Whole-body tumour burden on [18F]DCFPyL PET/CT in biochemical recurrence of prostate cancer: association with tumour biology and PSA kinetics.

PURPOSE: The objective was to assess the association between molecular imaging (mi) variables on [18F]DCFPyL-PET/CT with clinical and disease characteristics and prostate specific antigen (PSA) related variables in patients with biochemical recurrence of prostate cancer (BRPC). MATERIAL AND METHODS: We analysed patients with BRPC after radical treatment. We obtained clinical and PSA variables: International Society of Urology Pathology (ISUP) grade group, European Association of Urology (EAU) risk classification, PSA (PSA≤1ng/ml, 12), PSA doubling time (PSAdt) and PSA velocity (PSAvel). All PET/CT scans were reviewed with the assistance of automated Prostate Molecular Imaging Standardized Evaluation (aPROMISE) software and lesions' segmentation in positive scans was performed using this platform. Standardized uptake value (SUV) derived variables; tumour burden variables [whole-body tumour volume (wbTV), whole-body tumour lesion activity (wbTLA) and whole-body mi PSMA (wbPSMA)] and miTNM staging were obtained. Cut-off of PSA and kinetics able to predict PET/CT results were obtained. Associations between disease and mi variables were analysed using ANOVA, Kruskal-Wallis and Spearman's correlation tests. Multivariate analysis was also performed. RESULTS: Two hundred and seventy-five patients were studied. [18F]DCFPyL-PET/CT were positive in 165/275 patients. In multivariate analysis, moment of biochemical recurrence, ISUP group, PSA level and PSAvel showed significant association with the detection rate. miTNM showed significant association with PSA level (p<0.001) and kinetics (p<0.001), being higher in patients with metastatic disease. Both PSA and PSAvel showed moderate correlation with wbTV, wbTLA and wbPSMA (p<0.001). A weak correlation with SUVs was found. Mean wbTV, wbTLA and wbPSMA values were significantly higher in PSA > 2ng/ml, PSAdt ≤ 6 months and PSAvel ≥ 0.2ng/ml/month groups. Also, wbTV (p=0.039) and wbPSMA (p=0.020) were significantly higher in patients with ISUP grade group 5. PSA and PSAvel cut-offs (1.15 ng/ml and 0.065 ng/ml/month) were significantly associated with a positive PET/CT. CONCLUSION: Higher PSA values, unfavourable PSA kinetics and ISUP grade group 5 were robust predictive variables of larger tumour burden variables on [18F]DCFPyL PET/CT assessed by aPROMISE platform.

[18F]DCFPyL PET/CT versus [18F]fluoromethylcholine PET/CT in Biochemical Recurrence of Prostate Cancer (PYTHON): a prospective, open label, cross-over, comparative study.

PURPOSE: Primary objective was to compare the per-patient detection rates (DR) of [18F]DCFPyL versus [18F]fluoromethylcholine positron emission tomography/computed tomography (PET/CT), in patients with first prostate cancer (PCa) biochemical recurrence (BCR). Secondary endpoints included safety and impact on patient management (PM). METHODS: This was a prospective, open label, cross-over, comparative study with randomized treatment administration of [18F]DCFPyL (investigational medicinal product) or [18F]fluoromethylcholine (comparator). Men with rising prostate-specific antigen (PSA) after initial curative therapy were enrolled. [18F]DCFPyL and [18F]fluoromethylcholine PET/CTs were performed within a maximum time interval of 12 days. DR was defined as the percentage of positive PET/CT scans identified by 3 central imaging readers. PM was assessed by comparing the proposed pre-PET/CT treatment with the local treatment", defined after considering both PET/CTs. RESULTS: A total of 205 patients with first BCR after radical prostatectomy (73%; median PSA = 0.46 ng/ml [CI 0.16;27.0]) or radiation therapy (27%; median PSA = 4.23 ng/ml [CI 1.4;98.6]) underwent [18F]DCFPyL- and/or [18F]fluoromethylcholine -PET/CTs, between July and December 2020, at 22 European sites. 201 patients completed the study. The per-patient DR was significantly higher for [18F]DCFPyL- compared to [18F]fluoromethylcholine -PET/CTs (58% (117/201 patients) vs. 40% (81/201 patients), p < 0.0001). DR increased with higher PSA values for both tracers (PSA ≤ 0.5 ng/ml: 26/74 (35%) vs. 22/74 (30%); PSA 0.5 to ≤ 1.0 ng/ml: 17/31 (55%) vs. 10/31 (32%); PSA 1.01 to < 2.0 ng/ml: 13/19 (68%) vs. 6/19 (32%);PSA > 2.0: 50/57 (88%) vs. 39/57 (68%) for [18F]DCFPyL- and [18F]fluoromethylcholine -PET/CT, respectively). [18F]DCFPyL PET/CT had an impact on PM in 44% (90/204) of patients versus 29% (58/202) for [18F]fluoromethylcholine. Overall, no drug-related nor serious adverse events were observed. CONCLUSIONS: The primary endpoint of this study was achieved, confirming a significantly higher detection rate for [18F]DCFPyL compared to [18F]fluoromethylcholine, in men with first BCR of PCa, across a wide PSA range. [18F]DCFPyL was safe and well tolerated.

