Dealing with dry waste disposal issues associated with 177mLu impurities: a long-term challenge for nuclear medicine departments.

PURPOSE: A strategy for management of radioactive waste associated with 177Lu-dotatate (Lutathera®) treatments was established in our institution, based on predicted storage times of 3-5 years extrapolated from the results of a 2-year measurement study. The aim of this work was to validate this strategy by identifying contaminants and confirming disposal based on the clearance level twice-the-background was within expected time frames. METHODS: We conducted a prospective series of measurements of radioactive waste associated with the first 65 treatments administered. Sequential measurements of the first 45 vials used were performed on a dose calibrator to identify contaminants. Exposure rates in contact were monitored with a dose ratemeter on a 6-monthly basis for all waste stored: 46 empty vials, 19 vials partially used and 61 biohazard containers. RESULTS: Initial median activity of the first vials used was 118 MBq [4-4188 MBq]. For each vial, the decay curve of activity obtained was adjusted to a bi-exponential model. The major component, representing 99.7% of the activity, has a median half-life of 6.6 days [5.7-7.2 days] corresponding to 177Lu. The second, representing only 0.3% of the activity and having a median half-life of 152 days [104-205 days] corresponding to 177mLu, determines necessary storage times. Partially used vials can be disposed of after 5 years, other waste after 3 years. Compliance with the regulatory clearance level is achieved within expected time frames. CONCLUSION: Although only present as traces, 177mLu associated with the direct production route results in major radioactive waste disposal issues for hospitals. Availability of radiopharmaceuticals without impurities appears to be crucial for an expanding use of targeted radionuclide therapy.

Comparison between tumour metabolism derived from 18F-FDG PET/CT and accurate cytogenetic stratification in newly diagnosed multiple myeloma patients.

BACKGROUND: 18F-fluorodeoxyglucose positron emission tomography integrated with computed tomography (18F-FDG PET/CT) is a useful tool for baseline staging in newly diagnosed multiple myeloma (MM) but also for prognostic stratification. This monocentric retrospective study aimed at examining the relation between baseline tumour metabolism assessed by 18F-FDG PET/CT and linear predictor (LP) score, a new cytogenetic stratification score. METHODS: From March 2012 to March 2019, 57 patients with newly diagnosed MM addressed to our institution for baseline 18F-FDG PET/CT were included. LP score was determined on systematic iliac crest bone marrow samples. Obtained on CD138-sorted bone marrow plasma cells, this recent composite cytogenetic stratification is a 6-marker based weighted score using fluorescence in situ hybridization (FISH) ± single nucleotide polymorphism (SNP) arrays. We compared quantitative metabolic parameters and LP score using a Kruskal-Wallis test and visual suspicion of diffuse bone marrow involvement (DBI; based on hepatic background as threshold of positivity) and cytogenetic data using a Chi-squared test. RESULTS: The distribution of total metabolic tumour volume (TMTV) and total lesion glycolysis (TLG) values among the three LP score categories was almost stochastic, with no significant association (P=0.70). Additionally, no significant association between TMTV/TLG and any of the six cytogenetic abnormalities included in LP score calculation. A significant association was found between visual high suspicion of DBI and LP score (P=0.036), and between this visual parameter and the presence of 1q gain (P=0.049). CONCLUSIONS: There is no significant association between quantitative metabolic parameters assessed with 18F-FDG PET/CT and LP score in patients with newly diagnosed MM, suggesting a potential complementarity of these biomarkers for prognostic stratification. A significant association was found between high visual suspicion of DBI and LP score.

[Factors influencing platelets labelling with indium-111 oxine]. / Facteurs influençant le marquage des plaquettes à l'oxinate d'indium-111.

