Metabolic Tumor Volume on 18-Fluorodeoxyglucose Positron Emission Tomography as a Prognostic Marker of Survival in Patients With Locally Advanced or Metastatic Neuroendocrine Neoplasms Treated With 177Lutetium-DOTA-Octreotate Peptide Receptor Radionuclide Therapy.

OBJECTIVE: We investigated metabolic tumor volume (MTV) and total lesion glycolysis (TLG) on pre-treatment FDG-PET as prognostic markers for survival in patients with metastatic neuroendocrine neoplasms (NENs) receiving peptide receptor radionuclide therapy (PRRT). METHODS: A retrospective review of patients with metastatic NENs receiving PRRT was undertaken. Pre-treatment FDG-PET images were analyzed and variables collected included MTV and TLG (dichotomized by median into high vs low). Main Outcomes were overall survival (OS) and progression-free survival (PFS) by MTV and TLG (high vs low). RESULTS: One hundred five patients were included. Median age was 64 years (50% male). Main primary NEN sites were small bowel (43.8%) and pancreas (40.0%). Median MTV was 3.8 mL and median TLG was 19.9. Dichotomization formed identical cohorts regardless of whether MTV or TLG were used. Median OS was 72 months; OS did not differ based on MTV/TLG high versus low (47.4 months vs not reached; hazard ratio, 0.43; 95% confidence interval [CI], 0.18-1.04; P = 0.0594). Median PFS was 30.4 months; PFS differed based on MTV/TLG high versus low (21.6 months vs 45.7 months; hazard ratio, 0.35; 95% CI, 0.19-0.64; P = 0.007). CONCLUSIONS: Low MTV/TLG on pre-treatment FDG-PET was associated with longer PFS in metastatic NEN patients receiving PRRT.

The quality of clinical trials in neuroendocrine tumours; have we learnt from our mistakes? An evaluation of phase II and phase III clinical trials.

The quality and reporting of neuroendocrine tumour (NET) clinical trials has previously been found to be heterogeneous impairing trial interpretability. We aimed to perform an updated review of the quality of phase II/III clinical trials in NET to assess if trial design and reporting have improved since 2011. We performed a PubMed search for phase II/III trials evaluating systemic anticancer therapies or liver-directed therapies published between 2011 and 2018. Data collected comprised administrative data, study population characteristics, endpoints, reporting and statistical design parameters, and results. Sixty studies were included (5218 patients): 50 phase II and 10 phase III trials. Study populations were heterogeneous: 52% of trials allowed tumours from various primary sites, 28% allowed both well- and poorly-differentiated tumour morphology or did not specify, and 57% did not report proliferative indices and/or tumour grade in ≥80% of the study population. Only 36% of trials mandated radiological disease progression on participant enrolment using a validated measure. Statistical design and primary endpoint were clearly defined in 67% and 88% of trials, respectively. Toxicity (88%), radiological response rate (85%) and progression-free survival/time to progression (82%) were well reported in a majority of trials, but health-related quality of life was included in the minority. Of the randomised trials (n = 11), study populations were more homogeneous and study design was more often clearly defined; however, only 45% mandated radiological progression at baseline as measured per Response Evaluation Criteria In Solid Tumours, and reporting of health-related quality of life (55%) remained suboptimal. The design and reporting of NET clinical trials, predominantly of single-arm phase II trials, remains suboptimal and has not considerably improved over time despite the growth in our knowledge of the biology and unique characteristics of NETs. Higher quality is seen in randomised trials, although certain design and reporting elements remain inadequate in some studies. We must prioritise the design and conduct of NET clinical trials to effectively inform future research and guide practice change.

A Longitudinal Investigation of Inflammatory Markers in Colorectal Cancer Patients Perioperatively Demonstrates Benefit in Serial Remeasurement.

