巨细胞纤维母细胞瘤的临床与病理学观察

目的：研究巨细胞纤维母细胞瘤的临床病理学特点和免疫组织化学表型,探讨其鉴别诊断及组织学起源。方法：采用光镜观察结合免疫组织化学LSAB法标记对7例巨细胞纤维母细胞瘤进行分析。结果：7例患者中6例为儿童,1例为35岁成年人。男性5例,女性2例。临床上主要表现为躯干和四肢皮下缓慢增大的无痛性结节,平均直径2．9cm。镜下显示,肿瘤境界不清,主要位于真皮层。瘤细胞主要由轻至中度异型的梭形细胞组成,多呈疏松的束状或波浪状排列,间质呈纤维黏液样,部分区域呈致密胶原化。本病的特征性形态表现肿瘤内含有一些不规则分布的裂隙样或扩张窦样的假脉管性腔隙,其腔隙面内衬一层不连续的梭形细胞和核深染多核巨细胞,两种细胞在形态上有移行。免疫组织化学标记显示梭形细胞和多核巨细胞均表达波形蛋白和CD34.5 附有随访资料,其中2例术后复发。结论：（1）巨细胞纤维母细胞瘤是一种好发于儿童的中间性纤维母细胞性肿瘤,较易局部复发,掌握其独特的临床病理学特征对避免误诊为一些具有相似形态的病变具有重要意义;（2）巨细胞纤维母细胞瘤与好发于成人的隆突性皮纤维肉瘤的在临床表现、免疫组织化学、细胞及分子遗传学上均极为相似,在组织上也可共存,提示两者在组织学发生了关系密切,可能同属CD34阳性树突状纤维母细胞肿瘤一族。     

Genomic gains of COL1A1-PDFGB occur in the histologic evolution of giant cell fibroblastoma into dermatofibrosarcoma protuberans

Giant cell fibroblastoma (GCF) is a subcutaneous mesenchymal neoplasm characterized by the chromosomal t(17;22), which results in the formation of the fusion gene COL1A1-PDGFB. This same fusion gene is also seen in the supernumerary ring chromosome of dermatofibrosarcoma protuberans (DFSP). Several studies have addressed the molecular genetics of DFSP but molecular cytogenetic characterization of individual areas and cell components in pure GCF and GCF/DFSP hybrids have not been performed. Herein, we studied the frequency and genomic copy number of COL1A1-PDGFB in pure GCF and GCF/DFSP hybrids, and identified the molecular cytogenetic signatures in individual cells in each component. Four pure GCF and nine GCF/DFSP hybrids were studied. All tumors exhibited classical histological features and CD34 expression. COL1A1 and PDGFB rearrangements were evaluated by fluorescence in situ hybridization (FISH) using probes for COL1A1 and PDGFB on paraffin-embedded thin tissue sections. All GCF and GCF/DFSP hybrids showed unbalanced rearrangements of COL1A1-PDGFB at the molecular cytogenetic level. Genomic gains of COL1A1-PDGFB were found predominantly in the DFSP component of GCF/DFSP hybrids but in none of the pure GCF, suggesting that these gains are associated with the histologic evolution of GCF into DFSP. The molecular cytogenetic abnormalities were found not only in the spindle/stellated cells but also in individual nuclei of the multinucleated giant cells, suggesting that these cells may result from the fusion of individual neoplastic cells.     

Palisading and verocay body-prominent dermatofibrosarcoma protuberans: a report of three cases

The aim of this report is to draw attention to nuclear palisading and Verocay body formation as peculiar, previously undescribed histological findings in rare instances of dermatofibrosarcoma protuberans (DFSP). METHODS AND RESULTS: Three indurated, nodular or plaque skin lesions were diagnosed as DFSP on the basis of their storiform proliferation of spindle-shaped cells diffusely infiltrating the dermis and subcutaneous tissue. Sclerosing and giant cell areas were also identified. Unexpectedly, conspicuous nuclear palisading was also noted in all cases and Verocay body formation was present in two. Immunostains were positive for CD34 and negative for S100 protein in every instance. Proliferating cells were seen to display fibroblast-like features by ultrastructural study of one case. CONCLUSIONS: DFSP may rarely show a schwannoid histological appearance as the result of nuclear palisading and even Verocay body formation. In this setting, both the search for DFSP characteristic morphologic features and the performance of CD34 and S100 protein immunohistochemistry will facilitate the correct diagnosis.     

