Malignant neoplasm of anterior mediastinum

This code signifies the presence of a cancerous tumor originating in the anterior compartment of the mediastinum, the space in the chest between the lungs. This region typically contains the thymus gland, lymph nodes, and connective tissue, and primary malignancies here often include thymomas, lymphomas, and germ cell tumors.

Use this code when documentation confirms a primary malignant neoplasm located specifically within the anterior mediastinal compartment. This diagnosis is typically established through biopsy and imaging studies such as CT or MRI. It is appropriate for both initial diagnosis and subsequent encounters for active treatment of the malignancy.

• Differentiate from secondary or metastatic mediastinal involvement, which would require a different code.
• Ensure the documentation specifies "anterior" mediastinum; other mediastinal compartments have distinct codes.
• Always sequence this code as the primary diagnosis when it is the reason for the encounter, unless a complication of the malignancy is being treated.