SUVmax to tumor perimeter distance: a robust radiomics prognostic biomarker in resectable non-small cell lung cancer patients.

OBJECTIVE: The purpose of this study was to evaluate the prognostic value of novel geometric variables obtained from pre-treatment [18F]FDG PET/CT with respect to classical ones in patients with non-small cell lung cancer (NSCLC). METHODS: Retrospective study including stage I-III NSCLC patients with baseline [18F]FDG PET/CT. Clinical, histopathologic, and metabolic parameters were obtained. After tumor segmentation, SUV and volume-based variables, global texture, sphericity, and two novel parameters, normalized SUVpeak to centroid distance (nSCD) and normalized SUVmax to perimeter distance (nSPD), were obtained. Early recurrence (ER) and short-term mortality (STM) were used as end points. Univariate logistic regression and multivariate logistic regression with respect to ER and STM were performed. RESULTS: A cohort of 173 patients was selected. ER was detected in 49/104 of patients with recurrent disease. Additionally, 100 patients died and 53 had STM. Age, pathologic lymphovascular invasion, lymph nodal infiltration, TNM stage, nSCD, and nSPD were associated with ER, although only age (aOR = 1.06, p = 0.002), pathologic lymphovascular invasion (aOR = 3.40, p = 0.022), and nSPD (aOR = 0.02, p = 0.018) were significant independent predictors of ER in multivariate analysis. Age, lymph nodal infiltration, TNM stage, nSCD, and nSPD were predictors of STM. Age (aOR = 1.05, p = 0.006), lymph nodal infiltration (aOR = 2.72, p = 0.005), and nSPD (aOR = 0.03, p = 0.022) were significantly associated with STM in multivariate analysis. Coefficient of variation (COV) and SUVmean/SUVmax ratio did not show significant predictive value with respect to ER or STM. CONCLUSION: The geometric variables, nSCD and nSPD, are robust biomarkers of the poorest outcome prediction of patients with NSCLC with respect to classical PET variables. KEY POINTS: • In NSCLC patients, it is crucial to find prognostic parameters since TNM system alone cannot explain the variation in lung cancer survival. • Age, lymphovascular invasion, lymph nodal infiltration, and metabolic geometrical parameters were useful as prognostic parameters. • The displacement grade of the highest point of metabolic activity towards the periphery assessed by geometric variables obtained from [18F]FDG PET/CT was a robust biomarker of the poorest outcome prediction of patients with NSCLC.

18F-FDG PET/CT in breast cancer: Evidence-based recommendations in initial staging.

Current guidelines do not systematically recommend 18F-FDG PET/CT for breast cancer staging; and the recommendations and level of evidence supporting its use in different groups of patients vary among guidelines. This review summarizes the evidence about the role of 18F-FDG PET/CT in breast cancer staging and the therapeutic and prognostic impact accumulated in the last decade. Other related aspects, such as the association of metabolic information with biology and prognosis are considered and evidence-based recommendations for the use of 18F-FDG PET/CT in breast cancer staging are offered. We systematically searched MEDLINE for articles reporting studies with at least 30 patients related to clinical questions following the Problem/Population, Intervention, Comparison, and Outcome framework. We critically reviewed the selected articles and elaborated evidence tables structuring the summarized information into methodology, results, and limitations. The level of evidence and the grades of recommendation for the use of 18F-FDG PET/CT in different contexts are summarized. Level III evidence supports the use of 18F-FDG PET/CT for initial staging in patients with recently diagnosed breast cancer; the diagnostic and therapeutic impact of the 18F-FDG PET/CT findings is sufficient for a weak recommendation in this population. In patients with locally advanced breast cancer, level II evidence supports the use of 18F-FDG PET/CT for initial staging; the diagnostic and therapeutic impact of the 18F-FDG PET/CT findings is sufficient for a strong recommendation in this population. In patients with recently diagnosed breast cancer, the metabolic information from baseline 18F-FDG PET/CT is associated with tumor biology and has prognostic implications, supported by level II evidence. In conclusion, 18F-FDG PET/CT is not recommended for staging all patients with early breast cancer, although evidence of improved regional and systemic staging supports its use in locally advanced breast cancer. Baseline tumor glycolytic activity is associated with tumor biology and prognosis.

18F-fluorodeoxyglucose positron emission tomography in the diagnosis of malignancy in patients with paraneoplastic neurological syndrome: a systematic review and meta-analysis.

