Mediastinal (thymic) large B-cell lymphoma, intrapelv nodes

This code identifies a specific type of aggressive non-Hodgkin lymphoma originating from B-lymphocytes, characterized by its primary mediastinal (thymic) presentation but with metastatic involvement of intrapelvic lymph nodes. It signifies a disseminated stage of this particular large B-cell lymphoma.

Use this code when documentation confirms a diagnosis of mediastinal (thymic) large B-cell lymphoma with confirmed involvement of lymph nodes within the pelvic region. This typically follows biopsy and pathological confirmation of the lymphoma subtype and imaging studies (e.g., PET/CT) demonstrating intrapelvic lymphadenopathy.

• Ensure documentation explicitly states "mediastinal (thymic)" as the primary site and "intrapelvic lymph nodes" as the site of metastasis.
• Do not confuse with other types of large B-cell lymphoma or other lymphomas affecting the mediastinum or pelvis.
• Always sequence this code as the primary diagnosis when it is the reason for the encounter, unless another condition is clearly the principal diagnosis.