QA1.798Other inherited neoplasm predisposition syndrome of multiple systems

QA1.798 is the ICD-10-CM diagnosis code for other inherited neoplasm predisposition syndrome of multiple systems. It belongs to category QA1 (genetic disorders associated with neoplasms, not elsewhere classified), block QA0-QA1 (genetic disorders, not elsewhere classified) and chapter 17 (congenital malformations, deformations, chromosomal abnormalities, and genetic disorders). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within QA1.79, choose QA1.798 (Other inherited neoplasm predisposition syndrome of multiple systems) only when documentation doesn't support a more specific option: familial cancer syndrome with pathogenic BRCA1 mutation (QA1.790), familial cancer syndrome with pathogenic BRCA2 mutation (QA1.791) and Li Fraumeni syndrome (QA1.792).

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 951 (Other Factors Influencing Health Status, relative weight 0.5577), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.

It was added in FY2027, effective October 1, 2026.