Transformed dermatofibrosarcoma protuberans: a clinicopathological study of eight cases

BACKGROUND: Fibrosarcomatous (FS) or malignant fibrous histiocytomatous (MFH) transformation of dermatofibrosarcoma protuberans (DFSP) is a rare, but well known, entity. DFSPs with sarcomatous areas have questionable biological behaviour. Several studies suggest that they have a higher risk for local recurrence and distant metastases than ordinary DFSPs. One recent study described no difference in the behaviour of conventional and transformed DFSP. AIMS: To investigate the biological behaviour of a series of transformed DFSPs. METHODS: Eight transformed DFSPs were analysed clinicopathologically. Follow up ranged from four to 36 years. RESULTS: The tumours involved the trunk (six cases) and lower extremity (two cases) and measured 3.5-8 cm (median, 4). Sarcomatous change presented de novo in all cases. The type of sarcomatous change was FS (five cases) and MFH (three cases). The estimated proportion of sarcomatous area in the tumour was 25-70% (median, 43.37%). Mitotic counts ranged from nine to 16 mitotic figures/10 high power fields in the FS and MFH areas (median, 12), and from one to three in the DFSP areas. Six patients were treated by wide local excision with histopathologically negative margins and two were treated by simple surgical excision with positive margins. Three patients developed recurrences and one developed metastasis during follow up. Of those treated by wide local excision, one developed recurrence. All tumours expressed CD34 in the DFSP component, but only three in the sarcomatous area. CONCLUSIONS: Although DFSP containing sarcoma may be a more aggressive tumour, its behaviour can be influenced by surgical treatment.     

FNA diagnosis of giant cell fibroblastoma: A case report of an unusual pediatric soft tissue tumor

Giant cell fibroblastoma (GCF) is a rare pediatric soft tissue tumor, which exists on a spectrum with dermatofibrosarcoma protuberans (DFSP). Histologic features are well established for these entities; however, cytologic findings have not been well characterized. We report for the first time a case of GCF, confirmed by cytogenetics, with mixed DFSP features. In this case of an 8‐month‐old boy, a fine needle aspiration specimen showed a low‐grade spindle cell tumor, with oval to spindled cells dispersed singly and in patternless groups, and with occasional giant cells. Subsequent histologic features were consistent with GCF, which is an uncommon, CD34 positive, soft tissue neoplasm with a distinct molecular aberration. This case emphasizes the differential diagnosis in pediatric soft tissue tumors and stresses the unique features of GCF. Diagn. Cytopathol. 2015;43:325–328. © 2014 Wiley Periodicals, Inc.     

Sarcomatous dermatofibrosarcoma protuberans metastasized to the lung: Preservation of CD34 expression in tumor cells

A case of metastatic dermatofibrosarcoma protuberans (DFSP) In a 47-year-old woman is presented. Dermatofibrosarcoma protuberans occasionally recurs, but rarely metastasizes. The patient underwent local removal of the nuchal tumor by a general practitioner, followed by a rapid recurrence. She underwent total removal of the tumor and a diagnosis of spindle cell sarcoma was made after an Incisional biopsy was performed. This lesion had both a typical DFSP-like area and a flbrosarcoma (FS)-like area. After 7 years, an abnormal lung shadow was observed and a segmental lung redon was petformed. Histologically, the lung tumor was similar to the FS-like area in the nuchal tumor. Confirming CD34 expression in the tumor cells, this lung tumor was diagnosed as metastatic DFSP. Usually CD34 expression is unique to DFSP but almost negative in FS-like areas. In the present case, the FS-llke area in the nuchal tumor showed decreased CD34 reactivity, as previously reported, but the FS-like area In the metastatic tumor still widely preserved CD34 expression. The presented case suggests that the FS-like area in DFSP is histogenetically different from typical FS or malignant fibrous histiocytoma.     

Dermatofibrosarcoma protuberans with EMa+ cells. Report of a case suggesting perineurial cell differentiation

A case of dermatofibrosarcoma protuberans (DFSP) with epithelial membrane antigen (EMA)-positive cells is described. The tumor was excised from the left groin of a 28-year-old woman. It showed characteristic histologic features of DFSP with typical diffuse immunohistochemical positivity for CD34. Moreover, scattered neoplastic cells expressed EMA, suggesting perineural cell differentiation. Ultrastructural study found perineurial cell features, such as thin long bipolar cytoplasmic processes, pinocytotic vesicles, fragments of external lamina and/or external lamina-like material, attachment plaques, and desmosome-like junctions. This observation, together with previous immunohistochemical findings of EMA-positive cells in a subset of DFSPs, strongly suggests perineurial cell differentiation in these tumors. DFSP should be included in the differential diagnosis of EMA-positive spindle cell lesions of superficial soft tissue and skin.     

