Individual development and uPA-receptor expression of disseminated tumour cells in bone marrow: a reference to early systemic disease in solid cancer.

It is unclear whether disseminated tumour cells detected in bone marrow in early stages of solid cancers indicate a subclinical systemic disease component determining the patient's fate or simply represent mainly irrelevant shed cells. Moreover, characteristics differentiating high and low metastatic potential of disseminated tumour cells are not defined. We performed repeated serial bone marrow biopsies during follow-up in operated gastric cancer patients. Most patients with later tumour relapse revealed either an increase or a constantly high number of tumour cells. In contrast, in patients without recurrence, either clearance of tumour cells or negative or low cell counts were seen. Urokinase plasminogen activator (uPA)-receptor expression on disseminated tumour cells was significantly correlated with increasing tumour cell counts and clinical prognosis. These results demonstrate a systemic component in early solid cancer, indicated by early systemically disseminated tumour cells, which may predict individual disease development.

The cellular receptor (CD4) of the human immunodeficiency virus is expressed on neurons and glial cells in human brain.

The expression of the CD4 antigen in normal human brain was investigated in parallel by immunohistochemical and Northern blot analyses. With anti-CD4 antibodies detecting different epitopes of the molecule, CD4+ neurons were defined in the cerebellum, thalamus, and pons. CD4+ glial cells were identified in the thalamus and pons. CD4-specific mRNA was detected in all three subareas and in the hippocampus, while other subareas were negative. The CD4+ cells were negative with anti-T cell antibodies (anti-CD2 and anti-CD8), as well as with antimonocyte antibodies (M-M 522 and M-M 42).

Differential expression of proliferation-associated molecules in individual micrometastatic carcinoma cells.

BACKGROUND: The development of monoclonal antibodies (MAbs) to cytokeratins, which are integral components of the epithelial cytoskeleton, has made possible immunocytochemical detection of epithelial tumor cells. Importantly, this technique allows the detection of epithelial tumor cells that have metastasized from primary adenocarcinomas to secondary sites such as the bone marrow. PURPOSE: The aim of the study was not only to detect micrometastatic cells in bone marrow, but also to assess the expression of nuclear proliferation markers (Ki-67 and p120) and the erbB2 oncogene (also known as ERBB2) in these cells and, thus, hopefully improve prognostic precision. METHODS: Bone marrow aspirates were obtained from both sides of the upper iliac crest of 532 patients having definitive diagnoses of either breast or gastrointestinal cancer. The presence of micrometastatic epithelial tumor cells in bone marrow was assayed using the MAb cytokeratin 2 (CK2) to cytokeratin component 18 (CK18), in combination with the alkaline phosphatase-anti-alkaline phosphatase immunostaining technique. After primary screening of all marrow samples with MAb CK2, representative subgroups of CK18+ samples were selected for co-labeling with MAbs either to ErbB (n = 16), ErbB2 (n = 121), Ki-67 (n = 33), or p120 (n = 36) protein. An alternative labeling protocol based on the combination of immunogold and immunoenzymatic techniques was utilized to confirm the results derived from immunoenzymatic double staining. RESULTS: In total, single CK18-positive tumor cells were detected in 180 (33.8%) of 532 bone marrow aspirates, with few differences among patients with breast or gastrointestinal cancer in TNM stage M0 (i.e., no distant metastasis). In patients with overt metastasis (stage M1), however, the incidence of metastatic cells in marrow increased to 73.7% in breast cancer, 52.5% in gastric cancer, and 39.0% in colon cancer. Whereas expression of Ki-67 or p120 on micrometastatic cells was observed only in 11 (15.9%) of 69 cancer patients analyzed, ErbB2+/CK18+ cells were found in 48 (67.6%) of 71 breast cancer patients and 14 (28.0%) of 50 patients with gastrointestinal cancer (P = .0001). The incidence of ErbB2+/CK18+ cells was positively correlated with the clinical stage of tumor progression. CONCLUSIONS: The high incidence of ErbB2 expression on micrometastatic breast cancer cells in the bone marrow suggests that these cells might have been positively selected during early stages of metastasis. The majority of these cells appear to be in a dormant state of cell growth. IMPLICATIONS: Although support from clinical follow-up is still needed, this study demonstrates that, beyond the mere presence of micrometastatic cells in bone marrow, useful prognostic information can be obtained by analysis of additional cell growth markers.