PURPOSE: The detection of occult cancer in patients suspected of having a paraneoplastic neurological syndrome (PNS) poses a diagnostic challenge. The aim of our study was to perform a systematic review and meta-analysis to assess the diagnostic performance of FDG PET for the detection of occult malignant disease responsible for PNS. METHODS: A systematic review of the literature (MEDLINE, EMBASE, Cochrane, and DARE) was undertaken to identify studies published in any language. The search strategy was structured after addressing clinical questions regarding the validity or usefulness of the test, following the PICO framework. Inclusion criteria were studies involving patients with PNS in whom FDG PET was performed to detect malignancy, and which reported sufficient primary data to allow calculation of diagnostic accuracy parameters. When possible, a meta-analysis was performed to calculate the joint sensitivity, specificity, and detection rate for malignancy (with 95% confidence intervals [CIs]), as well as a subgroup analysis based on patient characteristics (antibodies, syndrome). RESULTS: The comprehensive literature search revealed 700 references. Sixteen studies met the inclusion criteria and were ultimately selected. Most of the studies were retrospective (12/16). For the quality assessment, the QUADAS-2 tool was applied to assess the risk of bias. Across 16 studies (793 patients), the joint sensitivity, specificity, and detection rate for malignancy with FDG PET were 0.87 (95% CI: 0.80-0.93), 0.86 (95% CI: 0.83-0.89), and 14.9% (95% CI: 11.5-18.7), respectively. The area under the curve (AUC) of the summary ROC curve was 0.917. Homogeneity of results was observed for sensitivity but not for specificity. Some of the individual studies showed large 95% CIs as a result of small sample size. CONCLUSIONS: The results of our meta-analysis reveal high diagnostic performance of FDG PET in the detection of malignancy responsible for PNS, not affected by the presence of onconeural antibodies or clinical characteristics.

Basal ¹8F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography as a prognostic biomarker in patients with locally advanced breast cancer.

AIM: To explore the relationship between basal (18) F-FDG PET/CT information in breast tumours and survival in locally advanced breast cancer (LABC). METHODS: This prospective, multicentre study included 198 women diagnosed with LABC. All patients underwent (18) F-FDG PET/CT prior to treatment. The maximum standardized uptake value (SUVmax) in tumor (T), lymph nodes (N) and the N/T ratio was obtained in all cases. Stage according to PET/CT imaging (metabolic stage) and conventional imaging techniques (clinical stage) was established. During follow-up, patient status was established (disease free status or not). The relationship between all the variables and overall survival (OS) and disease-free survival (DFS) was analysed using the Kaplan-Meier and Cox regression methods. A ROC analysis was performed to obtain a cut-off value of SUVmax that was useful in the prediction of outcome. RESULTS: The mean SUVmax ± SD values in the primary tumour, lymph nodes and the SUVmax N/T index were 7.40 ± 5.57, 4.17 ± 4.74 and 0.73 ± 1.20, respectively. Higher semiquantitative metabolic values were found in more advanced metabolic and clinical stages. During follow-up, 78.4 % of patients were free of disease. Significant relationships were observed between SUVT and SUVN and patient status. With respect to OS and DFS, significant differences were detected for the metabolic stage. Kaplan-Meier analysis revealed that using the cut-off values, a primary-tumour SUVmax ≥ 6.05 or a nodal SUVmax ≥2.25 were significantly correlated with DFS and OS. CONCLUSION: PET imaging with (18) F-FDG offers prognostic information for LABC that can be obtained preoperatively and noninvasively.

Clinical utility of (18)F-fluorocholine positron-emission tomography/computed tomography (PET/CT) in biochemical relapse of prostate cancer after radical treatment: results of a multicentre study.