Autologous indium-111 labelled platelets can be used for kinetic studies in patients with autoimmune thrombocytopenic purpura [AITP]. The objective of this study was to evaluate some biological and clinical factors influencing the labeling efficiency. METHODS: We studied incubation media (Plasma media [MP] or dry media [MS]), platelet concentration [NP], mean platelet volume [VPM], hemoglobin level and pathology associated with AITP. RESULTS: This was a retrospective study of 93 platelets labelling (43 in MS and 50 in MP), 38 primary AITP (41%) and 55 secondary AITP (59%). The labeling efficiency was 72% (78% in MS versus 53% in MP; p < 0.0001). The labeling efficiency was correlated with VPM (p = 0.0004), NP (p = 0.03), hemoglobin level (p = 0.037) and type of AITP (p = 0.0036). The incubation medium, hemoglobin level and type of the AITP have an independent predictive value on the labeling efficiency. CONCLUSION: These data confirm the influence of the incubation medium on the labeling efficiency and identify two other predictive criteria, hemoglobin level and type of AITP.

Impact of contouring methods on pre-treatment and post-treatment dosimetry for the prediction of tumor control and survival in HCC patients treated with selective internal radiation therapy.

INTRODUCTION: The aim of this study was to evaluate the impact of the contouring methods on dose metrics and their predictive value on tumor control and survival, in both situations of pre-treatment and post-treatment dosimetry, for patients with advanced HCC treated with SIRT. METHODS: Forty-eight patients who underwent SIRT between 2012 and 2020 were retrospectively included in this study. Target volumes were delineated using two methods: MRI-based contours manually drawn by a radiologist and then registered on SPECT/CT and PET/CT via deformable registration (Pre-CMRI and Post-CMRI), 99mTc-MAA-SPECT and 90Y-microspheres-PET 10% threshold contouring (Pre-CSPECT and Post-CPET). The mean absorbed dose (Dm) and the minimal absorbed dose delivered to 70% of the tumor volume (D70) were evaluated with both contouring methods; the tumor-to-normal liver uptake ratio (TNR) was evaluated with MRI-based contours only. Tumor response was assessed using the mRECIST criteria on the follow-up MRIs. RESULTS: No significant differences were found for Dm and TNR between pre- and post-treatment. TNR evaluated with radiologic contours (Pre-CMRI and Post-CMRI) were predictive of tumor control at 6 months on pre- and post-treatment dosimetry (OR 5.9 and 7.1, respectively; p = 0.02 and 0.01). All dose metrics determined with both methods were predictive of overall survival (OS) on pre-treatment dosimetry, but only Dm with MRI-based contours was predictive of OS on post-treatment images with a median of 23 months for patients with a supramedian Dm versus 14 months for the others (p = 0.04). CONCLUSION: In advanced HCC treated with SIRT, Dm and TNR determined with radiologic contours were predictive of tumor control and OS. This study shows that a rigorous clinical workflow (radiologic contours + registration on scintigraphic images) is feasible and should be prospectively considered for improving therapeutic strategy.

[Effect of obesity, age and gender on glomerular filtration rate measured in normal adults]. / Influence de l'obésité, de l'âge et du sexe sur le débit de filtration glomérulaire mesuré chez l'adulte normal.

The aims of this study were to assess the dependence of glomerular filtration rate (GFR) on age and gender and to produce reference data for the interpretation of 51Cr-EDTA GFR measurements in adults. METHODS: This was a retrospective study of 120 live kidney donors (75 females, 45 males). GFR was evaluated from 51Cr-EDTA plasma clearance using blood samples taken at 3, 4 and 5 hours. The slope-intercept GFR was corrected for body surface area using the Dubois & Dubois and for the fast exponential using the Brochner-Mortensen equation. Scatter plot of DFG against age in live kidney donors was plotted and the 98% range limits have been defined. RESULTS: The median GFR obtained for kidney donors was 88 mL/min/1.73 m2 [68-130]. No significant difference with gender was found. 51Cr-EDTA clearance was strongly correlated with patient age (r = - 0.62, P < 0,0001). GFR decreased by approximately 8 mL/min/1.73 m2 per decade. Based on these results, a nomogram for GFR is presented. CONCLUSION: The interpretation of GFR requires age-adjusted normal values. These standards need not be adjusted to the patient's sex or BMI.

