Increasingly, national accrediting bodies and professional societies for musculoskeletal oncology recognize the need for more standardized training. This study elucidates recent trends in reported case volume during Accreditation Council for Graduate Medical Education (ACGME)-accredited musculoskeletal oncology fellowship training relative to case minimum requirements. We conducted a retrospective cross-sectional analysis of fellows at ACGME-accredited musculoskeletal oncology fellowships (2017 to 2022). Percentiles in reported case volumes were calculated across ACGME-defined case categories and temporal changes assessed by linear regression. Variability between the highest (90th percentile) and lowest (10th percentile) deciles was calculated as fold differences. Sensitivity analyses were conducted to estimate the number of fellows not meeting ACGME-defined case minimum requirements. Case logs from 95 musculoskeletal oncology fellows were analyzed. From 2017 to 2022, total relevant oncology procedures increased from 191 ± 49 to 228 ± 73 (P = 0.066). Pediatric oncology accounted for a minority of cases (range, 6 to 8%). A mean of 222 total relevant oncology procedures were reported. Most were in management of metastatic disease (21%), soft-tissue resection/reconstruction (20%), and limb salvage (13%). Variability in total relevant oncology procedures was 2.6 and greatest in spine/pelvis (4.6), pediatric oncologic cases (4.4), and surgical management of complications (4.4). No clear trends were observed in case volume variability over the study period (P > 0.05). Analysis of case volume percentiles identified at least 30% of musculoskeletal oncology fellows not achieving minimum requirements for pediatric oncologic cases (n = 29 fellows) and 10% of fellows not achieving minimum requirements for total relevant oncology procedures (n = 10 fellows). Results from this study may help future musculoskeletal oncology fellows and faculty identify potential areas to increase case exposure and reduce variability during fellowship training. More investigation is needed to determine evidence-based case minimum requirements including surgical learning curves and other competency-based assessment tools in musculoskeletal oncology.