Image cytophotometric DNA analysis of cystadenolymphomas

Warthin's tumour of the parotid gland is generally a benign lesion, consisting of an epithelial and a lymphoid component with unclear histogenetic relationship, 17 cases of Warthin's tumour were investigated for ploidy related parameters by the image analysis system CAS200. All cases investigated were euploid. A diploid DNA pattern (Auer type I) was detected in 7/17 (41%) cases both in the epithelial and lymphoid component of the same tumour. In addition to a diploid cell fraction a tetraploid cell component was found in 7/17 (41%) cases, coincidentally, in the epithelial and lymphoid component (Auer type II). Euploidy in all investigated cases is in agreement with the generally benign nature of Warthin's tumours. The similarity of the DNA pattern (Auer type) in the genetically unrelated epithelial and lymphoid components in most cases (84%) is suggested to be related to a similar functional state of these two components and is discussed in relation to the histogenesis of cystadenolymphomas.