Flow cytometric analysis of DNA content in parotid tumor and its contiguous acini.

To investigate the relationship between proliferative capacity of salivary gland cells in contiguous acini of parotid tumors and recurrent neoplasma, DNA contents of 30 fresh specimens of parotid were studied by using cytometry in tumors, normal and shallow or deep lobe acini of the masses. The results showed that the DI was 1.369, S% 16.95, PI 26.18 in malignant tumors; DI was 1.171, S% 12.41, PI 15.54 in recurrent pleomorphic adenoma; DI was 1.141, S% 12. 74, PI 13.07 in pleomorphic adenoma, DI was 0.999, S% 5.10, PI 8.00 in normal acini. Analysis of variance showed there was a significant difference (P < 0.01). The average DNA contents of shallow on deep lobe of contiguous tumors was 1.08 in DI, 10.65 in S%, 13.49 in PI in malignant tumor, 1.06 in DI, 8.96 in S% and 9.85 in PI in pleomorphic adenoma, which were all higher than in normal acini (P > 0.05). It was concluded that the levels of DI and S% of parotid tumor and its contiguous acini are related to degree of malignancy or recurrent condition of the tumors, suggesting contiguous acini of parotid tumors had the strong capacity of proliferation, which might play an important role in recurrent or malignant change of the parotid tumors.