Intrapleural Corynebacterium parvum for recurrent malignant pleural effusions

Twenty-two consecutive patients with malignant pleural effusions (MPE) were treated with intrapleural Corynebacterium parvum (CBP) associated with parenteral methylprednisolone (MP) to determine its effectiveness and the frequency and nature of adverse reactions. After thoracentesis, 7 mg of CBP (Coparvax Wellcome) in 20 ml of saline were injected into the pleural cavity. On the day of treatment, the patients were given 1 mg/kg i.m. of MP 30 min before thoracentesis. The effectiveness of pleurodesis was assessed as follows: (1) complete response (CR; total resolution of pleural effusion after 3 injections of CBP at the most); (2) partial response (PR; formation of asymptomatic loculated effusion). In 5 patients leukocytes, lymphocytes and monocytes were determined in pleural fluid (PF) and in blood (B) collected before and 7 days after CBP treatment. Two patients were unevaluable. Of 20 evaluable patients, 18 (90%) had a CR and 2 patients (10%) had a PR. Eleven of 22 patients (50%) had a fever. Three patients had prolonged and/or high fever. Seven of 22 patients (32%) had mild chest pain. None of the patients presented other side effects. Twelve of 21 patients (57.1%) had a PF pH > or = 7.30; 2 of these died a few days after the treatment, and 10 had favorable responses. The other 9 patients had a PF pH < 7.30: all had favorable responses. The leukocytes, the lymphocyte subsets, the monocytes, the NK lymphocytes, and their PF/B ratios did not differ significantly before and after CBP treatment. Our study confirms that intrapleural CBP is an effective and simple method to control MPE.(ABSTRACT TRUNCATED AT 250 WORDS)

[Diagnostic value of tissue polypeptide antigen in pleural effusions with malignant pleural mesothelioma]

There are no known tumor makers of malignant pleural mesothelioma. We measured the concentration of TPA in the pleural effusions from patients with malignant pleural mesothelioma and from patients with other pleural diseases, evaluate its clinical usefulness. The concentration of TPA was more than 7,000 U/l (mean: 18,600 +/- 9,867 U/l, n = 5) in all patients with malignant pleural mesothelioma, but it was less than 4,000 U/l in those with benign asbestos pleurisy and other benign pleural effusion (benign asbestos pleurisy 1,598 +/- 570, n = 5: p < 0.01, tuberculous pleurisy 1.37 +/- 759, n = 11: p < 0.01, others 2,497 +/- 2,152 n = 3: p < 0.05). The concentration of TPA in the pleural effusions was not significantly different between malignant pleural mesothelioma and lung cancer (12,287 +/- 17,070 U/l). However, in all patients with lung cancer and high TPA concentrations, cytologically malignant cells were detected in the pleural effusions. TPA was high in all five patients with malignant pleural mesothelioma, but cytologically malignant cells were detected in only one patient. Only in malignant pleural mesothelioma (not in other benign disease or in lung cancer) was the concentration of TPA more than 4,000 U/l, and no evidence of malignancy was obtained by cytological methods. These findings suggest that assessing TPA in the pleural effusion might contribute to the diagnosis of malignant pleural mesothelioma.

Transforming growth factor-beta 1 (TGF-beta 1)- and beta 2-like activities in malignant pleural effusions caused by malignant mesothelioma or primary lung cancer

We investigated the levels of TGF-beta in malignant pleural effusions (MPE) caused by malignant mesothelioma (MESO) or primary lung cancer. TGF-beta levels in MPE caused by MESO were 283.9 +/- 219.2 pm (mean +/- s.d.) and were three to six times higher than those due to primary lung cancers (P < 0.01 or P < 0.05). We also evaluated TGF-beta 1- and beta 2-like activities in MPE using specific polyclonal antibodies. Although TGF-beta 1-like activity could be detected in all cases, TGF-beta 2-like activities were detected in five of seven in MESO and in a few cases with primary lung cancer. These results demonstrate that the levels of total TGF-beta and TGF-beta 2-like activity may be clinically useful to differentiate MESO from primary lung cancer. Our data also suggest that TGF-beta may help further characterize the clinical features of MESO.

