Hormonal Receptor Immunochemistry Heterogeneity and 18F-FDG Metabolic Heterogeneity: Preliminary Results of Their Relationship and Prognostic Value in Luminal Non-Metastatic Breast Cancers

Introduction

We aimed to investigate whether ¹⁸F-FDG PET metabolic heterogeneity reflects the heterogeneity of estrogen receptor (ER) and progesterone receptor (PR) expressions within luminal non-metastatic breast tumors and if it could help in identifying patients with worst event-free survival (EFS).

Materials and methods

On 38 PET high-resolution breast bed positions, a single physician drew volumes of interest encompassing the breast tumors to extract SUV_max, histogram parameters and textural features. High-resolution immunochemistry (IHC) scans were analyzed to extract Haralick parameters and descriptors of the distribution shape. Correlation between IHC and PET parameters were explored using Spearman tests. Variables of interest to predict the EFS status at 8 years (EFS-8y) were sought by means of a random forest classification. EFS-8y analyses were then performed using univariable Kaplan-Meier analyses and Cox regression analysis. When appropriate, Mann-Whitney tests and Spearman correlations were used to explore the relationship between clinical data and tumoral PET heterogeneity variables.

Results

For ER expression, correlations were mainly observed with ¹⁸F-FDG histogram parameters, whereas for PR expression correlations were mainly observed with gray-level co-occurrence matrix (GLCM) parameters. The strongest correlations were observed between skewness__ER and uniformity__HISTO (ρ = −0.386, p = 0.017) and correlation__PR and entropy__GLCM (ρ = 0.540, p = 0.001), respectively. The median follow-up was 6.5 years and the 8y-EFS was 71.0%. Random forest classification found age, clinical stage, SUV_max, skewness__ER, kurtosis__ER, entropy__HISTO, and uniformity__HISTO to be variables of importance to predict the 8y-EFS. Univariable Kaplan-Meier survival analyses showed that skewness__ER was a predictor of 8y-EFS (66.7 ± 27.2 versus 19.1 ± 15.2, p = 0.018 with a cut-off value set to 0.163) whereas other IHC and PET parameters were not. On multivariable analysis including age, clinical stage and skewness__ER, none of the parameters were independent predictors. Indeed, skewness__ER was significantly higher in youngest patients (ρ = −0.351, p = 0.031) and in clinical stage III tumors (p = 0.023).

Conclusion

A heterogeneous distribution of ER within the tumor in IHC appeared as an EFS-8y prognosticator in luminal non-metastatic breast cancers. Interestingly, it appeared to be correlated with PET histogram parameters which could therefore become potential non-invasive prognosticator tools, provided these results are confirmed by further larger and prospective studies.

Characterization of HIV risks in a Brazilian sickle cell disease population

BACKGROUND

A low prevalence of HIV in sickle cell disease (SCD) patients has been reported in the literature though mechanisms for this are not understood.

METHODS

HIV risk behaviors were compared between SCD cases and non-SCD controls using a self-administered audio computer-assisted self-interview. SCD cases were recruited from a multi-center SCD cohort established in Brazil; controls were recruited from SCD social contacts. Categorical variables were analyzed using Chi-Square or Fisher exact test. Continuous variables were compared using the Mann-Whitney U test.

RESULTS

There were 152 SCD cases and 154 age/location matched controls enrolled at three participating Brazilian centers during 2016-17. No significant differences in number of sexual partners (lifetime or previous 12 months), male-to-male sex partners or intravenous drug use were observed. Cases received more transfusions, surgeries, and acupuncture treatment.

CONCLUSIONS

Besides the risk of transfusion-transmitted HIV, which is now exceedingly rare, SCD and non-SCD participants demonstrated similar HIV risk behaviors. Causes other than risk behaviors such as factors inherent to SCD pathophysiology may explain the reported low prevalence of HIV in SCD.

How fast can we scan patients with modern (digital) PET/CT systems?

PURPOSE

To seek for the minimal duration per bed position with a digital PET system without compromising image quality and lesion detection in patients requiring fast ¹⁸F-FDG PET imaging.

MATERIALS AND METHODS

19 cancer patients experiencing pain or dyspnea and 9 pediatric patients were scanned on a Vereos system. List mode data were reconstructed with decreasing time frame down to 10 s per bed position. Noise was evaluated in the liver, blood pool and muscle, and using target-to-background ratios. Five PET readers recorded image quality, number of clinically relevant foci and of involved anatomical sites in reconstructions ranging from 60 to 10 s per bed position, compared to the standard 90 s reconstruction.

