[Show abstract][Hide abstract]ABSTRACT: Extraskeletal osteosarcoma (ESOS) occurs in approximately 1% of soft tissue sarcomas and 2-4% of all osteosarcomas. In particular, subcutaneous osteosarcoma is extremely rare, occurring in less than 10% of ESOS cases. This report presents a case of a subcutaneous tumor in the upper arm of a 79-year-old male. Imaging and pathological findings led to the conclusion that the soft tissue tumor should be diagnosed as subcutaneous osteosarcoma. Additionally, this case report documented the clinicopathological findings of the extraskeletal subcutaneous osteosarcoma in this case and discussed its clinical features by reviewing cases previously described in the literature.
[Show abstract][Hide abstract]ABSTRACT: The histogenesis of nevus sebaceous (NS) is unclear.
To elucidate the histogenesis of NS, cytokeratin (CK) profiles were examined immunohistochemically using 10 anti-keratin antibodies in the three stages of NS.
In the first stage, stratified differentiated keratins (CK1 and 10) were reduced, and basal keratin (CK14) was increased in the epidermis and primitive follicular structure (PFS). In the second stage, in addition to reduced CK1 and CK10 expressions and increased CK14 expression, CK17 expression was strongly expressed in the sebaceous ducts in proportion to the development of sebaceous gland. In the third stage, CK14, CK17 and CK19 were expressed in secondary tumors. CK16 was not detected throughout all stages of NS.
These results suggest that NS is not hyperproliferative but involves hamartomatous differentiation with undifferentiated keratins.
Article · Apr 2010 · International journal of dermatology
[Show abstract][Hide abstract]ABSTRACT: We present a case of malignant melanoma with a rhabdoid phenotype in a 44-year-old female with a quite unique and aggressive clinical course. Rhabdoid features are defined by characteristics such as sheets or solid trabeculae of neoplastic cells with large, vesicular, round to bean-shaped nuclei, prominent centrally located nucleoli, and abundant eccentric cytoplasm. Although various histological differential diagnoses were cited for the present case that showed 'rhabdoid features', most of them were excluded on the basis of the clinical history, tumor location, clinical behavior, and a broad panel of immunohistochemical stains. In the present case, the immunohistochemical findings were positive for vimentin, S-100 protein, melan-A, and EMA, but negative for HMB45, cytokeratin, CD34 and desmin. In addition, the positive expression of BAF47 was also recognized. These findings lead to the conclusion that this quite unique aggressive soft tissue tumor should therefore be diagnosed as malignant melanoma with a rhabdoid phenotype.
[Show abstract][Hide abstract]ABSTRACT: To clarify the histogenesis of keratoacanthoma, we studied keratin (K) expression in keratoacanthoma (KA) using 10 different anti-keratin antibodies against K1, K7, K8, K10, K14, K15, K16, K17, K18 and K19 and anti-filaggrin (filament aggregating protein) antibody. In the centre of KA, K1 and K10 expressions were declined, and K14 and K16 were detected in the tumour cells, suggesting differentiation towards the outer root sheath beneath the orifice of the sebaceous duct. These results suggest that KA differentiates towards the outer root sheath beneath the opening of the sebaceous duct.
Article · Apr 2008 · Journal of the European Academy of Dermatology and Venereology
[Show abstract][Hide abstract]ABSTRACT: Necrobiotic xanthogranuloma (NXG) is a rare marker for paraproteinemia. An 86-year-old woman had a one year history of large red-yellow to brown annular plaques involving all limbs. Biopsies showed a non-palisading granuloma with numerous multinucleated giant cells showing prominent elastophagocytosis and extensive areas of necrobiosis throughout the entire dermis. Complete loss of elastic fibers was observed in the central atrophic area of an annular plaque. Small vascular thromboses were also present. Laboratory findings revealed paraproteinemia of IgG-lambda type. Immunohistochemical staining detected the presence of roughly equal numbers of IgG-lambda-and IgG-kappa-staining plasma cells in the dermis. We diagnosed NXG with paraproteinemia with monoclonal gammopathy (IgG-lambda type) of unknown significance.