Mononuclear cells in exudative malignant pleural effusions. Characterization of pleural phagocytic cells

The aims of this study were to develop a methodology for the isolation of highly enriched mononuclear phagocyte populations from exudative malignant pleural effusions (EMPE) and to characterize the phenotype and functional properties of these cells. Pleural effusion mononuclear cells (PEMC) were isolated by Ficoll centrifugation of EMPE and transudative pleural effusions and allowed to adhere to plastic for 1 h to obtain a pleural effusion mononuclear adherent cell (PEMAC) fraction. Only 66.0 +/- 4.2 percent of PEMAC ingested latex particles, indicating that a significant proportion of PEMAC were not phagocytic cells. Latex-positive PEMAC had the morphologic appearance of macrophages and stained positive (97.3 +/- 4.3 percent) with the anti-CD68 monoclonal antibody (MoAb), specific for macrophages. Conversely, latex-negative PEMAC (34.0 +/- 4.1 percent of PEMAC) did not react with the anti-CD68 MoAb and stained with anti-CD3 (34.7 +/- 10.7 percent) and anticytokeratin (50.5 +/- 16.4 percent) MoAbs, indicating that T cells and mesothelial cells were present in the PEMAC fraction. To improve the purification of pleural macrophages, PEMAC were cultured for an additional 18 h and the cells that remained adherent after this period constituted the firmly adherent mononuclear cell (FAMC) fraction. Nearly 90 percent of FAMC ingested latex particles and were CD68-positive. Virtually all FAMC were CD3-negative and cytokeratin-negative. Similar percentages of FAMC from EMPE and transudative effusions expressed the monocyte-lineage markers CD11b and CD14, suggesting that the proportion of monocyte-like mononuclear phagocytes in the pleural space is not increased during local tumor-associated inflammatory responses. The FAMC from EMPE (1) expressed HLA-DR antigens, (2) released interleukin 1 (IL-1) beta and tumor necrosis factor (TNF) alpha, and (3) stimulated allogeneic T-lymphocyte proliferation. The results of this study suggest that pleural mononuclear phagocytes may be involved in tumor-associated inflammatory reactions in the pleural compartment by stimulating the proliferation of other inflammatory cells and by releasing inflammatory cytokines.

Immunocytochemical differentiation of reactive mesothelial cells and adenocarcinoma cells in serous effusions with the use of carcinoembryonic antigen and fibronectin

Ninety effusions from patients with breast and ovarian cancer were studied cytologically and classified as benign, suspicious or malignant, and the same samples were studied for carcinoembryonic antigen (CEA) and fibronectin (F) immunostaining. The combination F positive/CEA negative was found to have 100% specificity and 92.3% sensitivity in patients with benign or reactive effusions, and F negative/CEA positive 85.7% specificity and 80.7% sensitivity for malignancy. Immunostaining provides valuable supplementary information in cytologically suspicious patients. In the presence of F negative/CEA negative effusions, it is probable that insufficient cellular material is present for either a cytologic or immunostaining diagnosis.

Tumor specific cytolysis by tumor infiltrating lymphocytes in breast cancer

BACKGROUND

In vitro studies have demonstrated that exposure of tumor infiltrating lymphocytes (TIL) to human recombinant interleukin-2 (rIL-2) will generate activated T-lymphocytes with major histocompatibility complex (MHC)-restricted and non-MHC-restricted cytotoxicity toward a panel of tumor target cells. In melanoma and ovarian carcinoma, TIL display MHC-restricted and autologous tumor-specific cytotoxicity. Such tumor-reactive cytotoxic T-lymphocytes (CTL) represent important material for understanding cellular immunity in cancer and developing specific immunotherapeutic approaches in melanoma and ovarian cancer. In breast cancer, some TIL have been demonstrated to secrete cytokines upon interaction with autologous tumor cells, indicating that autologous tumor-reactive lymphocytes may also exist among TIL in breast cancer. Therefore, the authors conducted a study to investigate the cytotoxic profile of rIL-2-activated lymphocytes in breast cancer.

