ABSTRACT
BACKGROUND: Pineal gland lesions are rare, with only a few cytologic descriptions occurring in the literature, according to the authors' knowledge. The current article describes the cytopathologic characteristics of 20 such lesions with discussion of differential diagnoses. METHODS: Cytologic material was obtained either by fine-needle aspiration biopsy (FNAB) under stearotactic radiologic guidance or by touch imprinting (TI) at the time of frozen sectioning. The 20 specimens include pineoblastoma (five specimens), pineocytoma (four specimens), astrocytoma (three specimens), germ cell tumor (three specimens), meningioma (one specimen), epidermoid cyst (three specimens), and pineal cyst (one specimen). Smears were stained with Diff-Quik and with Papanicolaou and hematoxylin and eosin stains. In selected specimens, immunoperoxidase (IPOX) stains were performed on cell block sections using synaptophysin, neuron-specific enolase, placental alkaline phosphatase, glial fibrillary acidic protein, leukocyte common antigen, cytokeratins, and human chorionic gonadotropin antibodies. RESULTS: Several cytomorphologic characteristics unique to each lesional category with occasional overlapping features were observed. The unique features included the following: small, hyperchromatic, round to oval cells with frequent rosetting (pineocytoma), with a few specimens in addition showing hypercellularity, crowding, mitoses, and necrosis (pineoblastoma); pleomorphic round cells in a fibrillary background (astrocytoma); large polygonal cells with prominent nucleoli and clear cytoplasm (germ cell tumor); spindled fibroblastic cells (meningioma); anucleate squames and mature squamous cells (epidermoid cyst); and small uniform polygonal cells (pineal cyst). When necessary, IPOX studies supported the morphologic diagnoses. CONCLUSIONS: FNAB and TI cytology were found to provide a rapid and reliable diagnosis of pineal lesions. This is particularly important when dealing with minute amounts of tissue material. Both techniques appeared to provide equally good cytomorphology on smears. IPOX studies played an important complementary role in difficult cases when performed on cell blocks.
Subject(s)
Cysts/pathology , Pineal Gland , Pinealoma/pathology , Adolescent , Adult , Astrocytoma/pathology , Biopsy, Fine-Needle , Child , Child, Preschool , Diagnosis, Differential , Epidermal Cyst/pathology , Female , Germinoma/pathology , Humans , Infant , Male , Middle AgedABSTRACT
Whipple disease is a rare infection characterized clinically by diarrhea, fever, weight loss, arthralgia, malabsorption, and other systemic manifestations. The etiologic agent, Tropheryma whipplei, has been cultured only rarely. By using a polyclonal rabbit antibody produced against a cultured strain of T whipplei, tissue sections from 18 patients with Whipple disease were studied. Specimens from patients with histologic mimics and other infections served as control specimens. Immunostaining was identified in all 18 patients. Granular immunostaining was observed similar to that in periodic acid-Schiff (PAS) stains. In 2 patients, immunostaining was identified in specimens negative by H&E and PAS stains. In 4 patients studied before and after antibiotic therapy, immunostaining was retained but diminished in intensity and quantity. Immunostaining was not identified in any control specimen. Immunohistochemical analysis is a sensitive and specific method for the diagnosis of Whipple disease in paraffin-embedded tissue and may provide new opportunities to investigate the pathogenesis of the infection.
Subject(s)
Actinobacteria/isolation & purification , Immunohistochemistry/methods , Whipple Disease/pathology , Actinobacteria/immunology , Adult , Antibodies, Bacterial/analysis , Antigens, Bacterial/immunology , Brain/microbiology , Brain/pathology , Female , Humans , Intestine, Small/microbiology , Intestine, Small/pathology , Lymph Nodes/microbiology , Lymph Nodes/pathology , Male , Middle Aged , Paraffin Embedding , Retrospective Studies , Sensitivity and Specificity , Whipple Disease/microbiologyABSTRACT
Fibromatoses of the breast are nonmetastasizing tumors, but can be infiltrative and locally recurrent. Breast fibromatoses are rare, and their specific genetic alterations have not been elucidated. However, their occasional occurrence in patients with familial adenomatous polyposis (FAP) and their morphologic identification with other deep fibromatoses (desmoid tumors) suggest that alterations of the APC/beta-catenin pathway might be involved in the pathogenesis of sporadic and FAP-associated breast fibromatoses. We analyzed somatic beta-catenin and APC gene mutations in 33 breast fibromatoses (32 sporadic and 1 FAP-associated) using immunohistochemistry for beta-catenin, 5q allelic loss assays, and direct DNA sequencing for exon 3 of the beta-catenin gene and the mutation cluster region of the APC gene. Nuclear accumulation of beta-catenin was present in the stromal tumor cells in most (82%) cases but not in normal stroma or mammary epithelial cells. Somatic alterations of the APC/beta-catenin pathway were detected in 79% of breast fibromatoses, including activating beta-catenin gene mutations in 15 cases and somatic APC alterations (mutation or 5q allelic loss or both) in 11. These findings indicate that alterations of the APC/beta-catenin pathway with resultant nuclear translocation of beta-catenin are important in the pathogenesis of both sporadic and FAP-associated breast fibromatosis. The spectrum of beta-catenin and APC alterations is similar to that described for desmoid tumors of the abdomen, paraspinal region, and extremities.