Frequent down-regulation of major histocompatibility class I antigen expression on individual micrometastatic carcinoma cells.

An astoundingly high frequency of micrometastatic cells have been found in bone marrow aspirates of patients with colon carcinomas (G. Schlimok et al., J. Clin. Oncol., 8:831-837, 1990), although these tumors very rarely metastasize to the skeleton. This observation has raised questions about the malignant potential of such cells. In a first attempt to characterize this potential, we have assessed the expression of major histocompatibility complex (MHC) class I antigens on bone marrow micrometastases, inasmuch as down-regulation of these molecules is a potential mechanism to escape from MHC class I-restricted lysis by cytotoxic T-cells. The two groups of cancer patients compared were those with tumors known to rarely (stomach and colon cancer) or frequently (breast cancer) manifest skeleton metastases. Bone marrow aspirates taken from these patients were probed for individual disseminated tumor cells using the immunoalkaline phosphatase technique with monoclonal antibody CK2 to the epithelial differentiation antigen cytokeratin 18 (CK-18), as described previously (G. Schlimok et al., Proc. Natl. Acad. Sci. USA, 84:8672-8676, 1987). Specimens containing CK18-positive cells were colabeled with monoclonal antibody W6/32 directed to a framework (or nonpolymorphic) antigenic determinant of MHC class I heavy chains associated with beta 2-microglobulin. W6/32-positive CK-18-positive cells could be detected in 25 of 54 patients (46.3%) with significantly higher incidences in 26 breast cancer patients (61.9%) as compared to 28 patients with carcinomas of the stomach and colon (27.3 and 29.4%). Independent from the origin of the primary carcinoma, the incidence of W6/32-negative CK18-positive cells was positively correlated to both the differentiation grade of the primary tumor (P less than 0.05) and appeared to be linked to the occurrence of regional lymph node metastases (statistically not significant) determined by conventional histological examination. The present results demonstrate for the first time that down-regulation of MHC expression on individual micrometastatic cells correlates to the differential pattern of metastasis obtained by comparing breast and gastrointestinal carcinomas. This finding together with the suggestive link to clinical risk factors supports the significance of reduced MHC class I expression for the survival of residual metastatic cells which is a major determinant of prognosis for patients with solid tumors.

E-cadherin expression in primary and metastatic gastric cancer: down-regulation correlates with cellular dedifferentiation and glandular disintegration.

Expression of the epithelial cell adhesion molecule E-cadherin in primary and metastatic gastric carcinoma was examined using immunohistochemical analyses. Compared to normal mucosa, 92% of the primary tumors (n = 60) showed reduced E-cadherin expression, suggesting that down-regulation of this cell adhesion molecule is a common early event in gastric tumorigenesis. No significant correlation was found between E-cadherin expression and tumor diameter, lymphatic vessel invasion, Borrmann classification, lymph node status, or manifest metastases. Although advanced tumors (tumor stage 3/4) showed a loss of E-cadherin-positive cells (< or = 50% cells/lesion, P = 0.0168), the most significant correlation was observed between low E-cadherin expression and cellular dedifferentiation (grading 3/4, P = 0.0001) and disintegration of tissue architecture (Lauren and WHO classifications, P = 0.0001). Low E-cadherin expression (< or = 50% cells/lesion) was associated with tumor recurrence (P = 0.0013) and mortality (P = 0.0246). E-cadherin expression in metastatic lesions (n = 58) also correlated with the degree of glandular differentiation (P = 0.0001). Significant correlation (rs = 0.686) was observed between E-cadherin expression in primary and metastatic lesions from individual patients (n = 39). However, while metastases derived from E-cadherin-negative tumors remained negative, those originating from E-cadherin-positive tumors frequently demonstrated increased levels of expression. Evaluation of multiple metastases in 11 patients revealed uniformly strong E-cadherin expression in liver metastases, suggesting a possible regulatory role of the microenvironment.