METHODS

Lymphocytes were isolated from primary solid tumors (TIL) of breast carcinomas (10 patients) and from peritoneal effusions (effusion-associated mononuclear cells [EAMNC]) from 2 patients with newly diagnosed metastatic breast carcinoma. Tumor infiltrating lymphocytes or EAMNC were cultured with rIL-2 in long term cultures whereby their expansion index, phenotype, and cytotoxic potential were studied.

RESULTS

Both TIL and EAMNC proliferated by greater than 300-fold (370-3650; mean, 1656) after 23-82 days in cultures containing mixtures of TIL or EAMNC, autologous tumor cells, and rIL-2. By fluorescence analysis, freshly isolated TIL and EAMNC were found to consist of 77.5 plus or minus 10.7% CD3+ T-cells, 33.2 plus or minus 8.9% CD4+, and 47.2 plus or minus 16.8% CD8+ cells. Their CD4 to CD8 ratio was 0.70. After expansion of lymphocytes with rIL-2 in the majority of patients (9 of 12), CD3+CD8+ T-lymphocytes were present in greater numbers than CD3+CD4+ T-lymphocytes. Recombinant interleukin-2-activated CD3+CD8+ cells exhibited preferential cytolytic activity against autologous tumor cells. The cytolytic activity of CD3+CD8+ cells was inhibited either by anti-T-cell receptor (TCR)-alpha/-beta and anti-CD3 monoclonal antibodies (MoAb) or after pretreatment of tumor target cells with MoAb against the class I MHC antigens. Recombinant interleukin-2-activated CD3+CD4+ cells demonstrated potent cytolytic activity against both autologous and allogeneic tumor cells. CD3+CD8+ T-cell clones isolated from representative TIL exhibited preferential autologous tumor-specific cytotoxicity whereas the cytolytic activity of CD3+CD4+ T-cell clones was mostly (12 of 14 clones) nonrestricted to the autologous tumor.

CONCLUSIONS

To the authors' knowledge, this is the first report to demonstrate that TIL from primary tumors of breast carcinomas and EAMNC from metastatic disease can be propagated in large numbers in vitro with rIL-2 while retaining autologous tumor specific and MHC-restricted CTL activity. These findings may be of importance to ongoing clinical trials using TIL or EAMNC in the immunotherapy of patients with advanced breast cancer.

Pleural effusion in multiple myeloma

We report the first case of IgA-kappa multiple myeloma presenting as a myelomatous and eosinophilic pleural effusion with increased adenosine deaminase activity. In a review of the literature, 80 percent of myelomatous pleural effusions are due to IgA multiple myeloma.

Recruitment of inflammatory cells to the pleural space. Chemotactic cytokines, IL-8, and monocyte chemotactic peptide-1 in human pleural fluids

Pleural effusions secondary to various diseases are associated with the presence of different inflammatory cells. The role of selective chemotactic cytokines in the recruitment of phagocytes to the pleural space is unclear. IL-8 and monocyte chemotactic peptide-1 (MCP-1) are recently described cytokines that are chemotactic for neutrophils and monocytes, respectively. We prospectively studied 63 patients, using strictly defined criteria for their selection. IL-8 concentrations were elevated in both empyema fluid (9.15 +/- 0.89 ng/ml) and parapneumonic effusions (4.7 +/- 0.697 ng/ml) when compared with pleural effusions secondary to other diseases. IL-8 levels were higher in empyema fluid than in parapneumonic effusions (p = 0.01). There was a significant correlation between IL-8 levels and the total numbers of neutrophils in empyema fluids (r = 0.80). Chemotactic activity for neutrophils was elevated in empyema fluid and the addition of IL-8 neutralizing serum decreased bioactivity by 32.22%. Malignant pleural effusions had the highest levels of MCP-1 (12.0 +/- 3.7 ng/ml) when compared with others. Cytology-positive pleural fluids (n = 10) had a higher level of MCP-1 than cytology-negative effusions (p = < 0.05). Malignant pleural fluid MCP-1 levels correlated (r = 0.70) with the absolute number of monocytes in the pleural fluid. Neutralization of monocyte chemotactic activity of malignant pleural fluid by specific neutralizing serum caused a 70.3% inhibition of bioactivity. Immunohistochemical staining of malignant pleural fluid localized antigenic MCP-1 to malignant cells. We conclude that both IL-8 and MCP-1 play major but not exclusive roles in the recruitment of neutrophils and monocytes from the vascular compartment to the pleural space.

