ICD-10-CM 2027
ICD-10 code for Lennert's lymphoma
From the official ICD-10-CM alphabetic index entry “Lymphoma (of) (malignant) › Lennert's”. Page updated September 29, 2026.
About coding Lennert's lymphoma
The ICD-10-CM code for Lennert's lymphoma is C84.4 (Peripheral T-cell lymphoma, not elsewhere classified).
Within C84 (mature T/NK-cell lymphomas), C84.4 is specifically for peripheral T-cell lymphoma, not elsewhere classified. Related codes cover mycosis fungoides (C84.0), Sezary disease (C84.1), Anaplastic large cell lymphoma, ALK-positive (C84.6), Anaplastic large cell lymphoma, ALK-negative (C84.7), unspecified (C84.9), cutaneous T-cell lymphoma, unspecified (C84.A) and other mature T/NK-cell lymphomas (C84.Z).
To report this condition, pick the subcode that matches the documentation: C84.40 (unspecified site), C84.41 (lymph nodes of head, face, and neck), C84.42 (intrathoracic lymph nodes), C84.43 (intra-abdominal lymph nodes), C84.44 (lymph nodes of axilla and upper limb), C84.45 (lymph nodes of inguinal region and lower limb), C84.46 (intrapelvic lymph nodes), C84.47 (spleen) and 3 more.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015, and changed in FY2023 (title revised).