Table 2

Relation of clinical response to p53 sequencing and immunohistochemical results and to apoptosis in breast cancer patients with neadjuvant treatment

Two treatment regimen with different cytotoxic mechanisms (FEC and paclitaxel) are compared. Sensitivity and specificity of p53 sequencing, p53 IHC, p53 status, and apoptosis to detect responders (CR, PR) and nonresponders (SD, PD) is presented and corresponding confidence intervals are added in brackets.

FECPaclitaxel
CR, PRSD, PDCR, PRSD, PD
p53 sequencingP = 0.0029P = 0.0755
Mutant07Sensitivity100%(84.67; 100)51Sensitivity33.33%(11.8; 61.6)
Normal1810Specificity41.18%(18.44; 67.08)1016Specificity94.10%(71.3; 99.9)
p53 IHCP < 0.0001P = 0.1437
Positive114Sensitivity94.44%(72.71; 99.86)84Sensitivity53.33%(26.6; 78.7)
Negative173Specificity82.35%(56.57; 96.20)713Specificity76.47%(50.1; 93.2)
p53 statusaP < 0.0001P = 0.0118
Positive116Sensitivity94.44%(72.71; 99.86)114Sensitivity73.33%(44.9; 92.2)
Negative171Specificity94.12%(71.31; 99.86)413Specificity76.47%(50.1; 93.2)
ApoptosisbP < 0.0001 c d P = 0.0058
Positive170Sensitivity94.44%(72.71; 99.86)07Sensitivity100%(79.4; 100)
Negative117Specificity100%(83.84; 100)137Specificity50.00%(23.0; 77.0)
  • a The p53 status represents the combination of results from p53 sequencing and IHC. The p53 status is positive in tumors with either p53 gene mutation or positive immunohistochemical staining or both. The p53 status is negative when both parameters are normal (normal p53 gene and negative staining).

  • b Apoptosis results were dichotomized for correlation with clinical response (see “Statistical Analyses”). All Ps were calculated with a two-sided Fisher’s exact test. Apoptosis assay was done for a total of 27 of 32 patients of the paclitaxel group; five were missing.

  • c two in the responder group and

  • d three in the nonresponder group.