Transarterial Radioembolization of Hepatocellular Carcinoma, Liver-Dominant Hepatic Colorectal Cancer Metastases, and Cholangiocarcinoma Using Yttrium90 Microspheres: Eight-Year Single-Center Real-Life Experience.

Liver tumors are common and may be unamenable to surgery or ablative treatments. Consequently, other treatments have been devised. To assess the safety and efficacy of transarterial radioembolization (TARE) with Yttrium-90 for hepatocellular carcinoma (HCC), liver-dominant hepatic colorectal cancer metastases (mCRC), and cholangiocarcinoma (CCA), performed according to current recommendations, we conducted a single-center retrospective study in 70 patients treated with TARE (HCC, n = 44; mCRC, n = 20; CCA, n = 6). Safety and toxicity were assessed using the National Cancer Institute Common Terminology Criteria. Treatment response was evaluated every 3 months on imaging studies using Response Evaluation Criteria in Solid Tumors (RECIST) or mRECIST criteria. Overall survival and progression-free survival were estimated using the Kaplan-Meier method. The median delivered dose was 1.6 GBq, with SIR-Spheres® or TheraSphere® microspheres. TARE-related grade 3 adverse events affected 17.1% of patients. Median follow-up was 32.1 months. Median progression-free survival was 5.6 months and median overall time from TARE to death was 16.1 months and was significantly shorter in men. Progression-free survival was significantly longer in women (HR, 0.49; 95%CI, 0.26-0.90; p = 0.031). Risk of death or progression increased with the number of systemic chemotherapy lines. TARE can be safe and effective in patients with intermediate- or advanced-stage HCC, CCA, or mCRC refractory or intolerant to appropriate treatments.

[Effect of 99mTc elution in vivo from red cells on red cell volumes measured using autologous 99mTc-labeled red cells: comparison with 51Cr method]. / Effet de l'élution in vivo du technétium sur les volumes globulaires mesurés à l'aide d'hématies autologues marquées au 99mTc : comparaison avec la technique au 51Cr.

The purpose of this work was to compare the measured red-cell volume (RCV) using sodium pertechnétate [RCV-99mTc] compared to the reference technique using sodium radiochromate [RCV-51Cr] and to assess the influence of technetium-99 elution on the RCV-99mTc value. Ten patients had simultaneous measurements of RCV-99mTc and RCV-51Cr. Elution of Tc-99m from red blood cells was 2.9% and led to an average overestimation of RCV-99mTc of 3.7%. The introduction of individual tracer elution rates in the RCV-99mTc calculation corrects this overestimation.

Combination of breast imaging parameters obtained from 18F-FDG PET and CT scan can improve the prediction of breast-conserving surgery after neoadjuvant chemotherapy in luminal/HER2-negative breast cancer.

INTRODUCTION: The luminal/Human Epidermal growth factor Receptor 2 (HER2) negative subtype of breast cancer has low chemo-sensitivity. When neoadjuvant chemotherapy (NAC) is indicated in this subtype, before a possible breast-conserving surgery (BCS), it is more reasonable to target tumor shrinkage than complete pathological tumor response. We aimed to identify breast and tumor 18Fluoro-deoxy-glucose (18F-FDG) PET-CT scan imaging features for the early prediction of BCS after NAC in luminal/HER2 negative subtypes of breast cancer. MATERIAL AND METHODS: Seventy-seven consecutive women with luminal/HER2-negative breast cancer for whom BCS was initially not feasible and NAC was prescribed, to decrease tumor size before surgery, were included retrospectively. An 18F-FDG PET-CT scan exam was performed before and after the first course of NAC. RESULTS: After NAC, 36% (28/77) of women had a mastectomy and 64% (49/77) underwent BCS. Patients with a mastectomy had lower total breast volume (BVtotal) (p = 0.002), lower decrease in Δmetabolic tumor volume (ΔMTV) (p = 0.03) and lower SUVmax2 (p = 0.05). Using ROC Curve analyses to define the optimal predictive threshold of BVtotal (496 cm3) and ΔMTV (-17.1%), 3 subgroups of women with different odds of BCS after treatment were identified (p = 0.001): low, medium and high probability groups (respectively 29%, 62% and 82%). CONCLUSIONS: For patients with Luminal/HER2 negative breast cancer, the combination of the imaging features of the tumor and the mammary gland, obtained with 18F-FDG PET-CT at baseline and after the first cycle of NAC, may allow the physician to evaluate the probability of BCS.