OBJECTIVE: To evaluate (18)F-fluorocholine positron-emission tomography (PET)/computed tomography (CT) in restaging patients with a history of prostate adenocarcinoma who have biochemical relapse after early radical treatment, and to correlate the technique's disease detection rate with a set of variables and clinical and pathological parameters. PATIENTS AND METHODS: This was a retrospective multicentre study that included 374 patients referred for choline-PET/CT who had biochemical relapse. In all, 233 patients who met the following inclusion criteria were analysed: diagnosis of prostate cancer; early radical treatment; biochemical relapse; main clinical and pathological variables; and clinical, pathological and imaging data needed to validate the results. Criteria used to validate the PET/CT: findings from other imaging techniques, clinical follow-up, treatment response and histological analysis. Different statistical tests were used depending on the distribution of the data to correlate the results of the choline-PET/CT with qualitative [T stage, N stage, early radical prostatectomy (RP) vs other treatments, hormone therapy concomitant to choline-PET/CT] and quantitative [age, Gleason score, prostate-specific antigen (PSA) levels at diagnosis, PSA nadir, PSA level on the day of the choline-PET/CT (Trigger PSA) and PSA doubling time (PSADT)] variables. We analysed whether there were independent predictive factors associated with positive PET/CT results. RESULTS: Choline-PET/CT was positive in 111 of 233 patients (detection rate 47.6%) and negative in 122 (52.4%). Disease locations: prostate or prostate bed in 26 patients (23.4%); regional and/or distant lymph nodes in 52 (46.8%); and metastatic bone disease in 33 (29.7%). Positive findings were validated by: results from other imaging techniques in 35 patients (15.0%); at least 6 months of clinical follow-up in 136 (58.4%); treatment response in 24 (10.3%); histological analysis of lesions in 17 (7.3%); and follow-up plus imaging results in 21 (9.0%). The statistical analysis of qualitative variables, corresponding to patients' clinical characteristics, and the positive/negative final PET/CT results revealed that only whether or not early treatment with RP was done was statistically significant (P < 0.001), with the number of positive results higher in patients who did not undergo a RP. Among the quantitative variables, Gleason score, Trigger PSA and PSADT clearly differentiated the two patient groups (positive and negative choline-PET/CT: P = 0.010, P = 0.001 and P = 0.025, respectively). A Gleason score of <5 or ≥ 8 clearly differentiated positive from negative PET. Trigger PSA: mean of 8 ng/mL for positive PET/CT vs 2.8 ng/mL for negative PET/CT; PSADT: mean of 8 months for positive vs 12.6 months for negative. The optimal threshold values were: 3 ng/mL for Trigger PSA level and 6 months for PSADT (Youden index/receiver operating characteristic curve). Analysing these two variables together showed that PSADT was more conclusive in patients with lower Trigger PSA levels. Analysing variables by location showed that only PSADT was able to differentiate between those with disease confined to the prostate compared with the other two locations (lymph nodes and bone), with shorter PSADT in these two, which was statistically significant (P < 0.002). In the patient group with a PSA level of <1.5 ng/mL, 30.8% had the disease, 7% of whom had metastatic bone disease. In the multivariate logistic regression, the risks factors that were clearly independent for those with positive PET/CT were: PSA level of >3 ng/mL, no early RP, and Gleason score of ≥ 8. CONCLUSION: Our results support the usefulness of (18)F-fluorocholine PET/CT in biochemical relapse of prostate cancer after radical treatment, with an overall disease detection rate close to 50%, and it can be recommended as first-line treatment. As mentioned above, besides Trigger PSA levels, there are other clinical and pathological variables that need to be considered so as to screen patients properly and thus minimise the number of nodular lesions and increase the diagnostic accuracy of the examination.

Heterogeneity in [18F]fluorodeoxyglucose positron emission tomography/computed tomography of non-small cell lung carcinoma and its relationship to metabolic parameters and pathologic staging.

To investigate the relationships between tumor heterogeneity, assessed by texture analysis of [18F]fluorodeoxyglucose-positron emission tomography (FDG-PET) images, metabolic parameters, and pathologic staging in patients with non-small cell lung carcinoma (NSCLC). A retrospective analysis of 38 patients with histologically confirmed NSCLC who underwent staging FDG-PET/computed tomography was performed. Tumor images were segmented using a standardized uptake value (SUV) cutoff of 2.5. Five textural features, related to the heterogeneity of gray-level distribution, were computed (energy, entropy, contrast, homogeneity, and correlation). Additionally, metabolic parameters such as SUVmax, SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG), as well as pathologic staging, histologic subtype, and tumor diameter, were obtained. Finally, a correlation analysis was carried out. Of 38 tumors, 63.2% were epidermoid and 36.8% were adenocarcinomas. The mean ± standard deviation values of MTV and TLG were 30.47 ± 25.17 mL and 197.81 ± 251.11 g, respectively. There was a positive relationship of all metabolic parameters (SUVmax, SUVmean, MTV, and TLG) with entropy, correlation, and homogeneity and a negative relationship with energy and contrast. The T component of the pathologic TNM staging (pT) was similarly correlated with these textural parameters. Textural features associated with tumor heterogeneity were shown to be related to global metabolic parameters and pathologic staging.

Heterogeneity in [¹8F]fluorodeoxyglucose positron emission tomography/computed tomography of non-small cell lung carcinoma and its relationship to metabolic parameters and pathologic staging.

To investigate the relationships between tumor heterogeneity, assessed by texture analysis of [18F]fluorodeoxyglucose-positron emission tomography (FDG-PET) images, metabolic parameters, and pathologic staging in patients with non-small cell lung carcinoma (NSCLC). A retrospective analysis of 38 patients with histologically confirmed NSCLC who underwent staging FDG-PET/computed tomography was performed. Tumor images were segmented using a standardized uptake value (SUV) cutoff of 2.5. Five textural features, related to the heterogeneity of gray-level distribution, were computed (energy, entropy, contrast, homogeneity, and correlation). Additionally, metabolic parameters such as SUVmax, SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG), as well as pathologic staging, histologic subtype, and tumor diameter, were obtained. Finally, a correlation analysis was carried out. Of 38 tumors, 63.2% were epidermoid and 36.8% were adenocarcinomas. The mean ± standard deviation values of MTV and TLG were 30.47 ± 25.17 mL and 197.81 ± 251.11 g, respectively. There was a positive relationship of all metabolic parameters (SUVmax, SUVmean, MTV, and TLG) with entropy, correlation, and homogeneity and a negative relationship with energy and contrast. The T component of the pathologic TNM staging (pT) was similarly correlated with these textural parameters. Textural features associated with tumor heterogeneity were shown to be related to global metabolic parameters and pathologic staging.

