Serial scrape smear cytology of radiation response in normal and malignant cells of oral cavity.

Serial scrape smears were taken from 111 patients receiving radiotherapy for squamous cell carcinoma of the oral cavity. The surface of the tumour and the normal mucosa on the opposite side was scraped before and after delivery of various fractions of radiotherapy and were evaluated by light microscopy. The number of cells exhibiting changes like multinucleation, micronucleation, nuclear budding, binucleation and cytoplasmic granulation were counted. The results were expressed as abnormality per 1000 cells. Each parameter showed a statistically significant increase with radiation dose in both normal and malignant oral cells. In the normal mucosal cells the mean values after 6Gy and 24Gy respectively were 0.83 and 2.91 (p<0.001) for cells with multinucleation, 1.83 and 4.42 (p<0.001) for micronucleation, 2.58 and 5.15 (p<0.001) for nuclear budding, 5.92 and 12.58 (p<0.001) for binucleation, and 3.67 and 7.17 (p<0.001) for cytoplasmic granulation. On the other hand, in malignant cells, the mean values before and after treatment with 24 Gy respectively, were 3.14 and 7.08 (p<0.001) for cells with multinucleation, 1.05 and 5.97 (p<0.001) for micronucleation, 2.54 and 8.82 (p<0.001) for nuclear budding 7.11 and 27.93 (p<0.001) for binucleation and 5.32 and 12.02 (p<0.001) for cytoplasmic granulation. The study showed that there is a dose-related increase in multinucleation, micronucleation, nuclear budding, binucleation and cytoplasmic granulation after various fractions of radiotherapy in both normal and malignant oral cells, however these changes are more marked in the malignant cells.