SUV calculation in breast cancer: which normalization should be applied when using 18F-FDG PET?

BACKGROUND: When using 18F-FDG PET, glucose metabolism quantification is affected by various factors. We aimed to investigate the benefit of different standardized uptake value (SUV) normalizations to improve the accuracy of 18F-FDG uptake to predict breast cancer aggressiveness and response to treatment. METHODS: Two hundred fifty-two women with locally advanced breast cancer treated with neoadjuvant chemotherapy (NAC) were included. Women underwent 18F-FDG PET before and after the first course of NAC. Glucose serum levels, patient heights and weights were recorded at the time of each PET exam. Four different procedures for SUV normalization of the primary tumor were used: by body weight (SUVBW) by blood glucose level (SUVG), by lean body mass (SUL) and then corrected for both lean body mass and blood glucose level (SULG). RESULTS: At baseline, SUL was significantly lower than SUVBW (5.9±4.0 and 9.5±6.5, respectively; P<0.0001), whereas SUVG and SUVBW were not significantly different (9.7±6.4 and 9.5±6.5, respectively; P=0.67). Concerning SUV changes (ΔSUV), the different normalizations methods did not induce significant quantitative differences. The correlation coefficients were high between the four normalizations methods of SUV1, SUV2 and ΔSUVB (R>0.95; P<0.0001). High baseline SUVBW measures were positively correlated with the biological tumor characteristics of aggressiveness and proliferation (P<0.001): ductal carcinoma, high tumor grading, high mitotic activity, negative estrogen receptor status and the TNBC subtype. ΔSUVBW was highly predictive of pCR (AUC=0.76 on ROC curve analysis; P<0.0001). The different SUV normalizations yields identical statistical results and AUC to predict tumor biological aggressiveness and response to therapy. CONCLUSIONS: In the present setting, SUVBW and SUL can be considered as robust measures and be used in future multicenter trials. The additional normalization of SUV by glycemia involves stringent methodologic procedures to avoid biased risk measurements and offers no statistical advantages.

[CA 125 assay in the extension assessment of newly diagnosed breast cancers: why and how?] / Le CA 125 dans le bilan d'extension des cancers du sein nouvellement diagnostiqués : pourquoi et comment ?

CA 125 assay is sometimes combined in practice with the one of CA 15-3 and CEA in the extension assessment of breast cancers. The purpose of this work is to evaluate the contribution of the initial CA 125 as an indicator of distant metastases (DM) or of serous inflammation (SI). This retrospective study concerns a population of 620 patients with breast cancer without metastatic extension (n=325) or metastatic breast cancer (n=295) diagnosed at the Georges-François Leclerc center from 1998 to 2014. Seventy-four patients had SI. We showed that initial CA 125 level is linked to the TNM clinic status, the HER2 status, the nature and the number of metastatic locations, the inflammation of the tumor or serous. The ROC curves and logistic regression analyses show that CA 125 is an independent predictive criterion of DM presence (threshold of 55 kU/L): this is the only positive marker in 7% of patients with DM. At the threshold of 110 kU/L, the CA 125 is the only predictive biologic factor for SI. In conclusion, these data present the independent predictive value of CA 125 on the presence of DM or SI on condition of usinga specific threshold for each of these uses.