Article · Feb 2008 · Journal der Deutschen Dermatologischen Gesellschaft
[Show abstract][Hide abstract]ABSTRACT: Adamantiades-Behçet disease (ABD) may present with cutaneous and ophthalmologic findings. A 29-year old woman complained of fever and general fatigue, along with erythema nodosum and vesiculo-pustular lesions on the legs, acneiform lesions, genital ulcerations and painful oral ulcers. She also complained of reduced visual acuity, visual disturbance and blurred vision in the left eye. Her left visual acuity was 6/20. Light reflex in the left eye was reduced. The relative afferent pupillary defect (RAPD) was positive in the left eye where a central scotoma was present. The vitreous was clear; the optic disc, macula, retina and iris were all normal. Uveitis was not observed. The patient was diagnosed with ischemic optic neuritis (posterior optic neuropathy) with ABD. Histopathological findings taken from a blister on the leg showed subepidermal bulla, dense dermal neutrophil infiltration, and extravasation of erythrocytes, suggesting leukocytoclastic vasculitis. She was treated orally with high-dose corticosteroids (methylprednisolone 500 mg/d) for three days. Her general condition and ophthalmic symptoms resolved completely. Optic neuropathy with ABD is very rare; we know of two previous cases [1, 2] of ABD with ischemic posterior optic neuritis.
Article · Dec 2007 · Journal der Deutschen Dermatologischen Gesellschaft
[Show abstract][Hide abstract]ABSTRACT: We have studied cytokeratin (CK) expression in two cases of well-differentiated and poorly differentiated squamous cell carcinoma (SCC) arising from hidradenitis suppurativa (HS) (acne inversa). In both cases, type A (infundibular-like keratinized) epithelia were observed. In type A epithelia, CK 1 and 10 expressions were decreased, and CK 14 and 17 were detectable in the whole layers. CK 7, 8, 15, 16 and 18 were not detected in type A epithelia. In tumor nests of well-differentiated SCC, CK 1 and 10 expressions were downregulated, and CK 14 expression was upregulated. In tumor nests of poorly differentiated SCC, CK 1 and 10 were not expressed, but simple epithelial keratins (CK 8, 18 and 19) were expressed. These changes of CK expression are related to malignant transformation from the sinus tract (type A epithelium) in HS to SCC.
Article · Oct 2007 · Journal of Cutaneous Pathology
[Show abstract][Hide abstract]ABSTRACT: To elucidate the pathogenesis of abnormal keratinization in nevus comedonicus, we performed an immunohistochemical study using antikeratin and antifilaggrin (filament-aggregating protein) antibodies. There were no significant differences between nevus comedonicus and normal skin in cytokeratin expression. Although filaggrin was only detected in the granular layer in open comedones, filaggrin was detected in both superficial cells and also intermediate cells in closed comedones, suggesting that filaggrin is involved in the formation of closed comedones. The disorder of terminal differentiation related to filaggrin may play a role in the pathogenesis of abnormal keratinization in nevus comedonicus.
Article · May 2007 · Journal of Cutaneous Pathology
[Show abstract][Hide abstract]ABSTRACT: To clarify the histopathogenesis of Pinkus tumor (fibroepithelial basal cell carcinoma, FEBCC), we have studied cytokeratin (CK) expression in FEBCC using ten different anti-keratin antibodies against CK 1, 7, 8, 10, 14, 15, 16, 17, 18 and 19. Tumor nests consisted of two epithelial components: duct-like structures and basaloid cells of anastomosing strands. In duct-like structure, CK 1, 10, 14, 16, 17 and 19 were detected. CK expression of duct-like structure showed the hyperproliferative state of eccrine intraepidermal ducts. In basaloid cells of anastomosing strands, CK 14 and 17 were detectable. These results suggested that duct-like structure originates from the intraepidermal duct and proliferates to spread in the dermis.