Meta-analyses of studies on bone marrow micrometastases: an independent prognostic impact remains to be substantiated.

PURPOSE: In 1997, the immunocytologic detection of isolated tumor cells in bone marrow, termed micrometastasis, will be optionally included in the tumor-node-metastasis (TNM) classification indicated M1(i). In the present meta-analyses, 20 studies, which included 2,494 patients, regarding the prognostic influence of a positive bone marrow micrometastases (BMM) status on relapse-free and/or overall survival were analyzed. MATERIALS AND METHODS: The literature search included the Medline and Current Contents bibliographic data bases from August 1980 to June 1997. The statistical evaluation considered the prognostic influence of the prevalence of micrometastatic cells in bone marrow on relapse-free and/or overall survival. The comparable effect estimate and its corresponding 95% confidence interval (CI) were calculated with the Mantel-Haenszel method using the originally published data of the retrieved studies. RESULTS: The presence of epithelial cells in bone marrow was detectable in all carcinoma types, with a median prevalence of approximately 35%. Fourteen of 20 studies found a positive correlation between positive BMM status and reduced relapse-free survival by univariate analysis, but only five of 11 studies confirmed positive BMM status as an independent predictor of short disease-free survival. Regarding overall survival, positive BMM status was identified univariately in five of 12 studies, but multivariately in only two studies, as an independent factor of poor survival. Despite the heterogeneity of the studies, calculation of the relative risk (RR) for reduced relapse-free survival was possible for breast cancer, which resulted in a Mantel-Haenszel RR (RR(MH)) of 1.34 (95% CI, 1.27 to 1.42). CONCLUSION: In conclusion, the results suggest that the prognostic impact of epithelial cells in bone marrow remains to be substantiated by further studies using standardized methodic protocols before its entrance in the TNM classification.

Epithelial tumor cells in bone marrow of patients with colorectal cancer: immunocytochemical detection, phenotypic characterization, and prognostic significance.

A monoclonal antibody (mAb) directed against the cytokeratin (CK) polypeptide no. 18 specifically expressed in cells derived from simple epithelia was used to detect epithelial tumor cells in bone marrow aspirates. Of 156 patients with colorectal carcinoma, 42 presented with cells at the time of primary surgery. The incidence of positive findings varied considerably with the size and the localization of the primary tumor, the involvement of regional lymph nodes, and the presence of clinically manifest metastases. Applying a sensitive double-staining procedure, we could demonstrate that epithelial cells in bone marrow showed a heterogeneic expression of receptors for epidermal growth factor (EGF-R) and transferrin (Tf-R) as well as of the proliferation-associated Ki67 antigen. Also human leukocyte antigen (HLA) class I antigens differed widely in their expression on the CK-positive cells. Clinical follow-up studies on 85 patients showed a significantly higher relapse rate in patients presenting with CK-positive cells in their bone marrow at the time of primary surgery. Twenty-three patients were monitored for the presence or absence of CK-positive cells in bone marrow over time. The majority of monitored patients (18 of 23) exhibited a constant pattern of immunocytochemical findings during the time of observation. Thus, the technique may be useful in identifying high-risk patients as well as in monitoring adjuvant therapeutic trials.

Monoclonal antibody therapy for resected Dukes' C colorectal cancer: seven-year outcome of a multicenter randomized trial.