RESULTS

The following reconstructions, which harboured a noise not significantly higher than that of the standard reconstruction, were selected for clinical evaluation: 1iterations/10 subsets/20_sec (1i10 s20_sec), 1i10 s30_sec, and 2i10 sPSF60_sec. Only the 60 s per bed acquisition displayed similar target-to-background ratios compared to the standard reconstruction, but mean ratios were still higher than 2.0 for the 30 s reconstruction. Inter-rater agreement for the number of involved anatomical sites and detected lesion was good or almost perfect (Kappa: 0.64-0.91) for all acquisitions. In particular, kappa for the 30 s per bed acquisition was 0.78 and 0.91 for lesion and anatomical sites number, respectively. Intra-rater agreement was also excellent for the 30 s reconstruction (kappa = 0.72). Median estimated total PET acquisition time for the 1i10 s30_sec, and the standard reconstruction were 4 and 12 min, respectively.

CONCLUSIONS

Fast imaging is feasible with state-of-the-art PET systems. Acquisitions of 30 s per bed position are feasible with the Vereos system, requiring optimization of reconstruction parameters.

Implications of reconstruction protocol for histo-biological characterisation of breast cancers using FDG-PET radiomics

BACKGROUND

The aim of this study is to determine if the choice of the ¹⁸F-FDG-PET protocol, especially matrix size and reconstruction algorithm, is of importance to discriminate between immunohistochemical subtypes (luminal versus non-luminal) in breast cancer with textural features (TFs).

PROCEDURES

Forty-seven patients referred for breast cancer staging in the framework of a prospective study were reviewed as part of an ancillary study. In addition to standard PET imaging (PSF_WholeBody), a high-resolution breast acquisition was performed and reconstructed with OSEM and PSF (OSEM_breast/PSF_breast). PET standard metrics and TFs were extracted. For each reconstruction protocol, a prediction model for tumour classification was built using a random forests method. Spearman coefficients were used to seek correlation between PET metrics.

RESULTS

PSF_WholeBody showed lower numbers of voxels within VOIs than OSEM_breast and PSF_breast with median (interquartile range) equal to 130 (43-271), 316 (167-1042), 367 (107-1221), respectively (p < 0.0001). Therefore, using LifeX software, 28 (59%), 46 (98%) and 42 (89%) patients were exploitable with PSF_WholeBody, OSEM_breast and PSF_breast, respectively. On matched comparisons, PSF_breast reconstruction presented better abilities than PSF_wholeBody and OSEM_breast for the classification of luminal versus non-luminal breast tumours with an accuracy reaching 85.7% as compared to 67.8% for PSF_wholeBody and 73.8% for OSEM_breast. PSF_breast accuracy, sensitivity, specificity, PPV and NPV were equal to 85.7%, 94.3%, 42.9%, 89.2%, 60.0%, respectively. Coarseness and ZLNU were found to be main variables of importance, appearing in all three prediction models. Coarseness was correlated with SUV_max on PSF_wholeBody images (ρ = - 0.526, p = 0.005), whereas it was not on OSEM_breast (ρ = - 0.183, p = 0.244) and PSF_breast (ρ = - 0.244, p = 0.119) images. Moreover, the range of its values was higher on PSF_breast images as compared to OSEM_breast, especially in small lesions (MTV < 3 ml).

CONCLUSIONS

High-resolution breast PET acquisitions, applying both small-voxel matrix and PSF modelling, appeared to improve the characterisation of breast tumours.

Assessment of alteration in liver 18F-FDG uptake due to steatosis in lymphoma patients and its impact on the Deauville score

AIM

Our aim was (1) to evaluate the prevalence of steatosis in lymphoma patients and its evolution during treatment; (2) to evaluate the impact of hepatic steatosis on ¹⁸F-FDG liver uptake; and (3) to study how hepatic steatosis affects the Deauville score (DS) for discriminating between responders and non-responders.

METHODS

Over a 1-year period, 358 PET scans from 227 patients [122 diffuse large B cell lymphoma (DLBCL), 57 Hodgkin lymphoma (HL) and 48 Follicular lymphoma (FL)] referred for baseline (n = 143), interim (n = 79) and end-of-treatment (EoT, n = 136) PET scans were reviewed. Steatosis was diagnosed on the unenhanced CT part of PET/CT examinations using a cut-off value of 42 Hounsfield units (HU). EARL-compliant SUL_max were recorded on the liver and the tumour target lesion. DS were then computed.

