Table 1.
CSF diagnostic biomarkers in the 3 cases
| IL-10 (pg/ml) | IL-10/IL-6 ratio | CXCL-13 (pg/ml) | MYD88 mutation analysisb | B-cell clonality assays | Cytology | Flow cytometry | |
|---|---|---|---|---|---|---|---|
| Case 1 | 34a | 0.48 | 10′826a | L265Pa | Monoclonal IGL gene rearrangementa | Neg (3x) | Neg (4x) |
| Case 2 | 52a | 7.5a | 3′053a | L265Pa | Monoclonal IGK gene rearrangementa | Neg (1x) | Neg (1x) |
| Case 3 | 68a | 16.2a | 239a | L265Pa | Not performed | Neg (1x) | Neg (1x) |
| Published cut-offs for PCNSL diagnosis | > 2.7–16.15 pg/ml (12) | > 0.72–1.6 (19–21) | > 80–90 pg/ml (9,10,13,14) | ||||
IL-10 Interleukin-10, IL-6 Interleukin-6, CXCL-13 Chemokine ligand 13, MYD88 Myeloid differentiation primary response 88, IGL Immunoglobulin light chain lambda, PCNSL Primary central nervous system lymphoma, Neg Negative
aValues/test results suggestive of PCNSL
bIdentification of the MYD88 hotspot mutation, c.794 T > C p.(Leu265Pro) – most commonly referred to as L265P – according to reference transcript NM_002468.4. According to other reference transcripts this same mutation may be referred to as c.755 T > C p.(Leu252Pro) (NM_002468.5, corresponding to the currently approved MANE transcript), or as c.818 T > C p.(Leu273Pro) (NM_001172567.1 or LRG_157t1)