{"entity":{"id":"paper-lee-ctdna-adjuvant-benefit-localized-pancreatic-ann-oncol-2019","kind":"paper","name":"Circulating tumor DNA as a potential marker of adjuvant chemotherapy benefit following surgery for localized pancreatic cancer","aka":[],"tldr":"In an Australian study of patients having surgery for pancreatic cancer, everyone whose blood still held tumour DNA afterwards relapsed, including those who went on to have chemotherapy, which argues for testing whether such patients need more treatment.","summary":"Patients considered resectable were enrolled, with pre- and post-operative samples analysed by PCR-based SafeSeqS assays for KRAS codon 12, 13 and 61 mutations in the primary tumour and in plasma; management followed standard care blinded to results. Of 112 consented, 81 (72%) were resected; KRAS mutations were identified in 38 of 42 available tumours (91%). ctDNA was detected in 23 of 37 preoperative (62%) and 13 of 35 postoperative (37%) plasma samples. At a median 38.4 months, preoperative ctDNA predicted inferior recurrence-free (hazard ratio 4.1) and overall survival (4.1); postoperative detection predicted inferior recurrence-free (5.4) and overall survival (4.0). Recurrence occurred in 13 of 13 patients with detectable postoperative ctDNA, including 7 who received gemcitabine-based adjuvant chemotherapy.","asOf":"2026-09-24","links":[{"label":"Lee et al., Ann Oncol 2019: ctDNA before and after resection in 42 patients (Australian cohort)","url":"https://doi.org/10.1093/annonc/mdz200"},{"label":"PubMed","url":"https://pubmed.ncbi.nlm.nih.gov/31250894/"}],"tags":[],"related":["ctdna-mrd-positive"],"cancers":["pancreatic","resectable-pdac"],"sections":[],"technologies":["liquid-biopsy","mrd-testing"],"targets":["kras"],"drugs":["gemcitabine"],"companies":[],"institutions":[],"pathways":[],"terms":["ctdna","mrd"],"trials":[],"people":["jeanne-tie"],"bottlenecks":[],"keyPapers":[],"journals":["annals-of-oncology"],"dependsOn":[],"notes":[],"journal":"Annals of Oncology","year":2019,"doi":"10.1093/annonc/mdz200","pmid":"31250894","authors":"Lee B, Lipton L, Cohen J, et al.","paperType":"observational","findings":["Preoperative ctDNA in 62%, postoperative in 37%.","All 13 patients with postoperative ctDNA recurred, including 7 given adjuvant gemcitabine.","Hazard ratios 4.1 preoperative and 5.4 postoperative for recurrence."],"whatItMeans":"Postoperative ctDNA marks a group that current adjuvant chemotherapy does not cure, the rationale for ctDNA-guided intensification trials.","caveats":["Feasibility was poor: many patients did not proceed to resection or complete sampling.","KRAS codon-restricted assay and gemcitabine-era adjuvant therapy."],"changedPractice":false,"participants":112},"route":"/key-papers/paper-lee-ctdna-adjuvant-benefit-localized-pancreatic-ann-oncol-2019/","neighbours":{"biomarker":[{"id":"ctdna-mrd-positive","kind":"biomarker","name":"ctDNA MRD positivity (molecular residual disease after curative treatment)","route":"/biomarkers/ctdna-mrd-positive/"}],"cancer":[{"id":"pancreatic","kind":"cancer","name":"Pancreatic ductal adenocarcinoma","route":"/cancers/pancreatic/"},{"id":"resectable-pdac","kind":"cancer","name":"Resectable pancreatic ductal adenocarcinoma","route":"/cancers/resectable-pdac/"}],"technology":[{"id":"liquid-biopsy","kind":"technology","name":"Liquid biopsy (ctDNA)","route":"/technologies/liquid-biopsy/"},{"id":"mrd-testing","kind":"technology","name":"MRD / molecular residual disease testing","route":"/technologies/mrd-testing/"}],"target":[{"id":"kras","kind":"target","name":"KRAS","route":"/targets/kras/"}],"drug":[{"id":"gemcitabine","kind":"drug","name":"Gemcitabine","route":"/drugs/gemcitabine/"},{"id":"signatera","kind":"drug","name":"Signatera","route":"/drugs/signatera/"}],"term":[{"id":"ctdna","kind":"term","name":"Circulating tumour DNA (ctDNA)","route":"/terms/ctdna/"},{"id":"mrd","kind":"term","name":"Minimal / molecular residual disease (MRD)","route":"/terms/mrd/"}],"person":[{"id":"jeanne-tie","kind":"person","name":"Jeanne Tie","route":"/people/jeanne-tie/"}],"journal":[{"id":"annals-of-oncology","kind":"journal","name":"Annals of Oncology","route":"/journals/annals-of-oncology/"}]}}