Serum TCLlnc1 was significantly higher in PTCL patients (ALK+ALCL, 0.651 ± 0.134, P < 0.0001, ALK−ALCL, 3.940 ± 1.625, P < 0.0001, AITL, 1.879 ± 0.335, P < 0.0001, and PTCL-NOS, 2.986 ± 0.457, P < 0.0001) than in HV (0.076 ± 0.030), no significant difference was observed between RH and HV (P = 0.5288, Fig. 2C). Here, ALK is linked to anaplastic large cell lymphoma.