M-T Sung | PubMed Health

PubMed2007

OCT4: biological functions and clinical applications as a marker of germ cell neoplasia.

Germ cell tumours (GCTs) are a heterogeneous group of neoplasms, which develop in the gonads as well as in extragonadal sites, that share morphological patterns and an overall good prognosis, owing to their responsiveness to current surgical, chemotherapeutic, and radiotherapeutic measures. GCTs demonstrate extremely interesting biological features because of their close relationships with normal embryonal development as demonstrated by the pluripotentiality of some undifferentiated GCT variants. The similarities between GCTs and normal germ cell development have made it possible to identify possible pathogenetic pathways in neoplastic transformation and progression of GCTs. Genotypic and immunophenotypic profiles of these tumours are also useful in establishing and narrowing the differential diagnosis in cases of suspected GCTs. Recently, OCT4 (also known as OCT3 or POU5F1), a transcription factor that has been recognized as fundamental in the maintenance of pluripotency in embryonic stem cells and primordial germ cells, has been proposed as a useful marker for GCTs that exhibit features of pluripotentiality, specifically seminoma/dysgerminoma/germinoma and embryonal carcinoma. The development of commercially available OCT4-specific antibodies suitable for immunohistochemistry on paraffin-embedded specimens has generated increasing numbers of reports of OCT4 expression in a wide variety of gonadal and extragonadal GCTs. OCT4 immunostaining has been shown to be a sensitive and specific marker for seminomatous/(dys)germinomatous tumours and in embryonal carcinoma variants of non-seminomatous GCTs, whether in primary gonadal or extragonadal sites or in metastatic lesions. Therefore, OCT4 immunohistochemistry is an additional helpful marker both in the differential diagnosis of specific histological subtypes of GCTs and in establishing a germ cell origin for some metastatic tumours of uncertain primary. OCT4 expression has also been reported in pre-invasive conditions such as intratubular germ cell neoplasia, unclassified (IGCNU) and the germ cell component of gonadoblastoma. Additionally, OCT4 immunostaining shows promise as a useful tool in managing patients known to be at high risk for the development of invasive GCTs.

Biomarkers, Tumor↗

PubMed2002

Sclerosing perineuriomas affecting bilateral hands.

Sclerosing perineurioma is a rare, recently described variant of perineurioma that tends to affect the fingers and palms of adolescents or young adults. The process typically presents as a painless, well-circumscribed, unencapsulated nodule involving subcutis or reticular dermis. To our knowledge, all of the previously reported sclerosing perineuriomas were solitary. Hence, we report a 16-year-old boy, without stigmata of neurofibromatosis, who developed one sclerosing perineurioma in the right palm and another on the left index finger. Microscopically, tumours at both sites revealed small epithelioid and plump spindle cells with trabecular, whorled, or Indian file growth pattern enmeshed within extensively hyalinizing stroma. Immunohistochemically, the tumour cells showed strong reactivity for EMA but negative staining for S-100 and neurofilament. Ultrastructually, the tumour cells in both lesions exhibited features of perineurial cells, including discontinuous external basal lamina, occasional pinocytotic vesicles, and encirclement of abundant collagen fibrils by the interdigitating cytoplasmic processes. This case confirms the fact that sclerosing perineurioma is not always solitary.

Adolescent↗

PubMed2002

Atypical leiomyoma of the urinary bladder--a rare tumor occurring in a young female with concurrent breast carcinoma--an influence of sex steroid hormone?

Smooth muscle tumors are uncommon in the urinary bladder, and atypical leiomyoma of the urinary bladder is extremely rare. We report a case of atypical leiomyoma with a concurrent breast carcinoma and discuss the pathologic features, the possible etiology and clinical outcome of the tumor.

Adult↗