Biomedical subjects

P van Heerde

Publications and source records attributed to P van Heerde.

58 records · Page 4Linked to original sources

PubMedDate not supplied

Fine needle aspiration cytology of radiation-induced changes in nonneoplastic breast lesions. Possible pitfalls in cytodiagnosis.

The range of radiation-induced changes in fine needle aspiration (FNA) smears of the breast is described. In 41 of more than 800 patients who underwent breast-conserving treatment, a palpable breast lesion developed, and FNA was performed. In six cases, a recurrent carcinoma was present. In the remaining cases, three patterns of nonneoplastic lesions could be discerned: epithelial atypia (14 cases), fat necrosis (10 cases) and poorly cellular smears without epithelial atypia or fat necrosis (13 cases). It is important to be familiar with the patterns of radiation-induced epithelial atypia, since such atypia may lead to a misdiagnosis of recurrent carcinoma. These atypical cells may show impressive anisocytosis and anisonucleosis; however, the nuclear/cytoplasmic ratio remains normal and an admixture of bipolar cells is present. Cell dissociation and necrotic cell debris, as often seen in breast cancer smears, were never encountered in FNA smears from radiated nonneoplastic breasts.

Adult↗

PubMedDate not supplied

Fine needle aspiration biopsy diagnosis of rhabdomyosarcoma. An immunocytochemical study.

Specific antibodies against desmin, skeletal muscle actin and myosin were assessed for their usefulness in the cytodiagnosis of five rhabdomyosarcomas: one well-differentiated, two moderately differentiated and two poorly differentiated lesions. Acetone-fixed smears from fine needle aspiration biopsies and the avidin-biotinyl-peroxidase complex technique were used. All aspirates were positively immunostained with antibodies against desmin and actin. Myosin could only be detected in the moderately and well-differentiated tumors. The percentage of tumor cells positive for any of the three proteins was positively correlated with the overall degree of differentiation. However, the number of positive tumor cells decreased in the sequence desmin-actin-myosin. The results indicate the value of antibodies, especially those against skeletal muscle actin, in aiding in the cytodiagnosis of rhabdomyosarcoma, particularly with respect to its differential diagnosis from small round cell tumors in children and pleomorphic sarcomas in adults.

Actins↗

PubMedDate not supplied

Synovial nature of pathologic periarticular structures, including subcutaneous nodules. descent from embryonic arthrogenic fibroblasts: a hypothesis.

In the embryo the periarticular fibroblasts were the producers of the greater part of the joint they surround in later life, as well as of the tendon sheaths and bursae. It is postulated that adult fibroblasts have retained atavistic arthrogenic properties, and may react to traumatizing, inflammatory and oncogenic stimuli by forming periarticular joint-like structures: "arthromas" such as ganglia, meniscal cysts, synovial cysts, synovial sarcoma and subcutaneous nodules. The arthroid nature of these growths manifests itself by the presence of a central cavity, which can be identified as a synovial cavity by histologic, histochemical and electron-microscopic methods. In case of affection of the joint all of these adnexa may be involved. A resemblance of these structures to embryonic joint tissues has been noted for years. The nature of the subcutaneous nodule is discussed at some length. It may contain one or more synovial clefts; synovial elements may be found in its centre by histochemistry and electron-microscopy. Recent and personal findings shed a new light on palisading cells, which may be fibroblasts, having taken up again their embryonic task as synovioblasts. From periarticular fibroblasts thus three kinds of tumors may arise; benign (ganglia, cysts, subcutaneous nodules), malignant (synovial sarcoma) and "semi-malignant" (pannus in rheumatoid arthritis).

Arthritis, Rheumatoid↗

PubMedDate not supplied

Sarcoma arising from interdigitating cells. Cytology and cytochemistry.

The cytologic features of a highly malignant sarcomatous tumor in a 37-year-old male, arising from interdigitating cells and localized in the mediastinum, lymph nodes and skin, are described. Cytologically this sarcoma was characterized by large cells with ill-defined, faintly basophilic cytoplasm, monocytoid or multilobulated nuclei and a reticular chromatin structure; very prominent nucleoli were seen in some of the cells. Some of the tumor cells were spindle shaped. The ultrastructurally characteristic invaginations of the cell membrane were not obvious in the cytologic smear, although the nuclear membrane showed deep, narrow, channel-like indentations. The specific ultrastructural, immunologic and cytochemical characteristics of the interdigitating cells were recognized in the tumor cells. Adenosine triphosphatase was present in the tumor cells in large amounts, while acid phosphatase, acid alpha-naphthyl acetate esterase and other enzymes were absent. The described tumor must be considered another tumor of the mononuclear phagocyte system; the proposed name is "interdigitating-cell sarcoma."

Acid Phosphatase↗