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Biomedical subjects

M E Paiva

Publications and source records attributed to M E Paiva.

7 recordsLinked to original sources
PubMed1991

Dermatofibrosarcoma protuberans. A histological and ultrastructural study of 11 cases with emphasis on the study of recurrences and histogenesis.

Eleven cases of dermatofibrosarcoma protuberans (DFSP) (6 male: 5 female; mean age +/- SD: 48.7 +/- 16.1 years) were reviewed in an attempt to correlate the histological and ultrastructural findings with the recurrence pattern of these tumours and to shed light on their histogenesis. Six (54.5%) of the tumours recurred: 3 with a similar appearance to the primary tumours, 2 with fibroblastic malignant fibrohistiocytic pattern (F-MFH), and one with fibrosarcomatous features (F), confirmed ultrastructurally. In one primary tumour with associated F features there were two recurrences. The ultrastructural findings of 6 primary tumours (2 with and 4 without recurrences) showed a predominance of primitive mesenchymal cells. The comparison between the features (sex, age, site, necrosis, mitotic rate size) of recurring DFSP vs DFSP without recurrences did not yield any significant difference. At follow-up (range: 11-108 months) all patients were alive and well. These findings support the assumption that DFSP originates from primitive mesenchymal cells that are able to show, at least, F and F-MFH differentiation, and corroborate the low-grade malignancy of DFSP regardless of their macroscopic, histologic and ultrastructural characteristics.

Adult↗
PubMed1985

Lymphoid hypophysitis in a patient with lymphoid thyroiditis, lymphoid adrenalitis, and idiopathic retroperitoneal fibrosis.

We describe the autopsy findings in a 24-year-old woman with a clinical picture of pituitary and adrenal insufficiency which had its onset shortly after a normal pregnancy and delivery of a normal infant, two years before the mother's death. There were heavy lymphocytic infiltrations of the adenohypophysis, thyroid, and adrenals as well as diffuse retroperitoneal fibrosis with numerous perivascular lymphocytic infiltrates. It is concluded that lymphoid hypophysitis probably represents the hypophyseal counterpart of other endocrine autoimmune disorders and that immune mechanisms may also play a role in the pathogenesis of the so-called idiopathic retroperitoneal fibrosis.

Adrenal Glands↗
PubMed1983

Hodgkin's disease with predominant infradiaphragmatic involvement and massive invasion of the bone marrow. A necropsic study of nine cases.

The authors report the results obtained in the necropsic study of nine cases of the so-called acute, visceral form of Hodgkin's disease (HD). Most of the patients (six men and three women, ranging from 42 to 74 years of age) lacked peripheral lymphadenopathies and had fever, weight loss, abnormality of hepatic function, and pancytopenia. Mixed cellularity was diagnosed in two, diffuse fibrosis in four, and reticular subtype of lymphocyte depletion in three cases. Despite the predominant infradiaphragmatic involvement, supradiaphragmatic lymph nodes were involved in six and tonsils in three cases. Spleen and bone marrow were involved in eight cases and the liver was involved in seven cases. In four cases there were also lesions in other extralymphoid organs. The involvement of the bone marrow was widespread and showed concurrent myelofibrosis and/or other signs of hematopoietic disturbance. There was a close relationship between the presence of vascular invasion (seven cases) and the extent of HD spread. It is concluded that despite its peculiarity, this form of HD fits the classic model of unicentric origin, lymphogenic contiguous spread, and hematogeneous dissemination, and should not be identified with any particular histologic type of HD.

Adult↗
PubMedDate not supplied

Malignant primitive neuroepithelial tumour of soft tissues mimicking a cellular ependymoma.

A malignant small blue-cell soft tissue tumour in a 13 year-old girl is reported. By light microscopy the tumour showed prominent pseudo-rosettes suggesting peripheral neuroepithelial tumour (PNET) with ependymal differentiation or extraspinal cellular ependymoma. Ultrastructural and immunocytochemical findings helped in excluding an ependymal neoplasm (low-grade malignancy) and supported the diagnosis of malignant primitive PNET mimicking a cellular ependymoma (high-grade malignancy).

Adolescent↗