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Biomedical subjects

M E Toubert

Publications and source records attributed to M E Toubert.

At least 37 records · Page 2Linked to original sources

[Cervico-mediastinal recurrences of differentiated thyroid cancers: value of MRI].

AIM: The aim of this study was to evaluate the ability of MRI to detect recurrent differentiated thyroid carcinomas developed in the neck or the upper mediastinum. RESULTS: MRI was performed in 25 patients, and was compared in 5 cases with surgery. In 20 cases it was compared with I-131 scintigraphy (100 mCi in 14 cases and 5 mCi in 6 cases). The sensibility, specificity and overall accuracy of MRI was respectively: 100%, 66.6%, 82.6%. COMMENTARY: MRI is a good technique to detect recurrent thyroid carcinomas. It is specially interesting to investigate patients with a biological suspicion of recurrence and a negative scintigraphy. Mediastinal localisations that cannot be detected by US can be detected by MRI.

Adult↗

Tumour-associated trypsin inhibitor and renal cell carcinoma.

In the absence of a specific marker for renal cell carcinoma (RCC), we evaluated the tumour-associated trypsin inhibitor (TATI) in patients with RCC. Between November 1990 and November 1993, 63 patients with RCC and 23 patients with benign renal disease underwent a competitive radioimmunoassay of TATI. The cutoff value was defined on a series of serum samples of 96 healthy subjects (normal n < 20 micrograms/l, then 25 micrograms/l after April 1993). We related the value of TATI to the tumour stage and compared the sensitivities of TATI and other markers (CEA, CA 15-3, CA 125, CA 19-9, ferritin). In 24 patients the TATI assay was repeated 3-12 months after radical nephrectomy. 15 patients with benign disease had a normal value of TATI (specificity: 65%). 44 of the 63 patients had a value of TATI above the cutoff point (sensitivity: 69%). Sensitivities of CEA, CA 15-3, CA 125, CA 19-9 and ferritin were 5, 10, 13, 5, 35%, respectively. The TATI value was correlated with the stage of the disease. Among the 15 patients without metastasis, the mean preoperative value was 112 micrograms/l (14-760) versus 46 micrograms/l (24-180) postoperatively. In the 9 patients with metastasis, the preoperative mean value was 100 micrograms/l (20-434) versus 240 micrograms/l (22-544) postoperatively. TATI showed a better sensitivity than other markers for RCC but its specificity is limited. Nevertheless it can be useful for a postoperative follow-up. TATI remains one of the best serum markers for RCC.

Biomarkers, Tumor↗

Hematopoietic growth factor expression and ATRA sensitivity in acute promyelocytic blast cells.

Acute promyelocytic leukemia (APL) is a homogeneous subgroup of acute myeloid leukemias (AMLs) characterized by the presence of the t(15,17) translocation and the resulting promyelocytic myeloid leukemia/retinoic acid receptor alpha (PML/RAR alpha) fusion proteins. To date APL is the only AML that is sufficiently sensitive to all-trans retinoic acid's (ATRA) differentiating effect. In vivo ATRA alone achieves complete remission in most APL patients. However, failure or partial responses are observed and the molecular basis of the absence of ATRA response in these patients has not been determined. To gain insights in the cell growth and differentiation of APL cells, expression of hematopoietic growth factors (HGF) shown to be produced by leukemic cells (interleukin-1 beta [IL-1 beta], IL-6, tumor necrosis factor alpha (TNF alpha), granulocyte colony-stimulating factor [G-CSF], granulocyte-macrophage colony-stimulating factor [GM-CSF], and IL-3) was studied in 16 APL samples. Twelve APL cases expressed IL-1 beta, IL-6, and TNF alpha, but not G-CSF, GM-CSF, and IL-3. These cases achieved complete remission with ATRA therapy. The four remaining patients (either TNF alpha negative or G-CSF, GM-CSF or IL-3 positive) did not achieve complete remission with ATRA. In all cases, in vivo response to ATRA therapy was correlated to the in vitro differentiation effect of all-trans retinoic acid 10(-6) mol/L. Thus, ATRA differentiation induction was strongly correlated to the HGF expression (P < .0001). These results suggest that the presence or absence of HGF's expression by APL cells may contribute to the therapeutic effect of ATRA in this disease.