RESULTS

Prevalence of steatosis at baseline, interim and EoT PET was 15/143 (10.5%), 6/79 (7.6%) and 16/136 (11.8%), respectively (p = 0.62).Ten out of 27 steatotic patients (37.0%) displayed a steatotic liver on all examinations. Six patients (22.2%) had a disappearance of hepatic steatosis during their time-course of treatment. Only one patient developed steatosis during his course of treatment. Liver SUL_max values were significantly lower in the steatosis versus non-steatotic groups of patients for interim (1.66 ± 0.36 versus 2.15 ± 0.27) and EoT (1.67 ± 0.29 versus 2.17 ± 0.30) PET. CT density was found to be an independent factor that correlated with liver SUL_max, while BMI, blood glucose level and the type of chemotherapy regimen were not. Using a method based on this correlation to correct liver SUL_max, all DS4 steatotic patients on interim (n = 1) and EoT (n = 2) PET moved to DS3.

CONCLUSIONS

Steatosis is actually a theoretical but not practical issue in most patients but should be recognised and corrected in appropriate cases, namely, for those patients scored DS4 with a percentage difference between the target lesion and the liver background lower than 30%.

Determining the health-related quality of life in individuals with haemophilia in developing economies: results from the Brazilian population

INTRODUCTION

Several studies show the negative impact of haemophilia in health-related quality of life (HRQOL). This issue is not well explored in developing countries.

OBJECTIVES

This cross-sectional study aimed to evaluate the HRQOL and its associated factors in patients with haemophilia A/B in Brazil. Data were collected by questionnaire and in medical records, including a Portuguese version of Haem-A-Qol.

RESULTS

Brazilian patients were invited to the study and 175 participants (147 haemophilics A and 28 haemophilics B) were included. The total score of the Haem-A-QoL had a median of 36.96 (range of 0-100), with worse performance in 'sport and leisure' and best on 'relationships' fields. HRQOL was worst among the older participants, the less educated, non-white, non-working, who were hospitalized in the last year, who did not have a single medical consultation and among those with the highest number of affected joints. Moreover, patients with hepatitis B had a significantly worse HRQOL in the domain 'sports and leisure', also observed in married patients. Otherwise, married individuals reported better HRQOL on 'dealing with the disease' domain. Patients with haemophilia B reported worse HRQOL in the domain 'self-perception'.

CONCLUSION

The results obtained could be helpful in guidance of haemophilia treatment which is determinant to improve HRQoL of the most vulnerable groups of patients. This work also reinforced the relevance of joint bleeds in all aspects of HRQoL in haemophilic patients. The use of prophylactic factor concentrates and multidisciplinary treatments could contribute to improve the quality of life in haemophilia.

Generating harmonized SUV within the EANM EARL accreditation program: software approach versus EARL-compliant reconstruction

BACKGROUND

Evolutions in hardware and software PET technology, such as point spread function (PSF) reconstruction, have been shown to improve diagnostic performance, but can also lead to important device-dependent and reconstruction-dependent variations in standardized uptake values (SUVs). This may preclude the multicentre use of SUVs as a prognostic or diagnostic tool or as a biomarker of the early response to antineoplastic treatments. This study compared two SUV harmonization strategies using a newer reconstruction algorithm that improves lesion detection while maintaining comparability with older systems: (1) the use of a second reconstruction compliant with harmonization standards and (2) the use of a proprietary software tool (EQ.PET).

METHODS

PET data from 50 consecutive non-small cell lung cancer patients were reconstructed with PSF reconstruction for optimal tumor detection and an ordered subset expectation maximization (OSEM3D) reconstruction to mimic a former generation PET. An additional PSF reconstruction was performed with a 7 mm Gaussian filter (PSF₇, first method), and, post-reconstruction, the EQ filter (same Gaussian filter) was applied to the PSF data (PSF_EQ, second method) for harmonization purposes. The 7 mm kernel filter was chosen to comply with the European Association of Nuclear Medicine (EANM) standards. SUVs for all reconstructions were compared with regression analyses and/or Bland-Altman plots.