OBJECTIVE: To characterize the longitudinal course of the systemic inflammatory response (SIR) throughout the perioperative period. To investigate whether postoperative changes in the neutrophil-to-lymphocyte ratio (NLR) or lymphocyte-to-monocyte ratio (LMR) when compared with preoperative levels ('conversion') are associated with survival differences in colorectal cancer patients undergoing resection. BACKGROUND: Recent evidence suggests that preoperative measurements of markers of the SIR including the NLR and LMR are prognostic. However, a few data exist evaluating longitudinal changes in the SIR especially in regards to their association with surgical interventions, optimal timing of assessment, and their effect on patient survival. METHODS: Data from 6 hospitals from January 1998 to December 2012 were retrospectively collected. We examined 2280 patients with complete data. For the subgroup analysis investigating conversion, we examined 587 patients with full preoperative and postoperative data from 21 to 56 days postoperative. Patients were stratified into 4 groups for analysis of conversion in a multivariate Cox-regression model. RESULTS: A longitudinal profile for the perioperative NLR and LMR was clearly characterized identifying an optimal period of remeasurement at 21 to 56 days postoperation. In multivariate analysis both NLR change group (P < 0.001) and LMR change group (P < 0.001) were independently associated with overall survival. For both biomarkers, patients with both a low preoperative and postoperative inflammatory state had the best survival. A change from the preoperative to postoperative inflammatory state was associated with a survival difference. CONCLUSIONS: This study characterizes the perioperative SIR profile and provides evidence for the remeasurement of SIR biomarkers postoperatively at 21 to 56 days for further prognostication.

Clinical and imaging-based prognostic factors in radioembolisation of liver metastases from colorectal cancer: a retrospective exploratory analysis.

BACKGROUND: The aim of this study was to investigate the relationship between absorbed dose and response of colorectal cancer liver metastases treated with [90Y]-resin microspheres and to explore possible clinical and imaging derived prognostic factors. METHODS: FDG PET/CT was used to measure response of individual lesions to a measured absorbed dose, derived from post-treatment 90Y PET imaging. Predicted dose was also derived from planning [99mTc]-MAA SPECT data. Peak standardised uptake value and total lesion glycolysis (TLG) were explored as response measures, and compared to dose metrics including average dose (D avg), biologically effective dose, minimum dose to 70% of lesion volume and volume receiving at least 50 Gy. Prognostic factors examined included baseline TLG, RAS mutation status, FDG heterogeneity and dose heterogeneity. In an exploratory analysis, response and clinico-pathological variables were evaluated and compared to overall survival. RESULTS: Sixty-three lesions were analysed from 22 patients. Poor agreement was seen between predicted and measured dose values. TLG was a superior measure of response, and all dose metrics were significant prognostic factors, with a D avg of ~50 Gy derived as the critical threshold for a significant response (>50% reduction in TLG). No significant correlation was found between baseline TLG or RAS mutation status and response. Measured dose heterogeneity was a significant prognostic factor and when combined with D avg had a positive predictive value for response >80%. In the exploratory analysis for prognostic factors of survival, low hepatic tumour burden and mean reduction in TLG >65% were independently associated with improved overall survival. CONCLUSIONS: Lesions receiving an average dose greater than 50 Gy are likely to have a significant response. For lesions receiving less than 50 Gy, dose heterogeneity is a significant prognostic factor. Lesions receiving an average dose less than 20 Gy are unlikely to respond. A reduction in TLG may be associated with improved overall survival.

In vivo quantification of (177)Lu with planar whole-body and SPECT/CT gamma camera imaging.

BACKGROUND: Advances in gamma camera technology and the emergence of a number of new theranostic radiopharmaceutical pairings have re-awakened interest in in vivo quantification with single-photon-emitting radionuclides. We have implemented and validated methodology to provide quantitative imaging of (177)Lu for 2D whole-body planar studies and for 3D tomographic imaging with single-photon emission computed tomography (SPECT)/CT. METHODS: Whole-body planar scans were performed on subjects to whom a known amount of [(177)Lu]-DOTA-octreotate had been administered for therapy. The total radioactivity estimated from the images was compared with the known amount of the radionuclide therapy administered. In separate studies, venous blood samples were withdrawn from subjects after administration of [(177)Lu]-DOTA-octreotate while a SPECT acquisition was in progress and the concentration of the radionuclide in the venous blood sample compared with that estimated from large blood pool structures in the SPECT reconstruction. The total radioactivity contained within an internal SPECT calibration standard was also assessed. RESULTS: In the whole-body planar scans (n = 28), the estimated total body radioactivity was accurate to within +4.6 ± 5.9 % (range -17.1 to +11.2 %) of the correct value. In the SPECT reconstructions (n = 12), the radioactivity concentration in the cardiac blood pool was accurate to within -4.0 ± 7.8 % (range -16.1 to +7.5 %) of the true value and the internal standard measurements (n = 89) were within 2.0 ± 8.5 % (range -16.3 to +24.2 %) of the known amount of radioactivity contained. CONCLUSIONS: In our hands, state-of-the-art hybrid SPECT/CT gamma cameras were able to provide accurate estimates of in vivo radioactivity to better than, on average, ±10 % for use in biodistribution and radionuclide dosimetry calculations.