EMA+ cells in dermatofibrosarcoma protuberans. A study of 11 tumors suggesting perineurial cell differentiation

Expression of epithelial membrane antigen (EMA) was found in 11 of 57 (19%) cases of dermatofibrosarcoma protuberans (DFSP). These tumors with EMA+ cells showed the following histological features: classical storiform pattern in all 11 cases, myxoid areas in three cases, Bednar tumor pattern in one case, and fibrosarcoma-like areas in one case. The EMA+ cells had a tendency to occur in moderately cellular and collagen-rich areas with parallel cell arrangement (4 cases) and in perivascular areas (3 cases). In such parts, a nuclear palisading and a wavy appearance of the nuclei were seen focally. One tumor contained perineurioma-like areas with whorled cell arrangement and EMA+ cells. The EMA+ cells were also found in ordinary storiform areas (6 cases), but here they were isolated and scarce. In two cases, the EMA+ cells were juxtaneural; therefore their origin from a sheath of preexisting nerves can not be excluded. Expression of EMA may reflect true perineurial cell differentiation in DFSP, as suggested previously in several ultrastructural and cytogenetic studies. The knowledge of occasional EMA positivity in DFSP is needed for a differential diagnosis between DFSP and other EMA+ soft tissue lesions.     

Composite dermatofibrosarcoma protuberans-giant cell fibroblastoma recurring as Bednár tumor-giant cell fibroblastoma with mucoid lakes and with amputation neuroma

We report an unusual case of composite giant cell fibroblastoma-dermatofibrosarcoma protuberans (DFSP) that, in its second recurrence, contained a pattern of Bednár tumor (BT) and giant cell fibroblastoma (GCF). The recurrent tumor showed extreme myxoid change with creation of mucoid lakes, which mimicked a pattern of myxoid liposarcoma. One area in the recurrent lesion contained amputation neuroma overgrown with neoplastic spindle cells, which simulated a nerve sheath neoplasm. This case demonstrates common histogenesis of GCF, DFSP and BT, and it shows how broad morphological spectrum can be produced by a composite tumor, especially when the tumor includes unconventional growth pattern or additional non-neoplastic lesion.     

Giant Cell Fibroblastoma: A Case Report and lmmunohistochemical Comparison with Ten Cases of Dermatofibrosarcoma Protuberans

A 7 year old boy with giant cell fibroblastoma (GCF) of the skin and subcutaneous tissue of the right chest wall is described. To date, the histogenesis of GCF has not been clarified. The reason for the diversity of immunohistochemical data among various authors may be because the specimens studied were from only part of the lesion, or reduction of antigenicity through the preparation process. However, our findings based on studies of many specimens from various parts of the tumor for accurate immunohistochemical evaluation suggest that GCF may be a myofibro histiocytic tumor. Recently, the suggestion that GCF is a juvenile form of dermatofibrosarcoma protuberans (DFSP) has been reported. In addition to the present case, we performed immunohistochemical examination of 10cases of definitely diagnosed DFSP for comparison. The immunohistochemical characteristics of these two neoplasms were concordant. However, from clinical and morphological viewpoints, it seems premature to recognize GCF as a juvenile form of DFSP. Acta Pathol Jpn 41: 552–560, 1991.     

Composite tumor consisting of dermatofibrosarcoma protuberans and giant cell fibroblastoma associated with intratumoral endometriosis. Report of a case

We present a unique case of composite skin tumor of the vulva consisting of dermatofibrosarcoma protuberans (DFSP) and giant cell fibroblastoma (GCF) with an intratumoral focus of endometriosis. A 31-year-old female with a 10-year-history of a recurring subcutaneous tumor in the vulvar area underwent excision of the seventh recurrence of the tumor. Microscopic examination revealed a composite fibrohistiocytic tumor consisting of DFSP and GCF. Additionally, a focus of endometriosis within the tumor tissue was found. Malignant transformation of extragonadal endometriosis has already been described; we present, however, the occurrence of a focus of endometriosis within the tissue of a hormonally independent soft tissue tumor. There is a possible link to the occurrence of cutaneous endometriosis at previous surgery sites and in the scars. The presence of endometriosis within the soft tissue tumor represents, to the best of our knowledge, a previously undescribed collision phenomenon.     

