Table 2

Categorization of immunostained cellsa

CategoryCharacteristicsDefinition
Positive caseATumor cellsTypical tumor cell morphology. Cell cluster, obviously enlarged or atypical nucleus. Never found in false positive.
Positive caseBProbable tumor cellsNo convincing hematopoietic cell characteristics. Classified as positive case only if no immunostained cells are present in the corresponding negative control specimen.
Negative caseCHematopoietic cells, squamous skin epithelial cellsImmunostained cells with hematopoietic cell-like morphology. Presence of immunostained cells on corresponding negative control specimen. Contaminating squamous skin epithelial cells.
Negative caseDNo cell detected
  • Criteria for evaluation of immunostained cells in bone marrow were adapted from Borgen et al. (27) based on the results of the European ISHAGE Working Group for standardization of tumor cell detection.