Neoplasm of uncertain behavior of brain, infratentorial

This code signifies a brain tumor located in the infratentorial region (below the tentorium cerebelli) that has not yet been definitively classified as benign or malignant. The tumor exhibits characteristics that prevent a clear pathological diagnosis of either non-cancerous or cancerous behavior.

Use this code when pathology reports indicate a brain neoplasm of uncertain behavior, specifically located in the cerebellum, brainstem, or fourth ventricle. Supporting documentation should clearly state the infratentorial location and the pathologist's inability to definitively classify the tumor's biological potential.

• Distinguish carefully between "uncertain behavior" and "unspecified behavior"; this code requires documentation of specific features preventing definitive classification.
• Do not use this code if the pathology definitively identifies the tumor as benign (e.g., D33.1) or malignant (e.g., C71.6).
• Ensure the documentation explicitly states the infratentorial location; otherwise, a more general code for brain neoplasm of uncertain behavior might be appropriate.