Malignant neoplasm of overlapping sites of brain

This code signifies a primary cancerous tumor that spans across or involves multiple contiguous anatomical sub-sites within the brain, making it impossible to assign to a single, specific brain region. It indicates a single malignant process affecting more than one distinct area of the brain.

This code is appropriate when documentation specifies a primary brain malignancy that has spread across or originated in overlapping boundaries of different brain lobes or structures (e.g., frontal and temporal lobes, or cerebrum and cerebellum). Use when the physician explicitly states "overlapping sites" or describes a tumor that cannot be localized to a single, defined brain region.

• Do not use this code if the tumor's primary site can be clearly identified within a single brain region (e.g., C71.0 for cerebrum).
• Ensure the documentation explicitly supports the "overlapping sites" nature of the malignancy, rather than metastatic disease or multiple distinct primary tumors.
• Always sequence this code as the primary diagnosis when it represents the reason for the encounter, followed by any associated neurological deficits or complications.