Use This Guide to Locate MSCH Code
Question: What is the most accurate ICD-10-CM code for mucosal Schwann cell hamartoma (MSCH), listed in the pathology report under a sigmoid colon biopsy? AAPC Forum Participant Answer: Because an MSCH is a rare and recently recognized condition, it does not currently have a dedicated ICD-10-CM code. However, if you examine the condition’s etiology, it is possible to come up with several codes that you can then use to document the condition. First, according to the National Library of Medicine, a harmartoma is “mostly a benign mass of disorganized tissue native to a particular anatomical location.” This automatically directs you to assign a benign neoplasm code from the D10.- (Benign neoplasm of mouth and pharynx) through D36.- (Benign neoplasm of other and unspecified sites) range. Exactly which code from that range you will assign, however, will depend on whether your provider classifies the condition by its pathology or location. For MSCH classified by pathology, you would look to codes that reflect the Schwann cell composition of the harmartoma. The cells are S100 positive, found in peripheral nerve-sheath tumors; this would lead to an ICD-10-CM code of D36.10 (Benign neoplasm of peripheral nerves and autonomic nervous system, unspecified). You would choose the unspecified code because the MSCH location in the sigmoid colon is not one of the locations specified by the other D36.1- (Benign neoplasm of peripheral nerves and autonomic nervous system) codes. As for location, MSCHs are usually found in the colon or rectum, especially the distal colon, during routine screening colonoscopies. This would then lead to assigning a diagnosis code from the D12.- (Benign neoplasm of colon, rectum, anus and anal canal) category, most likely one of the following: Given that the pathology report you mention notes the MSCH was found in a sigmoid colon biopsy, and assuming the report gives no other relevant information about the MSCH, your best choice in this situation is most likely D12.5. Bruce Pegg, BA, MA, CPC, CFPC, Managing Editor, AAPC
