This study indicates that flow cytometry can be used to examine the tumor microenvironment in HL and that percentage of HLA-DR/CD38 copositive lymphocytes may be a biomarker for relapse and refractoriness in pediatric HL.

IMPORTANCE Pediatric acute myeloid leukemia (AML) requires multiple courses of intensive chemotherapy that result in neutropenia, with significant risk for infectious complications.Supportive care guidelines recommend hospitalization until neutrophil recovery. However, there are little data to support inpatient over outpatient management. OBJECTIVETo evaluate outpatient vs inpatient neutropenia management for pediatric AML. DESIGN, SETTING, AND PARTICIPANTSThis cohort study used qualitative and quantitative methods to compare medical outcomes, patient health-related quality of life (HRQOL), and patient and family perceptions between outpatient and inpatient neutropenia management. The study included patients from 17 US pediatric hospitals with frontline chemotherapy start dates ranging from January 2011 to July 2019, although the specific date ranges differed for the individual analyses by design and relative timing. Data were analyzed from August 2019 to February 2020. EXPOSURES Discharge to outpatient vs inpatient neutropenia management. MAIN OUTCOMES AND MEASURESThe primary outcomes of interest were course-specific bacteremia incidence, times to next course, and patient HRQOL. Course-specific mortality was a secondary medical outcome. RESULTSPrimary quantitative analyses included 554 patients (272 [49.1%] girls and 282 [50.9%] boys; mean [SD] age, 8.2 [6.1] years). Bacteremia incidence was not significantly different during outpatient vs inpatient management (67 courses [23.8%] vs 265 courses [29.0%]; adjusted rate ratio, 0.73; 95% CI, 0.56 to 1.06; P = .08). Outpatient management was not associated with delays to the next course compared with inpatient management (mean [SD] 30.7 [12.2] days vs 32.8 [9.7]days; adjusted mean difference, −2.2; 95% CI, −4.1 to −0.2, P = .03). Mortality during intensification II was higher for patients who received outpatient management compared with those who received inpatient management (3 patients [5.4%] vs 1 patient [0.5%]; P = .03), but comparable with inpatient management at other courses (eg, 0 patients vs 5 patients [1.3%] during induction I; P = .59). Among 97 patients evaluated for HRQOL, outcomes did not differ between outpatient and inpatient management (mean [SD] Pediatric Quality of Life Inventory total score, 70.1 [18.9] vs 68.7

No abstract