Peripheral T-cell lymphoma, NEC, intrapelvic lymph nodes

This code signifies a diagnosis of Peripheral T-cell lymphoma (PTCL) that does not fit into more specific PTCL subtypes, specifically affecting the lymph nodes located within the pelvic cavity. PTCLs are a diverse group of aggressive non-Hodgkin lymphomas arising from mature T-cells. This particular code indicates the primary or metastatic involvement of intrapelvic lymph nodes by this unspecified type of PTCL.

Use this code when documentation clearly states a diagnosis of "Peripheral T-cell lymphoma, not otherwise specified" or "PTCL, NOS," with confirmed involvement of intrapelvic lymph nodes. This code is appropriate when the specific subtype of PTCL (e.g., anaplastic large cell lymphoma, angioimmunoblastic T-cell lymphoma) has not been definitively identified or is not documented. Supporting documentation would include pathology reports confirming PTCL and imaging or surgical reports detailing intrapelvic lymph node involvement.

• Ensure the documentation specifies "intrapelvic" lymph nodes; otherwise, a more general site code may be appropriate.
• Avoid using this code if a more specific subtype of Peripheral T-cell lymphoma is documented (e.g., C84.0- for Mycosis fungoides, C84.1- for Sezary syndrome).
• Always sequence this code as a primary diagnosis when it represents the reason for the encounter or treatment.