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Background. Although flow cytometry (FCM) has become a widely used technique for the measurement of DNA content in solid tumors, the correlation of ploidy analysis by FCM with cytogenetic analysis (CGA) is not well described. The sensitivities of G-banded CGA and FCM were compared to determine the accuracy of the DNA index value (DI) as a measurement of chromosome number. Methods. Tumor specimens from 56 pediatric cases were analyzed for DNA content by both FCM and CGA. Nuclei for FCM were prepared from archival tissue in 53 specimens using a modification of the Hedley technique and from fresh tissue in 3 specimens. Metaphase chromosomes for CGA were prepared from standard solid tumor harvests and Giemsa-trypsin banding procedures. Ploidy status for this study was defined as (1) diploid--DI between 0.97 and 1.03 by FCM or chromosome number [+ or -] 2 from normal by CGA (44-48); and (2) aneuploid--DI < 0.97 or > 1.03 by FCM or total chromosomes < 44 or > 48 by CGA. Results. Forty-nine of the 56 pediatric specimens were evaluable by both techniques. Concordance was observed in 34 cases (69%) between the two techniques in assigning similar ploidy status to a tumor (22 diploid and 12 aneuploid). It also was observed that among the aneuploid concordant cases, the actual DI obtained from archival material could predict total chromosome number with 95% accuracy. The 15 discordant cases showed a distinct aneuploid population by FCM, but were diploid by CGA. Conclusions. A correlation of 69% was obtained between both techniques to assign a similar pleidy status (diploid versus aneuploid) in 56 pediatric solid tumors. These results support the combined use of CGA and FCM to obtain the most complete analysis of DNA content and chromosome abnormalities in pediatric solid tumors. FCM on formalin-fixed, paraffin-embedded tissue can be used to measure total DNA content. Cancer 1993; 72:2033-41.

Background. The prognostic value of flow cytometric DNA analysis on paraffin-embedded tumor samples has been controversial in esophageal cancer. To clarify its true significance, the authors developed an improved method that excludes the possibility of contamination by lymphocytes in tumor sample. Methods. Single nuclear suspension was prepared from paraffin-embedded samples on 103 patients with squamous cell carcinoma of the esophagus. Both DNA content and nuclear size were simultaneously measured by flow cytometry on 30,000 nuclei, and contaminated lymphocyte nuclei were eliminated from the data by optimal gating. Correlation between DNA ploidy and postoperative survival was examined. Results. Analysis using a flow cytometric cell sorter showed that the frequency of tumor cells in the lymphocyte-reducing gating fraction (LGF) was significantly higher than that in the conventional nongating fraction (NGF). LGF analysis showed aneuploid peaks in 58 patients (56.3%), but NGF analysis showed aneuploid peaks in only 38 patients. LGF analysis revealed that the aneuploid tumors had higher histologic grading (P < 0.05) and worse survival rate (P < 0.01) compared with diploid tumors. However, conventional methods could not detect this difference. Conclusions. Flow cytometric analysis gating by nuclear size may be helpful to detect aneuploid peaks, and for predicting prognosis of patients with squamous cell carcinoma of esophagus. Cancer 1993; 72:1813-8.

Background. DNA ploidy and S-phase fraction measured by DNA flow cytometry were shown to correlate with several clinicopathologic characteristics in several types of tumors. Methods. DNA flow cytometry was performed on 329 samples (164 normal mucosa, 165 tumors) obtained from 165 patients (112 men) with stomach cancer, and the findings were correlated with various clinicopathologic characteristics of the patients in a prospective manner. Results. Seventy-nine of 165 samples (48%) from the tumors gave an aneuploid histogram. None of 164 samples from the normal mucosa showed aneuploidy. There was no significant difference in the frequency of DNA aneuploidy in terms of age, sex, symptom duration, bleeding history, gastric outlet obstruction, weight loss, performance status, serum hemoglobin level, albumin level, creatinine level, tumor size, tumor location in the stomach, and TNM stage. Moderately well differentiated tumors had a significantly higher frequency of aneuploidy compared to well differentiated or undifferentiated tumors. S-phase fraction was obtained in 162 of 164 samples from the normal mucosa, and 123 of 165 samples from the tumors. The overall mean of the S-phase fraction was 4.01% (range, 0.5-23.6%) for the normal mucosa and 13.8% (range, 0-51.9%) for the tumors. Higher S-phase fraction of tumors was correlated with history of weight loss, poorer performance status, and histologically less differentiated tumors. Conclusions. The overall frequency of aneuploidy was 48% in stomach cancer. DNA aneuploidy showed significant correlation with histologic differentiation of tumors. S-phase fraction of the tumors showed significant correlartion with history of weight loss, performance status of the patients, and histologic differentiation of tumors. Cancer 1993; 72:1819-26.

Background. The prognostic value of flow cytometric analysis of DNA content is contradictory in renal cell carcinoma (RCC). Methods. Flow cytometric analysis was performed on 72 patients with RCC, and the relationship between the DNA content and pathologic or clinical features was investigated. Results. Aneuploidy was observed in 36 (50%) of these patients. Two tissue samples from primary tumors of 12 patients were analyzed, and heterogeneity was found in 7 (58%) of these patients. The incidence of aneuploidy was significantly higher in high-grade than in low-grade tumors (P = 0.0328). All five tumors with a maximum diameter of 2.5 cm or smaller (T1N0M0) were diploid, and a trend for more aneuploid tumors among high-stage diseases was observed. The survival rate of patients with diploid tumors was not significantly different from that of those with aneuploid tumors in the low-or high-stage group. Conclusions. DNA ploidy assessed with one sample is not a prognostic factor, and heterogeneity between different samples of a given tumor indicates that one sample is not enough for DNA flow cytometry in RCC. Cancer 1993; 72:1319-23.

