Case report: Lumpy skin disease in an endangered wild banteng (Bos javanicus) and initiation of a vaccination campaign in domestic livestock in Cambodia

We describe a case of lumpy skin disease in an endangered banteng in Cambodia and the subsequent initiation of a vaccination campaign in domestic cattle to protect wild bovids from disease transmission at the wildlife-livestock interface. Lumpy skin disease virus (LSDV) was first detected in domestic cattle in Cambodia in June of 2021 and rapidly spread throughout the country. In September 2021, a banteng was seen in Phnom Tnout Phnom Pok wildlife sanctuary with signs of lumpy skin disease. Scab samples were collected and tested positive for LSDV. Monitoring using line transect surveys and camera traps in protected areas with critical banteng and gaur populations was initiated from December 2021-October 2022. A collaborative multisector vaccination campaign to vaccinate domestic livestock in and around priority protected areas with banteng and gaur was launched July 2022 and a total of 20,089 domestic cattle and water buffalo were vaccinated with LumpyvaxTM. No signs of LSDV in banteng or gaur in Cambodia have been observed since this initial case. This report documents the first case of lumpy skin disease in wildlife in Cambodia and proposes a potential intervention to mitigate the challenge of pathogen transmission at the domestic-wildlife interface. While vaccination can support local livestock-based economies and promote biodiversity conservation, it is only a component of an integrated solution and One Health approach to protect endangered species from threats at the wildlife-livestock interface.

P04.15 Radiomics features in prediction of pseudo-progression and response to hypofractionated stereotactic radiotherapy and anti-PDL1 Durvalumab combination in recurrent glioblastoma from STERIMGLI phase I trial

BACKGROUND

Due to the risk of pseudo-progression, evaluating the response of such combined treatment with anti-PDL1 immunotherapy and hypofractionated stereotactic radiotherapy (hFSRT) in patients with recurrent glioblastoma (GBM) is difficult even with iRANO criteria. We aim to analyze multi-modal MRI radiomic features in recurrent GBM patients included in the phase I STERIMGLI (NCT02866747) clinical trial.

MATERIAL AND METHODS

In phase I trial STERIMGLI, six patients received hFSRT 24 Gy in 3 fractions of 8 Gy prescribed to the 80% covering isodose in combination with Durvalumab IV 1500mg the same day following the third fraction of radiation then every 4 weeks for a maximum of 12 months. All patients underwent multi-modal MRI acquisitions. Contrast-enhancement on post-gadolinium T1 MRI (Gd-T1) and hyper-T2 signal on FLAIR MRI were manually segmented as volume-of-interest (VOIs) from baseline at week 0 (W0) and every eight weeks until weeks sixteen (W16). For patient 05, segmentation was performed until progression (W40). First order radiomics were extracted and normalized from these longitudinal VOIs in a total of 42 MRI: volume (in cm3), mean and median intensity, entropy, skewness and kurtosis were computed for each VOI. In total 504 (2 x 42 x 6) features were extracted.

RESULTS

Two patients underwent pseudoprogression (patients 04 and 05).

All patients but one (patient 05) presented an early relapse with an increase of FLAIR and Gd-T1 volumes and respective entropies from the first evaluation without decrease during follow up (until W16).

Patient 05 presented a Dose Limiting Toxicities and had the longest time to progression after Durvalumab and hFSRT. Contrary to the other patients, his FLAIR radiomics features presented a decrease of volume, intensity and entropy between W0 and W16 then, interestingly an increase between W24 and W40, date of progression. Moreover, patient 05 presented the lowest tumor volume and the lowest Gd-T1entropy. The intensity of the Gd-T1 followed the same trend as the hyper intense signal on the FLAIR in all patients, in particular for patient 05.

CONCLUSION

In our study, entropy and tumor volume for both FLAIR and Gd-T1, and FLAIR intensity seems to be the most interesting parameters to access the response of combined treatment. FLAIR signal may be more specific to the tumor microenvironment.

First order radiomics allowed us to follow tumor heterogeneity and identify the patient with the longest time to progression.

