Skip to content

AACR Annual Meeting 2026

April 17–22, 2026 · San Diego · 2418 items

After the meeting★★

MRD / ctDNA / DTP: from detection to treatment decisions

90 people · 90 posts5 topics

Start here

After surgery or drugs, can you still find tumor DNA in the blood? That is MRD / ctDNA. It used to mean “is anything left.” This meeting put it in a plenary: people who clear it have ~70% pathologic complete response; people who do not, ~0%. The test is becoming a gate on whether to keep treating.

Harder still: some cells neither die nor grow fast — drug-tolerant persisters. They change identity and bank mutations. “Is there tumor DNA in the blood” and “what state are the surviving cells in” are different questions.

Tumor-informed assays sequence the primary, then chase that mutation set in plasma, down below 1 in 10⁴. Tie’s plenary nailed the next post at 1 in 10⁶. CheckMate 77T used this path: 75% clearance on nivolumab versus 46% on placebo.

Hata rewrote DTPs from “waiting to grow” into cells that actively remodel transcriptome and epigenome, bank resistance mutations via APOBEC3A, and enter a high-plasticity state. Marine’s ORIGAMI writes melanoma as a MEL → transitory → MES state machine. A mutation catalogue is no longer enough; cell identity is.

Analysis

MRD this year moved from “is the assay sensitive enough” to “do we change treatment on the back of it.” Payers have started covering tumor-informed MRD, so the sensitivity race has a commercial door. Regulators have not yet accepted ctDNA clearance as a formal surrogate.

Nivolumab, pembrolizumab and durvalumab sit in this direction not as new drugs, but because perioperative IO trials wrote ctDNA into the stratification. The drugs live under immunotherapy; the use lives here.

Still open
  • Whether regulators will write ctDNA clearance as a surrogate endpoint.
  • Once MRD is positive, whether intensification should be chemo, an ADC, or immunotherapy.
  • Whether DTP / high-plasticity states have an intervention that can enter the clinic.
Key readout

CheckMate 77T · ctDNA clearance 75% vs 46%; clearers ~70% pCR, non-clearers ~0%Perioperative NSCLC · nivo

Records

Drug / trialReadoutSetting
CheckMate 77Tnivolumab#LIQUIDBIOPSY#NSCLCctDNA clearance 75% vs 46%; clearers ~70% pCR, non-clearers ~0%Perioperative NSCLC · nivo
Predicta#LIQUIDBIOPSIES#LIQUIDBIOPSYClaimed sensitivity 1 in 10⁶WGS ultrasensitive ctDNA
NSABP-B-59#BREASTCANCER#LIQUIDBIOPSYTumor-informed WES predicted non-pCR and distant recurrencePost-neoadjuvant TNBC · also under breast

Floor

Apr 23Thu
Apr 22Wed
Apr 21Tue
Apr 20Mon
Apr 19Sun
  4. 2 more on this topicnivolumab · 25
Apr 18Sat

Other directions

CBACBA Frontier Insights (CFI)Chinese Biopharmaceutical Association (CBA)www.cba-usa.org