Actin-positive spindle cell lymphoma.

We report an unusual case of malignant lymphoma, large noncleaved B-cell type, exhibiting sarcomatoid and myxoid patterns and strong positive staining for muscle-specific actin. Despite vigorous chemotherapy, the 64-year-old male patient, who had lymphoma involving his right inguinal area, retroperitoneum, and anterior chest wall at the time of presentation, died 3 months later.

Postoperative spindle-cell nodule of urinary bladder with unusual intracytoplasmic inclusions.

Postoperative spindle-cell nodule of the urinary bladder (or in the absence of previous surgical procedure, inflammatory pseudotumor) is a reactive process of unknown etiology mimicking a sarcoma. Intracytoplasmic inclusion bodies were noted inside the atypical spindle cells on Diff-Quik stained smears in a recent case of this entity. Although fluorescence was noted in the inclusion bodies with monoclonal antibodies against the major outer membrane protein of the Chlamydia species, the exact nature of these inclusion bodies remains unknown.

'Rhabdoid' Wilms' tumor: an ultrastructural study.

We studied a 5-week-old infant who had a "rhabdoid" Wilms' tumor. Ultrastructural studies disclosed aggregates of cytoplasmic filaments that seemed to correspond with the eosinophilic cytoplasmic bodies seen by light microscopy, but did not uncover evidence of rhabdomyoblastic differentiation. The histogenesis of this subtype was not established, but origin from the metanephric blastema could not be ruled out.

Cystadenoma of the pancreas. An ultrastructural study.

A case of cystadenoma of the pancreas was studied at the light (LM) and the ultrastructural (EM) levels. The observation made under LM that the flattened epithelial cells lining the cystic spaces were similar to the centroacinar cells of a normal pancreas was supported by EM findings. Numerous glycogen granules were demonstrated in the cells, a feature characteristic of fetal but not adult centroacinar cells.

Pulmonary blastoma: an ultrastructural study with a brief review of literature and a discussion of pathogenesis.

A pulmonary blastoma is reported in a 19-year-old black female. The light and electron microscopic characterics are described; they are found to be similar to those of the fetal lung prior to the fourth gestational month. Although the ultrastructural features do not favor any particular theory of histogenesis of this unique tumor, evidence for the commonly held theory that the tumor arises from pluipotential pulmonary blastema seems tenuous.

Sezary syndrome with arthropathy. Report of a case.

A 65-year-old black female with Sezary syndrome had generalized intractable pruritus, erythroderma, alopecia, onychogryphosis, lumphadenopathy and hepatomegaly. Abnormal lymphocytes with large, convoluted and grooved nuclei (Sezary cells) were identified in the skin and peripheral blood. A striking feature of her disease was severe, deforming arthropathy of the hands and knees, a clinical finding which has been described previously in only one patient with Sezary syndrome.