Understanding Extranodal Extension in Head and Neck Cancer: New Imaging Guidelines Explained

Extranodal extension is an important prognostic factor in head and neck cancer. Imaging plays a crucial role in detecting extranodal extension. However, current guidelines often rely on clinical findings, which may overlook subtle cases.

A study published in The Lancet Oncology aimed to establish a consensus-based grading system for imaging-detected extranodal extension in head and neck cancer. This system seeks to enhance diagnostic accuracy and standardization. The proposed guidelines recommend specific criteria for identifying imaging-detected extranodal extension, which include:

• Indistinct or irregular nodal margin or border
• Extension into perinodal fat
• Extension into adjacent structures
• Conglomerate, matted, and coalescent nodes

Additionally, the guidelines stipulate that certain factors should not influence the assessment of imaging-detected extranodal extension. These factors include:

• Distance of invasion into perinodal fat
• Type or number of involved adjacent structures
• Specific number of nodes involved

In an interview with Targeted Oncology^TM, Christina Henson, MD, radiation oncologist at the University of Oklahoma, discusses how these proposed guidelines could change practice for physicians and the effects on patients.

Transcription:

0:05 | There's some discussion of potentially incorporating these grading criteria into the next iteration of the [National Comprehensive Cancer Network (NCCN)]. guidelines. So that would be great, because everyone pretty much uses the NCCN guidelines, and that would mean that everyone's using the same scoring system, and that going forward, we'll be able to really evaluate this grading system better, just because everyone will be using it in the same way. That's an important part of being able to validate a new tool, right? If it is being widely used and we can study it better. Also for clinical trials, going forward, it will be helpful to have this framework as well, just for better communication and clarity and standardization of things on clinical trials.

0:58 | As far as for how it will affect patients, the the biggest way we think this will affect patients is that with the increased use of transoral robotic surgery [TORS] for [human papillomavirus (HPV)]-related oropharyngeal cancer. We really try to avoid offering TORS to patients who have extranodal extension. But again, right now, we don't really have the tools to call those more subtle varieties of extranodal extension, so a lot of times, those patients will go to surgery, then they're found to have extranodal extension after the fact on pathology, meaning that then they have to get chemo and radiation after surgery, whereas they probably just should have been treated with chemoradiation upfront and avoided surgery. So now they've been treated with 3 different modalities with 3 different sets of toxicities. So that'll be the biggest thing: we'll be more appropriately selecting the right treatment for the right patient based on suspicion for extranodal extension prior to pursuing a surgical route.