RESULTS

Overall, 171 lesions were analyzed: 55 lung lesions (32.2%), 87 lymph nodes (50.9%), and 29 metastases (16.9%). In these lesions, the mean PSF₇/OSEM3D ratios for SUV_max and SUV_peak were 1.02 (95% CI: 0.93-1.11) and 1.04 (95% CI: 0.95-1.14), respectively. The mean PSF_EQ/OSEM3D ratios for SUV_max and SUV_peak were 1.01 (95% CI: 0.91-1.11) and 1.04 (95% CI: 0.94-1.14), respectively. When comparing PSF₇ and PSF_EQ, Bland-Altman analysis showed that the mean PSF₇/PSF_EQ ratios for SUV_max and SUV_peak were 1.01 (95% CI: 0.96-1.06) and 1.01 (95% CI: 0.97-1.04), respectively.

CONCLUSION

The issue of reconstruction dependency in SUV values that hampers the comparison of data between different PET systems can be overcome using two reconstructions for harmonized quantification and optimal diagnosis or using the EQ.PET technology. Both technologies produce similar results, EQ.PET sparing reconstruction and interpretation time. Other manufacturers are encouraged to either emulate this solution or to produce a vendor-neutral approach.

[Outcome evaluation of a health promotion among the elderly]

The programme "active health promotion in old age" focuses on responsible self determination in old age (empowerment) and places special emphasis on physical activity and nutrition. The intervention, successfully conducted in an urban setting (Hamburg), was tested in a rural area (Kinzigtal, Baden-Wuerttemberg). In this paper we present the results of the outcome evaluation. The intervention group consisted of older people, without care need and without cognitive impairment who lived in their own home (N=468). For the evaluation of the results a pre-post comparison was conducted (2 measuring points within an interval of 12 months). 4 out of 5 participants reported changes in their behaviour after the intervention. However, the pre-post comparison shows significant changes only for nutrition behaviour, but not of physical activity. Health related quality of life (SF-36) did not change after 12 months. These findings indicate that health promotion in old age may lead to changes in nutrition behaviour.

[Active health promotion among the aged in a rural region. Participants, acceptance, and implementation]

The program "active health promotion in old age" focuses on persons aged 60 years and older who are not in need of care and are living independently without cognitive impairment. The objective of the intervention is to improve physical activity, healthy nutrition, and the integration of older people into network structures. The intervention was successfully conducted in an urban setting and has now been transferred to a rural area in southwestern Germany (Baden-Wuerttemberg). It was offered to statutory health insured people of Baden-Wuerttemberg within an integrated care program and was free of charge. This article reports the results of the process evaluation. For data collection, participants were interviewed using a standardized questionnaire. Semistructured interviews were conducted with the intervention team and involved general practitioners. In addition, secondary data were used to analyze selection bias between participants and nonparticipants. Although the rural area has a major impact on recruitment, access, and factors of implementation, results demonstrate that the intervention is highly accepted by participants. Moreover, structural conditions (e.g., fitness clubs, exercise classes) are essential for a successful transfer.

[Experience with the linkage of primary and secondary claims data in an intervention trial]

The data linkage of health-related primary and secondary data provides new opportunities for health services research. The advantages of both data sources can be used synergistically, in this way their disadvantages can be overcome. In the context of the evaluation of a health intervention - the integrated health services project ('Gesundes Kinzigtal') - the conditions and requirements for an individualised data linkage of primary data (survey) and claims data of a statutory health insurance are described in this paper. The integration of secondary data permits us not only to assess the intervention concerning physical activity, nutrition and social participation of elderly people ('AGil') but, above all, also to measure and analyse the program effects on the utilisation of health care services. Recommendations regarding the data linkage of primary and secondary data in health services research are derived from the results and experiences of the AGil study. Suggestions are made concerning the suitable pseudonymisation algorithm for primary and secondary data, the matching method, approaches to reduce mismatching and their validation, as well as the legal basis for such a data linkage. Overall, an individualised data linkage of primary and secondary data does not pose any technical problems. Nevertheless a couple of data protection rules have to be followed; the data linkage offers a high knowledge insight to many health and epidemiological research questions and might be the new gold standard for health services research.