The intrapleural administration of recombinant interleukin-2 (rIL-2) to patients with malignant pleural effusion: clinical trials

Recombinant IL-2 (rIL-2) was administered intrapleurally according to an original protocol to 11 patients with malignant pleural effusion, 7 of whom suffered from breast cancer and 4 from esophageal cancer. The pleural effusions either disappeared or decreased roentgenographically, and malignant cells disappeared from all 13 pleural cavities in the 11 patients, confirming the validity of this therapy to be 100%. The mean survival time from the initial administration of rIL-2 was 15.9 months. We ensured that the concentration of IL-2 in the effusion was maintained at a high level for a sufficient period of time, and that the lymphokine-activated killer (LAK) activity of lymphocytes in the effusion was augmented. Fever, eosinophilia, and a transient increase in the pleural effusion were the main side effects, but the symptoms were temporary and not serious. The results of this study therefore suggest the efficacy of intrapleural rIL-2 for patients with malignant pleural effusion.

Induction of cytolytic activity of lymphocytes from carcinomatous pleural effusion by IL-2 and autologous tumor cells

We established a cell line (STKM-1) from tumor cells obtained from carcinomatous pleural effusion of a gastric cancer patient. The lymphocytes separated from her peripheral blood or pleural effusion were cryopreserved and immunological experiments were performed after the establishment of the cell line. They were treated with IL-2 or with both IL-2 and mitomycin C (MMC)-treated autologous STKM-1 cells. The cytolytic activity against STKM-1 cells was elevated in lymphocytes cultured with IL-2, and was more prominently augmented in lymphocytes cultured with both IL-2 and MMC-treated STKM-1 cells. The elevation in cytolytic activity was more marked with pleural effusion lymphocytes than with the peripheral blood lymphocytes. The results suggest that the lymphocytes obtained from the pleural effusion would be an excellent source for adoptive immunotherapy.

Induction of inflammatory cytokines in the pleural effusion of cancer patients after the administration of an immunomodulator, OK-432: role of IL-8 for neutrophil infiltration

When OK-432, a well-known streptococcal preparation for an anti-tumour drug, was administered into the pleural cavity of patients with malignant pleurisy, a rapid and prominent leukocytosis, predominantly consisting of neutrophils, was observed in the cavity. Neutrophil infiltration usually peaked 6-9 h after OK-432 administration, and levelled down after 24 h. Prior to the neutrophil accumulation, transient but marked elevation of various inflammatory cytokine levels including IL-1 beta, TNF-alpha, IL-8 and G-CSF was observed. In particular, IL-8 levels increased more than 10-fold, while GM-CSF did not change significantly. A good correlation between IL-8 levels and neutrophil chemotactic response was observed particularly during 0-3 h. Specific neutralization or removal of IL-8 by antibody column abrogated half of the neutrophil chemotaxis, while neutralization of C5a removed around 40%. Sequential removal of IL-8 and C5a abrogated totally 80% of chemotaxis, confirming that these two factors are mostly responsible for the neutrophil chemotaxis in the pleural fluids. These results have suggested that rapid neutrophil infiltration induced by OK-432 in vivo is ascribable largely to IL-8 and in part to C5a.