FDG PET/CT for prognostic stratification of patients with metastatic breast cancer treated with first line systemic therapy: Comparison of EORTC criteria and PERCIST.

AIM: Evaluate response and predict prognosis of patients with newly diagnosed metastatic breast cancer treated with first line systemic therapy using European Organization for Research and Treatment of Cancer (EORTC) criteria and PET Response Criteria in solid Tumours (PERCIST). METHODS: From December 2006 to August 2013, 57 women with newly diagnosed metastatic breast cancer were retrospectively evaluated. FDG-PET/CT was performed within one month before treatment and repeated after at least 3 cycles of treatment. Metabolic response evaluation was evaluated by two readers according to both EORTC criteria and PERCIST, classifying the patients into 4 response groups: complete metabolic response (CMR), partial metabolic response (PMR), stable metabolic disease (SMD), and progressive metabolic disease (PMD). RESULTS: With EORTC criteria, 22 patients had CMR, 17 PMR, 6 SMD and 12 PMD. With PERCIST, 20 patients had CMR, 15 PMR, 10 SMD and 12 PMD. There was agreement between EORTC and PERCIST in 84% of the patients. By log-rank analysis, metabolic response evaluated with both EORTC criteria and PERCIST was able to predict overall survival (p = 0.028 and 0.002 respectively). CMR patient group had longer median OS than patients in the combined PMR+SMD+PMD group (60 vs 26 months both with EORTC and PERCIST; p = 0.009 and 0.006 respectively). By multivariate analysis, CMR either with EORTC or PERCIST remained an independent predictor of survival. CONCLUSION: Metabolic response evaluation with EORTC criteria and PERCIST gave similar prognostic stratification for metastatic breast cancer treated with a first line of systemic therapy.

Induction of peroxisomal changes in oligodendrocytes treated with 7-ketocholesterol: Attenuation by α-tocopherol.

The involvement of organelles in cell death is well established especially for endoplasmic reticulum, lysosomes and mitochondria. However, the role of the peroxisome is not well known, though peroxisomal dysfunction favors a rupture of redox equilibrium. To study the role of peroxisomes in cell death, 158 N murine oligodendrocytes were treated with 7-ketocholesterol (7 KC: 25-50 µM, 24 h). The highest concentration is known to induce oxiapoptophagy (OXIdative stress + APOPTOsis + autoPHAGY), whereas the lowest concentration does not induce cell death. In those conditions (with 7 KC: 50 µM) morphological, topographical and functional peroxisome alterations associated with modifications of the cytoplasmic distribution of mitochondria, with mitochondrial dysfunction (loss of transmembrane mitochondrial potential, decreased level of cardiolipins) and oxidative stress were observed: presence of peroxisomes with abnormal sizes and shapes similar to those observed in Zellweger fibroblasts, lower cellular level of ABCD3, used as a marker of peroxisomal mass, measured by flow cytometry, lower mRNA and protein levels (measured by RT-qPCR and western blotting) of ABCD1 and ABCD3 (two ATP-dependent peroxisomal transporters), and of ACOX1 and MFP2 enzymes, and lower mRNA level of DHAPAT, involved in peroxisomal ß-oxidation and plasmalogen synthesis, respectively, and increased levels of very long chain fatty acids (VLCFA: C24:0, C24:1, C26:0 and C26:1, quantified by gas chromatography coupled with mass spectrometry) metabolized by peroxisomal ß-oxidation. In the presence of 7 KC (25 µM), slight mitochondrial dysfunction and oxidative stress were found, and no induction of apoptosis was detected; however, modifications of the cytoplasmic distribution of mitochondria and clusters of mitochondria were detected. The peroxisomal alterations observed with 7 KC (25 µM) were similar to those with 7 KC (50 µM). In addition, data obtained by transmission electron microcopy and immunofluorescence microscopy by dual staining with antibodies raised against p62, involved in autophagy, and ABCD3, support that 7 KC (25-50 µM) induces pexophagy. 7 KC (25-50 µM)-induced side effects were attenuated by α-tocopherol but not by α-tocotrienol, whereas the anti-oxidant properties of these molecules determined with the FRAP assay were in the same range. These data provide evidences that 7 KC, at concentrations inducing or not cell death, triggers morphological, topographical and functional peroxisomal alterations associated with minor or major mitochondrial changes.