Glycolytic activity with 18F-FDG PET/CT predicts final neoadjuvant chemotherapy response in breast cancer.

The purpose of the present study is to explore the relation between glycolytic metabolism assessed by (18)F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) and final neoadjuvant chemotherapy (NC) response in locally advanced breast tumors. Of women with breast cancer, 126 were prospectively evaluated. All patients underwent (18)F-FDG PET/CT previous to NC. Standard uptake value (SUV) max was calculated in the primary tumor. After NC, residual primary tumor specimen was histopathologically classified according to Miller and Payne tumor regression grades (TRG), from G1 to G5 and in response groups as good responders (G4 or G5), partial responders (G2 or G3), and non-responders (G1). Furthermore, residual lesions were classified following a binary assessment as responders (G4 or G5) and non-responders (the rest of cases). The relationship between SUV max with TRG and response groups was evaluated. Of tumors, 127 were assessed (a patient had bilateral breast lesions). TRG were as follows: G1 (27), G2 (27), G3 (32), G4 (11), and G5 (30). Forty-one were classified as good responders, 59 as partial responders, and 27 as non-responders. For the binary assessment, 41 lesions were classified as responders and 86 as non-responders. We found statistical differences (p=0.02) between the mean SUV max and TRG with greater SUV values for G5 compared to the other TRG. Good responders showed greater mean SUV max ± SD compared to partial responders and non-responders (10.51 ± 6.64 for good responders, 6.94 ± 5.81 for partial responders, and 5.23 ± 2.76 for non-responders; p=0.001). Baseline tumor metabolism assessing by FDG PET/CT was associated with the final histopathologic status after neoadjuvant chemotherapy, with greater SUV max values for good responders compared to the less responder cancers.

Early and delayed prediction of axillary lymph node neoadjuvant response by (18)F-FDG PET/CT in patients with locally advanced breast cancer.

PURPOSE: To determine the utility of (18)F-FDG (FDG) PET/CT performed in an early and delayed phase during neoadjuvant chemotherapy in the prediction of lymph node histopathological response in patients with locally advanced breast cancer. METHODS: FDG PET/CT studies performed in 76 patients (mean age 53 years) at baseline (PET-1), after the second course of chemotherapy (PET-2) and after the last course of chemotherapy (PET-3) were prospectively analysed. Inclusion criteria were lymph node involvement detected by PET/CT and non-sentinel node biopsy before or after the baseline PET/CT scan. Following the recommendations of the 12th International Breast Conference (St. Gallen), the patients were divided into five subgroups in relation to biological prognostic factors by immunohistochemistry. For diagnosis visual and semiquantitative analyses was performed. Absence of detectable lymph node uptake on the PET-2 or PET-3 scan with respect to the PET-1 scan was considered metabolic complete response (mCR). Lymph nodes were histopathologically classified according the lymph node regression grade and in response groups as pathological complete response (pCR) or not pCR (type A/D or B/C of the Smith grading system, respectively). ROC analysis was performed to determine a cut-off value of Δ% SUV1-2 and SUV1-3 for prediction of nodal status after chemotherapy. An association between mCR and pCR was found (Cohen's kappa analysis), and associations between phenotypes and metabolic behaviour and the final histopathological status were also found. RESULTS: Lymph node pCR was seen in 34 patients. The sensitivity, specificity, and positive and negative predictive values of PET-2 and PET-3 in establishing the final status of the axilla after chemotherapy were 52 %, 45 %, 50 % and 47 %, and 33 %, 84 %, 67 % and 56 %, respectively. No significant relationship was observed between mCR on PET-2 and PET-3 and pCR (p = 0.31 and 0.99, respectively). Lymph node metabolism on PET-1 was not able to predict the final histopathological status, whereas basal carcinomas showed a higher rate of pCR (70.6 %) than the other groups (p = 0.03). CONCLUSION: FDG PET/CT seems to have limitations in both the early and delayed evaluation of lymph node status after chemotherapy, with reduced predictive values.

[Red flags of cardiac amyloidosis in patients with spinal stenosis and yellow ligament hypertrophy]. / «Banderas rojas¼ de amiloidosis cardiaca en pacientes con estenosis de canal lumbar e hipertrofia de ligamento amarillo.