Examining Trajectories of Change for Prosperous Forest Landscapes in Cambodia

Tropical forest landscapes are undergoing rapid transition. Rural development aspirations are rising, and land use change is contributing to deforestation, degradation, and biodiversity loss, which threaten the future of tropical forests. Conservation initiatives must deal with complex social, political, and ecological decisions involving trade-offs between the extent of protected areas and quality of conservation. In Cambodia, smallholders and industrial economic land concessions drive deforestation and forest degradation. Rural economic benefits have not kept pace with development aspirations and smallholders are gradually expanding agriculture into protected forests. We examine the drivers and effects of rural forest landscape transitions in Cambodia to identify trade-offs between conservation and development. Using historical trends analysis and information gathered through key informant interviews, we describe how local communities perceive social and ecological changes, and examine the implications of local development aspirations for conservation. We explore three scenarios for the future of conservation in Cambodia, each with different conservation and community development outcomes. We contend that conservation efforts should focus on strengthening governance to meet social and environmental requirements for sustainable forest landscapes. We suggest potential entry points for governance improvements, including working with local decision-makers and fostering collaboration between stakeholders. There is a need for realistic priority setting in contested tropical forest landscapes. Prosperous rural economies are a necessary but not sufficient condition for conservation.

Effect of REDD+ projects on local livelihood assets in Keo Seima and Oddar Meanchey, Cambodia

Climate-change mitigation projects are expected to improve local livelihoods in targeted areas. Several REDD+ projects aimed at reducing emissions from deforestation and forest degradation, conserving and enhancing forest carbon stocks, and sustainably managing forests have been implemented in Cambodia but few studies have examined the effects on local livelihoods before and during project implementation. Our study applies a sustainable livelihood framework to assess the livelihood assets of local communities in the Oddar Meanchey and Keo Seima REDD+ project sites in Cambodia before and during project implementation. Five capital assets, namely natural, physical, human, financial, and social capital, are assessed and scored on a 1-to-5 Likert scale. Data analysis collected through 252 interviews in Oddar Meanchey and Keo Seima reveals a slight increase in livelihood assets in both sites from project validation to implementation. Generally, the mean scores for local livelihood assets increased from 2.81 ± 0.07 (±is followed by the standard error) and 2.66 ± 0.06 to 3.07 ± 0.09 and 3.06 ± 0.08 in Oddar Meanchey and Keo Seima, respectively. Nevertheless, natural capital assets sharply declined from 3.50 and 3.32 to 2.09 and 2.25, respectively. Respondents mainly blamed illegal logging for the decline, suggesting that strict patrolling and enforcement must be implemented. Furthermore, the scarcity of carbon-credit buyers and the projects’ inability to generate carbon-based revenues has led to dissatisfaction among local communities, inducing avoidable illegal activities in pursuit of short-term benefits. A financial mechanism to ensure sufficient and sustained financial support regardless of carbon-market volatility is urgently needed.

Identification of a candidate biomarker from perfusion MRI to anticipate glioblastoma progression after chemoradiation

OBJECTIVE

To identify relevant relative cerebral blood volume biomarkers from T2* dynamic-susceptibility contrast magnetic resonance imaging to anticipate glioblastoma progression after chemoradiation.

METHODS

Twenty-five patients from a prospective study with glioblastoma, primarily treated by chemoradiation, were included. According to the last follow-up MRI confirmed status, patients were divided into: relapse group (n = 13) and control group (n = 12). The time of last MR acquisition was t_end; MR acquisitions performed at t_end-2M, t_end-4M and t_end-6M (respectively 2, 4 and 6 months before t_end) were analyzed to extract relevant variations among eleven perfusion biomarkers (B). These variations were assessed through R(B), as the absolute value of the ratio between ∆B from t_end-4M to t_end-2M and ∆B from t_end-6M to t_end-4M. The optimal cut-off for R(B) was determined using receiver-operating-characteristic curve analysis.

RESULTS

The fraction of hypoperfused tumor volume (F_hP_g) was a relevant biomarker. A ratio R(F_hP_g) ≥ 0.61 would have been able to anticipate relapse at the next follow-up with a sensitivity/specificity/accuracy of 92.3 %/63.6 %/79.2 %. High R(F_hPg) (≥0.61) was associated with more relapse at t_end compared to low R(F_hPg) (75 % vs 12.5 %, p = 0.008).

CONCLUSION

Iterative analysis of F_hP_g from consecutive examinations could provide surrogate markers to predict progression at the next follow-up.

KEY POINTS

• Related rCBV biomarkers from DSC were assessed to anticipate GBM progression. • Biomarkers were assessed through their patterns of variation during the follow-up. • The fraction of hypoperfused tumour volume (F_hP _g ) seemed to be a relevant biomarker. • An innovative ratio R(F_hP _g ) could be an early surrogate marker of relapse. • A significant time gain could be achieved in the management of GBM patients.