Clinical value of CA 15-3 for detection of distant metastases in newly diagnosed breast cancer.

The aim of the study is to investigate the clinical value of CA 15-3 for detection of distant metastases (DM) in newly diagnosed breast cancer. This retrospective study focuses on a population of 1,007 patients with locally advanced breast cancer (n=561) or metastatic breast cancer (n=446) diagnosed at the CGFL (Centre Georges Francois Leclerc) from March 1998 to October 2013. These patients underwent a measurement of CA 15-3 and an assessment of extension before any treatment. The cut-off value of CA 15-3 was determined and verified on two independents subpopulations determined in drawing lots. The ROC curve shows an AUC of 0.85 (p<0.0001). At the threshold of 50 kU/L, CA 15-3 before treatment has a predictive value on the existence of DM independently of the other prognostics factors. This predictive value has been found in every molecular subtype (AUC≥ 0.70; p≤ 0,085). The rate of false negative is of 38% and depends on the number and the type of the metastatic localization. Among the 28 patients without DM and a CA 15-3> 50 kU/L, 13 have developed DM and 11 died of cancer. In conclusion, these facts confirm the independently predictive value of CA 15-3 before treatment on the existence of DM and the complementarity of the marker with the assessment of extension by imagery.

Clinical value of CEA for detection of distant metastases in newly diagnosed breast cancer: comparison with CA 15-3.

The aim of the study is to investigate the clinical value of CEA (carcinoembryonic antigen) for detection of distant metastases (DM) in newly diagnosed breast cancer. This retrospective study focuses on a population of 929 patients with locally advanced breast cancer (n=521) or metastatic breast cancer (n=408) diagnosed at the CGFL (Centre Georges Francois Leclerc) from 1998 to 2014. These patients underwent a measurement of CA 15-3, a measurement of CEA and an assessment of extension before any treatment. The initial concentrations of CEA are correlated with conventional prognostic factors. The cut-off value of CEA was determined and verified on two independents subpopulations determined in drawing lots. The ROC curve shows an AUC of 0.82 (p<0.0001). At the threshold of 6.7 µg/L, CEA before treatment has a predictive value on the existence of DM independently of the CA 15-3 and other prognostic factors. The combination of CEA and CA 15-3 increases significantly the predictive value of CA 15-3 on the whole population (sensitivity increased by 9%) and on tumors expressing hormonal receptors. Concerning the only CEA the rate of false negative is of 52% and depends on the number and the type of the metastatic localization. Among the 28 patients without DM and a CEA > 6.7 µg/L, 15 have developed DM and 2 a new cancer. Thirteen will die of cancer. In conclusion, these facts confirm the independently predictive value of CEA before treatment on the existence of DM and its complementarity with CA 15-3 during the assessment of extension by imagery.

Identification and validation of a factor of commutability between platelet counts performed on EDTA and citrate.

The anticoagulant mostly employed for platelet count is EDTA. The Francophone Group of Cellular Hematology recommends checking of blood smear stained with May-Grünwald Giemsa any thrombocytopenia less than 100 G/L without medical history or whether an alarm is generated by the cell counter. The pseudo-thrombocytopenia (PTP) with EDTA is the best known artifact in platelet count. A sample of blood on citrated tube is necessary to get rid of the interference. The objective of this study was to compare the platelet counts obtained on EDTA (numEDTA) and citrate (numCTAD) tubes and to define, then validate a factor of conversion between both methods. The prevalence of PTP EDTA is 0.26%. The PTP was transient in 80% of the patients. The numEDTA and numCTAD+10% (numCTAD increased by 10% to take dilution into account) are correlated but are not equivalent. The numCTAD+10% underestimate numEDTA significantly. The systematic bias is removed if we increase by 17% numCTAD. The factor of correction is stable over a period of 3 hours.

