infiltrate: a sarcoma mimicking malignant lymphoma

Three cases of malignant fibrous histiocytoma of the skin with a marked inflammatory infiltrate in the stroma are reported. The inflammatory infiltrate, composed mainly of T-lymphocytes, obscured the nature of the neoplasms, and immunohistochemical studies were required to establish the diagnosis. Two tumors arose in the sun-damaged skin of the face, and one tumor arose in the chest wall. One patient developed a local recurrence with histopathologic findings similar to those observed in the original lesion, including the inflammatory infiltrate. Possible differential diagnoses include large cell lymphoma, inflammatory pseudotumor, inflammatory leiomyosarcoma, and spindle cell squamous cell carcinoma. The presumed rarity of inflammatory changes in malignant fibrous histiocytoma of the skin is supported by the absence of reported cases.     

Atypical fibrous histiocytoma of the skin with CD30 and p80/ALK1 positivity and ALK gene rearrangement

We report the case of a two patients who presented with a solitary, asymptomatic, angiomatoid nodule on the right thigh. Histopathological finding showed a poorly circumscribed lesion, located in the dermis. The morphological aspect strongly suggested the diagnosis of atypical fibrous histiocytoma (AFH), but surprisingly, the neoplastic cells were diffusely CD30+, with a membrane staining devoid of paranuclear dot. The lesions were tested for p80/ALK1 expression. Surprisingly, we found a diffuse cytoplasmic positivity. Interestingly, using break‐apart fluorescent in situ hybridization (FISH), we evidenced an ALK rearrangement in nearly 50% of the neoplastic cells. The expression of CD30 and ALK1 with ALK gene rearrangement raised the possibility of three diagnoses: a primary cutaneous anaplastic large cell lymphoma (ALCL), a cutaneous inflammatory myofibroblastic tumor (IMT), an AFH of the skin associated with ALK gene rearrangement and CD30 positivity. The three hypotheses were discussed and finally, although p80/ALK1 expression and cytogenetic abnormalities in fibrous histiocytoma (FH) are not yet reported to the best of our knowledge, we favored the diagnosis of AFH.     

A Case of Subcutaneous Malignant Fibrous Histiocytoma Circumscribed by Fibrous Tissue

We report a case of malignant fibrous histiocytoma (MFH) located in the subcutaneous tissue on the right axilla. We excised the tumor sufficiently beyond the clinical margin. It was pathologically diagnosed as a storiform-pleomorphic type of malignant fibrous histiocytoma almost completely circumscribed by fibrous tissue, including fascicles of fibroblasts; this is a rare histological picture. The tumor has not recurred for three years. Although MFH frequently undergoes metastasis, the circumscribed-type subcutaneous MFH characteristic of superficiality and of histologically well-defined structure seems to have a relatively more favorable prognosis after adequate radical excision.