Crystalline foreign particulate material in hernia sacs

The subserosal stroma of hernia sacs consistently contains birefringent particulate material, in amounts greater than those observed in other intra-abdominal organs. The major component of this material was shown in the present study to be talc; thus, it cannot be of endogenous origin. Cellular response to this foreign material is remarkably slight. Possible sources of the material and mechanisms of access to the hernia sac were examined in a search of the available literature. It is proposed that the probable source is ingestion with food or, more likely, medications and that the particles reach the peritoneal cavity by migration through the intact intestinal wall. They probably reach the hernia by sedimentation in peritoneal fluid and subsequently migrate into the subserosa. The virtual absence of response to the particles is attributed to their composition (silicate) and their relatively small size (up to about 10 microns) compared with the particles in talc granulomas (up to at least 50 microns).     

Histologic response of normal human endometrium to steroid hormones in athymic mice

Despite the widespread use of hormonal therapy for menopausal symptoms, oral contraception, and treatment of metastatic breast carcinoma, information concerning the histologic and biologic effects of individual sex steroids on the human endometrium remains incomplete. Repetitive endometrial biopsy is impractical, and ethical constraints limit the dosage and duration of administration for some steroids. The ovariectomized athymic mouse was investigated as a host for human endometrium in which the hormonal milieu may be manipulated and the histologic response determined. Minced proliferative-phase endometrium from hysterectomy specimens of normally cycling women was inserted into the subcutis of 4- to 6-week-old mice. Proliferation of endometrial gland cells occurred in the transplanted endometrium of estradiol-treated mice, while the complete sequence of secretory-phase events, including subnuclear vacuolization, luminal secretion, and decidualization of stroma, was observed during a 14-day period of treatment with estradiol and progestin (medroxyprogesterone acetate). Progestin treatment alone also caused secretory-phase changes, but the response was delayed and appeared weaker. The transplanted endometrium in control mice appeared to be inactive. These observations provide support for the use of this model to study the histologic response of human endometrium to sex steroids.     

Isolated xanthomatosis of the small bowel

A case of xanthomatosis of the small bowel is described. Beginning with the proximal jejunum, an 85-cm segment of small bowel was distorted by regularly spaced nodular accumulations of lipid-laden macrophages that expanded the submucosa and muscularis and extended to the serosal surface. The conditions often associated with xanthomatosis were not found in this patient.     

Lung cancer heterogeneity: a blinded and randomized study of 100 consecutive cases

The heterogeneity of lung carcinomas was recognized in the past, but few previous studies attempted to quantitate this heterogeneity. In the present study 100 consecutive cases of lung carcinoma (65 surgical resections and 35 autopsies) were collected, and either the entire tumor or ten blocks were examined in a blinded and randomized fashion using the revised (1981) WHO classification. At least three of five panelists agreed on the major histologic type present for 94 per cent of the slides. Agreement for the diagnosis of small cell carcinomas (at least four of five observers) was 98 per cent, but only 72 per cent agreement was attained for the subtyping of small cell carcinomas (e.g., oat cell versus intermediate). Only 34 per cent of the cases were homogeneous according to the majority of the panelists. An additional 21 per cent of the cases showed minor (subtype) heterogeneity (e.g., mixtures of acinar and papillary patterns in adenocarcinoma). Forty-five per cent of the cases showed major heterogeneity, i.e., at least one slide from the case showed a major histologic type different from that of the remainder. Seven small cell carcinomas were homogeneous, whereas in eight cases mixtures of small cell and other cell types were seen. In all but one of the cases involving bronchioloalveolar cell patterns, other patterns of adenocarcinoma were present elsewhere in the tumor. In all six cases involving giant cell carcinoma patterns, adenocarcinoma patterns were also present in some sections. Heterogeneity was identified by extensive sampling of the entire tumor and was seldom recognized in biopsy specimens.     

Subclassification of small cell cancer of the lung: the Southeastern Cancer Study Group experience

Cancers in more than 300 patients being treated by Southeastern Cancer Study Group protocols for small cell carcinoma of the lung (SCCL) were subclassified as oat cell or intermediate types by criteria developed by two groups of investigators. With Cox survival and logistic regression models, no differences in survival or responsiveness to therapy were found between these types of tumors. These and previously published results suggest that the only intermediate tumors worth distinguishing are the "22/40" tumors with morphologic features precisely intermediate between those of SCCL and non-SCCL, including mildly vesicular nuclei, common small nucleoli, and rims of stained cytoplasm. Such tumors are the dividing point between SCCL and non-SCCL and constitute a small fraction of the spectrum from SCCL to non-SCCL.     

Granulocytic sarcoma of the hard palate: Report of the first case

A case of granulocytic sarcoma of the hard palate in an elderly woman is presented. The diagnosis was suspected on the basis of histologic findings in routine tissue sections and confirmed by cytochemical and electron microscopic studies. No systemic evidence of myeloid leukemia or of any other myeloproliferative disorder was documented in the patient, who died of an unrelated cause shortly after diagnosis.     

