ICD-10-CM 2027 diagnosis code

C48Malignant neoplasm of retroperitoneum and peritoneum

Not billable — use a more specific code

C48 is a header code, so it can't be reported by itself. Choose one of the 4 more specific codes beneath it.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About C48

C48 is the ICD-10-CM diagnosis code for malignant neoplasm of retroperitoneum and peritoneum. It belongs to block C45-C49 (malignant neoplasms of mesothelial and soft tissue) and chapter 2 (neoplasms). It is a header code, so it can't be reported by itself; one of its 4 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: C48.0 (retroperitoneum), C48.1 (peritoneum), C48.2 (unspecified) and C48.8 (peritoneum).

Don't report C48 together with the conditions in its Excludes1 note: Kaposi's sarcoma of connective tissue (C46.1) and mesothelioma (C45.-).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under C48

Coding notes

Excludes1Not coded here — never report together with this code

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

Notes that apply from higher levels

Instructions written at a parent level also apply to C48.

Broader instructions also apply from Chapter 2: Neoplasms.

Codes whose notes reference C48

C26Excludes1
C45.1Excludes1

Code history

2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about C48

Is C48 billable?: No. C48 is a header code. Report one of its more specific subcodes instead.