Jong, Pim A. de

Abstract Background and aims Carotid calcification features are readily quantifiable by CTA, yet their relationship with plaque vulnerability and rupture remains controversial. We investigated whether calcium score, volume, density, and residual (volume-normalized) calcium density are associated with carotid plaque vulnerability, symptomatic status, and recurrent ipsilateral ischemic stroke and transient ischemic attack (TIA). Methods Patients with recent TIA or ischemic stroke and ≥2mm carotid plaque with <70% stenosis underwent baseline CTA and MRI. Carotid calcifications were segmented on CTA (≥130 Hounsfield units), yielding calcium score, volume, and density. Volume-normalized residual calcium density was calculated as the standardized residuals from a log-transformed calcium density-volume model (Figure 1). Vulnerable plaque features (intraplaque hemorrhage, thin-or-ruptured fibrous cap, and lipid-rich necrotic core, and ulceration) were linked to calcium metrics. Associations between calcium metrics and recurrent ipsilateral TIA or ischemic stroke were assessed using Cox regression and adjusted for age, sex, stenosis. Results Among 193 patients (mean age 67.8±8.5 years, 144 (75%) men), 26 experienced ipsilateral ischemic stroke or TIA over median 5-year follow-up. Lower calcium density and residual calcium density were independently associated with vulnerable plaques (adjusted ORs: 0.40-0.60; Figure 2). Residual calcium density remained independently associated with symptomatic side (adjusted OR: 0.64, 95%CI: 0.47-0.88) and with recurrent TIA/stroke (adjusted HR: 0.53, 95%CI: 0.29-0.95). Calcium score, volume, and density were not independently associated with symptomatic side or recurrent events (Figure 3). Conclusions Residual calcium density is a robust, independent marker of carotid plaque vulnerability and ipsilateral ischemic stroke and TIA risk in patients with symptomatic carotid artery disease. Conflict of interest Juul Bierens: nothing to disclose; Daniel Bos: nothing to disclose; Paul J. Nederkoorn: nothing to disclose; Pim A. de Jong: nothing to disclose; Robert J. van Oostenbrugge: nothing to disclose; Luc J.M. Smits: nothing to disclose; Jae W. Song: nothing to disclose; Giuseppe Lanzino: nothing to disclose; M. Eline Kooi: nothing to disclose; Luca Saba: nothing to disclose. Figure 1 - belongs to Methods Figure 2 - belongs to Results Figure 3 - belongs to Conclusions

Abstract Background The association of body composition with checkpoint inhibitor outcomes in melanoma is a matter of ongoing debate. In this study, we aim to investigate body mass index (BMI) alongside computed tomography (CT)-derived body composition metrics in the largest cohort to date. Methods Patients treated with first-line anti-PD1 ± anti-CTLA4 for advanced melanoma were retrospectively identified from 11 melanoma centers in The Netherlands. From baseline CT scans, 5 body composition metrics were extracted: subcutaneous adipose tissue index, visceral adipose tissue index, skeletal muscle index, density, and gauge. These metrics were correlated in univariable and multivariable Cox proportional hazards analysis with progression-free survival, overall survival, and melanoma-specific survival (PFS, OS, and MSS). Results A total of 1471 eligible patients were included. Median PFS and OS were 9.1 and 38.1 months, respectively. Worse PFS was observed in underweight patients (multivariable hazard ratio [HR] = 1.86, 95% CI = 1.14 to 3.06). Furthermore, prolonged OS was observed in patients with higher skeletal muscle density (multivariable HR = 0.88, 95% CI = 0.81 to 0.97) and gauge (multivariable HR = 0.61, 95% CI = 0.82 to 0.998), whereas higher visceral adipose tissue index was associated with worse OS (multivariable HR = 1.12, 95% CI = 1.04 to 1.22). No association with survival outcomes was found for overweight, obesity, or subcutaneous adipose tissue. Conclusion Our findings suggest that underweight BMI is associated with worse PFS, whereas higher skeletal muscle density and lower visceral adipose tissue index were associated with improved OS. These associations were independent of known prognostic factors, including sex, age, performance status, and extent of disease. No significant association between higher BMI and survival outcomes was observed.

The prognostic value of CT-derived muscle quantity for overall survival (OS) in patients with non-small-cell lung cancer (NSCLC) is uncertain due to conflicting evidence. We hypothesize that increased muscle quantity is associated with better OS in patients with normal muscle radiodensity but not in patients with fatty degeneration of muscle tissue and low muscle radiodensity. We performed an observational cohort study in NSCLC patients treated with radiotherapy. A deep learning algorithm was used to measure muscle quantity as psoas muscle index (PMI) and psoas muscle radiodensity (PMD) on computed tomography. The potential interaction between PMI and PMD for OS was investigated using Cox proportional-hazards regression. Baseline adjustment variables were age, sex, histology, performance score and body mass index. We investigated non-linear effects of continuous variables and imputed missing values using multiple imputation. We included 2840 patients and observed 1975 deaths in 5903 patient years. The average age was 68.9 years (standard deviation 10.4, range 32 to 96) and 1692 patients (59.6%) were male. PMI was more positively associated with OS for higher values of PMD (hazard ratio for interaction 0.915; 95% confidence interval 0.861–0.972; p-value 0.004). We found evidence that high muscle quantity is associated with better OS when muscle radiodensity is higher, in a large cohort of NSCLC patients treated with radiotherapy. Future studies on the association between muscle status and OS should accommodate this interaction in their analysis for more accurate and more generalizable results.