Top Line: Do isolated tumor cells in lymph nodes increase the risk of otherwise low risk endometrial cancer?
The Study: The finding of isolated tumor cells (ITCs, ≤0.2 mm or ≤200 cells) in regional lymph nodes of otherwise low-risk endometrial cancer patients has unclear prognostic significance, and it currently doesn't change management. This NCDB study identified 271 patients with ITCs and 43,289 node-negative patients, all with low-risk disease (grade 1–2 endometrioid, stage IA, no LVSI) treated with surgery alone (no VBT, chemo, or EBRT). At a median follow-up of roughly 3 years, 4-year OS was 89.5% for ITCs versus 96.3% for node-negative (HR 3.15, 95% CI 2.04–4.87), a gap that persisted across subgroups including grade 1 histology and tumors ≤4 cm. That HR looks alarming, but important caveats temper the enthusiasm for changing practice. Cause of death wasn't available (so we don't know how many of these were cancer-related), molecular classification was absent, depth of myometrial invasion beyond “inner half” wasn't captured, and the ITC cohort was small enough that the confidence intervals in several subgroups were broad. Still, a 4-year OS under 90% is hard to ignore in a population we routinely reassure needs no further treatment. Whether ITCs should prompt consideration of adjuvant therapy (and if so, what kind) remains unanswered.
TBL: In this NCDB study, the presence of isolated tumor cells in regional lymph nodes was associated with worse overall survival among patients with low risk endometrial cancer. | Matsuo, JAMA Oncol 2026
The Study: The finding of isolated tumor cells (ITCs, ≤0.2 mm or ≤200 cells) in regional lymph nodes of otherwise low-risk endometrial cancer patients has unclear prognostic significance, and it currently doesn't change management. This NCDB study identified 271 patients with ITCs and 43,289 node-negative patients, all with low-risk disease (grade 1–2 endometrioid, stage IA, no LVSI) treated with surgery alone (no VBT, chemo, or EBRT). At a median follow-up of roughly 3 years, 4-year OS was 89.5% for ITCs versus 96.3% for node-negative (HR 3.15, 95% CI 2.04–4.87), a gap that persisted across subgroups including grade 1 histology and tumors ≤4 cm. That HR looks alarming, but important caveats temper the enthusiasm for changing practice. Cause of death wasn't available (so we don't know how many of these were cancer-related), molecular classification was absent, depth of myometrial invasion beyond “inner half” wasn't captured, and the ITC cohort was small enough that the confidence intervals in several subgroups were broad. Still, a 4-year OS under 90% is hard to ignore in a population we routinely reassure needs no further treatment. Whether ITCs should prompt consideration of adjuvant therapy (and if so, what kind) remains unanswered.
TBL: In this NCDB study, the presence of isolated tumor cells in regional lymph nodes was associated with worse overall survival among patients with low risk endometrial cancer. | Matsuo, JAMA Oncol 2026