PURPOSE: As previously shown, antibody treatment increased survival of patients with resected colorectal cancer of stage Dukes' C. Since the 5-year analysis was criticized because of the wide range (2.7 to 7.5 years) of follow-up time, we performed a 7-year analysis with only four of 189 patients monitored for less than 5 years. PATIENTS AND METHODS: A total of 189 patients with resected Dukes' C colorectal cancer were randomly allocated to infusions of a total of 900 mg 17-1A antibody, 500 mg postoperatively followed by 4 monthly doses of 100 mg (n=99), or to observation only (n=90). Primary end points were overall survival and disease-free interval. Patients were stratified by a dynamic randomization according to center, sex, location of tumor, number of affected lymph nodes, and preoperative carcinoembryonic antigen concentration. RESULTS: Randomization produced balanced distribution of risk factors. After 7 years of follow-up evaluation, treatment had reduced overall mortality by 32% (Cox's proportional hazard, P < .01; log-rank, P=.01) and decreased the recurrence rate by 23% (Cox's proportional hazard, P < .04; log-rank, P=.07). The intention-to-treat analysis gave a significant effect for overall survival (Cox's proportional hazard, P < .01; log-rank, P=.02) and disease-free survival (Cox's proportional hazard, P=.02; log-rank, P=.11 ). While distant metastases were significantly reduced (Cox's proportional hazard, P=.004; log-rank, P=.004), local relapses were not (Cox's proportional hazard, P=.65; log-rank, P=.52). This differential effect of 17-1A antibody on disseminated isolated tumor cells versus occult local satellites may explain the increased significance seen in the overall survival. CONCLUSION: The now-matured study shows that 17-1A antibody administered after surgery prevents the development of distant metastasis in approximately one third of patients. The therapeutic effect is maintained after 7 years of follow-up evaluation.

Prognostic significance of bone marrow micrometastases in patients with gastric cancer.

BACKGROUND: Monoclonal antibodies (mabs) against components of the cytoskeleton such as cytokeratins allow single disseminated epithelial carcinoma cells to be detected in the bone marrow. The aim of this study was to examine the prognostic relevance of these cells in patients with gastric cancer and to evaluate by multivariate analysis their predictive value compared with conventional risk factors. PATIENTS AND METHODS: A total of 1 x 10(6) cells from bone marrow aspirates were screened immunoctochemically for the presence and absolute number of disseminated tumor cells using mab CK2 to cytokeratin component no. 18. Patients were monitored prospectively for 30.6 +/- 15.2 months. RESULTS: Between one and 122 CK2-positive cells per 1 million mononuclear bone marrow cells were present in 95 of 180 patients (53%). A similar prevalence of 51% was found in curatively operated patients (55 of 109). Comparison with conventional prognostic risk factors showed a correlation of cell dissemination with pathohistologic tumor (pT) stage (P = .07) and Bormann classification (P = .022). Tumor-cell content in the bone marrow predicted disease-free and overall survival in curatively resected patients (P = .007 and P = .049, respectively). Multivariate analysis, which included established risk factors, showed that extent of tumor-cell dissemination was an independent prognostic parameter for disease-free survival in T1/2 tumors (P = .014; relative risk [RR], 1.84; 95% confidence interval [CI], 1.35 to 2.52), in intestinal type carcinomas according to Laurén (P = .008; RR, 1.62; 95% CI, 1.23 to 2.12), and in patients without lymph node involvement (P = .004; RR, 2.43; 95% CI, 1.22 to 4.82). CONCLUSION: Presence of disseminated tumor cells in bone marrow is indicative of systemic disease even in early-stage gastric cancer. The extent of tumor-cell presence in bone marrow correlates with prognosis in curatively resected patients. Therefore, a positive bone marrow finding may be a selection criteria for adjuvant treatment because of minimal residual tumor load.

Effect of different phenolic compounds on alpha-amylase activity: screening by microplate-reader based kinetic assay.

The inhibitory effect of different polyphenolic plant compounds on alpha-amylase activity was investigated in vitro. A kinetic assay was performed using 96-well-plates. Acarbose was used as positive control (IC50: 23.2 microM). Some of the tested compounds, occurring in plants traditionally used in anti-diabetic tea species, showed an inhibition of the enzyme in physiological concentrations, e.g. luteolin, tannic acid, and isochlorogenic acid.

