Karin Stellamans

SIRT of liver metastases: physiological and pathophysiological considerations

Available literature on the differences in circulation and microcirculation of normal liver and liver metastases as well as in rheology of the different radiolabelled microspheres [99mTc-labelled macroaggregates of albumin (MAA), 90Y-TheraSpheres and 90Y-SIR-spheres] used in selective internal radiation therapy (SIRT) are reviewed and implications thereof on the practice of SIRT discussed. As a result of axial accumulation and skimming, large microspheres are preferentially deposited in regions of high flow, whereas smaller microspheres are preferentially diverted to regions of low flow. As flow to normal liver tissue is considerably variable between segments and also within one segment, microspheres will be delivered heterogeneously within the microvasculature of normal liver tissue. This non-uniformity in microsphere distribution in normal liver tissue has a significant “liver-sparing” effect on the dose distribution of 90Y-labelled microspheres. Arterial flow to liver metastases is most pronounced in the hypervascular rim of metastases, followed by the smaller metastases and finally by the central hypoperfused region of the larger metastases. Because of the wide variability in size of labelled MAAs and because of the skimming effect, existing differences in flow between metastatic lesions of variable size are likely exaggerated on 99mTc-MAA scintigraphy when compared to 90Y-TheraSpheres and 90Y-SIR-spheres (smaller variability in size and probably also in specific activity). Ideally, labelled MAAs would contain a size range similar to that of 90Y-SIR-spheres or 90Y-TheraSpheres. Furthermore, the optimal number of MAA particles to inject for the pretreatment planning scintigraphy warrants further exploration as it was shown that concentrated suspensions of microspheres produce more optimal tumour to normal liver distribution ratios. Finally, available data suggest that the flow-based heterogeneous distribution of microspheres to metastatic lesions of variable size might be optimized, that is rendered more homogeneous, through the combined use of angiotensin II and degradable starch microspheres.

Predictors of baseline cancer-related cognitive impairment in cancer patients scheduled for a curative treatment.

Recent research in the field of cancer‐related cognitive impairments (CRCI) has shown CRCI presentation prior to treatment initiation. Some have attributed these problems to worry and fatigue, whereas others have suggested an influence of age, IQ, and other psychosocial and medical factors.

Prätherapeutische quantitative VOI-Analyse von Lebermetastasen

UNLABELLED Using quantitive VOI analysis, the percentage (99m)Tc-MAA uptake and SUVmax and mean values of liver metastases obtained prior to SIRT were related to treatment response using both a lesion-based and clinical dichotomous approach. Based on the VOI % of (99m)Tc-MAA activity, the estimated (90)Y-microspheres activity/cc (MBq/cc) was calculated from the effective dose injected. Baseline VOI FDG PET SUVmean and max values and estimated MBq/cc values were related to treatment response using a lesion-based approach (% change in SUVmean ≥  50%) and a clinical dichotomous approach. Fifteen treatment sessions were analyzed (13 patients). Using the lesion-based approach (12 treatment sessions) 40 lesions responded and 37 did not. SUVmax and mean values proved significantly different between non-responding and responding lesions; 18.6 (SD 10.8) versus 13.5 (SD 8.4 ) for SUVmax (p = 0.02) and 11.4 (SD 3.8) versus 6.3 (SD 4.5) for SUVmean (p = 0.002). Using the clinical dichotomous approach (15 treatment sessions / 11 responding), 91 lesions were analyzed; 57 responded. VOI volumes and estimated (90)Y-loaded glass microspheres activity (MBq/cc) did not differ between responders and non responders; 24 cc (SD 27) versus 21 cc (SD 21 cc) (p = 0.4) and 1.95 MBq/cc (SD 1.1 MBq/cc) versus 1.90 MB/cc (SD 2.7 MBq/cc) (p = 0.92). On the contrary, SUVmax and mean values proved significantly different between responders and non-responders; 23.7 (SD 9.8) versus 9.4 (SD 3.8 ) for SUVmax (p = 0.0001) and 13.1 (SD 8.1) versus 4.9 (SD 1.4) for SUVmean. CONCLUSION These findings suggest that in patients presenting with high baseline SUVmax and mean values, the administration of higher activities or alternatively, other potentially more useful treatment options might be considered.