Cell Differentiation↗

Serum tissue polypeptide antigen (S-TPA) in bladder cancer as a tumor marker. A prospective study.

BACKGROUND: Tissue polypeptide antigen (TPA) is a differentiation and a proliferation tissue marker of non-squamous epithelia. Increased urinary and serum TPA (S-TPA) levels were found in some patients with invasive bladder cancer. The authors report the results of a prospective study evaluating the role of serum TPA (S-TPA) in bladder carcinoma. METHODS: S-TPA concentrations were measured by radioimmunoassay in 53 patients with invasive bladder tumor before treatment, at the end of treatment, and during follow-up. The upper normal limit of the test was set at 80 UI/ml. RESULTS: With a specificity of 100%, the diagnostic sensitivity of the test was 54.7%. S-TPA was increased in 88% of patients with N1 + N2 disease compared with 38.8% of the patients with N0 disease (P = 0.01) and in 100% of patients with metastatic disease and 48% of patients with nonmetastatic disease (P = 0.01). S-TPA was increased in 23% of patients with total macroscopic debulking and in 68% of patients with persistent macroscopic disease (P = 0.004). For patients staged N0 M0, no statistical correlation between S-TPA level and debulking by transurethral resection (TUR) was found (P = 0.15). In the subset of patients with normal pretherapeutic S-TPA levels, 75% achieved a complete response, compared with 44.8% of the patients with initial elevated S-TPA levels (P = 0.04). However, there was no statistically significant relationship between pretherapeutic S-TPA levels and immediate response to treatment according to the stratification for tumor volume after initial debulking by TUR. For a mean follow-up of 15 months +/- 7 months, median survival time and 1-year survival rates were studied in the subset of patients with limited disease (N0 M0) according to the pretherapeutic S-TPA levels. The median survival time was not reached, and the 1-year survival rate was 80% when the initial S-TPA level was normal; these were 10 months and 44%, respectively, when the S-TPA level was high (P < 0.01). Among the 31 patients who achieved a complete response, 9 experienced a relapse, with an increase of the S-TPA level in 8 patients. CONCLUSIONS: The S-TPA level is correlated with initial tumor volume. It appears to be a prognostic factor and a valuable parameter for follow-up.

Biomarkers, Tumor↗

Modulation of IL-8, IL-1 beta, and G-CSF secretion by all-trans retinoic acid in acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is a homogeneous subgroup of acute myeloid leukemias (AML) characterized by the presence of the t(15;17) translocation and the resulting PML/RAR alpha fusion proteins. To date APL is the only AML which is sufficiently sensitive to all-trans retinoic acid (ATRA) differentiating effect. We have recently reported that APL express and secrete hematopoietic growth factors (HGF) such as IL-1 beta, TNF alpha, and IL-6. In vivo ATRA alone allows achievement of complete remission in APL patients. One of ATRA therapy's drawbacks is the increase of peripheral blast cells often associated with the ATRA leukocyte activation syndrome. To determine if this specific side-effect was linked to an increase of HGF release by APL cells, we studied the modulation of cytokine production by APL cells, we studied the modulation of cytokine production by APL samples (n = 12) before and after incubation with ATRA. ATRA failed to modulate TNF alpha, IL-6 or GM-CSF secretion levels; however, IL-8 levels decreased in 11 cases, and in four cases up-regulation of IL-1 beta and G-CSF protein expression was observed. These modulations were found to be linked to ATRA sensitivity as ATRA failed to modulate cytokine production in non-APL cells (n = 8). Interestingly, the increase of IL-1 beta and G-CSF production in the presence of ATRA was highly correlated to an increase in APL cell count in vitro and in vivo hyperleukocytosis, resulting in fatal outcome. IL-1 beta, TNF alpha, IL-6, and IL-8 are known to be implicated in leukocyte activation. The results of this study suggest that ATRA-induced hyperleukocytosis and ATRA leukocyte activation syndrome in APL may be inherent to the secretion of specific hematopoietic growth factors by the APL cells.

Blotting, Northern↗

Identifying abnormal parathyroid glands in the thyroid uptake area using technetium-99m-sestamibi and factor analysis of dynamic structures.