Micrometastatic tumour cells in bone marrow of patients with gastric cancer: methodological aspects of detection and prognostic significance.

Monoclonal antibodies (Mab) are potent probes to identify individual tumour cells or small tumour cell clusters in bone marrow. In the present study, various antibodies directed against either cell surface or intracytoplasmic antigens of epithelial cells were assessed for their ability to detect such cells in bone marrow of patients with breast, colorectal and gastric cancer. According to the presented data, monoclonal antibodies against intracellular cytokeratin (CK) components are superior in terms of specificity and sensitivity to antibodies reacting with epitopes of the cell membrane. Using a monoclonal antibody against the cytokeratin polypeptide 18 in connection with the alkaline phosphatase anti-alkaline phosphatase detection system (APAAP), we could detect tumour cells in bone marrow of 34 out of 97 patients with gastric cancer examined at the time of primary surgery. The incidence of positive findings was correlated to established risk factors, such as histological classification and locoregional lymph node involvement. Clinical follow-up studies on 38 patients demonstrated a significantly increased relapse rate in patients presenting with CK-positive cells in their bone marrow at the time of primary surgery. Thus the described technique may help to identify patients with gastric cancer carrying a high risk of early relapse.

Expression of the CD6 T lymphocyte differentiation antigen in normal human brain.

Antigens shared by the immune and central nervous systems (CNS) have been described repeatedly. The present study reports the expression of the CD6 lymphocyte differentiation antigen in normal human brain evidenced by immunohistochemistry and Northern blot analysis. A panel of various anti-CD6 monoclonal antibodies (mabs) tested on serial cryostat sections identified CD6-positive cells randomly scattered in parenchyma of all examined brain areas. Northern blot analysis with a highly sensitive cRNA probe revealed a 3.1 kb CD6-specific mRNA in various brain regions, especially in basal ganglia and cortex cerebellum. Staining with mabs raised against different hematopoietic cell types, as well as hybridization with probes specific for the beta- and gamma-T cell receptor (TCR) chains support the notion that CD6 is expressed by original brain cells. The nature of the CD6-positive cell type and possible functions of shared antigens in immune and nervous systems are discussed.

Monoclonal antibodies against human astrocytomas and their reactivity pattern.

The establishment of hybridomas after fusion of X63-Ag8.653 mouse myeloma cells and splenocytes from BALB/c mice hyperimmunized against human astrocytomas is presented. The animals were primed with 5 X 10(6) chemically modified uncultured or cultured glioma cells. Six weeks after the last immunization step an intrasplenal booster injection was administrated and 3 days later the spleen cells were prepared for fusion experiments. According to the specificity analysis of the generated antibodies 7 hybridoma products (MUC 7-22, MUC 8-22, MUC 10-22, MUC 11-22, MUC 14-22, MUC 15-22 and MUC 2-63) react with gliomas, neuroblastomas and melanomas as well as with embryonic and fetal cells but do not recognize non-neurogenic tumors. The selected monoclonal antibodies (McAbs) of IgG1 and IgG2a isotypes are not extensively characterized but these antibodies have been demonstrated to be reactive with a panel of glioma cell lines with varying patterns of antigen distribution. Using the McAbs described above and a series of cryosections of glioma biopsies and paraffin sections of the same material as well as glioma cultures established from these, variable antigenic profiles among glioma cell populations could be demonstrated. From these results it is evident that there is not only a distinct degree of antigenic heterogeneity among and within brain tumors, but also that the pattern of antigenic expression can change continuously. Some of the glioma associated antigens recognized by the selected antibodies persist after fixation with methanol/acetone and Karnovsky's fixative and probably are oncoembryonic/oncofetal antigen(s). The data suggest that the use of McAbs recognizing tumor associated oncofetal antigens in immunohistochemistry facilitates objective typing of intracranial malignancies and precise analysis of fine needle brain/tumor biopsies in a sensitive and reproducible manner.