INTRODUCTION: Studies addressing the prevalence of cardiac amyloidosis (CA) among patients with spinal stenosis (SS) are lacking. The identification of the red flags (RF) of CA could lead to early detection of cases of CA. The primary objective of this study was to address the prevalence of RF of CA among patients with SS. METHODS: Transversal study including consecutive cases with SS and yellow ligament hypertrophy (YLH). A clinical assessment that included electrocardiogram, echocardiogram and urine and blood test was performed. A clinical suspicion of CA was defined by the presence of left ventricular hypertrophy plus any RF. RESULTS: One hundred and three patients with SS and YLH were assessed. The prevalence of RF was high: heart failure: 18.4%; aortic stenosis: 1.9%; carpal tunnel syndrome: 7.8%; bicipital tendon rupture: 1.9%; arterial hypotension: 17.4%; polyneuropathy symptoms: 51.5%; pseudoinfarction pattern: 3.9%; low voltages: 15.5%; conduction abnormalities: 15.5%; decreased longitudinal strain: 25.3%; apical sparing pattern: 3.9%. The 57.3% of the cohort met the CA suspicion criteria. CONCLUSION: The prevalence of RF of CA is high among patients with SS and YLH. A high proportion of patients met the CA suspicion criteria.

Analytical performance validation of aPROMISE platform for prostate tumor burden, index and dominant tumor assessment with 18F-DCFPyL PET/CT. A pilot study.

To validate the performance of automated Prostate Cancer Molecular Imaging Standardized Evaluation (aPROMISE) in quantifying total prostate disease burden with 18F-DCFPyL PET/CT and to evaluate the interobserver and histopathologic concordance in the establishment of dominant and index tumor. Patients with a recent diagnosis of intermediate/high-risk prostate cancer underwent 18F-DCFPyL-PET/CT for staging purpose. In positive-18F-DCFPyL-PET/CT scans, automated prostate tumor segmentation was performed using aPROMISE software and compared to an in-house semiautomatic-manual guided segmentation procedure. SUV and volume related variables were obtained with two softwares. A blinded evaluation of dominant tumor (DT) and index tumor (IT) location was assessed by both groups of observers. In histopathological analysis, Gleason, International Society of Urological Pathology (ISUP) group, DT and IT location were obtained. We compared all the obtained variables by both software packages using intraclass correlation coefficient (ICC) and Cohen's kappa coefficient (k) for the concordance analysis. Fifty-four patients with a positive 18F-DCFPyL PET/CT were evaluated. The ICC for the SUVmax, SUVpeak, SUVmean, tumor volume (TV) and total lesion activity (TLA) was: 1, 0.833, 0.615, 0.494 and 0.950, respectively (p < 0.001 in all cases). For DT and IT detection, a high agreement was observed between both softwares (k = 0.733; p < 0.001 and k = 0.812; p < 0.001, respectively) although the concordances with histopathology were moderate (p < 0001). The analytical validation of aPROMISE showed a good performance for the SUVmax, TLA, DT and IT definition in comparison to our in-house method, although the concordance was moderate with histopathology for DT and IT.

Second radioiodine treatment in patients with differentiated thyroid carcinoma: Causes and effects.

INTRODUCTION: Patients with incomplete response to initial therapy of thyroid cancer can be managed with ongoing observation or potentially additional therapies. Our aim was to assess the effect of a second radioactive iodine treatment (RAIT) and its relationship with causes and clinical variables. MATERIAL AND METHODS: Patients undergoing a second RAIT for biochemical or structural incomplete response to initial therapy of DTC were retrospectively included (n=120). They were categorised based on the American Thyroid Association (ATA) classification of response to initial therapy. Patients were reclassified in the following 6-18 months after second RAIT based on imaging findings and measurements of thyroglobulin and antithyroglobulin antibody levels. The associations of a downgrading of response category and progression-free survival (PFS), and the related variables, were evaluated. RESULTS: Sixty-six patients (55%) had a downgrading on ATA response category after second RAIT. A significant interdependence of causes for second RAIT and outcomes was found (χ2=29.400, p=0.001), with patients with neck reoperation showing a higher rate of indeterminate or excellent responses. A significant association between ATA response to second RAIT and absence of structural progression was found (χ2=44.914, p<0.001), with less structural progression in patients with downgrading on ATA response (χ2=30.914, p<0.001). There was also significant interdependence to some clinical variables, such as AJCC stage (χ2=8.460, p=0.015), ATA risk classification (χ2=10.694, p=0.005) and initial N stage (χ2=8.485, p=0.004). CONCLUSIONS: In selected cases, a second RAIT could lead to more robust responses with a potential improvement in prognosis in patients with incomplete response to initial DTC treatment.

Dual-Time-Point 18F-FDG PET/CT in Infective Endocarditis: Impact of Delayed Imaging in the Definitive Diagnosis of Endocarditis.

