CONCURRENT CYTOGENETIC, INTERPHASE FLUORESCENCE IN-SITU HYBRIDIZATIONAND DNA FLOW CYTOMETRIC ANALYSES OF A CARCINOMA EX-PLEOMORPHIC ADENOMA OF PAROTID-GLAND

We report the cytogenetic, fluorescence in situ hybridization (FISH), and DNA ploidy analyses of a high grade carcinoma ex-pleomorphic adeno ma of the submandibular gland. Our overall combined analyses showed a marked DNA aneuploidy and numerical abnormalities involving all chromo somes. Cytogenetic analysis revealed a near tetraploid modal chromosom al number with tetraploid loss Of chromosomes Y, 1, 6, 9, 11, 14, 15, 17, and 19-21 and hypertetraploid gain of chromosomes 7, 8, and 22, Th e structural abnormalities included der(1;14)(q10;q10),del(6)(q15q34), +del(6)(q15q34), +der(8) 14)(p11.2),i(20)(q10),der(21)t(8;21)(q11.2;q 22.3), +der(21)t(8;21) (q11.2;q22.3). Interphase FISH of the primary a nd short-term cultured cells using directly labeled pericentromeric pr obes for chromosomes 6-12, 17, 18, and Y resulted in alterations corre sponding to the cytogenetic findings. DNA ploidy analysis of both the primary and cultured tumor cells showed a hyperdiploid stemline with D NA indices of 2.6. The results indicate that: (1) marked numerical, st ructural chromosomal, and DNA content abnormalities are present in thi s tumor: and (2) alteration at 8q and 6q regions, together with previo us results, suggest an association between these events and the develo pment and/or progression of this tumor. (C) Elsevier Science Inc., 199 8.