Fine‐needle aspiration of dermatofibrosarcoma protuberans metastasizing to hemithorax with superior vena cava compression: Case report and literature review

Dermatofibrosarcoma protuberans (DFSP) is a low‐grade spindle cell tumor of the skin commonly arising on the trunk and extremities which tends to be slow growing yet locally aggressive. DFSPs are associated with a good prognosis when surgical excision with negative margins is achieved. Although local recurrences occur up to 50% of incompletely resected cases, distant metastases are very rare. Here, we report a case of DFSP metastasizing to the right hemithorax diagnosed by an endobronchial ultrasound‐guided fine‐needle aspiration (FNA) 9 years after initial presentation. The aspirate showed a bland spindle cell proliferation that was morphologically similar to the original skin excision; the storiform pattern was particularly prominent in tumor‐tissue fragments in the cellblock. Immunostaining showed strong, diffuse positivity for CD34. Molecular studies demonstrated a characteristic COL1A1/PDGFB fusion in both original and metastatic specimens. A review of the literature revealed that metastatic DFSP most often involves the lungs, occurs usually in cases with fibrosarcomatous transformation and after a local recurrence, and presents on average 4.5 years after the original diagnosis. This case did not show fibrosarcomatous transformation or local recurrence prior to metastasis 9 years later. In summary, it is important to consider the potential for metastases years after a nonrecurring primary DFSP, despite its rarity. Cytologic features when complemented by ancillary studies and awareness of the patient's prior clinical history permit a confident diagnosis of metastatic DFSP by FNA. In addition, by confirming the characteristic translocation, tyrosine‐kinase inhibitor imatinib can provide additional treatment options for unresectable metastatic DFSP.     

Tenascin differentiates dermatofibroma from dermatofibrosarcoma protuberans: comparison with CD34 and factor XIIIa

Differentiation of dermatofibroma (DF) from dermatofibrosarcoma protuberans (DFSP) can be difficult. CD34 and Factor XIIIa have been used to differentiate DF from DFSP. However, there is overlap and lack of specificity of their expression. Tenascin is an extracellular matrix glycoprotein that is involved in embryogenesis, carcinogenesis, and wound healing. The aim of the study was to assess the role of tenascin in DF and DFSP and compare the results with those obtained with CD34 and Factor XIIIa. Immunohistochemical staining was performed on 20 cases each of DFSP and DF, using antibodies to tenascin, CD34 and Factor XIIIa, and the streptavidin biotin technique. Positivity for all 3 antibodies was assessed within the tumors. Tenascin expression was also assessed at the dermal-epidermal junction. Strong tenascin positivity was noted at the dermal-epidermal junction overlying the lesion in 20 of 20 cases of DF (100%) and was negative over the lesion in 20 of 20 cases DFSP (100%). Tenascin was noted within the lesion of 80% of both DF and DFSP (16/20 cases). CD34 was strongly expressed in 16 of 20 (80%) DFSP and 5 of 20 (25%) DF, whereas Factor XIIIa was strongly expressed in 19 of 20 (95%) DF and 3 of 15 (15%) DFSP. Although CD34 was expressed in 80% DFSP and Factor XIIIa in 95% of DF, there was overlap in their expression in the 2 types of tumors. The increased expression of tenascin at the dermal-epidermal junction overlying the lesion in DF but not in DFSP, differentiated these 2 tumors. In contrast, tenascin expression within the lesion did not differentiate DF from DFSP.     

Giant cell fibroblastoma. A case report and immunohistochemical comparison with ten cases of dermatofibrosarcoma protuberans.

A 7-year-old boy with giant cell fibroblastoma (GCF) of the skin and subcutaneous tissue of the right chest wall is described. To date, the histogenesis of GCF has not been clarified. The reason for the diversity of immunohistochemical data among various authors may be because the specimens studied were from only part of the lesion, or reduction of antigenicity through the preparation process. However, our findings based on studies of many specimens from various parts of the tumor for accurate immunohistochemical evaluation suggest that GCF may be a myofibrohistiocytic tumor. Recently, the suggestion that GCF is a juvenile form of dermatofibrosarcoma protuberans (DFSP) has been reported. In addition to the present case, we performed immunohistochemical examination of 10 cases of definitely diagnosed DFSP for comparison. The immunohistochemical characteristics of these two neoplasms were concordant. However, from clinical and morphological viewpoints, it seems premature to recognize GCF as a juvenile form of DFSP.     

