ICD-10 code for fibrous mesothelioma

The ICD-10-CM code for fibrous mesothelioma is C45.9 (Mesothelioma, unspecified). The official index lists 7 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on C45.9.

Within C45, choose C45.9 (unspecified) only when documentation doesn't support a more specific option: of pleura (C45.0), of peritoneum (C45.1), of pericardium (C45.2) and of other sites (C45.7).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 826 (Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures with MCC, relative weight 4.7581), DRG 827 (Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures with CC, relative weight 2.3896), DRG 828 (Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Major O.R. Procedures without CC/MCC, relative weight 1.6955), DRG 829 (Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Other Procedures with CC/MCC, relative weight 3.1281), DRG 830 (Myeloproliferative Disorders or Poorly Differentiated Neoplasms with Other Procedures without CC/MCC, relative weight 1.4859), DRG 843 (Other Myeloproliferative Disorders or Poorly Differentiated Neoplastic Diagnoses with MCC, relative weight 1.9453) and 2 more, in MDC 17 (Myeloproliferative Diseases and Disorders, Poorly Differentiated Neoplasms), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.