def variant_cv_tissue_site(value)
      # try an NOS suffix variation
      variation = value =~ /, NOS$/ ? value[0...-', NOS'.length] : value + ', NOS'
      SpecimenCharacteristics.tissue_site_controlled_value(variation) rescue nil
    end
def variant_cv_tissue_site(value)
      
      variation = value =~ /, NOS$/ ? value[0...-', NOS'.length] : value + ', NOS'
      SpecimenCharacteristics.tissue_site_controlled_value(variation) rescue nil
    end
def variant_cv_tissue_site ( value ) # try an NOS suffix variation variation = value =~ / / ? value [ 0 ... - ', NOS' . length ] : value + ', NOS' SpecimenCharacteristics . tissue_site_controlled_value ( variation ) rescue nil end
Returns the tissue site which adds the 'NOS' suffix to a value without one
 or removes 'NOS' from a value with the suffix.

 @return [String, nil] a supported variant of the input value, or nil if none
Returns the tissue site which adds the NOS suffix to a value without one or removes NOS from a value with the suffix .