Spindle cell lipoma-like tumor, solitary fibrous tumor and myofibroblastoma of the breast: a clinico-pathological analysis of 13 cases in favor of a unifying histogenetic concept

We reviewed the clinico-pathological features of a series of 13 cases of benign spindle stromal tumors (BSSTs) of the breast relating to a basic common theme consisting of a well-circumscribed proliferation of vimentin+/CD34+/BCL-2+/CD99+ spindly to oval-epithelioid cells, variably arranged in haphazard to short fascicular growth pattern, with interspersed thick or thin collagen bands. Morphological variations included atypical mono- or multi-nucleated cells in five cases and a mature lipomatous tumor component, varying from focal to prominent, in eight cases. Based on morphological and immunophenotypical features, a distinction was made between two main subtypes of these tumors--fibroblastic and myofibroblastic. The former subtype included two cases respectively represented by a typical solitary fibrous tumor (SFT) and a neoplasm labeled "spindle-cell lipoma (SCL)-like tumor", closely reminiscent of soft tissue SCL. Both tumors had cells with fibroblastic-like appearance, haphazardly arranged and immunoreactive for vimentin, CD34, BCL-2, and CD99. The latter subtype, comprised nine cases exhibiting evidence of myofibroblastic differentiation (desmin and alpha-smooth muscle actin) which were classified as myofibroblastomas (MFBs). The remaining two cases were defined as "mixed BSSTs", having typical features of diverse neoplasms, respectively represented by a case of MFB with focal SFT and pleomorphic/SCL-like areas, and SFT with focal MFB-like component. The common basic morpho-immunophenotypical features, the possibility that both fibroblastic and myofibroblastic tumors may contain an additional mature lipomatous component, and the existence of hybrid stages (mixed BSSTs) strongly support the view that such tumors belong to the same category of lesions. We postulate that the precursor of all these neoplasms is the vimentin+/CD34+ cells of the mammary stroma, the well-known inherent plasticity of which to differentiate toward several mesenchymal lines, provides the explanation for the phenotypic heterogeneity of these neoplasms. Accordingly, the encompassing term "benign spindle stromal tumors of the breast" is advocated for such tumors.     

伴有肌样/肌纤维母细胞性分化的隆突性皮纤维肉瘤的临床病理分析

目的 探讨隆突性皮纤维肉瘤（ＤＦＳＰ）中肌样／肌纤维母细胞性分化的本质及其临床病理学意义。方法 采用常规ＨＥ切片对１２４例ＤＦＳＰ进行筛选,对6例伴有肌样／肌纤维母细胞性分化的ＤＦＳＰ病例进行免疫组织化学标记,其中２例加做电镜检测。结果 肌样／肌纤维母细胞性分化多出现在纤维肉瘤型ＤＦＳＰ（ＦＳ－ＤＦＳＰ）中,表现为肿瘤周边部或肿瘤内散在性分布的深嗜伊红色小结节或短要束,由梭形细胞组成,细胞多无异型性,核分裂象也罕见,形态上似平滑肌细胞或肌纤维母细胞。免疫组织化学标记显示肌样区域细胞表达α－平滑肌肌动蛋白和肌物质特异性肌动抗原,不表达ＣＤ３４;电镜观察证实细胞含有质膜下微丝束、局灶性致密体及微胸饮囊泡样结构,与肌纤维母细胞相一致,结论 ＤＦＳＰ中的肌样／肌纤维母细胞性分化可能是间质中肌纤维母细胞增生的结果,并非代表了瘤细胞的真性肌纤维母细胞性分化。     

Perineurial cell differentiation in neurofibromas. Report of eight cases including a case with composite perineurioma-neurofibroma features

Among 99 cases of neurofibroma (NF), eight tumors (8%) contained epithelial membrane antigen (EMA)-positive perineurial cells inside the lesions. These cells were numerous and represented a significant part of the tumor cell population. In case 7, EMA-positive cells represented approximately half of the tumor. These patients' ages ranged from 23 to 73 years (average 51 years). Six patients were females and two were males. Neurofibromatosis type 1 was present in one case. The histological types of neurofibromas with EMA-positive cells were as follows: cutaneous, well-circumscribed, localized type in four cases; cutaneous diffuse type in one case; subcutaneous, well-circumscribed type in two cases; and subcutaneous plexiform type in one case. Perineurial cell differentiation was suspected by examining routinely stained sections in four cases; it was unsuspected in four cases. The perineurial cells were arranged in a pattern similar to that of "pure" perineurioma. They possessed thin bipolar processes and were arranged in laminar fascicles and whorls. In cellular areas, the cytoplasm was more eosinophilic and cell borders were poorly visible. In contrast, when the stroma was myxoid, it accentuated the shape of individual cells. As these morphological features of perineurial cell differentiation in NF are not entirely specific, EMA staining is recommended to prove the perineurial cell differentiation in neurofibromas. An additional immunohistochemical result of this study is the presence of numerous CD34-positive cells in all neurofibromas, which is similar to previous studies.