Assessment of body composition in breast cancer patients: concordance between transverse computed tomography analysis at the fourth thoracic and third lumbar vertebrae.

Introduction: Specific body composition markers derived from L3 axial computed tomography (CT) images predict clinical cancer outcomes, including chemotherapy toxicity and survival. However, this method is only applicable to those undergoing lumbar (L3) CT scanning, which is not universally conducted in early breast cancer cases. This study aimed to evaluate CT analysis at T4 as a feasible alternative marker of body composition in breast cancer. Method: All patients participated in the Investigating Outcomes from Breast Cancer: Correlating Genetic, Immunological, and Nutritional (BeGIN) Predictors observational cohort study (REC reference number: 14/EE/1297). Staging chest-abdomen-pelvic CT scan images from 24 women diagnosed with early breast cancer at University Hospital Southampton were analysed. Adipose tissue, skeletal muscle, and muscle attenuation were measured from the transverse CT slices' cross-sectional area (CSA) at T4 and L3. Adipose tissue and skeletal muscle area measurements were adjusted for height. Spearman's rank correlation coefficient analysis was used to determine concordance between body composition measurements using CT analysis at L3 and T4 regions. Results: Derived estimates for total adipose tissue, subcutaneous adipose tissue, and intramuscular adipose tissue mass following adjustment for height were highly concordant when determined from CSAs of CT slices at T4 and L3 (Rs = 0.821, p < 0.001; Rs = 0.816, p < 0.001; and Rs = 0.830, p < 0.001). In this cohort, visceral adipose tissue (VAT) and skeletal muscle estimates following height adjustment were less concordant when measured by CT at T4 and L3 (Rs = 0.477, p = 0.039 and Rs = 0.578, p = 0.003). The assessment of muscle attenuation was also highly concordant when measured by CT at T4 and L3 (Rs = 0.840, p < 0.001). Discussion: These results suggest that the CT analysis at T4 and L3 provides highly concordant markers for total adipose, subcutaneous adipose, and intramuscular adipose estimation, but not VAT, in this breast cancer population. High concordance between T4 and L3 was also found when assessing skeletal muscle attenuation. Lower concordance was observed for the estimates of skeletal muscle area, potentially explained by differences in the quantity and proportions of axial and appendicular muscle between the thorax and abdomen. Future studies will determine the value of T4 metrics as predictive tools for clinical outcomes in breast cancer.

Unusual cause of gas complicating a biloma, postcholecystectomy.

A 50-year-old man presented to the emergency department with abdominal pain, vomiting and fever. He had been admitted 6 months ago with acute cholecystitis when he underwent endoscopic retrograde cholangiopancreatography (ERCP) to remove ductal gallstones. Elective cholecystectomy was performed 3 days prior to the current admission. CT demonstrated a fluid and gas containing collection in the gallbladder fossa, biliary gas and free intra-abdominal gas. ERCP revealed a retained common bile duct gallstone and leakage from the cystic duct remnant. We postulate that the gas within the collection originated from intrahepatic gas post-ERCP or from a gas forming organism. The free intra-abdominal gas originated from the collection rather than an intraoperative bowel injury. This complicated case highlights an unusual appearance of a common complication. It demonstrates the importance of discussion with the clinical team to ensure that an accurate diagnosis is made and the correct treatment is provided.

Gate-based high fidelity spin readout in a CMOS device.

The engineering of a compact qubit unit cell that embeds all quantum functionalities is mandatory for large-scale integration. In addition, these functionalities should present the lowest error rate possible to successfully implement quantum error correction protocols1. Electron spins in silicon quantum dots are particularly promising because of their high control fidelity2-5 and their potential compatibility with complementary metal-oxide-semiconductor industrial platforms6,7. However, an efficient and scalable spin readout scheme is still missing. Here we demonstrate a high fidelity and robust spin readout based on gate reflectometry in a complementary metal-oxide-semiconductor device that consists of a qubit dot and an ancillary dot coupled to an electron reservoir. This scalable method allows us to read out a spin in a single-shot manner with an average fidelity above 98% for a 0.5 ms integration time. To achieve such a fidelity, we combine radio-frequency gate reflectometry with a latched spin blockade mechanism that requires electron exchange between the ancillary dot and the reservoir. We show that the demonstrated high readout fidelity is fully preserved up to 0.5 K. This result holds particular relevance for the future cointegration of spin qubits and classical control electronics.

Community question.

THE BED manager scanned the whiteboard in the busy office of an acute psychiatric ward. 'What about this man, WL?' she asked. 'He's been in for nearly two weeks. Can he go on weekend leave?' The nurse in charge was sceptical, but an urgent admission was imminent, and there was no room. So WL was informed that he was ready for a trial period at home, and his bed was swiftly changed for the new arrival. Such is life in the inner-city psychiatric ward, where demand relentlessly exceeds supply.