The use of uHear™ to screen for hearing loss in older patients with cancer as part of a comprehensive geriatric assessment

Abstract Objective: We previously validated uHear™ to screen for hearing loss in older patients with cancer without a known hearing loss, as part of a comprehensive geriatric assessment (CGA). In view of low specificity, we tested a new modified uHear™ scoring system as described by Handzel. Methods: Patients, aged ≥70 years, were evaluated by uHear™ and conventional audiometry, which is considered the gold standard, as part of a CGA. The pass or fail screening cut-off for uHear™ was defined as having ≥2 consecutive hearing grades starting from the moderate–severe threshold zone ranging from 0.5 to 2.0 kHz (modified Handzel-uHear™ scoring system). To accept the modified Handzel-uHear™ as screening tool, it was predefined that the combined sensitivity (S) and specificity (Sp) of the test (S + Sp/2) was at least 80% and that an actual combined (S + Sp)/2 of 90% would be found. Results: Ninety ears (45 subjects) were tested. Of those ears, 24.4% were identified as impaired by conventional audiometry. Modified Handzel-uHear™ identified 26.7% of tested ears as impaired. The combined (S + Sp)/2 of the modified Handzel-uHear™ was calculated as 77.5%, while in previous cohort, this was retrospectively calculated as 94.6%. A new uHear™ scoring system was proposed and tested in current and previous cohort. A (S + Sp)/2 of 80.2 and 78.8%, respectively, were obtained. Conclusion: uHear™ is a feasible tool for use within the CGA and shows promising results. However, further research is warranted to optimize the cut-off method before it could be routinely implemented within geriatric oncology.

Do refined consensus guidelines improve the uniformity of clinical target volume delineation for rectal cancer? Results of a national review project

In a previous national central review project, 74% of the rectal cancer clinical target volumes (CTVs) needed a modification. In a follow-up initiative, we evaluated whether the use of refined international consensus guidelines improves the uniformity of CTV delineation in clinical practice.

Quantitative p retreatment VOI analysis of liver metastases

UNLABELLED Using quantitive VOI analysis, the percentage (99m)Tc-MAA uptake and SUVmax and mean values of liver metastases obtained prior to SIRT were related to treatment response using both a lesion-based and clinical dichotomous approach. Based on the VOI % of (99m)Tc-MAA activity, the estimated (90)Y-microspheres activity/cc (MBq/cc) was calculated from the effective dose injected. Baseline VOI FDG PET SUVmean and max values and estimated MBq/cc values were related to treatment response using a lesion-based approach (% change in SUVmean ≥  50%) and a clinical dichotomous approach. Fifteen treatment sessions were analyzed (13 patients). Using the lesion-based approach (12 treatment sessions) 40 lesions responded and 37 did not. SUVmax and mean values proved significantly different between non-responding and responding lesions; 18.6 (SD 10.8) versus 13.5 (SD 8.4 ) for SUVmax (p = 0.02) and 11.4 (SD 3.8) versus 6.3 (SD 4.5) for SUVmean (p = 0.002). Using the clinical dichotomous approach (15 treatment sessions / 11 responding), 91 lesions were analyzed; 57 responded. VOI volumes and estimated (90)Y-loaded glass microspheres activity (MBq/cc) did not differ between responders and non responders; 24 cc (SD 27) versus 21 cc (SD 21 cc) (p = 0.4) and 1.95 MBq/cc (SD 1.1 MBq/cc) versus 1.90 MB/cc (SD 2.7 MBq/cc) (p = 0.92). On the contrary, SUVmax and mean values proved significantly different between responders and non-responders; 23.7 (SD 9.8) versus 9.4 (SD 3.8 ) for SUVmax (p = 0.0001) and 13.1 (SD 8.1) versus 4.9 (SD 1.4) for SUVmean. CONCLUSION These findings suggest that in patients presenting with high baseline SUVmax and mean values, the administration of higher activities or alternatively, other potentially more useful treatment options might be considered.

