stage instit histol control case 
  1   1   1     226   91
  2   1   1     133  117
  3   1   1     124  100
  4   1   1      38   60
  1   1   2       6    9
  2   1   2       4   14
  3   1   2       5   15
  4   1   2       0    9
  1   2   1       2    1
  2   2   1       1    2
  3   2   1       4    3
  4   2   1       1    3
  1   2   2       6   16
  2   2   2       9   33
  3   2   2      10   57
  4   2   2       2   41