Evidence Of Epithelial Differentiation Research Articles

SMARCA4-deficient undifferentiated thoracic tumor: A case report

SMARCA4-deficient undifferentiated tumors (SMARCA4-DUTs) present with diverse clinical manifestations and progress to metastasis and even cause death within a few months. This novel subset of undifferentiated tumors occurs in the middle-aged population and is strongly associated with a smoking history. Distinguishing it from other malignancies is challenging. A 62-year-old man presented with chest pain for 7 d. The patient had no respiratory symptoms and normal pulmonary function test results. The patient had been a smoker for 8 years and quit smoking 2 years ago. Chest computed tomography revealed a huge mass involving the left upper and lower lung lobes with pericardial invasion and multiple metastases. Tumor samples were obtained using open frozen biopsy, after several unsuccessful attempts. The tumor was composed of sheets of undifferentiated disclosive cells with vesicular nuclei and prominent nucleoli. The differential diagnosis included high-grade lymphoma, germ cell tumor, NUT carcinoma, undifferentiated carcinoma, and sarcoma. The tumor cells were large, arranged in sheets, and did not exhibit glandular or squamous differentiation. Frequent foci of necrosis were noted. There was no evidence of epithelial differentiation on immunohistochemical staining. The SMARCA4 stain showed complete loss of expression of SMARCA4, which is diagnostic. In the present case, thoracic SMARCA4-DUT was diagnosed based on clinical features, absence of epithelial differentiation, and negative SMARCA4 expression.

Cytokeratin positive T cell malignant lymphoma.

A high grade T cell malignant lymphoma is described in which weak staining of tumour cells for leucocyte common antigen and T cell markers coexisted with strong positive cytoplasmic staining...

On the Origin and Diagnostic Criteria of Olfactory Neuroblastoma.

The origin and diagnostic criteria of olfactory neuroblastoma are still under dispute. Tosolve these problems, seven cases of olfactory neuroblastomas satisfying diagnostic criteria of Choi and Anderson were analyzed immunohistochemically by using antibodies to markers expressed in developing and mature human olfactory placode-derived neurons such as keratin, a 34 kDa epithelial membrane glycoprotein, luteinizing-hormone-releasing-hormone (LHRH) and to other neural tissue markers. Ultrastructural analysis was also carried out. Five cases were identified as neuroblastomas because neurites were disclosed in them. All of these five cases had widespread immunoreactivity to an antibody to a 34 kDa epithelial membrane glycoprotein (Ber-EP4) in the tumor cell bodies and/or neuritic processes. They also contained keratin positive cells. LHRH was demonstrated in two of these Ber-EP4 positive neuroblastomas. The spectrum of immunohistochemical findings of these five cases was identical to the normal neuroblasts arising from olfactory placode.Accordingly, it is concluded that neuroblastoma of true olfactory placodal origin does exist. The diagnostic criteria of this tumor is as follows: demonstration of neurites and immunoreactivity to Ber-EP4 and/or LHRH. Keratin is not necessary to regard as an evidence of epithelial differentiation in this tumor.

Primary Osteosarcoma of the Uterus: Report of a Case with Immunohistochemical Analysis

Primary osteosarcoma of the uterus is an extremely rare neoplasm, and its immunohistochemical characteristic is unknown. We report a case of osteosarcoma occurring primarily in the uterine corpus of a 67-year-old woman with lower abdominal pain. The excised tumor showed bony inconsistency and histologically displayed a "pure" osteosarcoma of the uterus. Immunocytochemically, the tumor cells were positive for vimentin but negative for epithelial markers. The patient died 4 months after surgery because of developed local recurrence and pulmonary metastases. In conclusion, uterine osteosarcoma differs from malignant mixed Müllerian tumor (MMMT) in biological behavior, macroscopic and histologic features, and immunohistochemical profile. Osteosarcoma shows more aggressive behavior than MMMT, and displays nonpolypoid feature in appearance and no evidence of epithelial differentiation.

Carcinosarcoma and spindle cell carcinoma of the lung: Clinicopathologic and immunohistochemical studies

We examined pulmonary carcinomas with prominent sarcoma-like lesions both clinicopathologically and immunohistochemically. Grossly, two tumors had predominantly endobronchial growths, four bulky parenchymal growths, and two endobronchial, parenchymally mixed growths. In these eight patients, six tumors were completely resected, one patient was given irradiation only, and one patient died in the early postoperative period. On the basis of specific differentiation of the sarcoma-like lesions, the tumors were separated into three groups: two with "true" sarcoma differentiated into soft tissues such as striated muscle or osteoid tissue; three with a fibromatous sarcoma resembling atypical pseudosarcomatous stroma; and three with spindle cell carcinoma with evidence of epithelial differentiation. The prognosis was poor, and tumors with specific differentiation into rhabdomyosarcoma, chondrosarcoma, or spindle cell carcinoma progressed more rapidly than did those with a fibromatous sarcoma. Because the fibromatous sarcoma-like lesions were found to relate to a longer survival time for the patients, we wish to emphasize that a distinction of sarcomatous components should be made with regard to assessing the prognosis of pulmonary carcinoma with sarcoma-like lesions.

The use of electron microscopy and immunocytochemistry to characterise spontaneously-arising, transplantable rat tumors

When examined by light microscopy, transplanted animal tumors frequently bear little resemblance to the original neoplasm. If such tumors are to be used as models of human cancer they should be characterised as regards extant rather than historical features. Consequently, we have examined, by electron microscopy and immunocytochemistry, five spontaneously arising tumors transplantable in the WAB/Not rat that are currently diagnosed on the basis of historical features only. A typical sarcoma was used for comparison. Of four spontaneously arising tumors previously classified as carcinoma, Sp4 possessed epithelial features on both ultrastructural and immunocytochemical analysis, Sp107 on ultrastructural analysis only and Sp15 and Sp22 by neither technique. Expression of vimentin was most marked with Sp15 and Sp107. The putative sarcoma, Sp24, showed clear evidence of epithelial differentiation but no evidence of vimentin expression. This study (a) records the phenotypic drift of experimental tumors on transplantation (most clearly with Sp107) and the co-expression of cytokeratins and vimentin in putative carcinomas, (b) confirms the inadequacy of routine histology for accurate characterisation of such tumors and (c) details techniques for a more thorough assessment of state of differentiation that should guide the choice of experimental model.

Anaplastic thyroid carcinoma: an ultrastructural study of 10 cases.

Anaplastic carcinoma of the thyroid is an aggressive, rapidly fatal neoplasm that is generally believed to arise from the epithelium of the thyroid follicle. When differentiated carcinoma is not present, the diagnosis can be difficult and confusion with a sarcoma is frequently a problem. Ten anaplastic thyroid carcinomas have been examined by light and electron microscopy and compared with two biologically aggressive, solid follicular carcinomas. Ultrastructural study revealed evidence of epithelial differentiation in all the anaplastic carcinomas, confirming their origin from thyroid follicular cells. The study illustrates the value of electron microscopy in establishing the diagnosis of anaplastic carcinoma and in differentiating it from sarcoma.