Attenuation of 7-ketocholesterol-induced overproduction of reactive oxygen species, apoptosis, and autophagy by dimethyl fumarate on 158N murine oligodendrocytes.

Mitochondrial dysfunctions and oxidative stress are involved in several non demyelinating or demyelinating neurodegenerative diseases. Some of them, including multiple sclerosis (MS), are associated with lipid peroxidation processes leading to increased levels of 7-ketocholesterol (7KC). So, the eventual protective effect of dimethylfumarate (DMF), which is used for the treatment of MS, was evaluated on 7KC-treated oligodendrocytes, which are myelin synthesizing cells. To this end, murine oligodendrocytes 158N were exposed to 7KC (25, 50µM) for 24h without or with DMF (1, 25, 50µM). The biological activities of DMF associated or not with 7KC were evaluated by phase contrast microscopy, crystal violet and MTT tests. The impact on transmembrane mitochondrial potential (ΔYm), O2- and H2O2 production, apoptosis and autophagy was measured by microscopical and flow cytometric methods by staining with DiOC6(3), dihydroethidine and dihydrorhodamine 123, Hoechst 33342, and by Western blotting with the use of specific antibodies raised against uncleaved and cleaved caspase-3 and PARP, and LC3-I/II. DMF attenuates the different effects of 7KC, namely: cell growth inhibition and/or loss of cell adhesion, decrease of ΔΨm, O2- and H2O2 overproduction, PARP and caspase-3 cleavage, nuclear condensation and fragmentation, and activation of LC3-I into LC3-II. The ability of DMF to attenuate 7KC-induced reactive oxygen species overproduction, apoptosis, and autophagy on oligodendrocytes reinforces the interest for this molecule for the treatment of MS or other demyelinating diseases.

7-Ketocholesterol is increased in the plasma of X-ALD patients and induces peroxisomal modifications in microglial cells: Potential roles of 7-ketocholesterol in the pathophysiology of X-ALD.

X-linked adrenoleukodystrophy (X-ALD) is a genetic disorder induced by a mutation in the ABCD1 gene, which causes the accumulation of very long-chain fatty acids in tissue and plasma. Oxidative stress may be a hallmark of X-ALD. In the plasma of X-ALD patients with different forms of the disease, characterized by high levels of C24:0 and C26:0, we observed the presence of oxidative stress revealed by decreased levels of GSH, α-tocopherol, and docosahexaenoic acid (DHA). We showed that oxidative stress caused the oxidation of cholesterol and linoleic acid, leading to the formation of cholesterol oxide derivatives oxidized at C7 (7-ketocholesterol (7KC), 7ß-hydroxycholesterol (7ß-OHC), and 7α-hydroxycholesrol (7α-OHC)) and of 9- and 13-hydroxyoctadecadienoic acids (9-HODE, 13-HODE), respectively. High levels of 7KC, 7ß-OHC, 7α-OHC, 9-HODE and 13-HODE were found. As 7KC induces oxidative stress, inflammation and cell death, which could play key roles in the development of X-ALD, the impact of 7KC on the peroxisomal status was determined in microglial BV-2 cells. Indeed, environmental stress factors such as 7KC could exacerbate peroxisomal dysfunctions in microglial cells and thus determine the progression of the disease. 7KC induces oxiapoptophagy in BV-2 cells: overproduction of H2O2 and O2-, presence of cleaved caspase-3 and PARP, nuclear condensation and/or fragmentation; elevated [LC3-II/LC3-I] ratio, increased p62 levels. 7KC also induces several peroxisomal modifications: decreased Abcd1, Abcd2, Abcd3, Acox1 and/or Mfp2 mRNA and protein levels, increased catalase activity and decreased Acox1-activity. However, the Pex14 level was unchanged. It is suggested that high levels of 7KC in X-ALD patients could foster generalized peroxisomal dysfunction in microglial cells, which could in turn intensify brain damage.