UNLABELLED: A rapid (25 min) single tracer scintigraphic method to localize parathyroid gland abnormalities was evaluated in 24 patients with hyperparathyroidism. METHODS: Scintigraphy was performed with 99mTc-sestamibi prior to surgery. A 25-min dynamic series centered on the neck was acquired immediately after injection of 99mTc-MIBI. Two planar static views were obtained after 1 and 2 hr. To identify abnormal parathyroid tissue in the thyroid uptake area, a factor analysis of dynamic structure (FADS) was applied to the dynamic acquisition. The results were compared to the analysis of the two planar static views. RESULTS: FADS demonstrated abnormal uptake of the tracer in the thyroid area for 26 of the 31 parathyroid glands found to be abnormal at surgery (5/6 adenomas, 21/25 hyperplastic glands). In three cases, FADS demonstrated parathyroid uptake despite the absence of parathyroid tissue at surgery. FADS revealed as specific and more sensitive than the visual analysis of the two static views, since only 13/30 glands were still visible after 1 hr, and 5/26 after 2 hr. Furthermore, a study with two static views was found to be less sensitive for the detection of hyperplastic glands. CONCLUSION: FADS99mTc-MIBI is performed in less time than existing scintigraphic protocols. It is a promising method to detect abnormal parathyroid glands in the cervical area with a single tracer.

Adenoma↗

Induction of high-affinity GM-CSF receptors during all-trans retinoic acid treatment of acute promyelocytic leukemia.

Differentiation of normal myeloid cells is accompanied by the increase of high-affinity GM-CSF receptors necessary for progenitor proliferation/differentiation and mature neutrophil function. All-trans retinoic acid (ATRA) induces terminal differentiation of acute promyelocytic leukemia cells (AML3 subtype). We report in this study that AML3 cells, like other AML subtypes, harbor high-affinity GM-CSF R (n = 138.3 +/- 69.3 sites/cell, Kd = 76.9 +/- 68.8 pM). In all cases, incubation with ATRA induces either an increase in the number of affinity of GM-CSF R (n = 212.7 +/- 116.2 sites/cell, Kd = 43.2 +/- 22.5 pM). The data presented show that modulation of GM-CSF receptors cells is correlated to the degree of ATRA-induced granulocytic differentiation but not to increased cell growth.

Cell Differentiation↗

[Treatment of polycythemia with 32P with or without hydroxyurea maintenance therapy. Preliminary results in 237 elderly and high vascular risk subjects studied since 1980].

Between 1980 and 1992, 237 polycythaemic patients aged 65 or more, or with high vascular risk factors were treated with 32P according to a protocol using, or not, maintenance therapy with low-dose hydroxy-urea (500 mg/day). The present follow-up covers 1448 years/patient. Maintenance therapy was seldom discontinued because of blood toxicity or gastrointestinal intolerance, but it was stopped in 20 percent of the cases because monitoring was difficult in very old patients. Maintenance therapy reduced the mean annual 32P dose by at least 50 percent. However, the actual risk of malignant blood diseases (myelodysplasia, acute leukaemia, lymphoma) was similar in the two arms of the protocol: 14 percent at the 10th year. Compared with the French population of the same age-groups, there was no excess of epithelial cancers in both arms. Maintenance therapy did not control platelet counts perfectly. The risk of severe vascular events was identical in both arms; probably no higher than expected at that age and significantly lower than in previously published data. The actuarial survival curves in both groups showed a 50 percent survival of about 11 years, i.e. very near to that of the reference French population (12.5 years) of similar sex and age.

Age Factors↗

The 'euthyroid sick syndrome': incidence, risk factors and prognostic value soon after allogeneic bone marrow transplantation.

