Intracytoplasmic lysozyme in malignant hematologic disorders: an immunoperoxidase study

Area of Science:

• Hematopathology
• Immunohistochemistry
• Cancer Diagnostics

Background:

• Lysozyme is an enzyme found in myeloid and histiocytic cells.
• Distinguishing between different types of cancers, particularly myeloid/histiocytic versus lymphoid/epithelial, is crucial for effective treatment.
• Immunohistochemical methods offer sensitive detection of cellular markers.

Purpose of the Study:

• To investigate the utility of intracytoplasmic lysozyme as a diagnostic marker.
• To differentiate between various myeloproliferative, lymphoproliferative disorders, and metastatic tumors.
• To assess the reliability of lysozyme detection in different tissue preparations.

Main Methods:

• Utilized peroxidase antiperoxidase (PAP) and protein A-peroxidase techniques.
• Examined 130 cases of myeloproliferative and lymphoproliferative disorders.
• Analyzed 21 lymph node and bone marrow metastases from solid tumors, including formalin and Zenker-fixed tissues, peripheral blood, and bone marrow smears.

Main Results:

• Intracytoplasmic lysozyme was successfully identified in various sample types.
• The presence of lysozyme effectively distinguished malignant myeloid and histiocytic tumors.
• This marker differentiated these from malignant lymphoid and undifferentiated epithelial metastases.

Conclusions:

• Intracytoplasmic lysozyme is a valuable marker for distinguishing myeloid/histiocytic neoplasms from lymphoid and epithelial malignancies.
• The marker's detectability in diverse sample types enhances its diagnostic applicability.
• These findings support the use of lysozyme immunohistochemistry in routine pathology.