Phenotypes and lymphokine-activated killer activity of pleural cavity lymphocytes of lung cancer patients without malignant effusion

We examined the phenotypes of lymphocytes in the pleural cavity of 23 lung cancer patients without malignant effusion. The ability of those lymphocytes to develop lymphokine-activated killer (LAK) activity and the regulation of LAK by pleural cavity macrophages were also compared with their counterparts in the peripheral blood. Mononuclear cells (MNC) were obtained simultaneously from the blood and by lavage of the pleural cavity of patients with lung cancer. The proportion of the T-cell subset of HLA-DR+ cells was significantly higher in the pleural cavity than in the peripheral blood, but the proportions of CD3+ and CD8+ cells in the pleural cavity were similar to the corresponding proportions in the blood. The proportions of CD4+ and CD16+ cells were lower in the pleural cavity than in the blood. The LAK activity could be developed by MNC from the pleural cavity following incubation with interleukin 2 (IL-2), but the LAK activity of pleural cavity MNC was significantly less than that of peripheral MNC. Pleural cavity lymphocytes alone also developed LAK activity following incubation with IL-2. Pleural macrophages from the patients were regulated to augment in vitro induction of LAK activity by IL-2 from autologous blood lymphocytes and pleural cavity lymphocytes. Lymphocytes in the pleural cavity without malignant pleural effusion could be developed by LAK activity and this activity was augmented by pleural cavity macrophages. The LAK activity developed by pleural cavity lymphocytes was significantly lower than that developed by peripheral blood lymphocytes. However, they can change their population to include cells with higher activities on exposure to IL-2 against the invasion of lung cancer cells into the pleural cavity. Thus, the population of lymphocytes in the pleural cavity of patients with lung cancer without malignant pleural effusion was different from that in malignant pleural effusion.

Effect of storage time on the analysis of lymphocyte subpopulations in pleural effusions

It is not known how long cell surface antigens can be detected on lymphocytes in pleural effusions. Therefore, the lymphocyte subpopulations of 15 native pleural effusions were analyzed after different storage times, at either 4 degrees C or room temperature, using the peroxidase-antiperoxidase adhesive slide assay. No significant differences in the lymphocyte subpopulations were observed after one day of storage under both conditions, although the immunoreactivity with CD4 was poor in the majority of cases stored at 4 degrees C and in two cases stored at room temperature. After three days of storage at 4 degrees C and after four days of storage at room temperature, a marked decrease in lymphocytes attached to the slides was observed. Immunoreactivity with CD8, CD20, CD45 and HLA-1 was well preserved, also, after one week of storage. Reactivity with CD3 was weak or poor after three days of storage in some cases. It is important to recognize that the preservation of the immunoreactivity of lymphocytes is dependent not only on the nutritive quality of pleural fluids but also on the cell preparation method.

Interferon instillation for malignant pleural effusions

BACKGROUND

Malignant pleural effusions can be managed in various ways including instillation of antineoplastic agents. Instillations of alfa interferon-2b (IFN-alpha 2b) have been utilized with success in various loco-regional malignancies suggesting a possible role in management of pleural effusions. This trial was designed to evaluate the tolerability and efficacy of intrapleural IFN-alpha 2b instillations in this situation.

PATIENTS AND METHODS

Twenty-three patients with cytologically proven malignant pleural effusions were given IFN-alpha 2b 50 x 10(6) units in 50 ml normal saline (NS) by intrapleural instillation after partial or complete clearance of effusions by percutaneous aspiration or chest tube drainage. For persistent or recurrent effusions, instillations were repeated with dose escalation to 75 x 10(6) units. Patients were assessed and monitored by regular clinical examinations, chest radiographs, biochemical and hematological parameters and assays of lymphocyte subpopulations until relapse or death in each case.

