Morphologic and clinical determinants of response to therapy in small cell carcinoma of the lung

Value of adequate fixation for accurate histological interpretation

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Immunophenotype of multinucleated cells in giant cell lesions

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Prognostic significance of nuclear DNA content in small cell carcinoma of the lung

The relationship between the nuclear DNA histogram patterns of tumor cells obtained by brushing via bronchoscopy and the survival time of 39 patients with small cell carcinoma of the lung was investigated. The brushing smears were stained by a modified Feulgen method. The nuclear DNA content was measured at 550 nm using a microspectrophotometer. The DNA histogram pattern was classified into type I, which contained a higher proportion of G0G1-phase cells, and type II, which contained a higher proportion of S, G2M-phase cells. The median survival times for the patients with limited disease of type I, type II and the patients with extensive disease of type I, type II were 17.2 months, 10.2 months, 10.0 months, and 5.6 months, respectively. Patients with limited disease of type I had a significantly longer survival time than patients with limited disease of type II. A distinct correlation was found between the histogram pattern and the survival of the patients. These results indicated that the nuclear DNA histogram pattern may be an indicator to allow speculation as to the prognosis of patients with small cell carcinoma of the lung.

Neural markers in carcinoma of the lung

Small cell carcinoma (SCC) is considered to be of neuroendocrine origin. Neurone specific enolase (NSE) and PGP 9.5 are markers of neural and neuroendocrine differentiation. S-100 protein is a marker of glial differentiation. The expression of these markers in endobronchial biopsy and lung tumour resection specimens was studied to see if any diagnostic, prognostic or therapeutic implications would emerge. Zamboni fixed endobronchial tumour biopsy specimens from 20 patients were examined. Twelve of these were cases of SCC and 8 were non-SCC. Of the 12 SCC, 7 were positive for NSE, 6 for PGP 9.5 and 5 for S-100 protein. Cases which showed a positive reaction for NSE had a mean survival of 9.1 months compared with 3.9 months for those with a negative reaction, but the number of cases is too small to assign any statistical significance. There was no difference in survival times between positive and negative reactors for PGP 9.5 and S-100 protein. All 8 cases of non-SCC showed positive reactions to all three markers. Of 32 formalin fixed lung tumour resection specimens 6 were cases of SCC, 25 non-SCC and 1 a chemodectoma. Three of the 6 cases of SCC showed positive staining for NSE, 3 for PGP 9.5 and 1 for S-100 protein. Of the 25 non-SCC, 10 were positive for NSE, 12 for PGP 9.5 and 6 for S-100 protein. The 1 chemodectoma stained positively for all three markers. Neuroendocrine markers are of little value in differentiating SCC from non-SCC. Positive staining for NSE in SCC may be an indicator of prolonged survival but further investigation is required.