stage instit histol control case 
  1   1   1     115   91
  2   1   1      86  117
  3   1   1      79  100
  4   1   1      27   60
  1   1   2       2    9
  2   1   2       3   14
  3   1   2       3   15
  4   1   2       1    9
  1   2   1      15    1
  2   2   1      11    2
  3   2   1      18    3
  4   2   1      23    3
  1   2   2      64   16
  2   2   2      51   33
  3   2   2      60   57
  4   2   2      13   41