Study of a Geometric Score to Identify the Increased Risk of Local Failure after SBRT for Locally Advanced Pancreatic Cancer (LAPC)

PURPOSE/OBJECTIVE(S)

A previous analysis on an institutional cohort of LAPC patients, treated with intensive induction chemotherapy followed by SBRT, proved that local failures (LFs) predominantly occurred within the RT field. This suggests a specific efficacy of a complete covering of the macroscopic (GTV) aggressive disease with high doses (i.e., simultaneous boost [SIB] doses). Still, this is often not feasible due to the proximity of extremely radiosensitive organs at risk (OARs), which forces the use of "Simultaneous Integrated Protection" (SIP), limiting the dose to safe values in a portion of the GTV. This analysis aimed to quantitatively assess the role of GTV size and incomplete GTV covering with SIB in increasing the risk of LF.

MATERIALS/METHODS

We included 51 consecutive LAPC pts treated with SBRT (Nov 2016 - Nov 2019): 30 Gy in 5 fractions to the tumor PTV, 50 Gy SIB to the region of vessel abutment/encasement, 25 Gy SIP to the overlap between tumor PTV, and the Planning OAR volumes. We used univariate/multivariable survival analysis (UVA/MVA, Cox regression, Kaplan-Meier Curves, Log-Rank test) to assess the association of LF with the GTV size and the amount of the GTV which the SIB did not cover. Specifically, we defined a set of incomplete GTV-covering levels: GTV75 (= yes if less than 75% of the GTV was included in the 50 Gy SIB isodose), GTV70, GTV50 and GTV30. Variables with p≤0.2 at UVA were included for MVA assessment. MVA models were considered relevant if their likelihood was significantly higher when compared to UVA.

RESULTS

With a median follow-up of 17 months (range 1.4-47) 12 pts experienced LF. The GTV size (p = 0.007, risk factor for LF, Hazard Ratio [HR] 1.04 for 1 cc increase in GTV size) and GTV70 (p = 0.2, risk factor, HR = 3.73 for GTV70 = yes) were selected at UVA and included in MVA. To build a simple decision tool, we dichotomized the GTV size as below/above 25 cc (selected from Youden Index on the ROC curve): HR = 9.3 if GTV>25 cc. We used dichotomized GTV size and GTV70 to build a 3-level Geometric Score for the prediction of the risk of LF: [Low Risk (LR)] if "GTV<25cc AND GTV70 = no"; [Intermediate Risk (IR)] if "GTV>25cc OR GTV70 = yes"; [High Risk (HiR)] if "GTV>25cc AND GTV70 = yes". Pts classified at HiR had a significantly higher probability of LF: HR = 6.9 (95% CI 1.5-32.9) compared to LR, and HR = 13.2 (95% CI 3.6-48.4) when compared to IR. 10/12 LFs are in the HiR group.

CONCLUSION

A large GTV size, coupled with an incomplete (<70%) covering of GTV from the SIB, highly increases the risk of LF: 62% actuarial probability in the HiR group vs 7% in the LR/IR groups. Full coverage of the GTV with SIB would be of clinical relevance for pts with large macroscopic tumors. The Geometric Score could be used to select pts that would effectively benefit from online tumor tracking (e.g., with an MRI-Linac), allowing a reduction of the SIP volume and a consequent decrease in the amount of GTV left uncovered by the SIB.

Prevalence and features of delirium in older patients admitted to rehabilitation facilities: a multicenter study

BACKGROUND

Delirium is thought to be common across various settings of care; however, still little research has been conducted in rehabilitation.

AIM

We investigated the prevalence of delirium, its features and motor subtypes in older patients admitted to rehabilitation facilities during the three editions of the "Delirium Day project".

METHODS

We conducted a cross-sectional study in which 1237 older patients (age ≥ 65 years old) admitted to 50 Italian rehabilitation wards during the three editions of the "Delirium Day project" (2015 to 2017) were included. Delirium was evaluated through the 4AT and its motor subtype with the Delirium Motor Subtype Scale.

RESULTS

Delirium was detected in 226 patients (18%), and the most recurrent motor subtype was mixed (37%), followed by hypoactive (26%), hyperactive (21%) and non-motor one (16%). In a multivariate Poisson regression model with robust variance, factors associated with delirium were: disability in basic (PR 1.48, 95%CI: 1.17-1.9, p value 0.001) and instrumental activities of daily living (PR 1.58, 95%CI: 1.08-2.32, p value 0.018), dementia (PR 2.10, 95%CI: 1.62-2.73, p value < 0.0001), typical antipsychotics (PR 1.47, 95%CI: 1.10-1.95, p value 0.008), antidepressants other than selective serotonin reuptake inhibitors (PR 1.3, 95%CI: 1.02-1.66, p value 0.035), and physical restraints (PR 2.37, 95%CI: 1.68-3.36, p value < 0.0001).

