Accuracy of FCM clustering

Sir, Can anyone please help me to write a code for finding the accuracy of FCM clustering algorithm which used for detecting lung cancer from CT scan images. I have tried with the following code but it is showing me constant values for accuracy,sensitivity and specificity for every data. Please help me to get through this.

clc;
clear all;
close all;

%load testmask5.mat % ground truth
%load twoglcm5.mat %segmented image

file = 'ok12grnd.jpg';  

initImage = imread(file);

%figure;
%imshow(mask); % ground truth
truth=imread(file);
% truth=im2bw(im);
figure;
f1='ok12out.jpg';
ou=imread(f1);
% ou=im2bw(im);
imshow(ou); %segmented image

adder = truth + ou;
%figure
%imshow(adder)
TP = length(find(adder == 2)); %true positive
TN = length(find(adder == 1)); %true negative
subtr = imsubtract(ou,truth);
figure
imshow(subtr)
FP = length(find(subtr >0)); %false negative
FN = length(find(subtr <0)); %false positive

p1= TP/(TP+FP); %precision
A5=(TP+TN)/(TP+TN+FP+FN); %accuracy
SN5=TP/(TP+FN); %sensitivity
SP5=TN/(TN+FP); %specificity

   %plot bar graph
  figure;
  y = [A5*100 SN5*100 SP5*100];
  bar(y,'b')
  Labels = {'Accuracy', 'Sensitivity', 'Specificity'};
  set(gca, 'XTick', 1:3, 'XTickLabel', Labels);
  ylim([0 100]);