RESULTS

Fourteen of 20 evaluable patients (70%) had responses lasting for a median of 6 months; there were 8 complete responses (CR) and 6 partial responses (PR). In 6 CR patients the effusions did not recur after the first instillation. In 2 of 6 other patients, the second instillation was successful in inducing CR. Intrapleural instillation of IFN-alpha 2b was well tolerated, no grade 4 toxicities were encountered. There were no significant effects on any of the studied parameters at the initial dose level; however, grade 3 neutropenia occurred with the escalated dose. The most common toxicity was flu-like syndrome, after 70% of the instillations.

CONCLUSIONS

Intrapleural instillation of IFN-alpha 2b produced an encouraging response rate without significant toxicities. This approach may warrant additional phase II or phase III comparative clinical studies.

The characterization of peritoneal and pleural exudate cells from malignant effusions

The immune function of peripheral blood cells and cells from the pleural and abdominal effusions of patients with advanced cancer was compared to that of peripheral blood cells from controls. The parameters examined included lymphocyte subsets, natural killer (NK) cell activity, and anti-Daudi and lymphokine-activated killer (LAK) cell activity. The percentage of CD4+ pleural and peritoneal exudate cells (PEC) was significantly higher than the percentage of peripheral blood mononuclear cells (PBMC) in the patients. The percentage of CD8+CD11+ PEC and PBMC, being the suppressor T-cells, of the patients was increased compared with controls, while the percentage of CD8+CD11- PEC, being the cytotoxic T-cells, was identical to the PBMC of both patients and controls. The NK activity of PEC was significantly lower than that of PBMC in both patients and controls, and there was no correlation between the NK activity of PBMC and PEC. Although the anti-Daudi activity of PEC was markedly low, LAK cells with high activity could be induced by culture with interleukin-2 for 4 days. These results suggest that the immune function of cells in malignant effusions may be depressed due to a low population of cytotoxic T cells, low NK activity and increased suppressor T cells, while the local administration of interleukin-2 may induce LAK cells. Therefore, effective local immunotherapy for malignant effusions should not only augment effector cells, but also inhibit suppressor cells.

Gamma-interferon enhances the cytotoxic activity of interleukin-2-induced peripheral blood lymphocyte (LAK) cells, tumor infiltrating lymphocytes (TIL), and effusion associated lymphocytes

The effect of gamma-interferon (IFN-gamma) on the induction of interleukin-2 (IL-2) activated killer cell activity was studied: (I) in peripheral blood lymphocytes (LAK cells) from cancer patients and healthy donors, (II) in lymphocytes infiltrating solid tumors (TIL) from melanoma and breast cancer patients, and (III) in pleural effusion associated lymphocytes (EAL) from patients with lung adenocarcinoma. The coculture of LAK, TIL and pleural effusion mononuclear cells (MNC) with several doses of IFN-gamma (10, 50, 250, and 1250 U/ml) and a low dose of IL-2 (10 U/ml) for 5 days resulted in a synergistic effect on the cytotoxicity of these cells against several tumor cell lines. Furthermore there was a potentiation in the proliferation of MNC after a 5-day culture. The induction of lymphocyte cytotoxicity by a combination of IFN-gamma with low doses of IL-2 may be helpful in designing more effective cancer immunotherapeutic protocols with LAK, TIL or EAL.

Antigenic modulation of metastatic breast and ovary carcinoma cells by intracavitary injection of IFN-alpha

Antigenic modulation of major histocompatibility and tumour associated antigens was observed in neoplastic cells obtained from patients with pleural and abdominal effusions of breast and ovary carcinomas following a single intracavitary dose of 18 x 10(6) U recombinant IFN-alpha. This regimen resulted in antigenic modulation in seven out of 11 tested cases, suggesting a potential, although limited, responsiveness of at least a fraction of breast and ovary carcinoma cells to in situ biomodification with IFN-alpha.

