Virtual Library

 x 
My Library Virtual Library FAQ

Start Your Search

D.K. Shelton



Author of

  • +

    MTE10 - RECIST and PERCIST Criteria for Response to Therapy (ID 54)

    • Event: WCLC 2013
    • Type: Meet the Expert (ticketed session)
    • Track: Imaging, Staging & Screening
    • Presentations: 1
    • +

      MTE10.1 - RECIST and PERCIST Criteria for Response to Therapy (ID 603)

      07:00 - 08:00  |  Author(s): D.K. Shelton

      • Abstract
      • Presentation
      • Slides

      Abstract
      RECIST AND PERCIST CRITERIA FOR RESPONSE TO THERAPY Background We need to accurately assess response to therapy for our patients with cancer, early in their treatment. Because modern treatments are costly (up to $10,000 per month), it is important to determine whether the current regimen is being effective and whether the patient will respond well with this treatment. If judged effective, stay the course. If current treatment is not being effective, then one could change management early, thus saving costs, avoiding unnecessary toxicities and improving quality of life. Anatomic Methods Tumor shrinkage has long been the standard for judging response to therapy since Moertel et al. published studies in 1976, comparing measurements of palpable tumors. WHO: In 1979 the World Health Organization (WHO) Handbook established imaging criteria for following solid tumors during therapy. Response was judged by tumor shrinkage. Complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD) were defined. Time to tumor progression (TTP), and progression free survival (PFS) defined when the disease recurred or progressed, including death in PFS. Measurable disease was defined with bidimensional tumor measurements, utilizing the product of longest diameter (LD) and short axis (SAX). RECIST 1.0: In 2000 the European Organization for Research and Treatment of Cancer (EORTC) and the National Cancer Institute (NCI) task force published imaging criteria as the Response Evaluation Criteria In Solid Tumors (RECIST) Guidelines. Measurable disease was defined unidimensionally, utilizing the LD. The LD of the target lesions was summed. CR: complete disappearance of all lesions. PR: ≥30% decrease of the sum. PD: ≥20% increase of the sum. For nontarget lesions, CR: complete resolution of all lesions; PD: unequivocal progression, or appearance of new lesions; SD: essentially stable, nontarget lesions such as pleural effusion. RECIST 1.1: Revised in 2009. Measurable disease defined unidimensionally, with the LD, except for lymph nodes in which the SAX is measured and must be ≥15mm at baseline. Normal lymph nodes defined as ≤10mm SAX. The SAX of the target lymph nodes is added to the sum of the LD of other target lesions. With conventional techniques (such as CXR or palpable lesions), target lesions need to be ≥20mm at baseline, or ≥10mm for spiral CT. CR: complete resolution. PR: ≥30% decrease of the sum. PD: ≥20% increase of the sum. For nontarget lesions, CR: complete disappearance, such as effusions or lymphangietic tumor. PD: “unequivocal” progression, or appearance of new lesions. PD can also be new “PET positive” lesions. Biomarkers We currently have several clinically accepted biomarkers for evaluating active tumors: serum thyroglobulin (TG) for thyroid cancer, prostate specific antigen (PSA) for prostate cancer, and CA-125 for ovarian cancer. With the advent of personalized medicine, other individual biomarkers, cell markers and genetic makers for a tumor are increasingly utilized and may require biopsy to evaluate evolving tumor mutations and chemo-resistance. New biomarkers include (HER2) for breast cancer, and KRAS gene mutations for epidermal growth factor receptor (EGFR) in colorectal cancer and lung cancer. PET-CT with FDG has also become an established imaging biomarker for hypermetabolic tumor activity. Functional Methods Functional methods for judging tumor response include dynamic contrast enhancement (DCE) with CT or MRI, MR spectroscopy (MRS), MR diffusion weighted imaging (DWI), ultrasound contrast enhancement, and optical coherence techniques. DCE is well accepted for GIST tumors and is being studied for lung cancer and breast cancer at UC Davis. Molecular Methods As early as 1990, gallium-67 was utilized with gamma cameras and then SPECT, for judging tumor response in lymphomas and Hodgkin’s disease, and to determine tumor activity if CT showed residual masses. In 2007, the Harmonization Criteria were established for judging tumor response with CT and PET-CT in malignant lymphomas and essentially replaced gallium. PET-CT with flourine-18 fluorodeoxyglucose (FDG) has become clinical standard-of-care in the staging and follow-up of many tumors, including lung cancer, esophageal cancer, head and neck cancers, brain tumors, lymphomas, GIST tumors (Choi criteria, 2007), colorectal cancer, melanoma, cervical and ovarian cancers. PET-CT is a quantitative technology but is often used with qualitative evaluation, comparing tumor uptake to background, liver or blood pool activity. Viewing the whole body MIP (Maximum Intensity Projection) images can often quickly determine whether the primary lesion and metastatic lesions have greatly increased or decreased in number or metabolic activity. However, quantitative techniques are more objective and likely more precise in judging response to therapy. Quantitative techniques include measuring various forms of Standard Uptake Value (SUV) and total glycolytic volume (TGV). The same acquisition principles of PET-CT with FDG are also being studied for other radiopharmaceuticals such as F-18-fluorothymidine (FLT) for DNA synthesis, F-18-fluoroethyltyrosine (FET) for amino acid metabolism, F-18-fluoromisonidazole for hypoxia imaging, and numerous other PET radiotracers. PERCIST: In 2009, Wahl et al. published a landmark article for PET-CT, “From RECIST to PERCIST: Evolving Considerations for PET Response Criteria in Solid Tumors”. PERCIST (Positron Emission tomography Response Criteria In Solid Tumors) is a set of recommendations to help make PET-CT even more quantitative and more precise. Current recommendations involve stringent quality control for equipment, software standardization, standard dosing, consistent timing from injection to acquisition, SUV peak rather than SUV max, SUL (SUV with lean body mass) and standardized ROI shape and size. Current recommendation is for a 1 cm[3], spherical ROI placed within the most hypermetabolic area of the tumor (SUV peak). Setting the required number of lesions and judging the summed response are still being evaluated. Conclusions RECIST 1.1 criteria and anatomic measurements will continue to play an important central role in clinical trials and for individual patients. PERCIST criteria are evolving and will slowly be introduced in carefully planned clinical trials. PET-CT with FDG has been proven to judge tumor response sooner than anatomic techniques alone, and it is thought that PERCIST criteria will help decrease the costs and duration of clinical trials, as well as improve the quality of life by decreasing prolonged exposures to ineffective treatments and associated toxicities.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.