We studied the incidence of thyroid function abnormalities observed soon after allogeneic bone marrow transplantations (BMT) and their predictive value on the overall prognosis. Free serum thyroxine, free serum triiodothyronine, total serum reverse triiodothyronine and serum thyrotropin levels were systematically measured in 78 patients before and 3 months after BMT. 41 (52%) had normal hormone levels and 37 (48%) had abnormal ones, among whom four (5%) had peripheral compensated hypothyroidism and 33 (43%) were described as having 'euthyroid sick syndrome' (low thyroxine state, or low T3 syndrome). Two factors strongly influenced the appearance of thyroid abnormalities: steroid dose at the time of thyroid function testing, and age (< or = 16 years/ > 16 years). Among the younger patients, 21 had no thyroid abnormalities, while five did. Among the older patients, 20 had no thyroid abnormalities, while 32 did (P < 0.001). The occurrence of thyroid abnormalities seemed to influence survival strongly, since the 30-month projected survival time was 83% for patients without abnormalities whereas it was 49% for patients with an abnormal profile (P < 0.001). In conclusion, evidence obtained among our population reveals that euthyroid sick syndrome indicates a poor prognosis and that it is very important to monitor thyroid hormone levels (particularly free hormones) soon after allogeneic BMT and regularly thereafter.

Adolescent↗

[Current data on GM-CSF (Granulocyte-Macrophage Colony Stimulating Factor) in acute myeloid leukemia].

GM-CSF (Granulocyte-Macrophage Colony Stimulating Factor) activates neutrophil, eosinophil, granular, and macrophage precursors through binding to specific receptors. GM-CSF receptor is a member of the "cytokine receptor superfamily", which displays a particular transmembrane structure. It is expressed in small amounts on normal mature blood or medullary cells, with a high affinity. On acute myeloid leukemia blasts (18 patients), our results agree with the review of the literature: GM-CSF receptors are in small amounts, of two types (high and low affinity), with no relation to the FAB classification of leukemias.

Colony-Stimulating Factors↗

Histological and urinary reactivity of monoclonal antibody 1BE12 in bladder carcinoma. Purification of the antigen from urine.

We have previously reported the production of monoclonal antibody (MAb) 1BE12, which recognizes a glycoprotein in breast-cancer cells. In the present work, 1BE12 reactivity was tested by immunohistochemistry in bladder carcinoma (92 cases) and in non-tumoral bladder samples (15 cases). In 71% of bladder tumors, more than 30% of cells were intensely stained by 1BE12. The percentage of reactive cells was higher in cancers invading the muscle than in more superficial tumors (p = 0.039). In non-tumoral bladder, immuno-staining, when present, was usually confined to the superficial layers with a low number of cells stained (less than 30%) in 13/15 cases. Slot blots, performed on urine samples from 43 bladder-cancer patients and 21 healthy controls, were quantified by densitometry scanning. We found higher optical density (OD) values in urine from muscle-invasive-cancer patients than in urine from more superficial tumors and healthy controls, with a significantly different distribution (p = 0.005). The urinary antigen was detected by immunoblotting with 1BE12 as high-molecular-weight species (greater than 150 kDa). The reactive glycoprotein could thus be purified by immunoaffinity and FPLC filtration from the perchloric-acid-soluble fraction of urine from patients with invasive bladder carcinoma. The availability of purified antigen will allow us to quantitate our assay, in order to evaluate its potential use as a prognostic indicator in bladder-cancer patients.

Antibodies, Monoclonal↗

The site of platelet destruction in thrombocytopenic purpura as a predictive index of the efficacy of splenectomy.

The significance of the site of platelet sequestration in determining the indication for splenectomy in idiopathic thrombocytopenic purpura (ITP) is a controversial subject. However, most of the negative conclusions are based on 51chromium labelling of homologous platelets. We report here the results of an analysis of 222 cases in which the kinetic study of 111indium-oxinate-labelled autologous platelets was performed under homogeneous technical conditions. 103 of these patients subsequently underwent splenectomy. This study demonstrates that the site of platelet sequestration in active ITP constitutes a variable independent of the patient's age, history of the disease and its severity (platelet count, lifespan). The sequestration site is a good predictive element of the short-term efficacy of splenectomy (71/76 cases with splenic sequestration obtained a platelet count exceeding 100 x 10(9)/l versus 7/13 cases with mixed sequestration and 1/14 cases with hepatic sequestration), and the long-term results (6 months to 5 years after splenectomy) do confirm the clinical value of this study.

Adolescent↗

Granulocytic colony-stimulating factors (G-CSF and GM-CSF) in the treatment of adult acute myeloid leukemia.