IL-6 in malignant pleural effusions and its augmentation by intrapleural instillation of IL-2

The levels and activities of endogenous IL-6 in malignant pleural effusions due to lung cancer before and during daily intrapleural instillations of recombinant IL-2 were examined by enzyme immunoassay and bioassay using an IL-6-dependent murine hybridoma cell line MH60.BSF2. Before therapy, malignant pleural effusions contained various levels of IL-6. Daily intrapleural instillation of recombinant IL-2 for treatment of malignant pleurisy resulted in significant augmentation of the levels and activities of IL-6 in the pleural effusions. On fractionation of the pleural effusion by chromatography, one major peak of material with a mol. wt of 24 kD showed IL-6 activity. In contrast, no significant level of tumour necrosis factor-alpha or IL-1 beta was detectable in pleural effusions before or during local IL-2 therapy. These data suggest that IL-2 is an important regulatory factor of secondary IL-6 production.

Detection of a soluble antigen defined by monoclonal antibody 83D4 in serous effusions associated with breast carcinoma

Monoclonal antibody (MoAb) 83D4 was generated by immunization with cell suspensions obtained from sections of formol-fixed paraffin embedded human breast cancer. It recognized an antigen expressed in breast carcinomas but not in normal breast tissue. Pleural and ascitic fluids from 66 patients were studied by an 83D4 heterologous sandwich radioimmunoassay (SRIA) using solid-phase immobilized wheat germ agglutinin to detect the 83D4 soluble antigen. Using a cutoff level of 5 units/ml of 83D4 antigen, higher values were found in 22 of 27 breast cancer-associated effusions (mean = 10.72 +/- 6.80 units/ml). The 20 nonmalignant effusion fluids tested showed lower values (mean = 1.16 +/- 1.49 units/ml, P less than 0.001). The antigen was undetectable or present in low levels in effusions from patients with hematologic malignancies. When SRIA results were compared with conventional cytologic diagnosis in breast-cancer effusions, elevated levels of 83D4 soluble antigen were found in all patients (8 of 8) in whom malignant cells had been detected, in 4 of 8 patients with the diagnosis of "suspected malignancy," and in 10 of 11 patients with negative cytologic findings. Using an immunoglucosidase method on cell smears of various origins, MoAb 83D4 stained metastatic cells of breast and ovary carcinomas but did not reactive with mesothelial cells and other normal or malignant cell types. These results suggest that quantitation of the 83D4 soluble antigen may be used to improve the diagnosis of cancer in serous effusions.

Selected monoclonal antibodies can increase the accuracy of cytodiagnosis of neoplastic effusions of cryptic origin expanded in a short term culture

The use of a selected panel of monoclonal antibodies (MoAb) to tumor associated antigens (TAA) in immunocytochemical (IIC) tests has been shown, in a preliminary study, to be a powerful diagnostic tool for the identification of the primary solid tumor causing metastatic effusion. Despite this improvement in a minority of neoplastic fluids a number of different causes may still determine false negative (FN) immunocytochemical diagnoses. The aim of the present study was to confirm the diagnostic accuracy of this panel of MoAb. This was done by analyzing in IIC tests a larger number of effusions and by evaluating whether the expansion in short term culture of those fluids with an uncertain malignant morphology could provide an adequate cellular substrate for immunocytodiagnosis. The analysis of 314 effusions confirmed the results of the pilot study and demonstrated that the combination of short term culture and immunocytochemical assays can further increase the sensitivity of this novel diagnostic procedure from 84.3% to 95.3%.

[Carcinoembryonic antigen in pleural effusion. Adenocarcinoma versus mesothelioma]

One hundred and thirty six patients presenting pleural effusion and whose diagnosis was obtained by clinical, biochemical, bacteriological, cytological and histological methods have been studied and classified into seven groups: 20 transudates, 29 inflammatory, 25 tuberculosis, 25 non adenocarcinoid neoplasias, 24 adenocarcinomas, 10 mesotheliomas and 3 miscellaneous. Carcinoembryonic antigen was determined in all of them, evaluating as positives those values above 10 ng/ml, value which we consider discriminatory in our series and which agrees with the literature, finding positive values in 21 out of 24 adenocarcinomas and 3 out of 25 non adenocarcinomas. All benign pleural effusions and mesotheliomas had values lower than 10 ng/ml. The specificity to determine adenocarcinomas in neoplastic effusions was 91.48% and the sensibility was 87.5%. We consider that the CEA determination is useful to differentiate adenocarcinomas from other neoplasias and that a positive value rules out mesothelioma.

