Relation between natural killer cells and neoplastic cells in serous fluids

NK cells from pleural effusions are potent antitumor effector cells

“…The authors show that the percentage of NK cells in pleural effusions is comparable with that observed in the peripheral blood . This finding contrasts with results published by various groups, as the percentage of NK cells is enhanced in effusions mainly derived from adenocarcinomas , but effusions associated with mesothelioma, lymphoma or multiple myeloma contain a low percentage of NK cells . In the study by Vacca et al , NK cells were analyzed in the pleural effusions of patients with tumors of various origins including mesothelioma, lung, breast, colon, gastric, bladder and uterine carcinoma.…”

Flow cytometric quantitation of natural killer cells and T lymphocytes expressing T‐cell receptors alpha/beta and gamma/delta is not helpful in distinguishing benign from malignant body cavity effusions

“…The study by Guzman et al (7) involved only ovarian cancer‐related ascites. We analyzed a relatively robust number (30) of malignant effusions; others (3, 5) studied 15 or less. We paid particular attention to gating strategy to identify NK cells with precision.…”

“…In numerous reports, the degree of tumor infiltration by NK cells correlates directly with prognosis (1, 2). Comparison of percentage of NK cells in malignant versus benign cavity effusions has yielded conflicting results, with some studies showing a significant increase (3–5), others a significant decrease (6), and still others showing no difference (7, 8). One frequently quoted 1996 study from the Houston Veterans Affairs (VA) Hospital reported a highly statistically significant ( P < 0.00001) association between a high percentage of NK cells and metastatic malignancy in pleural and peritoneal effusions and asserted that (flow cytometric) measurement of NK cells in effusions was “a new, sensitive means of detecting carcinoma” (3).…”

Serous effusions: diagnosis of malignancy beyond cytomorphology. An analytic review

“…42 Flow cytometric determination of the percentage of natural killer lymphocytes can be useful to diagnose the metastatic effusion. Studies by Green and Griffin 44 and Laurini et al 45 have shown this as a quick procedure that appears to have a high sensitivity (100%) and specificity (96.8%) for the diagnosis of malignant effusions due to metastatic adenocarcinoma.…”