Is C48 a billable ICD-10-CM code?

No. C48 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does C48 sit in the tabular list?

Neoplasms (C00-D49), in the block Malignant neoplasms of mesothelial and soft tissue (C45-C49).

What cannot be coded together with C48?

C48 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

C48

C48 — Malignant neoplasm of retroperitoneum and peritoneum

Non-billable headerICD-10-CM

C48 is a non-billable header ICD-10-CM code for malignant neoplasm of retroperitoneum and peritoneum. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

Kaposi's sarcoma of connective tissue (C46.1)
mesothelioma (C45.-)

Other codes that can never be billed with C48

These codes carry an Excludes1 note pointing at C48. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading C48 alone.

C26Malignant neoplasm of other and ill-defined digestive organs
C45.1Mesothelioma of peritoneum

Risk adjustment

C48 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead C48

4 child codes. Green means billable.

Questions about C48

Is C48 a billable ICD-10-CM code?: No. C48 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does C48 sit in the tabular list?: Neoplasms (C00-D49), in the block Malignant neoplasms of mesothelial and soft tissue (C45-C49).
What cannot be coded together with C48?: C48 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.