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Detection of a Ganglioside Antigen As- sociated With Small Cell Lung Carcinomas Using Monoclonal Antibodies Directed Against Fucosyl-GMl. Nilsson, O., Brezicka, F.T., Holmgren, J. et al. Department of Psychiatry and Neurochemistry, University of Goteborg, S-413 46 Goteborg, Sweden. Cancer Res. 46: 1403-1407, 1986.

Monoclonal antibodies with an ap- parent specificity for fucosyl-GMl (Fuc- GMI) were produced by the immunization of

mice with Fuc-GMI adsorbed to Salmonella minnesota bacteria and fusion of the spleen cells with the myeloma cell line Sp 2/0. The antibodies detected Fuc-GMI with a unique ceramide composition con- taining 2-hydroxy fatty acids in ii of 12 cases of small cell carcinoma of the lung. Trace amounts of Fuc-GMI were detected in 1 of ii squamous epithelial cell lung carcinomas. Fuc-GMI was also detected in 1 of 7 pancreas carcinomas but was not detected in any of the other cancers analyzed. Small amounts of Fuc- GMI without 2-hydroxy fatty acids were detected in normal adult pancreas, spleen, and brain but could not be detected in normal lung tissue. Fuc-GMI with 2-hydroxy fatty acids is suggested to be a specific ganglioside associated with small lung carcinomas. The monoclonal antibodies directed against Fuc-GMI may be useful for specific im- munodiagnosis of small cell lung car- cinomas and might also be useful for specific immunotherapy of these malignant tumors.

The 'Grey Area' Between Small Cell and Non-Small Cell Lung Carcinomas. Light and Electron Microscopy Versus Clinical Data in 14 Cases. Mooi, W.J., Van Zandwijk, N., Dingmans, K. et al. Department of Pathology, Academic Medical Centre, 1105 AZ Amsterdam, Netherlands. J. Pathol. 149: 49-54, 1986.

we studied 14 lung tumours which on light microscopy had posed difficulties on classification as either small cell or non-small cell carcinomas. The light and electron microscopical features were com- pared with patient follow-up data. Electron microscopy showed neuroendocrine granules in 12 cases, and adeno- and squamous cell differentiation but no neuroendocrine granules in the remaining two cases. The latter two cases showed prolonged patient survival (both patients alive after 2.5 and 2 years, respectively). Ten of the cases with neuroendocrine granules showed a rapid course of disease (death between 2.5 weeks and 15 months after diagnosis) and marked initial response to multiagent chemotherapy. Thus, the clinical impres- sion of these cases was that of small cell carcinoma. The remaining two cases with neuroendocrine granules showed a more protracted course, with death after

1.5 and 2.5 years. These two tumours did not show the light microscopical features of atypical carcinoid. The results il- lustrate the value of electron microscopy in predicting clinical behaviour of car- cinomas difficult to palce into small cell or non-small cell carcinoma groups. They also point to the existence of neuroendocrine carcinomas other than car- cinoids with a more protracted course than small cell carcinomas.

Papillary Adenocarcinoma of Lung With Psammoma Bodies: Report of a Case Derived From Type II Pneumocytes. Salisbury, J.R., Darby, A.J., Whimster, W.F. Department of Morbid Anatomy, King's College Hospital, London SE5 8RX, UK. Histopathology I0: 877-884, 1986.

A 52-year-old woman underwent thoracotomy for the removal of a mass in the middle lobe of the right lung. Light microscopy showed a tumour with the mor- phology of a papillary adenocarcinoma with numerous psammoma bodies. Electron microscopy revealed the tumour cells to possess the lamellated intracytoplasmic inclusions characteristic of normal and neoplastic type II pneumocytes. Psammoma bodies have not previously been reported in type II cell carcinoma of the lung. Alveolar cell carcinoma should be con- sidered in the differential diagnosis of a papillary adenocarcinoma with psammoma bodies occurring in the lung.

Mucin-Producing Bronchioalveolar-Cell Carcinoma. With Special Reference to a Characteristic Structure Revealed by Phosphotungstic Acid-Hematoxylin Staining. Ebihara, Y., Sagawa, H. Department of Pathology, Toho University School of Medicine, Tokyo, Japan. Acta Cytol. 30: 643-647, 1986.

In four cases of bronchioloalveolar- cell carcinoma of the mucin-producing type, the cells were characterized electron microscopically by cored microvilli seen on the free surface of the tumor cells, structures that cor- responded well to the phosphotungstic acid-hematoxylin (PTAH) stained struc- tures seen by light microscopy in his- tologic specimens. The exfoliative cytol- ogy specimens contained corresponding PTAH-stained structures on the cell surfaces, namely, a prominent cell membrane with a 'beaded' or 'peglike' configuration and, in places, a 'featheray' nature, findings quite dis- similar to the surfaces of other well- differentiated adenocarcinoma cells. The cytologic specimens also exhibited characteristic nuclear indentations and tightly connected cell groupings. These results indicate the existence of a tzpe of bronchioloalveolar-cell carcinoma not derived from type II alveolar epithelial cells or Clara cells.