[Show abstract][Hide abstract]ABSTRACT: Heterochromatin protein 1 (HP1) is associated with heterochromatin formation and the regulation of gene expression. In this study, we demonstrated that decreased HP1beta, but not HPla, mRNA and protein expression, correlates with invasive potential in five human melanoma cell lines, and we used immunohistochemistry to confirm that HP1beta expression is suppressed during melanoma progression. HPIP levels are decreased in (V600E)B-RAF-transformed mouse melanocytes, suggesting that HP1beta-mediated suppressive mechanisms correlate with melanoma oncogenesis. Expression of microphthalmia associated-transcription factor (MITF), an important melanocyte differentiation factor, is reduced in melanoma, which is correlated with poor prognosis. In CRL1579, SK-MEL-28 and HMV-II human melanoma cells in which HP1beta expression is reduced by RNAi, MITF RNA levels and invasiveness activities are differentially altered and are not correlated with each other. Our findings indicate that the (V600E)B-RAF mutation induces HPIbeta down-regulation, which causes epigenetic gene regulation associated with melanoma progression.
[Show abstract][Hide abstract]ABSTRACT: We report two cases of eccrine porocarcinoma (EPC), one of intrepidermal EPC (IEEPC) and one of intradermal invasive EPC (IDEPC) in an immunohistochemical study of cytokeratins (CK) using nine different anti-keratin antibodies against CK1, 7, 8, 10, 14, 16, 17, 18 and 19. IEEPC expressed terminal differentiated CK1 and CK10. In contrast, IDEPC expressed simple-epithelial keratins such as CK7, 8, 18 and 19. Keratin expression of IEEPC preserves the immunophenotypes of normal epidermis. IDEPC, however, expresses poorly differentiated keratin. These results suggest that the keratin profiles of EPC are correlated with the invasive degree and reflect the clinical prognosis of EPC.
[Show abstract][Hide abstract]ABSTRACT: An immunohistochemical study of cytokeratins (CK) in a case of trichilemmal carcinoma (TLC). CK expression showed the presence of CK 1, 10, 14 and 17, suggesting that TLC differentiates toward follicular infundibulum. In a comparison of CK expression between TLC and trichilemmoma, the absence of CK 15 and 16 in TLC may be related to transformation from trichilemmoma to TLC. Trichilemmal carcinoma (TLC) is a rare cutaneous tumor, and is considered as a malignant counterpart of trichilemmoma. The histogenesis of TLC remains unclear. The features of TLC resemble the outer root sheath. Monoclonal antibodies against cytokeratin (CK) are crucial markers for evaluating the origin of epithelial tumors and the stage of differentiation. To elucidate the origin and the stage of differentiation of TLC, an immunohistochemical study of CK was performed using nine different anti-keratin antibodies against CK1, 7, 8, 10,14,16,17, 18 and 19.
[Show abstract][Hide abstract]ABSTRACT: We experienced two cases of cutaneous dermoid cysts (DC). To elucidate the histogenesis of DC, we have studied cytokeratin (CK) expression in DC using ten different anti-keratin antibodies against CK1, 7, 8, 10, 14, 15, 16, 17, 18 and 19, and anti-filaggrin (filament aggregating protein) antibody. In the cyst wall of DC, CK1 and 10 were expressed in suprabasal layer, and CK14 was limited to the basal layer. In sebaceous gland-like structures, CK14 was detected in sebaceous acinus, and CK17 was detected in sebaceous duct. The other CKs were not detected. Filaggrin was intensely detected in the granular layer in the cyst wall of DC. CK expression profile of DC was similar to follicular infundibulum and sebaceous gland. These results suggested that DC differentiates towards follicular infundibulum and mature sebaceous gland.
[Show abstract][Hide abstract]ABSTRACT: We report a case of dermatofibrosarcoma protuberans (DFSP) which developed on the left lower abdomen of a 54-year-old male. Recently, the tumor with a ten-year history rapidly grew larger. Then, the patient was admitted to our hospital for surgical treatment. The tumor was excised, and was histologically diagnosed as a DFSP based on the characteristic histopathological findings with storiform pattern and intensive CD34 expression on the tumor cells. Then, the peri-lesional tissue was excised with a 5cm of marginal tumor free skin. No obvious sign of recurrence has been identified during 9 months follow-up. [Skin Cancer (Japan) 2004; 19: 212-214]