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Human Chorionic Gonadotropin in Lung and Lung Tumors. Immunohistochemical Study on Unbalanced Distribution of Subunits. Fukayama, M., Hayashi, Y., Koike, M. et al. Department of Pathology, Tokyo Metropolitan Komagome Hospital, Tokyo, Japan. Lab. Invest. 55: 433-443, 1986.

To demonstrate unbalanced distribu- tion of subunits of human chorionic gonadotropin (hCG) in the lung and lung tumors and to clarify its significance in differentiation and carcinogenesis of the lung, immunohistochemistry was performed on human fetus, infant, and adult lungs, and endocrine and nonendocrine tumors of the lung. Tissues were immunostained for alpha-subunits and for beta-subunits of glycoprotein hormones (hCG, luteinizing hormone, follicle stimulating hormone, and thyroid stimulating hormone), serotonin, and gastrin-releasing peptide. Immunoreactive alpha-subunit was first identified in endocrine-like cells at the 39th gestational week, and was found in all infant lungs and two-thirds of adult lungs. The hCGbeta-immunoreactive cells were extremely rare in an adult lung, and were not found in fetus or infant lungs. The alpha-subunit-containing cells were present in neuroepithelial bodies, tumorlets, carcinoid tumors, and small cell carcinomas of the lung (SCCL). There were occasionally alpha-subunit- containing cells in non-SCCL but one of the carcinomas also contained many serotonin-positive and gastrin-releasing peptide-positive cells in the same region. All alpha-subunit-immunoreactive cells lacked immunoreactivity for beta- subunits of glycoprotein hormones, except some for hCGbeta in one carcinoid tumor. Immunoreactive cells for isolated hCGbeta appeared much more frequently in non-SCCL than in SCCL. Most non-SCCL containing hCGbeta-positive cells did not show alpha-subunit-immunoreactivity. Thus, im- munohistochemical distribution of hCG- subunits was unbalanced and hCG-subunits may be expressed through an independent mechanism, commonly in the lung and lung tumors. The significance of isolated alpha-subunit is further discussed in light of multidirectional differentiation of lung neoplasms (14, 17).

Correlation Between Needle Biopsy of Lung Tumors and Histopathologic Analysis of Resected Specimens. Horrigan, T.P., Bergin, K.T. Division of Cardiothoracic Surgery, Cleveland Metropolitan General Hospital, Case West- ern Reserve University School of Medicine, Cleveland, OH, U.S.A. Chest 90: 638-640, 1986.

Needle aspiration of a pulmonary mass may accurately delineate malignant from nonmalignant pulmonary lesions; however, needle aspiration may be unable to iden- tify a specific cell type. Therefore, a retrospective review of patients undergo- ing needle aspiration of pulmonary masses

was carried out for the years, 1979 through September 1984. A Lee needle was used, which produces a sample of tissue l-mm in diameter suitable for his- topathologic analysis as well as a cytologic specimen. A total of 87 needle biopsies were carried out, but only 46 patients later underwent resection. Five patients (6%) sustained a pneumothorax, and four required a chest tube. Minimal hemoptysis occurred in three patients (3%). Eight patients were subsequently found to have benign lesions, and there were 38 malignant tumors. Seven needle biopsies (18%; 7/38) were nondiagnostic and subsequently proved to be malignant. Thirty-one needle biopsies were diagnos- tic of malignant neoplasms (82%; 31/38). Twenty specimens showed the same cell type as the needle biopsy (65% 20/31). Eleven resected specimens disagreed with the cell type from the needle biopsy (35; 11/31). In these ii patients a change in management was indicated because of the delineation of a different cell type in only four (11% of all 38 patients with cancer). Mixed tumors and small cell car- cinoma provide the area of most concern. Our conclusions are that needle biopsy accurately indicated a malignant neoplasm in 82% of the patients undergoing later resection and that the specimens from Lee needle biopsy accurately predicted the cell type in 65% of the specimens. The inaccurate histologic diagnosis was im- portant clinically in only 11% of the patients. Overall, the needle biopsy of pulmonary lesions provided a correct decision on management in 87% of the cases in which biopsy provided diagnosis of a malignant neoplasm (31 patients).

Periodic Acid-Schiff-Lead Hematoxylin as a Marker for the Endocrine Phenotype in Human Lung Tumors. Hoyt, R.F. Jr., Sorokin, S.P., McDowell, E.M., Trump, B.F. Department of Anatomy, Boston Univeristy School of Medicine, Boston, MA 02118, U.S.A. Arch. Pathol. Lab. Med. ii0: 943-951, 1986.