Infective endocarditis (IE) is a major public health condition due to the associated high morbidity and mortality. Our objective was to evaluate the utility of dual-time 2-deoxy-2-[18F] fluoro-D-glucose (18F-FDG) Positron Emission Tomography/Computed Tomography (PET/CT) imaging in the diagnosis of active IE in patients with suspected native valve endocarditis (NVE) and prosthetic valve endocarditis (PVE). For this purpose, a retrospective study was carried out, including patients suspicious of NVE or PVE who underwent a dual-time-point 18F-FDG PET/CT. A final diagnosis was established by the Endocarditis Team after patient follow-up using all the available findings. Sixty-nine patients were assessed. A final diagnosis of NVE was established in 3 patients of the 34 by 18F-FDG PET/CT and in the case of PVE was established in 20 patients of the 35. A statistically significant association was found when evaluating the association between PET diagnosis at early acquisition and final diagnosis of IE (χ2 = 30.198, p < 0.001) and PET diagnosis at delayed acquisition for final diagnosis of IE (χ2 = 9.412, p = 0.002). Delayed PET/CT imaging determined the IE diagnosis in 16/58 of the studies. In conclusion, delayed 18F-FDG PET/CT imaging seems to be useful in improving the definitive diagnosis of IE.

Molecular subtypes of breast cancer: metabolic correlation with ¹8F-FDG PET/CT.

PURPOSE: To determine whether the metabolic features of breast tumours differ among molecular subtypes. METHODS: This prospective study included 168 women diagnosed with locally advanced breast cancer. PET/CT was requested in the initial staging before neoadjuvant treatment (multicentre study, FISCAM grant). All patients underwent an ¹8F-FDG PET/CT scan with a dual time-point acquisition. Both examinations (PET-1 and PET-2) were evaluated qualitatively and semiquantitatively with calculation of SUVmax (SUV-1 and SUV-2, respectively), and the percentage variation in the SUVs and retention indexes (RI) between PET-1 and PET-2 in the breast tumour were calculated. Biological prognostic parameters, including the steroid receptor status, HER-2 expression, proliferation rate (Ki-67) and grading, were determined from primary tumour tissue. Tumour subtypes were classified following the recommendations of the 12th International Breast Conference, by immunohistochemical surrogates as luminal A, luminal B-HER2(-), luminal B-HER2(+), HER2(+) or basal. Metabolic semiquantitative parameters and molecular subtypes were correlated. RESULTS: Of the 168 tumours, 151 were classified: 16 were luminal A, 53 were luminal B-HER2(-), 29 were luminal B-HER2(+), 18 were HER2(+) and 35 were basal. There were significant differences between SUV-1 and SUV-2 and the different subtypes, with higher SUVs in HER2(+) and basal tumours. No significant differences were found with respect to RI. CONCLUSION: Semiquantitative metabolic parameters showed statistically significant differences among the molecular subtypes of the tumours evaluated. Therefore, there seems to be a relationship between molecular and glycolytic phenotypes.

Semi-quantitative lymph node assessment of (18)F-FDG PET/CT in locally advanced breast cancer: correlation with biological prognostic factors.

PURPOSE: The aim of this study was to analyse the correlation between dual-time-point (18)F-2-deoxy-2-fluoro-D-glucose (FDG) uptakes in lymph nodes assessed by positron emission tomography (PET)/CT and histopathological and immunohistochemical prognostic factors. METHODS: Seventy-five women with locally advanced breast cancer were prospectively evaluated. PET/CT was requested in the initial staging previous to adjuvant chemotherapy (multicentre study). All of the patients underwent (18)F-FDG PET/CT with a dual-time-point acquisition. Both examinations were evaluated qualitatively and semi-quantitatively with calculation of maximum standardized uptake values (SUV(max)) in PET-1 (SUV-1) and in PET-2 (SUV-2) and the percentage variation of the SUV or retention index (RI) between PET-1 and PET-2 in lymph nodes with the greater (18)F-FDG uptake. The biological prognostic parameters such as the steroid receptor status, p53 and HER2 expression, proliferation rate (Ki-67) and grading were determined from tissue of the primary tumour. Metabolic and biological parameters were correlated using Spearman's rank-order correlation coefficient and Mann-Whitney U and Kruskal-Wallis tests. RESULTS: Negative receptor status was correlated with higher SUV-1, SUV-2 and RI in lymph nodes. The results were significant for progesterone receptor status. p53 over-expression and triple-negative status were associated with greater semi-quantitative parameters in lymph nodes. Higher tumoural grades were related with greater semi-quantitative parameters (p > 0.05). CONCLUSION: Biological factors of bad prognosis were correlated with higher semi-quantitative metabolic values in lymph nodes. Therefore these results appear to reveal biological significance of lymph node (18)F-FDG accumulation.

Brain Nocardiosis Defined by 18 F-Fluorocholine PET/CT.

ABSTRACT: Nocardia infection (nocardiosis) is usually acquired by inhalation; so pulmonary nocardiosis is the most common clinical presentation. Extrapulmonary localization occurs through hematogenous dissemination or contiguous spread. Nocardia can involve the central nervous system in a very reduced number of patients, mainly in immunocompromised. We present a case of a 56-year-old woman with a history of aggressive systemic mastocytosis, treated with chemotherapy 1 year ago. Patient reported intense headache, disorientation, and blurry vision without other symptoms being diagnosed with a rare brain nocardiosis by Nocardia cerradoensis . Neither bacteremia nor pulmonary involvement was detected. Brain PET/CT illustrated 18 F-fluorocholine avidity on brain abscesses.

