C84.ZOther mature T/NK-cell lymphomas

C84.Z is the ICD-10-CM diagnosis code for other mature T/NK-cell lymphomas. It belongs to category C84 (mature T/NK-cell lymphomas), block C81-C96 (malignant neoplasms of lymphoid, hematopoietic and related tissue) and chapter 2 (neoplasms). It is a header code, so it can't be reported by itself; one of its 11 subcodes must be used instead.

Within C84, choose C84.Z (Other mature T/NK-cell lymphomas) only when documentation doesn't support a more specific option: mycosis fungoides (C84.0), Sezary disease (C84.1), peripheral T-cell lymphoma, not elsewhere classified (C84.4), Anaplastic large cell lymphoma, ALK-positive (C84.6), Anaplastic large cell lymphoma, ALK-negative (C84.7), unspecified (C84.9) and cutaneous T-cell lymphoma, unspecified (C84.A).

To report this condition, pick the subcode that matches the documentation: C84.Z0 (unspecified site), C84.Z1 (lymph nodes of head, face, and neck), C84.Z2 (intrathoracic lymph nodes), C84.Z3 (intra-abdominal lymph nodes), C84.Z4 (lymph nodes of axilla and upper limb), C84.Z5 (lymph nodes of inguinal region and lower limb), C84.Z6 (intrapelvic lymph nodes), C84.Z7 (spleen) and 3 more.

Don't report C84.Z together with the conditions in its Excludes1 note: angioimmunoblastic T-cell lymphoma (C86.50), blastic NK-cell lymphoma (C86.40), enteropathy-type T-cell lymphoma (C86.20), extranodal NK-cell lymphoma, nasal type (C86.00) and 4 more.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.