[Detection of tumor cells in bone marrow: a deciding aid for adjuvant therapy in node negative patients with breast cancer. Concept for a multicenter study and results of the pilot phase]. / Tumorzellnachweis im Knochenmark: Entscheidungshilfe zur adjuvanten Therapie bei nodal-negativen Patientinnen mit Mammacarcinom. Konzept einer Multicenterstudie und Ergebnisse der Pilotphase.

In node-negative breast cancer some 30% of patients will suffer a tumor relapse, despite primary curative therapeutic intervention. An adjuvant therapy is therefore in discussion, especially in presence of risk factors. Immunocytochemical staining of cytokeratin-positive cells in bone marrow aspirates with monoclonal antibodies offers a chance to detect tumorcell dissemination at an early stage of single tumor cells. In 103 consecutive patients 50% showed a positive bone marrow aspirate, in node negative patients still 34%. Based on the literature and tumor biology this method may be valid in selecting node-negative breast cancer patients for adjuvant therapy. In a prospective multi-center trial the prognostic value will be evaluated in regard to other prognostic factors. Additionally the benefit of an adjuvant therapy will be studied in a randomized prospective trial.

[Detection of disseminated tumor cells in bone marrow--currently of no practical therapeutic value]. / Nachweis disseminierter Krebszellen im Knochenmark, Als Prognosefaktor für die Praxis noch nicht therapierelevant.

Development of metastases in cancer patients is usually due to tumour cells seeding from the primary. These disseminated cells can be detected in blood or bone marrow with the aid of immunocytochemical methods. The clinical significance of this is, however, still controversial. With the aim of determining the prognostic value of disseminated tumour cells, a meta-analysis of 20 publications reporting results based on data collected from a total of 2494 breast cancer patients, was carried out. The outcome of the meta-analysis was that 14 of the 20 studies provided evidence suggesting positive bone marrow findings to be an unfavorable prognostic factor. Five out of twelve studies provided multivariate analytic evidence of an impact of bone marrow status on recurrence-free survival. In five out of twelve studies, a univariate analysis showed a positive bone marrow finding to correlate significantly with overall survival, while a multivariate analysis found such a correlation in only two out of six studies. Owing to a lack of standardization, the results of the individual studies are not directly comparable. Against this background it is too early to say whether the detection of disseminated tumour cells in the bone marrow can be used as a prognostic factor with an impact on therapeutic strategies.

[Attempts to produce human monoclonal antibodies to melanoma using the cervical lymph nodes]. / Versuche zur Herstellung menschlicher monoklonaler Antikörper gegen Melanome unter Verwendung zervikaler Lymphknoten.

Due to their specificity, constant properties and virtually unlimited supply monoclonal antibodies have given an important stimulus to almost every field of biomedical research within the last 10 years. The generation of mouse monoclonal antibodies includes immunisation of mice followed by fusion of mice spleen cells with a murine myeloma cell line. With this procedure hybridomas secreting monoclonal antibodies of a predefined specificity can be obtained. For three major reasons we worked on the establishment of human hybridomas secreting specific antibodies: human antibodies are less immunogenic when used for diagnostic or therapeutic purposes, only human monoclonal antibodies allow the analyses of the human B cell repertoire, there is evidence that human monoclonal antibodies recognise epitopes different from those seen by murine monoclonal antibodies. Therefore, we set out to generate human B cell hybridomas by cell fusion using the human lymphoblastoid B cell line Wi-L2-729 HF2 and lymphocytes from melanoma patients. The lymphocytes were isolated from tumour-draining cervical lymph nodes, stimulated with pokeweed mitogens plus the autologous tumour cells in an enriched tissue culture medium and fused in the presence of polyethylene glycol. Supernatants of hybridomas were screened in a single cell immunosorbent assay with either autologous melanoma cells or established melanoma cell lines fixed to the bottom of Terasaki plates or on cytospin preparations of these cells using the immunoperoxidase staining procedure. We could demonstrate that the tumour draining lymph nodes of these melanoma patients contained B lymphocytes capable of producing antibodies reacting with the tumour cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Palliative cytoreduction in refractory acute leukemia: a retrospective study of 57 adult patients.

