DNA-content, inflammatory tissue response and tumour size in human lung carcinoma.

Tumour imprints of 75 resection specimens with human lung carcinoma (lobe and lungs) were fixed with alcohol and Feulgen-stained. Resection specimens were cut into serial sections 6 mm thick and tumour mass, tumour involvement into intrapulmonary and extrapulmonary lymph nodes, detailed pTN-stage were determined. DNA-content, DNA-index, percentage of diploid/hyperploid tumour cells, and morphometric nuclear features were measured using an automated image analyzing system (VISIAC). Only 10% of the measured carcinomas were diploid. The DNA-index showed the broadest variance in large cell anaplastic carcinoma (1.2-3.3). Carcinomas growing predominantly within the alveolar space, i.e. without destroying the interstitial tissue showed a lower DNA-content above 3c and above 5c compared to carcinomas destroying the interstitial tissue. Carcinomas with severe stroma reaction were found to have 33%-48% of DNA above the 3c value whereas carcinomas without stromal reaction had a percentage above 3c ranging 46%-64% (confidence limits, p less than 0.05). DNA-index increases with increasing tumour volume and decreases for large tumours (greater than 100 ccm). Hyperploid and polyploid tumours were found more frequently in case of pT2 and pT3-stages compared to pT1-stages. No relation of DNA-content or ploidy was found to lymph node involvement and inflammatory response of host tissue.