It is possible that Ag (or other) T-lymphoid stimulation within a certain context, in addition to inducing expression of ALCL-hallmark activation markers such as CD30, perforin and Granzyme B (ref. 3), and initial TCR signalling, may in some way subsequently trigger TCR silencing and unopposed ALK signalling. The gene discussed is PRF1; the disease is anaplastic large cell lymphoma.