Identification of carcinoma cells in ascitic and pleural fluid. Comparison of four panepithelial antigens with carcinoembryonic antigen

The cell membrane antigens epithelial membrane antigen (EMA), epithelial glycoprotein 34, (egp34), BW-495 and tumor-associated antigen 72 (TAG-72) are present in most benign and malignant epithelial cells and can be demonstrated with the help of monoclonal antibodies. In a study on the identification of carcinoma cells in samples of ascitic and pleural fluid involving 170 patients, we compared the value of immunocytochemical labeling of these antigens with that of immunocytochemical demonstration of carcinoembryonic antigen (CEA). Antibodies to EMA and egp34 occasionally also reacted with reactively proliferating mesothelial cells in benign conditions and thus appear to be inappropriate for diagnostic use. Cells positive for BW-495, TAG-72 and CEA, however, have never been found in benign conditions; the specificity of these antigens thus permits their use in diagnosis. Antigen-expressing cells were found in 85% (BW-495), 62% (TAG-72) and 60% (CEA) of cytologically positive samples from carcinoma patients. Similarly, positive reactions for BW-495, TAG-72 and CEA were observed in, respectively, 36%, 29% and 34% of cytologically negative or suspicious samples. BW-495 thus appears to be a suitable marker for the demonstration of carcinoma cells in samples of pleural and ascitic fluid and to have a higher degree of sensitivity than does either TAG-72 or CEA.

Neopterin in tuberculous and neoplastic pleural fluids

Neopterin is derived from guanosine-triphosphate, produced by stimulated macrophages under the influence of gamma interferon of lymphocyte origin. It has been suggested as an excellent marker for activation of the monocyte/macrophage axis in some clinical situations. We evaluated its concentration in the pleural effusions of 25 individuals (10 tuberculous and 15 neoplastic) as well as in the blood of 22 of them (8 tuberculous and 14 neoplastic), comparing these levels with those of a control group in 99 normal individuals. The concentration of neopterin was determined by radioimmunologic assay. This showed a significant increase (p less than 0.001) of neopterin levels in the tuberculous pleural fluid, compared to the neoplastic group (42 +/- 23/17 +/- 9 nmol/L). In the blood, values were nearly identical to the pleural fluid (41.3 +/- 25/15.8 +/- 6.9 nmol/L), although with significant differences between them and in relation to the control group (p less than 0.001), which had a normal serum value (5.11 +/- 1.92 nmol/L). We emphasize the influence of the neopterin levels in the pleural fluid on the diagnosis of causes of pleurisy and its importance as a marker of immunologic cellular activity.

Identification of colony-stimulating factor activity in patients with malignant tumors associated with excessive leukocytosis

We have tried to demonstrate and identify colony-stimulating factor (CSF) activity in the plasma, pleural fluid, ascites or culture supernatant of tumor cells in 11 patients with malignant tumors associated with unexplained persistent leukocytosis. The specimens were treated with anti-granulocyte (G)-CSF or anti-granulocyte/macrophage (GM)-CSF monoclonal antibodies, then added to GM-progenitor (CFU-GM) cultures without exogenous CSFs. In all patients, untreated specimens generated CFU-GM-derived colonies, and colony formation was clearly inhibited by only one of the two antibodies, indicating the presence of either G-CSF or GM-CSF in the specimens. Furthermore, we measured the concentrations of G-CSF or GM-CSF in the specimens using an enzyme-linked immunosorbent assay, and confirmed the results by CFU-GM assay. Two patients were shown to have GM-CSF-producing tumors, while the other patients were G-CSF-producing. These assays are useful in identifying CSF activity in patients with CSF-producing tumors.