The distress thermometer predicts subjective, but not objective, cognitive complaints six months after treatment initiation in cancer patients

ABSTRACT Objectives: Research has indicated that cancer-related cognitive impairments (CRCI) may be influenced by psychosocial factors such as distress, worry and fatigue. Therefore, we aimed to validate the distress thermometer (DT) as a screening tool to detect CRCI six months post-treatment-initiation in a group of general cancer patients. Methods: Patients (≥18 years, n = 125) with a histologically confirmed diagnosis of a solid cancer or hematological malignancy, scheduled for a curative treatment, were evaluated at baseline (T0) and six months post-treatment-initiation (T1) for CRCI by a neuropsychological assessment, including patient-reported outcome measures (PROMs). Assessed cognitive domains included premorbid intelligence, attention, processing speed, flexibility, verbal and visual episodic memory and verbal fluency. PROMs entailed distress (DT, cut-off ≥4, range 0–10), anxiety and depression, fatigue (FACIT-fatigue scale) and subjective cognitive complaints. Results: At T0, 60.4% of patients showed a DT score of ≥4, whereas 50% met this criterion at T1. According to the definition of the International Cognition and Cancer Task Force, 25.5% and 28.3% of patients presented with a CRCI at T0 and T1, respectively. When evaluating the DT as a screening tool for CRCI at T1, data showed an inverse relationship between the DT and CRCI. ROC-curve analysis revealed an AUC <0.5. ROC-curve analyses evaluating the DT and FACIT-fatigue scale as screening tools for subjective cognitive complaints showed an AUC ± SE of, respectively, 0.642 ± 0.067 and 0.794 ± 0.057. Conclusions: The DT at T0 cannot be used to screen for objective CRCI at T1, but both the DT and FACIT-fatigue scale at T0 showed potential as screening tools for subjective cognitive complaints at T1.

SP-0333: Evaluation of radiotherapy utilisation in Belgium: patterns and possible causes of suboptimal use

Conclusion: The current clinical indications and trials for hypofractionation have the potential to reduce the evidencebased estimates of demand of radiotherapy sufficiently to be achievable with a modest increase of the current levels of equipment in England. While the presented calculations are for England as a whole, the Malthus program offers the facility to calculate the changes in modelled demand at a regional level within England, enabling a more precise calculation for treatment centres and their local catchment.

Quantitative p retreatment VOI analysis of liver metastases. (99m)Tc-MAA SPECT/CT and FDG PET/CT in relation with treatment response to SIRT.

UNLABELLED Using quantitive VOI analysis, the percentage (99m)Tc-MAA uptake and SUVmax and mean values of liver metastases obtained prior to SIRT were related to treatment response using both a lesion-based and clinical dichotomous approach. Based on the VOI % of (99m)Tc-MAA activity, the estimated (90)Y-microspheres activity/cc (MBq/cc) was calculated from the effective dose injected. Baseline VOI FDG PET SUVmean and max values and estimated MBq/cc values were related to treatment response using a lesion-based approach (% change in SUVmean ≥  50%) and a clinical dichotomous approach. Fifteen treatment sessions were analyzed (13 patients). Using the lesion-based approach (12 treatment sessions) 40 lesions responded and 37 did not. SUVmax and mean values proved significantly different between non-responding and responding lesions; 18.6 (SD 10.8) versus 13.5 (SD 8.4 ) for SUVmax (p = 0.02) and 11.4 (SD 3.8) versus 6.3 (SD 4.5) for SUVmean (p = 0.002). Using the clinical dichotomous approach (15 treatment sessions / 11 responding), 91 lesions were analyzed; 57 responded. VOI volumes and estimated (90)Y-loaded glass microspheres activity (MBq/cc) did not differ between responders and non responders; 24 cc (SD 27) versus 21 cc (SD 21 cc) (p = 0.4) and 1.95 MBq/cc (SD 1.1 MBq/cc) versus 1.90 MB/cc (SD 2.7 MBq/cc) (p = 0.92). On the contrary, SUVmax and mean values proved significantly different between responders and non-responders; 23.7 (SD 9.8) versus 9.4 (SD 3.8 ) for SUVmax (p = 0.0001) and 13.1 (SD 8.1) versus 4.9 (SD 1.4) for SUVmean. CONCLUSION These findings suggest that in patients presenting with high baseline SUVmax and mean values, the administration of higher activities or alternatively, other potentially more useful treatment options might be considered.