Lines drawn.

Top Line: What are sources of variation in contouring mediastinal target volumes when treating stage III NSCLC?

The Study: ProCaLung is a Belgian project designed to evaluate the quality of mediastinal nodal target volume delineation for stage III NSCLC. Contouring was performed in a two step process of target identification and then delineation. A study by Peeters, et al. in 2016 established a useful algorithm for determining when to include mediastinal nodes in the GTV based on PET/CT and EBUS findings. The algorithm essentially recommends covering PET+ nodes regardless of EBUS results, and then relying on EBUS to determine whether or not to include PET- nodes. In their meta-analysis, EBUS of PET- nodes reduced the false negative rate by a relative ~80% for both enlarged and normal sized nodes. Without EBUS, enlarged nodes (short axis ≥1cm) are considered positive. The ESTRO-ACROP guidelines from 2018 were then used as a basis for mediastinal target volume delineation. These guidelines offer two methods for nodal CTV delineation. First, the entire nodal station including a 5-8mm expansion of the GTV can be delineated. Second, a geometric expansion of 5-8mm from the nodal GTV can be used with no additional coverage of the involved station. These guidelines also allow for elective inclusion of the ipsilateral hilum and stations adjacent to the involved stations. As you can imagine, the latter option may introduce significant variation in practice. In ProCaLung, ESTRO-ACROP-based CTV delineation was restricted to a 5mm GTV expansion (not the entire station) and no elective inclusion of adjacent stations. Quantitative and qualitative analysis of mediastinal GTV and CTV contours identified 3 persistent sources of variation. First was the inclusion of small neighboring nodes, i.e. those ≤5mm from a positive node. While the guidelines recommended including these in the CTV, 40% of participants included them in the GTV. The other two sources were frequent inclusion of the pericardium and superior aortic recess as well as adjacent, uninvolved blood vessels. The authors noted a lack of clear “crop-to” mediastinal structures in contouring guidelines as a reason why isotropic expansions often extend into the heart and vessels.

TBL: Clear contouring guidelines that specify how to handle common adjacent non-tumor structures and qualitative peer review are important ways to reduce variation in mediastinal target volume delineation | Charlier, Radiother Oncol 2021


  1. It Tears me Up Whenever we receive complaints from Clients About Their Experience With the Hackers They Met Before They Heard about us.
    These Days There Are alot of Hackers Online, You Just Have to Be Careful about who you meet for help, because many people now don't know who to ask for help anymore but there's actually a solution to that which I am giving you for free, Don't go out there seeking for Hackers Yourself, Because the probability of getting a Real Hacker Out there Is Very Slim . ❌❌ ❌ Most Of Them are actually not who they say they're, they are just here to Rip people Off, You Can Always Identify Them With Their False Advertisements and False Testimonies Trying To Lure you Into their Arms, And most of them use yahoomails, gmails and other cheaper email providers which could easily expose their vulnerabilities, Please Don’t Fall For Them�� Come To Think Of It, Why would a Legit Hacker Be using a gmail or a cheap email provider that exposes his vulnerabilities????⚠️⚠️⚠️
    Well, Our Purpose Here Is To Link You Up With Top Legit Hackers With Great Online Reputations and Impressive LinkedIn Profiles That’ll Blow Your Mind.

    ☑️ COMPOSITE FIRMWARE SECURITY SPECIALISTS is here to Provide you with The Best Hackers, So you can get saved from The Arms of the Fake Hackers❌❌.

    ☑️All our Specialists are well experienced in their various niches with Great Skills, Technical Hacking Strategies And Positive Online Reputations And Recommendations��
    They hail from a proven track record and have cracked even the toughest of barriers to intrude and capture all relevant data needed by our Clients.

    We have Digital Forensic Specialists, Certified Ethical Hackers, Software Engineers, Firmware Security Experts, Private investigators and more. Our Goal is to make your digital life secure, safe and hassle free by Linking you Up With these great Professionals such as JACK CABLE, ARNE SWINNEN, SEAN MELIA, DAWID CZAGAN, BEN SADEGHIPOUR And More. These Professionals are Well Reserved Professionals who are always ready to Handle your job with great energy and swift response so that your problems can be solved very quickly.
    All You Need to Do is to send us a mail and we’ll Assign any of these specialists to Handle your Job immediately.

    ☑️ Below Is A Full List Of Our Services:
    ▪️ CREDIT REPAIR. ��
    ▪️ PHONE HACKING & CLONING (giving you �� Unnoticeable access to everything Happening on the Target’s Phone)
    ▪️BITCOIN MINING ⛏ And lot More.

    ☑️ CONTACT:
    ��2021 © composite firmware specialists
    ��Want faster service? Contact us!
    ��All Rights Reserved ®️


Post a Comment

Popular Posts