Slim fit.

On the other end of the spectrum, it’s a common struggle to find the right balance of acceptable toxicity while still offering definitive management of a large, centrally-located, locally-advanced non-small cell lung cancer (NSCLC). There’s a plethora of data demanding the tumor receive a high threshold of radiation. But then heart, lung, esophagus constraints, oh my. This is precisely the dilemma of this month’s Gray Zone accompanied by three expert opinions [1, 2, 3]. Two suggest on, assuming IMRT and motion management with daily image guidance, forgoing the CTV margin altogether for a simple 5 mm GTV to PTV margin and even then prescribing full dose (typically 60Gy) only to GTV with smaller dose (something like 50 Gy) to PTV. A third focuses more on the option for induction therapy, remembering response rates to immune checkpoint inhibition and EGFR-targeted therapies are much higher than plain ol’ systemic therapy. | Tsao / Chang / Loo / Lang, Int J Radiat Oncol Biol Phys 2021