RESUMEN
The literature on breast cancer reports conflicting prognostic results with respect to DNA ploidy of flow cytometric DNA histograms. This might result from different DNA ploidy classification methods. Our study evaluated the prognostic power of DNA ploidy, using different classification methods, in a large prospective group (n = 1301) of breast cancer patients. Flow cytometric DNA histograms obtained from fresh frozen material were interpreted with use of a commercially available computer program. On the basis of the number of stemlines and the DNA Index, we classified the DNA ploidy by different methods. In all of the cases, the classification method "DNA diploid versus DNA nondiploid" provided the best prognostic significance for overall survival (OS) (Mantel-Cox (MC) = 5.4, P = .02; relative risk (RR) = 1.3, P = .05) and for disease-free survival (DFS) (MC = 11.8, P = .0006; RR = 1.3, P < .05). This was also true for the OS of the lymph node-positive (but not the lymph node-negative) subgroup (MC = 4.1, P = .04; RR = 1.3, P = .05). In subgroups classified on the basis of tumor size, DNA ploidy showed prognostic significance for DFS only in the subgroup of tumors smaller than 2 cm and larger than 5 cm. In multivariate analysis, DNA ploidy showed no additional prognostic power to lymph node status and tumor size. The classification "DNA diploid versus DNA nondiploid" was mostly consistent with respect to prognostic power for OS and DFS, especially in small or lymph node-positive tumors. The RR of DNA nondiploid patients was only marginally higher, however, so large study groups are required to reach statistical significance. This could partly explain the disagreements in the literature. Therefore, DNA ploidy seems to be of little clinical importance in breast cancer patients, compared with other prognostic parameters.
Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Ploidias , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/mortalidad , Citometría de Flujo , Humanos , Ganglios Linfáticos/patología , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Tasa de SupervivenciaRESUMEN
Conflicting prognostic results with regard to DNA flow cytometric cell cycle variables have been reported for breast cancer patients. An important reason for this may be related to differences in the interpretation of DNA histograms. Several computer programs based on different cell cycle fitting models are available resulting in significant variations in percent S-phase and other cell cycle variables. Our present study evaluated the prognostic value of percent S-phase cells obtained using 5 different cell cycle analysis models. Flow cytometric DNA histograms obtained from 1,301 fresh frozen breast cancer samples were interpreted with 5 different cell cycle analysis models using a commercially available computer program. Model 1 used the zero order S-phase calculation and "sliced nuclei" debris correction, model 2 added fixed G2/M- to G0/G1-phase ratio, and model 3 added correction for aggregates. Model 4 applied the first-order S-phase calculation and sliced debris correction. Model 5 fixed the coefficients of variation CVs of the G0/G1- and G2/M-phases in addition to applying the sliced nuclei debris correction and zero order S-phase calculation. The different models yielded clearly different prognostic results. The average percent S-phase cells of the aggregate correction model (model 3) provided the best prognostic value in all cases for overall survival (OS) as well as disease-free survival (DFS) (OS: p < 0.0001; DFS: p < 0.0001), in lymph node-positive cases (OS: p < 0.0001; DFS: p = 0.004) and in DNA-diploid subgroups (OS: p = 0.004; DFS: p = 0.001). For the lymph node negative and DNA-non-diploid subgroups, the percent S-phase of the second cell cycle reached slightly better prognostic significance than the average percent S-phase cells. In multivariate analysis, the average percent S-phase of the aggregate correction model had the best additional prognostic value to tumor size and lymph node status. In conclusion, different cell cycle analysis models yield clearly different prognostic results for invasive breast cancer patients. The most important prognostic percent S-phase variable was the average percent S-phase cells when aggregate correction was included in cell cycle analysis.
Asunto(s)
Neoplasias de la Mama/patología , ADN de Neoplasias/análisis , Fase S , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/genética , Neoplasias de la Mama/mortalidad , Femenino , Citometría de Flujo , Humanos , Metástasis Linfática , Persona de Mediana Edad , Pronóstico , Análisis de SupervivenciaRESUMEN
A previously healthy 10-year-old boy died a few days after onset of septicaemia with non-specific clinical symptoms. Influenza B virus was isolated post mortem from pulmonary tissue. The histopathological findings did not indicate a virus disease. Specimens were taken for virus culture from other people in contact with the patient and affected with influenza-like illnesses. One other strain of influenza B virus was isolated. The strains could not be distinguished either serologically or genetically from other influenza B isolates of the season 1992/'93.