As I've said many times, "Melanoma sucks great big green stinky hairy wizard balls!!!" (An expansion of the sentiment first expressed by dear Ruthie!) BUT...leptomeningeal disease sucks even more. Here is an article posted earlier this year with additional links within: Leptomeningeal disease and melanoma Now, there's this:
High-resolution MRI demonstrates that more than ninety percent of small intracranial melanoma metastases develop in close relationship to the leptomeninges. Lasocki, Khoo, Lau, et al. Neuro Oncol. 2019 Sep 9.
MRI brain examinations of melanoma patients treated at a specialist oncology centre from July 2015 to June 2017 were retrospectively reviewed. The MRI examination on which IMM were first visible was identified, utilising 1mm volumetric post-contrast imaging prior to local therapy. Individual metastases (up to 10 per patient) were assessed for the presence of leptomeningeal contact, as well as their number, size and morphology. Lesions greater than/= to 10mm in long axis were excluded, in order to examine early metastatic disease.
75 patients had evidence of IMM. 15 patients had only lesion(s) measuring greater than/= to10mm at diagnosis, leaving 60 patients. 192 individual metastases were examined (median 2 per patient, interquartile range 1-4), 174 (91%) demonstrating leptomeningeal contact. A nodular morphology was observed in 154 of 192 (82%), 32 (17%) were ovoid but elongated along the cortex, and 6 (3%) were linear. Only three patients (5%) also exhibited a 'classic' linear leptomeningeal disease appearance.
Most IMM measuring between 2 and 9mm in diameter are corticomeningeal nodules. These data raise the hypothesis that deeper parenchymal extension of IMM occurs secondarily. If the leptomeninges provide a preferential site for establishment of IMM, further investigation of the underlying biology of this phenomenon may provide opportunities for novel therapeutic strategies for patients with IMM.
For what it's worth. The more we can learn about how to deal with this most unfortunate of evolutions in melanoma, the better. And as always, still holding dear Rob and his precious Adriana in my heart. ~ c