Technetium-99m-sestamethoxyisobutylisonitrile scan as a predictor of chemotherapy response in malignant lymphomas compared with P-glycoprotein expression, multidrug resistance-related protein expression and other prognosis factors
Ch. Kao et al., Technetium-99m-sestamethoxyisobutylisonitrile scan as a predictor of chemotherapy response in malignant lymphomas compared with P-glycoprotein expression, multidrug resistance-related protein expression and other prognosis factors, BR J HAEM, 113(2), 2001, pp. 369-374
The purpose of the present study was to predict the response of malignant l
ymphomas (MLs) to chemotherapy using technetium-99m methsxyisobutylisonitri
le (Tc-MIBI) scan and to compare it with the predictive ability of P-glycop
rotein (P-gp) expression, multidrug resistance-related protein (MRP) expres
sion and other prognosis factors. Twenty-five ML patients were enrolled in
this study prior to initiation of chemotherapy. Images were obtained 10 min
after intravenous injection of Tc-MIBI, interpreted visually and the tumou
r-to-background (T/B) ratios calculated. Immunohistochemical analyses were
performed on sections of the biopsy specimens to determine P-gp and MRP exp
ression. Chemotherapy response was evaluated in the first 1-2 years after c
ompletion of chemotherapy. The mean T/B ratio of the 15 patients with a goo
d response (3.3 +/- 0.6) was significantly higher than that of the 10 patie
nts with a poor response (1.2 +/- 0.1). All 15 patients with a good chemoth
erapy response had positive Tc-MIBI scan results and negative P-gp and MRP
expression. All 10 patients with a poor response had negative Tc-MIBI scan
results and either positive P-gp or MRP expression. Other prognosis factors
showed no significant difference in the incidence of good and poor respons
es. Tc-MIBI scan results represent P-gp or MRP expression more accurately t
han other prognosis factors and predict the chemotherapy response in ML pat
ients.