{"entity":{"id":"pet-adapted-therapy","kind":"technology","name":"PET-adapted (response-adapted) therapy","aka":[],"tldr":"Scan after two cycles of chemotherapy; if the tumour has gone dark, give less treatment, and if not, give more. Hodgkin lymphoma pioneered this.","summary":"Interim FDG-PET after cycle 2 (PET2) scored on the Deauville scale steers escalation or de-escalation: RATHL (omit bleomycin if PET2-negative, no loss of efficacy), HD18 (shorten escalated BEACOPP), HD16/HD17 and RAPID (omit radiotherapy in early stage if PET-negative, at a small PFS cost), and HD21/S1826 (PET-guided consolidation). Being extended to DLBCL and to ctDNA-adapted designs.","status":"standard-of-care","asOf":"2026-09-07","links":[{"label":"ClinicalTrials.gov NCT05675410: AHOD2131 (COG / NCTN)","url":"https://clinicaltrials.gov/study/NCT05675410"},{"label":"ClinicalTrials.gov NCT02661503: GHSG HD21","url":"https://clinicaltrials.gov/study/NCT02661503"},{"label":"Cheson et al., J Clin Oncol 2014: the Lugano classification for staging and response assessment in Hodgkin and non-Hodgkin lymphoma","url":"https://doi.org/10.1200/JCO.2013.54.8800"},{"label":"Barrington et al., J Clin Oncol 2014: the Imaging Working Group consensus on PET-CT in lymphoma and the five-point scale","url":"https://doi.org/10.1200/JCO.2013.53.5229"}],"tags":[],"related":[],"cancers":["hodgkin-lymphoma","dlbcl","non-hodgkin-lymphoma"],"sections":["imaging","chemotherapy"],"technologies":["fdg-pet","pet-ct"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["deauville-score"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Lymphoma: this is the disease group where response, rather than a molecular marker, directs treatment. The five-point scale compares the brightest site with the mediastinal blood pool and the liver, and the Lugano classification built it into formal response assessment and dropped the routine staging marrow biopsy for Hodgkin lymphoma and most diffuse large B-cell lymphoma (Cheson 2014, Barrington 2014). The ambiguity sits at score 3, which is read as adequate in de-escalation trials and inadequate in escalation trials."],"principle":"FDG-PET measures metabolic response early; Deauville ≥4 at PET2 predicts failure, allowing therapy to be tailored before completion.","strengths":["Spares most patients bleomycin, radiation or intensified chemotherapy","Identifies the minority who need escalation"],"limitations":["Interim PET has imperfect positive predictive value (many PET2-positive patients are cured anyway)","Omitting radiotherapy trades a few percent PFS for late-toxicity avoidance"],"since":2016},"route":"/technologies/pet-adapted-therapy/","neighbours":{"cancer":[{"id":"advanced-stage-classical-hodgkin-lymphoma","kind":"cancer","name":"Advanced-stage classical Hodgkin lymphoma (stage III to IV)","route":"/cancers/advanced-stage-classical-hodgkin-lymphoma/"},{"id":"dlbcl","kind":"cancer","name":"Diffuse large B-cell lymphoma","route":"/cancers/dlbcl/"},{"id":"early-stage-classical-hodgkin-lymphoma","kind":"cancer","name":"Early-stage classical Hodgkin lymphoma (stage I to II)","route":"/cancers/early-stage-classical-hodgkin-lymphoma/"},{"id":"hodgkin-lymphoma","kind":"cancer","name":"Hodgkin lymphoma","route":"/cancers/hodgkin-lymphoma/"},{"id":"non-hodgkin-lymphoma","kind":"cancer","name":"Non-Hodgkin lymphoma (all types)","route":"/cancers/non-hodgkin-lymphoma/"},{"id":"primary-mediastinal-b-cell-lymphoma","kind":"cancer","name":"Primary mediastinal (thymic) large B-cell lymphoma","route":"/cancers/primary-mediastinal-b-cell-lymphoma/"}],"section":[{"id":"chemotherapy","kind":"section","name":"Chemotherapy","route":"/fronts/chemotherapy/"},{"id":"imaging","kind":"section","name":"Imaging","route":"/fronts/imaging/"}],"technology":[{"id":"fdg-pet","kind":"technology","name":"FDG PET","route":"/technologies/fdg-pet/"},{"id":"pet-ct","kind":"technology","name":"PET/CT","route":"/technologies/pet-ct/"},{"id":"quantitative-imaging-biomarkers","kind":"technology","name":"Quantitative imaging biomarkers (RECIST, PERCIST, SUV, ADC)","route":"/technologies/quantitative-imaging-biomarkers/"}],"term":[{"id":"deauville-score","kind":"term","name":"Deauville five-point scale","route":"/terms/deauville-score/"},{"id":"deauville","kind":"term","name":"Deauville score and PET-adapted therapy","route":"/terms/deauville/"},{"id":"lymphoma-decision-beacopp-or-abvd","kind":"term","name":"Escalated chemotherapy or ABVD in advanced Hodgkin lymphoma: more cures, more late harm, and what the interim scan changed","route":"/terms/lymphoma-decision-beacopp-or-abvd/"},{"id":"lymphoma-tx-radiotherapy","kind":"term","name":"Radiotherapy in lymphoma: involved-site fields, 24 Gy, 4 Gy and total skin electron therapy","route":"/terms/lymphoma-tx-radiotherapy/"},{"id":"lymphoma-bio-hodgkin-microenvironment","kind":"term","name":"The Hodgkin microenvironment: when the cancer cell is the minority","route":"/terms/lymphoma-bio-hodgkin-microenvironment/"}],"trial":[{"id":"ahod2131","kind":"trial","name":"AHOD2131 (COG / NCTN)","route":"/trials/ahod2131/"},{"id":"hd21","kind":"trial","name":"GHSG HD21","route":"/trials/hd21/"},{"id":"ielsg37","kind":"trial","name":"IELSG37","route":"/trials/ielsg37/"},{"id":"rathl","kind":"trial","name":"RATHL","route":"/trials/rathl/"}],"pairing":[{"id":"bleomycin-omission-caution","kind":"pairing","name":"Caution: bleomycin lung toxicity, especially with brentuximab or G-CSF","route":"/pairings/bleomycin-omission-caution/"}],"idea":[{"id":"idea-chemo-free-hodgkin","kind":"idea","name":"Chemotherapy-free Hodgkin lymphoma: brentuximab + PD-1 in early stage","route":"/ideas/idea-chemo-free-hodgkin/"}]}}