CONCLUSION

This multicenter study reports that 2 out 10 patients admitted to rehabilitations had delirium on the index day. Mixed delirium was the most prevalent subtype. Delirium was associated with unmodifiable (dementia, disability) and modifiable (physical restraints, medications) factors. Identification of these factors should prompt specific interventions aimed to prevent or mitigate delirium.

High-precision measurement of the W boson mass with the CDF II detector

The mass of the W boson, a mediator of the weak force between elementary particles, is tightly constrained by the symmetries of the standard model of particle physics. The Higgs boson was the last missing component of the model. After observation of the Higgs boson, a measurement of the W boson mass provides a stringent test of the model. We measure the W boson mass, M_W, using data corresponding to 8.8 inverse femtobarns of integrated luminosity collected in proton-antiproton collisions at a 1.96 tera-electron volt center-of-mass energy with the CDF II detector at the Fermilab Tevatron collider. A sample of approximately 4 million W boson candidates is used to obtain [Formula: see text], the precision of which exceeds that of all previous measurements combined (stat, statistical uncertainty; syst, systematic uncertainty; MeV, mega-electron volts; c, speed of light in a vacuum). This measurement is in significant tension with the standard model expectation.

The association between low skeletal muscle mass and delirium: results from the nationwide multi-centre Italian Delirium Day 2017

Introduction

Delirium and sarcopenia are common, although underdiagnosed, geriatric syndromes. Several pathological mechanisms can link delirium and low skeletal muscle mass, but few studies have investigated their association. We aimed to investigate (1) the association between delirium and low skeletal muscle mass and (2) the possible role of calf circumference mass in finding cases with delirium.

Methods

The analyses were conducted employing the cross-sectional “Delirium Day” initiative, on patient 65 years and older admitted to acute hospital medical wards, emergency departments, rehabilitation wards, nursing homes and hospices in Italy in 2017. Delirium was diagnosed as a 4 + score at the 4-AT scale. Low skeletal muscle mass was operationally defined as calf circumference ≤ 34 cm in males and ≤ 33 cm in females. Logistic regression models were used to investigate the association between low skeletal muscle mass and delirium. The discriminative ability of calf circumference was evaluated using non-parametric ROC analyses.

Results

A sample of 1675 patients was analyzed. In total, 73.6% of participants had low skeletal muscle mass and 24.1% exhibited delirium. Low skeletal muscle mass and delirium showed an independent association (OR: 1.50; 95% CI 1.09–2.08). In the subsample of patients without a diagnosis of dementia, the inclusion of calf circumference in a model based on age and sex significantly improved its discriminative accuracy [area under the curve (AUC) 0.69 vs 0.57, p < 0.001].

Discussion and conclusion

Low muscle mass is independently associated with delirium. In patients without a previous diagnosis of dementia, calf circumference may help to better identify those who develop delirium.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40520-021-01950-8.

Percutaneous puncture during PCNL: new perspective for the future with virtual imaging guidance

CONTEXT

Large and complex renal stones are usually treated with percutaneous nephrolithotomy (PCNL). One of the crucial steps in this procedure is the access to the collecting system with the percutaneous puncture and this maneuver leads to a risk of vascular and neighboring organs' injury. In the last years, the application of virtual image-guided surgery has gained wide diffusion even in this specific field.

OBJECTIVES

To provide a short overview of the most recent evidence on current applications of virtual imaging guidance for PCNL.

EVIDENCE ACQUISITION

A non-systematic review of the literature was performed. Medline, PubMed, the Cochrane Database and Embase were screened for studies regarding the use virtual imaging guidance for PCNL.

EVIDENCE SYNTHESIS

3D virtual navigation technology for PCNL was first used in urology with the purpose of surgical training and surgical planning; subsequently, the field of surgical navigation with different modalities (from cognitive to augmented reality or mixed reality) had been explored. Finally, anecdotal preliminary experiences explored the potential application of artificial intelligence guidance for percutaneous puncture.

CONCLUSION

Nowadays, many experiences proved the potential benefit of virtual guidance for surgical simulation and training. Focusing on surgery, this tool revealed to be useful both for surgical planning, allowed to achieve a better surgical performance, and for surgical navigation by using augmented reality and mixed reality systems aimed to assist the surgeon in real time during the intervention.