STEM fields.

Because the brainstem ain’t the parotid, it’s hard to be sure just how far is too far to push the brainstem dose when giving it all you got in the treatment of advanced nasopharyngeal carcinoma. That’s where this massive retrospective review is really helpful. It includes over 6000 patients who had IMRT (with standard doses and standard brainstem constraints) for nasopharyngeal carcinoma with post-treatment MRIs. Brainstem injury (BSI) was defined radiographically as either edematous or contrast enhancing lesions. Only 24 patients (0.4%) developed a BSI at a median of 15 months after treatment, and one-third of those developed symptoms. BSI resolved in just over half at roughly 12 months after development. Of the patients who died after having BSI, only one death was attributed to BSI with the rest succumbing to disease. The best dosimetric predictor of BSI was Dmax > 67.4 Gy, a good bit higher than the QUANTEC max of 64 Gy. TBL: Brainstem injury after radiation for nasopharyngeal carcinoma is rare, with Dmax of 67 Gy serving as a good dosimetric predictor. | Huang, Int J Radiat Oncol Biol Phys 2019