The efficiency and toxicity of treatment regimens for nonintensive cytoreduction in 57 outpatients with refractory acute leukemia (mean age 56 years, 51 AML, six ALL/AUL) were retrospectively studied. Seventeen patients received one treatment regimen, 19 patients two treatment regimens, and 21 patients three or more treatment regimens. The treatment regimens analyzed were 6-thioguanine p.o. (daily) (T), 6-thioguanine p.o. (4-7 days/week) + cytarabine s.c./i.v. (once a week) (T+C), 6-mercaptopurine p.o. (daily) (MP), 6-mercaptopurine p.o. (daily) + methotrexate p.o./i.v. (once a week) (MP+MTX), etoposide p.o. (daily) (E), and mitoxantrone i.v. (M). The median leukocyte count was higher for M (73 x 10(9)/l) than for the other treatment regimens (T: 27 x 10(9)/l, T+ C: 37 x 10(9)/l, MP: 24 x 10(9)/l, MP + MTX: 30 x 10(9)/l, E: 31 x 10(9)/l). A cytoreduction >50% in the peripheral blood was achieved by T in 11/19, by T+C in 7/11, by MP in 5/8, by MP+MTX in 3/6, by E in 3/4, and by M in 16/22 patients. The period of cytoreduction was regarded as the duration of response - T: median 53 days, range 5-98; T+C: median 61 days, range 14-226; MP: median 37 days, range 4-192; MP + MTX: median 58 days, range 36-59; E: median 121 days, range 26-159; M: median 39 days, range 8-78. T and T + C were well tolerated by all but three patients (stomatitis, diarrhea, WHO grade 2). MP was accompanied by a rise of transaminases (WHO 1-3) in 5/6 patients. E led to stomatitis (WHO 1,2) in 4/5 and M to nausea/vomiting (WHO 1,2) in 5/22 and to stomatitis (WHO 2) in 4/22 cases. The mean survival time after start of palliative cytoreduction was 16 weeks (2-65). In summary, 6-thioguanine +/- cytarabine was best tolerated with effective but in oral monotherapy - often protracted cytoreduction in 60% of patients. Mitoxantrone showed tolerable side effects and potent cytoreduction in 73% of patients even after ineffective palliative pretreatment. Palliative cytoreductive therapy does not reduce the quality of life and can prevent complications of significant leukocytosis in refractory acute leukemia.

High expression of a Lewis(x)-related epitope in gastric carcinomas indicates metastatic potential and poor prognosis.

BACKGROUND & AIMS: The acquisition of metastatic potential is accompanied by phenotypic changes. The aim of this study was to identify those changes that may lead to the development of new antimetastatic strategies in gastric cancer. METHODS: A new murine monoclonal antibody showing differential reactivity with benign and malignant gastric tissues was isolated. The expression pattern of the recognized 2B4 antigen was determined with immunohistochemistry, and the antigen was analyzed by immunoprecipitation and enzyme digestion. Its prognostic impact in gastric cancer was tested in univariate and multivariate analyses. RESULTS: In gastric mucosa, 2B4 expression was significantly reduced on mucosal glands in the presence of an inflammatory infiltrate and could be modulated in vitro by exposure to interferon alfa and gamma and phorbol esters. Twenty-eight percent of the primary gastric carcinomas showed high levels of 2B4. This correlated significantly with clinicopathological parameters of advanced disease (tumor size of > 50 mm, M1 stage, and UICC stage IIIB/IV). In multivariate analysis, high 2B4 expression was found to be a new, independent parameter of poor prognosis. The 2B4 monoclonal antibody was shown to react with the trisaccharide Gal beta 1-->4(Fuc alpha 1-->3)GlcNAc, i.e., Lewis(x). CONCLUSIONS: High levels of the Lewis(x)-related epitope defined by MAb 2B4 in primary gastric carcinomas is an independent parameter of poor survival.