More reasons to treat melanoma brain mets with checkpoint inhibitors!!!!

Tumor infiltrating lymphocytes and expression of programmed death ligand 1 (PD-L1) in melanoma brain metastases.
Berghoff, Ricken, Widhalm, et al.  Histopathology. 2014 Oct 14.

"Little is known about the inflammatory response to melanoma brain mets.  We investigated PD1, PD-L1, CD3, CD8, CD45RO, FOXP3, CD20, and BRAF V600E by immunohistochemistry in 43 brain met samples.  BRAF V600E positive = 62.8%.  CD3 positive TILs were evident in 76%. CD8 positive = 90%.  CD45RO positive = 74%.  PD1 positive = 62%.  FOXP3 positive = 48%. CD20 positive TILs were found in 44%.  PD-L1 expression was observed in 51%.  Of these, 40% presented with PD-L1 expression over 5% of tumor cells.  PD-L1 expression was associated with higher density of PD1, CD3, and FOXP3 positive TIL infiltration.  PD-L1 expression or PD1, CD3, CD8, or CD45RO positive TIL density did not correlate with BRAF status, previous systemic therapy or survival."

Conclusion:  "Melanoma brain mets show considerable lymphocytic infiltrates and expression of PD-L1 in the majority of investigated specimens, with high PD-L1 expression found predominately in regions of abundant inflammation.  Our data indicate that clinical studies should investigate the value of checkpoint inhibitors in patients with melanoma brain metastasis."

Amen and amen!  So let's go!!! - c