Background. Although it is important to determine any relationship between tumor DNA ploidy and its biologic behavior, the correlation between DNA-ploidy and the prognosis of patients with ovarian cancer is not conclusive. Accordingly, the authors evaluated the clinical application of DNA ploidy in ovarian cancer. Methods. Flow cytometric measurements were performed in 45 selected patients with well-differentiated serous cystadenocarcinoma of the ovary, Stages Ic-IV. All of them had the same surgical procedure, with retroperitoneal lymphadenectomy including paraaortic nodes, followed by the same postoperative chemotherapeutic regimen. Results. Of the 45 ovarian cancers, 28 were diploid and 17 were aneuploid. The 2-year survival rate and the estimated 5-year survival rate for patients with diploid tumors were significantly greater than those for patients with aneuploid tumors (73.2% versus 46.7% and 29.1% versus 22.4%, respectively). The 2-year survival rate in patients with advanced disease (Stage III or IV) was also significantly higher for those with diploid tumors (53.3% versus 37.4%, respectively), but the estimated 5-year survival rate was similar in both groups (8.9% versus 9.1%, respectively). Patients with advanced disease had aneuploid tumors more frequently than those with early-stage disease. A significantly higher incidence of retroperitoneal lymph node metastasis was observed in aneuploid tumors than in diploid tumors (43.8% in diploid tumors versus 86.7% in aneuploid tumors). The authors found no difference in the response to chemotherapy between diploid and aneuploid tumors. Conclusions. Although tumor DNA ploidy was not as reliable as conventional parameters such as surgical stage in establishing prognosis, it may provide an indicator of lymph node involvement.

Background. The prognostic significance of tumor DNA ploidy in patients with cancer of the pancreas has not been defined because conflicting results have been reported. Methods. DNA content was measured in 56 ductal adenocarcinomas of the pancreas. DNA ploidy status was evaluated by flow cytometry in nuclei isolated from paraffin-embedded tumor tissues. Results. An abnormal DNA stemline was observed in 27 (48%) patients. The percentage of aneuploid tumors was significantly increased in tumors classified as Stage III/IV (53%) compared with those classified as Stage I (22%). A borderline significant association existed between DNA ploidy and radicality of surgery (P = 0.08). The median survival of patients with diploid carcinomas was 6.9 months (standard error, [+ or -] 0.9) in comparison to 4.5 [+ or -] 1.2 months for patients with aneuploid tumors (P = 0.013 by generalized Wilcoxon test; P = 0.023 by generalized Savage test). Although a selection bias cannot be excluded, survival of patients with a radical resection was longer than that of patients with a nonradical resection (P = 0.0008 and P = 0.0085, respectively). In addition, presence of distant metastasis (P = 0.0006 [Wilcoxon test] and P = 0.033 [Savage test]) could be identified as a prognostic factor. In a Cox regression model, results of surgery and DNA ploidy were independent prognostic variables. Conclusions. Because DNA ploidy has a significant impact on prognosis in pancreatic cancer, it should be used as a variable for stratified randomization of patients in therapeutic trials.

Tumor nuclear DNA content was determined by flow cytometry in routinely prepared paraffin blocks from 25 primary malignant melanomas of the extremities. Twelve of the tumors were aneuploid, and 13 were euploid. In this series the presence of aneuploidy appeared to have no prognostic value. Cancer 1992; 70:109-113.

Flow cytometric nuclear DNA analysis was performed on paraffin-embedded tissue samples taken from 184 patients with pheochromocytoma and paraganglioma treated between 1960 and 1987. The Hedley technique was used for measurement of nuclear DNA content. Thirty-five percent of the tumors were DNA diploid, 33% showed a DNA tetraploid pattern, and 32% had DNA aneuploid pattern. Familial pheochromocytoma and associated endocrine or neoplastic disorders were more common among patients with DNA nondiploid tumors. Eighty-four percent of the tumors that invaded blood vessels and all patients with regional or distant metastases had tumors classified as DNA tetraploid or DNA aneuploid. Of 22 patients who had disease progression, 21 (95%) had tumors with abnormal DNA ploidy pattern (P < 0.001). All 12 patients who died of cancer-related disease had abnormal DNA ploidy; none of the patients with DNA diploid tumor (n = 64) have died of pheochromocytoma (P < 0.01). These results suggest that nuclear DNA ploidy pattern is an important and independent prognostic variable for patients with pheochromocytoma and paraganglioma. Cancer 1992; 69:2683-2687

The authors undertook a prospective, flow cytometric study of nuclear DNA ploidy in 140 fresh ovarian tumors. There were 43 benign tumors, 27 borderline tumors, and 70 malignant tumors. Results of DNA ploidy analysis were compared to age at diagnosis, menopausal status, tumor size, histologic type, grade, and International Federation of Gynecology and Obstetrics (FIGO) stage. Although the majority of benign tumor were diploid, 19% were aneuploid. Among the benign tumors, DNA ploidy was significantly associated with tumor type and tumor size. All borderline tumors were diploid. Of the 70 malignant tumors, 64% were aneuploid. In the malignant tumors, DNA aneuploidy has significant univariate associations with histologic type, grade, and FIGO stage. By multivariate analysis, DNA aneuploidy remained significantly associated with stage and grade, both known predictors of survival in ovarian cancer. These results indicate that DNA ploidy varies with the aggressive potential of an ovarian cancer and may, at the time of initial diagnosis, provide additional information about tumor prognosis. Cancer 1992; 69:2668-2675.