Flow cytometric and image analyses of colorectal adenocarcinomas. A comparative study with clinical correlations.
ABSTRACT Quantitative DNA measurements were performed in 183 colorectal carcinomas by image and flow cytometric analyses of paraffin-embedded tissue. Flow cytometric analysis yielded more diploid tumors compared with image analysis, which identified more tetraploid tumors. Histogram patterns were concordant in 115 tumors (66%); the discordant cases were primarily tumors interpreted as diploid by flow cytometric analysis but were aneuploid or tetraploid by image analysis. Linear regression analysis of DNA indices of concordant samples showed good correlation but only moderate correlation for the entire group. Both techniques revealed more aneuploid tumors in the distal colon and rectum than in the proximal colon. Diploid tumors were associated with a better prognosis; however, tetraploid tumors behaved like aneuploid tumors by flow cytometric analysis but like diploid tumors by image analysis. When stratified by stage, the prognostic value of diploid tumors was seen in stages A and B disease by image analysis only and in stage C disease by flow cytometric analysis only, possibly because of the small cohort size. The S-phase fraction (mean value, 16.8% +/- 9.9%) was higher in aneuploid than in diploid tumors, but no relationship to prognosis was seen. Flow cytometric and image analyses are useful to study ploidy of colorectal carcinoma from archival material. However, important discordant observations reflecting differences in characteristics of the two techniques should be considered, depending on which technique is used.
SourceAvailable from: Luigi Cavazzini[Show abstract] [Hide abstract]
ABSTRACT: BACKGROUND The prognostic value of flow cytometric DNA ploidy in colorectal carcinoma has not been defined clearly. Most previous studies were conducted retrospectively using archival formalin fixed, paraffin embedded tumor samples. Conversely, few data on prospective studies employing fresh or frozen tissue specimens are available. There is general agreement that fresh/frozen material is more reliable than paraffin embedded tissue for DNA ploidy analysis by flow cytometry.METHODS In the current investigation we evaluated the prognostic significance of nuclear DNA content in a prospective series of 191 patients with curatively resected TNM Stage II (n = 107) or Stage III (n = 84) sporadic colon carcinomas. DNA ploidy status was assessed by flow cytometry utilizing multiple frozen tumor samples. Mean follow-up in surviving patients was 48.5 months (median, 46.9 months; range, 29-77 months). The Cox proportional hazards model was used to adjust for several clinical and pathologic covariates.RESULTSOf the 191 carcinomas examined, 47 (24.6%) were classified as DNA diploid and 144 (75.4%) as DNA aneuploid. DNA ploidy pattern was significantly related to tumor site (P < 0.0001), histologic type (P = 0.0002), and grade of differentiation (P = 0.009), but not to other clinical and pathologic variables. Patients with DNA diploid tumors showed a better disease free (P = 0.013) and overall survival (P = 0.021) than patients with DNA aneuploid adenocarcinomas. In particular, patients with Stage II DNA diploid tumors (n = 30) had an excellent clinical outcome, with an overall 5-year survival rate of 97%. When patients were analyzed according to the anatomic site of the tumor, a significant relationship between DNA ploidy status and disease free and overall survival was observed in the group of patients with carcinomas of the proximal colon (n = 84) (P = 0.004 and P = 0.002, respectively), but not among patients whose tumors were sited distally to the splenic flexure (n = 107). In multivariate analysis, nuclear DNA content was demonstrated to be an independent prognostic variable for both disease free and overall survival. Furthermore, in the group of patients with tumors of the proximal colon, DNA ploidy pattern was the single most important prognostic factor.CONCLUSIONS Our results confirm that flow cytometric DNA ploidy status is a significant and independent prognostic factor in patients with colon carcinoma. These findings may have clinical implications for the management of affected patients, especially those with Stage II disease. Cancer 1998;82:49-59. © 1998 American Cancer Society.Cancer 01/1998; 82(1):49 - 59. DOI:10.1002/(SICI)1097-0142(19980101)82:1<49::AID-CNCR6>3.0.CO;2-F · 4.90 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Molar enthalpies of sublimation of 1,2,4-, 1,2,3-, and 1,3,5-tri-hydroxy-benzene, were obtained from the temperature dependence of the vapor pressure measured by the transpiration method. The molar enthalpies of fusion and molar heat capacities of these compounds were measured by DSC. The measured data sets of vaporization, sublimation and fusion enthalpies were checked for internal consistency. Strength of the inter- and intra-molecular hydrogen bonding in di- and tri-hydroxy-benzenes have been assessed.Thermochimica Acta 06/2004; 415:35-42. DOI:10.1016/j.tca.2003.09.011 · 2.11 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Background and Objectives Parameters that allow prediction of the disease course in colorectal cancer would aid the development of improved treatment strategies. For this reason, we evaluated the prognostic value of flow cytometric DNA ploidy and S-phase fraction (SPF) and P-glycoprotein (Pgp) expression in this type of tumor.Methods The prognostic significance of DNA ploidy, SPF, and Pgp expression on paraffin-embedded sections from 107 patients with colorectal carcinoma was determined. The mean follow-up was 36.6 months (range = 3–72 months). DNA ploidy and SPF were evaluated by flow cytometry and Pgp by immunohistochemistry using monoclonal antibody C219. The Cox regression model was used to adjust for several clinical and pathologic covariates.ResultsOf the 107 carcinomas examined, 44 (41.1%) were classified as DNA diploid and 63 (58.9%) as DNA aneuploid. DNA ploidy pattern was significantly related to tumor site (P = 0.010), tumor stage (P = 0.016), and vascular invasion (P = 0.015) but not to other clinicopathologic variables. Patients with DNA diploid tumors showed a better survival rate than did those with aneuploid tumors. After stage IV disease was excluded, patients with diploid tumors also presented a better disease-free and overall survival than did patients with aneuploid tumors. Mean SPF of the whole series was 13.5% (median = 11.3%, range = 1.4%–29.9%). Aneuploid tumors had a higher median SPF than did diploid tumors (17 vs. 6.2; P = 0.0001). SPF was only related significantly with tumor location (P = 0.026). In the multivariate analysis, SPF was a significant independent prognostic factor for overall survival (P = 0.01). When stage IV was excluded, SPF was also an independent prognostic variable for both disease-free (P = 0.02) and overall (P = 0.01) survival. Of 107 tumors, 61 (57%) were positive for Pgp expression, but no relation was found between this and other clinicopathologic parameters. Pgp expression had no influence on survival.Conclusions Our results suggest that flow cytometric DNA ploidy and SPF are significant and independent prognostic factors in patients with colorectal carcinoma, whereas Pgp expression is not. J. Surg. Oncol. 1999;72:167–174. © 1999 Wiley-Liss, Inc.Journal of Surgical Oncology 11/1999; 72(3):167 - 174. DOI:10.1002/(SICI)1096-9098(199911)72:3<167::AID-JSO10>3.0.CO;2-H · 2.84 Impact Factor