Congo red-negative amyloidosis-like glomerulopathy

Three cases of amyloidosis-like glomerulopathy are presented in which renal amyloidosis was initially diagnosed on the basis of ultrastructural findings, despite negative Congo red staining. The histologic and immunofluorescence findings and, on careful examination, ultrastructural features of this amyloidosis-like glomerulopathy all serve to distinguish it from true amyloidosis. The clinical behavior suggests that it is a primary glomerulopathy since, with time, no other systems become involved.     

Less utilization of the clinical laboratory produces disproportionately small true cost reductions

Decreases in true expenses in the hospital clinical laboratory consequent to reduced utilization were estimated from four models. Each category of direct expense was adjusted according to projections and confirmed to the extent possible by actual experience. No projections of reductions in indirect expenses were made. Savings with reductions in utilization of 10 and 50 per cent of a single high-volume automated test amounted to 1.32 and 18.11 per cent of total expenses, respectively. Savings with reductions of 10 and 50 per cent in utilization of all tests amounted to 3.88 and 21.55 per cent, respectively. These modest savings should be important to the financial planning efforts of laboratory managers and institutional administrators confronted with cost-reduction mandates.     

An immunohistologic study of the epithelial and lymphoid components of six thymomas

Six thymomas were classified histologically and studied immunohistochemically with a panel of mouse and rat monoclonal antibodies directed against thymic epithelial and lymphoid components. The antibodies included monoclonal antibodies directed against cytokeratin, medullary epithelial cells (ER-TR5), and HLA-DR and HLA-ABC antigens, as well as antibodies with specificity for thymocytes. Histologically, one thymoma was characterized by epithelial predominance (EP type), two showed lymphoid predominance (LP type), and two showed mixed lymphoid/epithelial composition (MLE type); one thymoma was a malignant pure epithelial thymoma (PE type). In the thymomas of the MLE and EP types the major populations of cells consisted of HLA-DR-negative, cytokeratin-positive epithelial cells with large ER-TR5-positive subpopulations (i.e., the phenotype of medullary epithelium). In the thymomas of the LP type, the neoplastic population was composed of cytokeratin-positive, ER-TR5-negative cells that expressed the HLA-DR antigen (i.e., the phenotype of cortical epithelium). The thymoma of the PE type consisted of cytokeratin-positive cells, some of which were ER-TR5- and HLA-DR-positive. Double immunofluorescence studies revealed the presence of varying numbers of additional nonepithelial (nonlymphoid) HLA-DR-positive cells in thymomas of the LP, MLE, and EP types. The intervening lymphoid population in the thymomas of the LP, MLE, and EP types consisted largely of cortical thymocytes, as defined by immunologic characterization. These results suggest that thymomas can be classified as medullary or cortical epithelial neoplasms on the basis of their immunologic phenotypes.     

Fiber counting and analysis in the diagnosis of asbestos-related disease

Analysis of numbers and types of asbestos fibers present in lung tissue may provide insights into the pathogenesis of asbestos-induced disease, as well as diagnostic information concerning the relationship of a given lesion to asbestos exposure. This type of analysis requires extraction of fibers and asbestos bodies from lung tissue, preferably by means of a digestion-and-concentration technique, and examination with a combination of electron optical techniques, including electron diffraction and energy-dispersive x-ray spectroscopy. The combination permits definitive identification of asbestos fibers. Asbestos bodies have been shown to contain asbestos no matter what population they are found in, but they appear to be of value in ascertaining unusual exposure only when present in very large numbers. Numbers of asbestos bodies markedly underestimate total numbers of fibers present in lung. In patients from the general population, the mean number of asbestos fibers is about 1 X 10(6)/g dry lung; of this number, more than 80 per cent are fibers of chrysotile less than 5 microns long. Patients in the general population who have pleural plaques have about the same total number of fibers, but their lungs contain about a 50-fold increase in long thin amphibole fibers of commercial origin. Patients who have asbestosis and most patients who have mesothelioma have 100 to 200 X 10(6) fibers/g dry lung; the grade of asbestosis appears to be related to total fiber content. Occasional patients may develop mesotheliomas with much smaller fiber burdens. Both benign and malignant pleural diseases appear to be closely related to the presence of long thin amphibole fibers. Analysis of pulmonary fiber burden suggest that asbestos-related disease is not merely a matter of total numbers of fibers present, but that factors such as fiber type and size are equally important.     

Plasma cell granuloma of the thyroid

Plasma cell infiltrates in the thyroid are rare. They may represent several processes, such as localized plasmacytoma, multiple myeloma, or plasma cell granuloma (PCG). It may be difficult to distinguish these disorders on the basis of morphologic features in sections stained with hematoxylin-eosin. All may be composed of mature plasma cells, without admixed macrophages or lymphocytes, that infiltrate the thyroid and adjacent connective tissue. The identification of the uncommon, but benign, PCG is facilitated by immunohistochemical staining to demonstrate an admixture of plasma cells with cytoplasmic kappa and lambda light chains. The polyclonal nature of the plasma cell infiltrate distinguishes PCG from neoplastic plasma cell proliferation.