Large randomized trials have shown that granulocytic colony-stimulating factors (G-CSF and GM-CSF) may be interesting in vivo in promoting neutrophil recovery after high-dose myelosuppressive therapy in some clinical settings. However, any beneficial effect on survival was not yet demonstrated. Granulocytic CSFs act as growth and viability factors on myeloid leukemic cells and their use in acute myeloid leukemias (AML) is theorically not without risk. Paradoxically, these CSFs will maybe be usefull in the future as a part of AML treatment. First, the high early mortality rate in elderly AML patients after intensive chemotherapy should allow a demonstration of a CSF-induced improvement of survival. Secondly, GM-CSF should increase the efficacy of cell cycle dependent cytotoxic drugs based on recruitment of quiescent leukemic cells. Third, granulocytic CSFs should be used to induce programmed cell death in myeloid leukemic cells.

Acute Disease↗

[Screening for cancer of the prostate using prostate-specific antigen].

Systematic screening for prostate cancer was carried out in 600 men over 50 years of age by the industrial medicine departments of four big companies in the Paris region. The exploratory methods included prostate specific antigen (PSA) and prostatic acid phosphatase (PAP) assays, rectal palpation and two-dimensional transrectal ultrasonography. Biopsy of the prostate was performed either when the PSA level was above 5 ng/ml or when rectal palpation gave suspicious results, or when ultrasonography showed abnormal images. A total of 93 biopsies were performed, and 18 cases of cancer were detected. Eleven of these 18 patients underwent radical prostatectomy. The PSA assay, with an accepted limit of 5 ng/ml, detected 17 out of 18 cancers but was not very specific. The PAP assay had low sensitivity (only 5 positive results). Combined PAP assay and rectal palpation provided high sensitivity and good specificity. Transrectal ultrasonography was helpful only to determine the site of biopsy and the distribution of the lesions.

Acid Phosphatase↗

[Detection of cancer of the prostate. A study of 600 cases].

A free screening consultation for carcinoma of the prostate was proposed to men over the age of 50 years working in different companies in the areas of Paris. This consultation included a digital rectal examination, a blood test for determination of serum acid phosphatase and prostatic specific antigen, and two dimensional trans-rectal ultrasonography of the prostate. 600 patients were seen. 575 were evaluable. Prostate biopsy was recommended in 152 men. Ninety-three prostate biopsies were performed. Eighteen prostatic cancers and 1 urothelial cancer invading the prostate were detected with an overall incidence of prostate cancer of 3.1%. Radical prostatectomies were performed in 10 of the 18 patients with a prostate cancer. Sensitivity of digital rectal examination ultrasonography and PSA were respectively 42.8%, 47.3% and 68.4% with an abnormal serum PSA level defined as being greater than 5 ng/ml. The predictive value of a positive ultrasonography (18.7%) contrasts with the predictive value of a positive digital rectal examination (30.7%) and serum PSA (30%). Digital rectal examination and determination of serum prostatic specific antigen seem to be the most useful tests for mass screening of prostate cancer. Transrectal ultrasonography is very useful for guided prostatic biopsy and for a better topographic evaluation of the tumor.

Aged↗

Radioimmunoassay of erythropoietin: analytical performance and clinical use in hematology.

We report here the performance of a recently commercialized radioimmunoassay kit for determining erythropoietin (EPO) in serum or plasma. The lower detection limit of the method was 3 U/L. Precision, analyzed by the variation coefficients between different assay runs and in the same experiment, was always less than 10%; accuracy was assessed by recovery and dilution tests. In anemic patients (hematocrit 18-39%), the concentration of EPO was logarithmically related to hematocrit. A relatively large dispersion of the results was noted, as reported by others with various RIAs. Patients with severe renal failure demonstrated a very low EPO value, whatever the degree of their anemia. In some chronic anemias resulting from malignancy, EPO concentrations were also relatively low. In the polycythemia vera group, the EPO mean was below normal for greater than 95% of the patients, whatever their clinical stage (first evaluation, relapse, or remission). In contrast, 91% of the patients with pure erythrocytosis had a normal or increased EPO value, even when the etiology was unknown. Measurement of EPO concentration may be useful for the clinical differentiation of myeloproliferative disorders and, subsequently, for their prognosis and choice of treatment.

Erythropoietin↗