Head-to-Head Comparison of [18F]F-choline and Imaging of Prostate-Specific Membrane Antigen, Using [18F]DCFPyL PET/CT, in Patients with Biochemical Recurrence of Prostate Cancer.

PURPOSE: To analyse diagnostic and therapeutic impact of molecular imaging TNM (miTNM) stage obtained with [18F]DCFPyL versus [18F]F-choline in head-to-head comparison in biochemical recurrence (BCR) of prostate cancer (PCa). MATERIAL AND METHODS: Patients with BCR of PCa after radical treatment with previous [18F]F-choline-PET/CT (negative or oligometastatic disease) were recruited to [18F]DCFPyL-PET/CT. Patients were classified according to: grade group, European Association of Urology classification, PSA, PSA doubling time (PSAdt) and PSA velocity (PSAvel). The overall detection rate (DR) and miTNM stage according to PROMISE criteria were assessed for both radiotracers and also correlated (Kappa). The influence of PSA and kinetics on both PET/CT (DR and miTNM) and predictive value of unfavourable kinetics on miTNM were determined. Cut-off PSA, PSAdt and PSAvel values able to predict PET/CT results were determined. Change in miTNM and treatment derived from [18F]DCFPyL information compared with [18F]F-choline were also evaluated. RESULTS: We studied 138 patients. [18F]DCFPyL showed a higher DR than [18F]F-choline (64.5% versus 33.3%) with a fair agreement. [18F]DCFPyL and [18F]F-choline detected T in 33.3% versus 19.6%, N in 27.5% versus 13.8%, and M in 30.4% versus 8.7%. Both tracers' DR showed significant associations with PSA and PSAvel. Significant association was only found between miTNM and PSA on [18F]F-choline-PET/CT (p = 0.033). For [18F]F-choline and [18F]DCFPyL-PET/CT, a PSAdt cut-off of 4.09 and 5.59 months, respectively, were able to predict M stage. [18F]DCFPyL changed therapeutic management in 40/138 patients. CONCLUSIONS: [18F]DCFPyL provides a higher DR and superior miTNM staging than [18F]F-choline in restaging BCR, especially with high PSA and unfavourable PSA kinetics, showing a fair agreement to [18F]F-choline.

Diagnostic and therapeutic impact of PET/CT with 18F-DCFPyL versus 18F-Fluorocholine in initial staging of intermediate-/high-risk prostate cancer: a pilot study.

AIM: To assess the diagnostic and therapeutic impact of PET/CT with 18F-DCFPyL with respect to 18F-Fluorocholine in initial staging of intermediate-/high-risk prostate cancer (PCa). MATERIAL AND METHODS: Patients with recent diagnosis of intermediate-/high-risk PCa without androgen deprivation therapy and previous 18F-Fluorocholine-PET/CT (negative for extraprostatic disease or with oligometastatic disease) were referred to 18F-DCFPyL-PET/CT. Patients' disease characteristic as grade group, D'Amico risk category (intermediate/high), prostate-specific antigen (PSA) closest to PET/CTs and its kinetics were obtained. The overall detection rate (DR) and molecular imaging TNM (miTNM) stage according to the prostate cancer molecular imaging standardized evaluation (PROMISE) criteria were assessed for both radiotracers, and their concordance (Kappa coefficient) was analyzed. The diagnostic and therapeutic impact of 18F-DCFPyL with respect to 18F-Fluorocholine was evaluated. RESULTS: Fifty-eight patients were analyzed (84.5% high-risk). 18F-Fluorocholine showed a higher DR than 18F-DCFPyL of prostate gland involvement (100% versus 93.1%) and pelvic node disease (37.9% versus 31%; k = 0.436, p = 0.001). On the other hand, 18F-DCFPyL-PET/CT showed a higher DR of metastatic disease than 18F-Fluorocholine-PET/CT, 9/58 patients (15.5%): 3 M1a, 5 M1b and 1 M1c) versus 5/58 (8.6%) patients: 1 M1a and 4 M1b), k = 0.426; p = 0.001. No significant association was found between clinical characteristics (grade group, risk category, PSA level and kinetic) and 18F-Fluorocholine or 18F-DCFPyL results. The results of 18F-DCFPyL-PET/CT modified the previously planned treatment compared to 18F-Fluorocholine-PET/CT in 13 patients (22.4%). CONCLUSIONS: 18F-Fluorocholine and 18F-DCFPyL PET/CT showed a similar DR of prostate gland and lymph node involvement, although with moderate concordance for the latter. 18F-DCFPyL was superior to 18F-Fluorocholine in detecting regional and distant metastasis with a therapeutic impact in one of every five patients.