Response of bilateral Wilms tumor to chemotherapy suggests histologic subtype and guides treatment.

BACKGROUND: Patients with bilateral Wilms tumor initially receive neoadjuvant chemotherapy to shrink the tumors and increase the likelihood of successful nephron-sparing surgery. Biopsy of poorly responding tumors is often done to better understand therapy resistance. The purpose of this retrospective, single-institution study was to determine whether initial chemotherapy response is associated with tumor histology, potentially obviating the need for biopsy or change in chemotherapy. METHODS: Patients with synchronous bilateral Wilms tumors who underwent surgery at St Jude Children's Research Hospital from January 2000 to March 2022 were considered for this study. A mixed-effects logistic regression model was used to evaluate the likelihood of the tumor being stromal predominant, as predicted by tumor response to neoadjuvant chemotherapy. RESULTS: A total of 68 patients were eligible for this study. Tumors that increased in size had an odds ratio of 19.5 (95% confidence interval [CI] = 2.46 to 155.03) for being stromal predominant vs any other histologic subtype. Age at diagnosis was youngest in patients with stromal-predominant tumors, with a mean age of 18.8 (14.1) months compared with all other histologic subtypes (χ2 = 7.05, P = .07). The predictive value of a tumor growing combined with patient aged younger than 18 months for confirming stromal-predominant histology was 85.7% (95% CI = 57.18% to 93.5%). CONCLUSIONS: Tumors that increased in size during neoadjuvant chemotherapy were most frequently stromal-predominant bilateral Wilms tumor, especially in younger patients. Therefore, nephron-sparing surgery, rather than biopsy, or extension or intensification of neoadjuvant chemotherapy, should be considered for bilateral Wilms tumors that increase in volume during neoadjuvant chemotherapy, particularly in patients aged younger than 18 months.

Virtual Reality "exergames": A promising countermeasure to improve motivation and restorative effects during long duration spaceflight missions.

Long duration spaceflight missions will require novel exercise systems to protect astronaut crew from the detrimental effects of microgravity exposure. The SPRINT protocol is a novel and promising exercise prescription that combines aerobic and resistive training using a flywheel device, and it was successfully employed in a 70-day bed-rest study as well as onboard the International Space Station. Our team created a VR simulation to further augment the SPRINT protocol when using a flywheel ergometer training device (the Multi-Mode Exercise Device or M-MED). The simulation aspired to maximal realism in a virtual river setting while providing real-time biometric feedback on heart rate performance to subjects. In this pilot study, five healthy, male, physically-active subjects aged 35 ± 9.0 years old underwent 2 weeks of SPRINT protocol, either with or without the VR simulation. After a 1-month washout period, subjects returned for a subsequent 2 weeks in the opposite VR condition. We measured physiological and cognitive variables of stress, performance, and well-being. While physiological effects did not suggest much difference with the VR condition over 2 weeks, metrics of motivation, affect, and mood restoration showed detectable differences, or trended toward more positive outcomes than exercise without VR. These results provide evidence that a well-designed VR "exergaming" simulation with biometric feedback could be a beneficial addition to exercise prescriptions, especially if users are exposed to isolation and confinement.