Small asymptomatic cysts of the pineal gland represent a common incidental finding in adults undergoing computerized tomography or magnetic resonance (MR) imaging or at postmortem examination. In contrast, large symptomatic pineal cysts are rare, being limited to individual case reports or small series. The authors have reviewed 24 cases of large pineal cysts. The mean patient age at presentation was 28.7 years (range 15 to 46 years); 18 were female and six male. Presenting features in 20 symptomatic cases included: headache in 19; nausea and/or vomiting in seven; papilledema in five; visual disturbances in five (diplopia in three, "blurred vision" in two, and unilateral partial oculomotor nerve palsy in one); Parinaud's syndrome in two; hemiparesis in one; hemisensory aberration in one; and seizures in one. Four lesions were discovered incidentally. Magnetic resonance imaging typically demonstrated a 0.8- to 3.0-cm diameter mass (mean 1.7 cm) with homogeneous decreased signal intensity on T1-weighted images, increased signal intensity on T2-weighted images, and a distinct margin. Hydrocephalus was present in eight cases. The cysts were surgically excised via an infratentorial/supracerebellar approach (23 cases) or stereotactically biopsied (one case). Histological examination revealed a cyst wall 0.5 to 2.0 mm thick comprised of three layers: an outer fibrous layer, a middle layer of pineal parenchymal cells with variable calcification, and an inner layer of hypocellular glial tissue often exhibiting Rosenthal fibers and/or granular bodies. Evidence of prior hemorrhage, mild astrocytic degenerative atypia, and disorganization of pineal parenchyma were often present. Postoperative follow-up review in all 24 cases (range 3 months to 10 years) revealed no complications in 21, mild ocular movement deficit in one, gradually resolving Parinaud's syndrome in one, and radiographic evidence of a postoperative venous infarct of the superior cerebellum with ataxia of 1 week's duration in one. Of the patients referred for study, the cysts were most often initially misdiagnosed as a pineocytoma in eight and a pilocytic astrocytoma in three. Only two patients were correctly diagnosed as having pineal cysts. This stresses the importance of recognizing the histopathological spectrum of pineal cysts, as well as correlation with radiographic findings, if a correct diagnosis is to be attained.

Background. Giant cell tumors (GCT) usually involve the epiphyses of long bones and only rarely involve the metaphysis or diaphysis without epiphyseal extension. Methods. This report presents the clinical and pathologic features of 14 patients with metaphyseal and diaphyseal GCT. Of these tumors, 10 were metaphyseal; 2, metadiaphyseal; and 2, diaphyseal. Results. The sites of involvement included the proximal tibia in six patients, distal radius in three, proximal fibula in one, distal fibula in one, distal ulna in one, proximal humerus in one, and distal femur in one. Radiographically, the tumors were lucent, and the majority were sharply marginated without sclerosis. By contrast with conventional epiphyseal GCT, which generally appear in the mature skeleton, a large proportion (50%) of the GCT in this series were in patients who had open epiphyseal growth plates. Despite the unusual clinical presentation, the behavior of metaphyseal and diaphyseal GCT was similar to that of the typical epiphyseal GCT. There was a 43% recurrence rate after curettage in this series. Conclusions. It is important to distinguish this subset of GCT from other giant cell‐rich lesions more common in these sites, including aneurysmal bone cyst, osteosarcoma, and nonossifying fibroma.

An unique case of high‐grade phyllodes tumor (cystosarcoma phyllodes) arising in the seminal vesicle is reported. A 61‐year‐old man had symptoms of urinary obstruction, and ultrasonography and computed tomography showed a large mass posterior to the bladder. Using cystoprostatoseminovesiculectomy, a high‐grade phyllodes tumor of the left seminal vesicle was found that did not involve the bladder or prostate. Histologically, the tumor consisted of benign irregular slit‐like glands set in a mitotically active cellular sarcomatous stroma. The epithelium displayed intense cytoplasmic immunoreactivity with all keratin proteins (AE1/AE3, CAM 5.2, and high‐molecular‐weight keratin [clone 34βTE12]). The stromal cells were strongly positive for vimentin, and approximately 30% were positive for muscle‐specific actin and desmin. Four years after resection, a lung metastasis was removed, which was histologically and immunohistochemically identical to the seminal vesicle tumor. This case represents the malignant end of the range of phyllodes tumors (cystosarcoma phyllodes). Like similar tumors in the breast and prostate, phyllodes tumors of the seminal vesicle should be considered high‐grade lesions (malignant) in which there is significant mitotic activity, stromal pleomorphism, and stromal overgrowth.

The first three well‐documented cases of pure, extraskeletal telangiectatic osteosarcoma of the soft tissues are presented in this article. The distinctive gross features were a predominance of large, blood‐filled spaces, which, on histologic examination, were large blood‐filled cavities in association with cyst‐like walls containing anaplastic spindle cells and definite osteoid production in two of three cases. One of the cases is of additional clinical interest because the teen‐aged daughter of the woman patient had died 1 year previously of a high‐grade intramedullary osteosarcoma of bone.

ABSTRACT:We describe a unique case of chronic lymphocytic leukemia (CLL) in a patient who presented with bitemporal hemianopsia, adrenal insufficiency, and gonadotrophin deficiency. Studies revealed an enhancing intrasellar mass with suprasellar extension and displacement of the optic chiasm. Peripheral blood and cerebrospinal fluid (CSF) studies disclosed a monoclonal IgM kappa expressing B-cell CLL. Biopsy of the pituitary mass revealed dense infiltration of the pituitary gland by leukemic cells. This is, to our knowledge, the first reported case of CLL presenting as a pituitary mass lesion.