Flow cytometric DNA analysis with use of normal lymph node cells as an internal reference standard in ovarian cancer

Fresh frozen and paraffin-embedded tumor specimens of 21 patients with ovarian cancer were investigated by means of flow cytometry. In 4 patients, the fresh frozen tumor specimens (fresh tumor specimens) of ovarian tumors were measured for the DNA ploidy and index. We used the paraffin-embedded normal lymph node tissue specimens which were acquired from retroperitoneal lymphadenectomy as the internal reference standard (IS). In all 21 patients, the paraffin-embedded tumor specimens mixed with a lymph node specimen as an IS (tumor specimen with IS) were measured. In addition, all 21 paraffin-embedded tumor specimens without a lymph node tissue specimen (tumor specimens without IS) were measured. In 4 cases which were measured with the fresh tumor specimens, all 4 tumor specimens with IS had the same patterns of DNA ploidy as the fresh tumor specimens. Of 21 patients, 6 patients showed different DNA ploidy patterns between the tumor specimens with and without IS. Furthermore, all of these 6 patients showed diploidy in the tumor specimens without IS while showing aneuploidy in the tumor specimens with IS. Fourteen (66.7%) of 21 tumor specimens with IS were aneuploidy despite aneuploidy of only 8 (38.1%) tumor specimens without IS. All 4 patients with stage I had diploidy in the tumor specimens with IS, and 13 (81.3%) of 16 patients with stage III or IV had aneuploidy. All 8 patients with diploidy in the tumor specimens with IS had survived for 1-2 years.(ABSTRACT TRUNCATED AT 250 WORDS)