Onconase, an anti-tumor ribonuclease suppresses intracellular oxidative stress

Onconase (ONC), an antitumor ribonuclease from oocytes of a frog Rana pipiens, capable of inducing apoptosis in many cell lines is synergistic with several other anticancer drugs. Since cytotoxic effects of numerous drugs are modulated by reactive oxygen intermediates (ROI), we have studied effects of ONC on the intracellular level of oxidants in several normal cell types as well as tumor cell lines. It is demonstrated for the first time that ONC substantially decreases the content of ROI in all cell lines studied. This effect depends on the ribonucleolytic activity of the enzyme and is due to both, decreased rate of ROI generation and accelerated rate of their degradation. Onconase decreases the mitochondrial transmembrane potential and consequently, generation of ATP. Simultaneously the enzyme decreases the expression of an antiapoptotic protein Bcl-2, and upregulates the proapoptotic Bax protein. These finding are consistent with the enzyme propensity to induce apoptosis. The observed antioxidant activity of ONC may be an important element of its cytotoxicity towards cancer cells. The enzyme seems to exert its biological activities by interfering with the redox system of cellular regulation.

Malignancy: A New Approach to the Analysis of Apoptosis in the Leukemic Subpopulation by Flow Cytometry Using a CD45 Gating Strategy

Bone marrow and peripheral blood are heterogeneous tissues containing cells of different hematopoietic lineages. It is possible to detect leukemic cells by flow cytometry using a gating strategy, which combines CD45 expression on the cell surface with right angle light scatter (SS). This approach was applied to 15 cases of AML. Myeloblasts had the lowest CD45 fluorescence intensity of any of the cells in the myeloid series and also had the lowest SS, approximately equivalent to monocytes, but greater than lymphoblasts and lymphocytes. Using this gating strategy in each sample we could identify up to 5 separate cell compartments. Our results showed good correlation between the flow differential and the manual differential cell count. However in some cases, especially when a sample became hypocellular, the flow differential was more sensitive in identifying leukemic blasts. Total apoptosis (i.e. apoptosis in all cell populations combined) varied during the treatment between 0-34%. In the blood, the highest percentage of total apoptotic cells usually occurred between day 3-5 of treatment. The percentage of apoptotic cells varied depending on the cell type on a percentage basis. The leukemic population was lesslikely to undergo apoptosis compared to the lymphocytes, monocytes and more mature myeloid cells. In normal cells, apoptosis occurred mostly in G(1) and S phases of the cell cycle. Apoptosis among CD45-blasts usually varied between 0-5%. Myeloblasts also had a tendency to undergo apoptosis in G(1) and S phases of the cell cycle. The CD45-blast apoptotic peak in the blood occurred between day 5-7 of treatment. Analysis of drug-induced apoptosis in bone marrow seems to provide more information than such measurements in peripheral blood.

High affinity binding of fluorescein isothiocyanate to eosinophils detected by laser scanning cytometry: a potential source of error in analysis of blood samples utilizing fluorescein-conjugated reagents in flow cytometry

BACKGROUND

In samples of peripheral blood cells processed using the commercial kits for detection of apoptosis based on DNA strand break labeling, a subpopulation of cells characterized by high green fluorescence, similar in intensity to that of apoptotic cells but more uniform, was consistently observed by flow cytometry. The labeled cells had no other features of apoptosis. The labeling was observed regardless of the fixative used and was evident in control samples lacking terminal deoxynucleotidyltransferase. Common to all the kits that generated this labeling pattern was the presence of fluorescein (f) conjugated reagents, f-dUTP, f-avidin, or f-antibody.

METHODS

Laser scanning cytometry was used to identify the labeled cells and study the mechanism of labeling. Because it was suspected that the traces of unconjugated f-isothiocyanate (FITC) that may contaminate the reagents were responsible for the labeling, FITC binding affinity to white blood cells was studied. Gel electrophoresis was used to detect the presence of unconjugated FITC in the reagents.

RESULTS

After staining with Giemsa, the strongly fluorescent objects were identified as eosinophils with normal morphology and no evidence of apoptosis. The fluorescence was localized exclusively within the cytoplasmic granules. Labeling of eosinophils was observed at 2 nM concentration of FITC, which was over three orders of magnitude lower than that needed to label neutrophils, monocytes, or lymphocytes. Gel electrophoresis of the f-conjugated reagents revealed only minor contamination with FITC.

CONCLUSIONS

(1) Trace amounts of unconjugated FITC contaminating the reagents are adequate to strongly label eosinophils thereby introducing experimental bias in analysis of apoptosis and in other studies on blood cells utilizing f-labeled antibodies, e.g., in detecting cytokines. (2) FITC at concentration 2-500 nM can be used as a marker of eosinophiles; (3) Because of high affinity to FITC, eosinophiles (or the protein from these cells) may serve as a means of removing traces of unconjugated FITC from the reagents during their manufacture or prior to use.