ICD-10 · PDGM grouping

C45-C49 — Malignant neoplasms of mesothelial and soft tissue

Every ICD-10-CM code in this range and the PDGM clinical group CMS assigns to it, read from the CMS grouper crosswalk v07.1.26.

OASIS-E2 v1.00.0 · ingested 2026-04-26

Codes in range

No clinical group

A period cannot be grouped from these.

Barred as primary

CMS rejects these in the primary position.

Where these codes group

43 of the 52 codes in C45-C49 group to MMTA - Infectious Disease, Neoplasms, and Blood-Forming Diseases. A further 9 are assigned no clinical group at all, which means a 30-day period cannot be grouped from them.

KMMTA - Infectious Disease, Neoplasms, and Blood-Forming Diseases43

Every code in C45-C49

Descriptions are CMS’s own, abbreviated as CMS abbreviates them.

Code	Description	Clinical group	Primary position
C450	Mesothelioma of pleura	K	Accepted
C451	Mesothelioma of peritoneum	K	Accepted
C452	Mesothelioma of pericardium	K	Accepted
C457	Mesothelioma of other sites	K	Accepted
C459	Mesothelioma, unspecified	None	Cannot group
C460	Kaposi's sarcoma of skin	K	Accepted
C461	Kaposi's sarcoma of soft tissue	K	Accepted
C462	Kaposi's sarcoma of palate	K	Accepted
C463	Kaposi's sarcoma of lymph nodes	K	Accepted
C464	Kaposi's sarcoma of gastrointestinal sites	K	Accepted
C4650	Kaposi's sarcoma of unspecified lung	None	Cannot group
C4651	Kaposi's sarcoma of right lung	K	Accepted
C4652	Kaposi's sarcoma of left lung	K	Accepted
C467	Kaposi's sarcoma of other sites	K	Accepted
C469	Kaposi's sarcoma, unspecified	None	Cannot group
C470	Malignant neoplasm of prph nerves of head, face and neck	K	Accepted
C4710	Malig neoplm of prph nerves of unsp upper limb, inc shoulder	None	Cannot group
C4711	Malig neoplm of prph nerves of right upper limb, inc shldr	K	Accepted
C4712	Malig neoplm of prph nerves of left upper limb, inc shoulder	K	Accepted
C4720	Malig neoplasm of prph nerves of unsp lower limb, inc hip	None	Cannot group
C4721	Malig neoplasm of prph nerves of right lower limb, inc hip	K	Accepted
C4722	Malig neoplasm of prph nerves of left lower limb, inc hip	K	Accepted
C473	Malignant neoplasm of peripheral nerves of thorax	K	Accepted
C474	Malignant neoplasm of peripheral nerves of abdomen	K	Accepted
C475	Malignant neoplasm of peripheral nerves of pelvis	K	Accepted
C476	Malignant neoplasm of peripheral nerves of trunk, unsp	K	Accepted
C478	Malig neoplm of ovrlp sites of prph nrv and autonm nrv sys	K	Accepted
C479	Malig neoplasm of prph nerves and autonm nervous sys, unsp	K	Accepted
C480	Malignant neoplasm of retroperitoneum	K	Accepted
C481	Malignant neoplasm of specified parts of peritoneum	K	Accepted
C482	Malignant neoplasm of peritoneum, unspecified	K	Accepted
C488	Malig neoplasm of ovrlp sites of retroperiton and peritoneum	K	Accepted
C490	Malig neoplm of conn and soft tissue of head, face and neck	K	Accepted
C4910	Malig neoplm of conn & soft tiss of unsp upr lmb, inc shldr	None	Cannot group
C4911	Malig neoplm of conn and soft tiss of r upr limb, inc shldr	K	Accepted
C4912	Malig neoplm of conn and soft tiss of l upr limb, inc shldr	K	Accepted
C4920	Malig neoplm of conn and soft tiss of unsp low limb, inc hip	None	Cannot group
C4921	Malig neoplm of conn and soft tiss of r low limb, inc hip	K	Accepted
C4922	Malig neoplm of conn and soft tiss of left low limb, inc hip	K	Accepted
C493	Malignant neoplasm of connective and soft tissue of thorax	K	Accepted
C494	Malignant neoplasm of connective and soft tissue of abdomen	K	Accepted
C495	Malignant neoplasm of connective and soft tissue of pelvis	K	Accepted
C496	Malignant neoplasm of conn and soft tissue of trunk, unsp	K	Accepted
C498	Malignant neoplasm of ovrlp sites of conn and soft tissue	K	Accepted
C499	Malignant neoplasm of connective and soft tissue, unsp	None	Cannot group
C49A0	Gastrointestinal stromal tumor, unspecified site	None	Cannot group
C49A1	Gastrointestinal stromal tumor of esophagus	K	Accepted
C49A2	Gastrointestinal stromal tumor of stomach	K	Accepted
C49A3	Gastrointestinal stromal tumor of small intestine	K	Accepted
C49A4	Gastrointestinal stromal tumor of large intestine	K	Accepted
C49A5	Gastrointestinal stromal tumor of rectum	K	Accepted
C49A9	Gastrointestinal stromal tumor of other sites	K	Accepted

Source: CMS HH PPS Grouper Software v07.1.26, effective 2026-04-01. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.

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C45-C49 — Malignant neoplasms of mesothelial and soft tissue

Where these codes group

Every code in C45-C49

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