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Published on: April 13, 2015
Relation between natural killer cells and neoplastic cells in serous fluids
J A Laurini1, A Garcia, B Elsner
1Service of Pathology, Center for Medical Education and Clinical Investigation, Buenos Aires, Argentina.
Insights
Investigating natural killer cell percentage (NK%) in effusions revealed higher NK% in adenocarcinoma, aiding differential diagnosis. Lower NK% was observed in malignant mesothelioma and lymphoma, assisting in distinguishing these from adenocarcinoma.
Area of Science:
- Immunology
- Oncology
- Cytopathology
Background:
- Natural killer (NK) cells are crucial for tumor cell lysis in vitro.
- Assessing NK cell percentage (NK%) in serous effusions may correlate with malignancy presence.
Purpose of the Study:
- To determine the relationship between NK cell percentage in effusions and the presence of malignant cells.
- To evaluate the utility of NK% in differentiating between adenocarcinoma and other malignancies like malignant mesothelioma (MM) and malignant lymphoma (ML).
Main Methods:
- Analysis of 51 serous effusions (15 peritoneal, 36 pleural) from 47 patients.
- Lymphocyte immunophenotyping using flow cytometry to determine NK cell percentage (NK%).
- Comparison of NK% in effusions negative for malignancy versus those positive for adenocarcinoma, MM, ML, or rhabdomyosarcoma.
Main Results:
- Effusions positive for adenocarcinoma showed a significantly higher average NK% (22.08%) compared to malignancy-negative cases (5.09%) (P < 0.001).
- Malignant mesothelioma, malignant lymphoma, and rhabdomyosarcoma cases exhibited low average NK% (3.01%).
Conclusions:
- NK cell percentage in serous effusions can be a valuable biomarker.
- Elevated NK% suggests adenocarcinoma, while low NK% is indicative of other malignancies, aiding differential diagnosis in cytologically equivocal cases.
Abstract:
Natural killer (NK) cells are capable of lysing certain tumor cells in vitro. We investigated whether the percentage of NK cells (NK%) in serous effusions has any relation with the presence of malignant cells. Fresh effusions were routinely processed, and a portion of them was submitted for lymphocyte immunophenotyping, using a flow cytometer. Fifty-one fluids (15 peritoneal, 36 pleural), from 47 patients were analyzed. Thirty-two cases were negative and 19 were positive for neoplastic cells: there were 13 adenocarcinomas, 2 malignant mesotheliomas (MM), 3 malignant lymphomas (ML), and 1 rhabdomyosarcoma (R). Negative cases showed an average NK% of 5.09% (1-16%). Effusions positive for adenocarcinoma had an average NK% of 22.08% (12-33%) (P < 0.001). MM, ML, and R had a low NK%, with an average of 3.01% (0-5%). Investigation of the NK% could be useful in cytologically doubtful cases and in the differential diagnosis between MM and adenocarcinoma.