Periodic acid-Schiff-lead hematoxylin is evaluated for light microscopic diag- nosis of pulmonary endocrine cell tumors. Twenty-eight aldehyde-fixed primary human lung tumors were examined by electron microscopy. Fifteen were classified as endocrine (one carcinoid, six small-cell carcinomas, and an atypical' group of eight with diverse histologies), based on possession of characteristic submicronic, dense-cored cytoplasmic granules. Electron probe analysis in the carcinoid tumor established that dense-cored granules were equivalent to lead hematoxylin-stained granules, which were visible in glycol methacrylate sections as seen on light microscopy. Lead hematoxylin-positive granules were also seen is seven of eight 'atypical' tumors, three small cell carcinomas, a glucagonoma, and a chemodectoma. Findings

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were equivocal in two small cell carcinomas, and negative in all other lung tumors. In overall diagnostic acuity, periodic acid-Schiff-lead hematoxylin equals electron microscopy, surpasses argyrophilia, serotonin fluorescence, and immunolocalization of polypeptide hormones. It is approached only by antineuron-specific enolase immunoreactivity.

Human Lung Tumours May Coexpress Dif- ferent Classes of Intermediate Filaments. Garter, K.C., Dunnill, M.S., Van Muijen, G.N.P., Mason, D.Y. Nuffield Department of Pathology, John Radcliffe Hospital, Oxford OX3 9DU, UK. J. Clin. Pathol. 39: 950-954, 1986.

Ninety four pulmonary neoplasms were examined immunocytochemically with two or three different monoclonal antibodies against the intermediate filament proteins cytokeratin, neurofilament, vimentin, and desmin. In normal tissues these have a different and non- overlapping distribution, and it is generally believed that tumours maintain the same pattern of expression as the tissues from which they arise. In this report, however, the coexpression of at least two (and less commonly three or four) different intermediate filaments was seen in 40% (37 of 94) of the cases of lung cancer. These results, especially if confirmed in other common types of human malignancy, have considerable im- plications for the use of anti- intermediate filament antibodies in diag- nostic pathology.

5. CLINICAL ASSESSMENT

Bronchoscopy. Sanderson, D.R. Division of Thoracic Dis- eases and Internal Medicine, Mayo Clinic and Mayo Foundation, Rochester, MN, U.S.A. Br. Med. Bull. 42: 244-248, 1986.

Bronchoscopy is an essential part of contemporary pulmonary medicine and surgery. Topical anaesthesia is often adequate, although general anaesthesia may be preferred for prolonged examina- tions or in children. Preoperative evaluation of suspected malignancy in- cludes staging and determination of his- tologic cell type. Many diffuse intersti- tial lung diseases are amenable to diag- nosis by transbronchoscopic biopsy of lung parenchyma (TBLB) and bronchoal- veolar lavage (BAL). These techniques are especially effective for evaluating pul- monary infiltrations in immunocompromised patients and may obviate the need for open lung biopsy in some seriously ill patients. Therapeutic application, such as suctioning of retained secretions un- der direct vision, is highly effective in the critical care setting. Palliative therapy of malignant airway obstruction with Nd:YAG laser and brachytherapy are new and important development in broncho- scopic practice.

Mediastinoscopy Trastek, V.F., Piehler, J.M., Pairolero, P.C. Section of Thoracic and Cardiovas- cular Surgery, Department of Surgery, Mayo Clinic and Mayo Foundation, Rochester, MN, U.S.A. Br. Med. Bull. 42: 240-243, 1986.

Mediastinoscopy was first recommended by Carlens in 1959 as an invasive endo- scopic technique to evaluate the mediastinum. It is most frequently used to diagnose mid mediastinal masses and to stage bronchogenic carcinoma. It can be performed with minimal mortality and mor- bidity in the hands of experienced personnel. Controversy still exists whether this procedure should be used routinely or selectively in staging a patient with bronchogenic carcinoma. It has been, and will c~ntinue to be. useful technique in the evaluation of the mediastinum.

Comparative Studies of Computerized Tomography and Mediastinoscopy for the Staging of Bronchogenic Carcinoma. Rhoads, A.C., Thomas, J.H., Hermreck, A.S., Pierce, G.E. Department of Surgery, University of Kansas College of Health Sciences and Medical Center, Kansas City, KS 66103, U.S.A. Am. J. Surg. 152: 587- 590, 1986.

The accuracy of mediastinal com- puterized tomographic scans for the stag- ing of bronchogenic carcinoma varies be- tween institutions. In the present study, the sensitivity rate was 57 percent, the specificity rate 69 percent, and the overall accuracy rate 64 percent, all of which were generally lower than rates reported in the recent literature. Dif- ferent scanning equipment, diagnostic criteria, and patient populations may all contribute to this variance. The data in this report suggest that tumor histologic type and location also influenced the ac- curacy of computerized tomography. On the basis of this study and review of the literature, it is recommended that any given institution assess the accuracy of its own computerized tomographic medias- tinal scans before substituting scanning for mediastinoscopy in the preoperative staging of bronchogenic carcinoma.

Standard and Computed Tomography in the Evaluation of Neoplasms of the Chest: A Comparative Efficacy Assessment. Inouye, S.K., Sox, H.C. Jr. Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, U.S.A. Ann. Intern. Med. 105: 906-924, 1986.

Although in practice computed tomog- raphy (CT) has nearly replaced standard tomography in the evaluation of chest diseases, an analysis of the literature shows that standard tomography may be preferred in some settings. After a detailed review of studies on test performance, we calculated overall sen- sitivity and specificity values. Using Bayesian analysis, we then developed