[Validation steps for the detection of L858R mutation in EGFR gene by real time quantitative PCR]. / Validation de méthode de la recherche de la mutation L858R par PCR en temps réel utilisant les sondes fluorescentes Taqman® dans les cancers bronchiques non à petites cellules.

Since January 16(th) 2010, the French legislation requires that the medical laboratories must be accredited according to ISO 15189 standards. This concerned all the biological medical technics, including molecular biology technics. In this work, we described the validation steps by real time quantitative PCR of L858R mutation in EGFR gene, frequently detected in non-small lung cancers (NSCLC). Epidermal growth factor - tyrosine kinase inhibitors (EGFR-TKIs) are authorized in Europe for the treatment of metastatic NSCLC after failure of, at least one, prior chemotherapy. Thus, in view of accreditation of this analysis, we have used the recommendation of the COFRAC (Comité français d'accréditation) and INCa (Institut national du cancer). Several parameters have been tested, such as the primers, the limit of detection, and the sensitivity and specificity of the method. In addition, a risk study has been evaluated. Although long and fastidious, the method of validation is required to perform analysis in optimal conditions to guaranty optimal results for the patients.

18F-FDG PET-Derived Tumor Blood Flow Changes After 1 Cycle of Neoadjuvant Chemotherapy Predicts Outcome in Triple-Negative Breast Cancer.

Previous studies have suggested that early changes in blood flow (BF) in response to neoadjuvant chemotherapy and evaluated with 15O-water are a surrogate biomarker of outcome in women with breast cancer. This study investigates, in the triple-negative breast cancer subtype, the prognostic relevance of tumor BF changes (ΔBF) in response to chemotherapy, assessed using a short dynamic 18F-FDG PET acquisition. METHODS: Forty-six consecutive women with triple-negative breast cancer and an indication for neoadjuvant chemotherapy were prospectively included. Women benefited from a baseline 18F-FDG PET examination with a 2-min chest-centered dynamic acquisition, started at the time of 18F-FDG injection. Breast tumor perfusion was calculated from this short dynamic image using a first-pass model. This dynamic PET acquisition was repeated after the first cycle of chemotherapy to measure early ΔBF. Delayed static PET acquisitions were also performed (90 min after 18F-FDG injection) to measure changes in tumor glucose metabolism (ΔSUVmax). The association between tumor BF, clinicopathologic characteristics, and patients' overall survival (OS) was evaluated. RESULTS: Median baseline tumor BF was 21 mL/min/100 g (range, 6-46 mL/min/100 g) and did not significantly differ according to tumor size, Scarf-Bloom-Richardson grade, or Ki-67 expression. Median tumor ∆BF was -30%, with highly scattered values (range, -93% to +118%). A weak correlation was observed between ΔBF and ∆SUVmax (r = +0.40, P = 0.01). The median follow-up was 30 mo (range, 6-73 mo). Eight women developed recurrent disease, 7 of whom died. Low OS was associated with menopausal history (P = 0.03), persistent or increased tumor vascularization on the interim PET (ΔBF cutoff = -30%; P = 0.03), non-breast-conserving surgery (P = 0.04), and the absence of a pathologic complete response (pCR) (P = 0.01). ΔBF and pCR provided incremental prognostic stratification: 3-y OS was 100% in pCR women, 87% in no-pCR women but achieving an early tumor BF response, and only 48% in no-pCR/no-BF-response women (ΔBF cutoff = -30%, P < 0.001). CONCLUSION: This study suggests the clinical usefulness of an early user- and patient-friendly 2-min dynamic acquisition to monitor breast tumor ΔBF to neoadjuvant chemotherapy using 18F-FDG PET/CT. Monitoring tumor perfusion and angiogenesis response to treatment seems to be a promising target for PET tracers.