MS-DRG 599: MALIGNANT BREAST DISORDERS WITHOUT CC/MCC
MS-DRG 599 is malignant breast disorders without cc/mcc, in MDC 09 (a medical DRG), at the without-CC/MCC level. Its FY2027 relative weight is 0.6925, so a case here pays less than the average Medicare inpatient stay (weight 1.0), with a geometric mean length of stay of 1.80 days. 74 ICD-10-CM principal diagnoses group into MS-DRGs 597–599 under the CMS definitions manual; the most-searched are listed below.
FY2027 payment factors
- Relative weight
- 0.6925
- Geometric mean LOS
- 1.80
- Arithmetic mean LOS
- 2.20
- Post-acute transfer
- No
CMS caps year-over-year weight decreases at 10%. Before the cap this DRG weighs 0.6759; the capped weight above is the one used for payment. 41 DRGs differ this way in FY2027.
Principal diagnoses that group to MS-DRGs 597–599
From the CMS MS-DRG definitions manual’s principal-diagnosis index: 74 ICD-10-CM codes route here, and the CC/MCC status of the secondary diagnoses decides which of 597–599 the case lands in. The 24 most-searched:
- C50.911Malignant neoplasm of unspecified site of right female breast
- C50.912Malignant neoplasm of unspecified site of left female breast
- C50.919Malignant neoplasm of unspecified site of unspecified female breast
- C50.411Malignant neoplasm of upper-outer quadrant of right female breast
- C50.412Malignant neoplasm of upper-outer quadrant of left female breast
- C50.211Malignant neoplasm of upper-inner quadrant of right female breast
- C50.811Malignant neoplasm of overlapping sites of right female breast
- C50.812Malignant neoplasm of overlapping sites of left female breast
- D05.11Intraductal carcinoma in situ of right breast
- D05.12Intraductal carcinoma in situ of left breast
- C50.111Malignant neoplasm of central portion of right female breast
- C50.212Malignant neoplasm of upper-inner quadrant of left female breast
- C50.511Malignant neoplasm of lower-outer quadrant of right female breast
- C50.512Malignant neoplasm of lower-outer quadrant of left female breast
- C50.112Malignant neoplasm of central portion of left female breast
- C50.312Malignant neoplasm of lower-inner quadrant of left female breast
- C50.011Malignant neoplasm of nipple and areola, right female breast
- C50.311Malignant neoplasm of lower-inner quadrant of right female breast
- C79.81Secondary malignant neoplasm of breast
- C50.012Malignant neoplasm of nipple and areola, left female breast
- C50.A1Malignant inflammatory neoplasm of right breast
- C50.A2Malignant inflammatory neoplasm of left breast
- C79.2Secondary malignant neoplasm of skin
- D48.62Neoplasm of uncertain behavior of left breast
50 more codes group here. Open any code above for its full hierarchy, or check a whole claim in the free DRG calculator.
The severity splits
Same base DRG, split by whether a secondary diagnosis is a CC or MCC. The last column is the weight change from MS-DRG 599.
| 597 | MALIGNANT BREAST DISORDERS WITH MCC | 1.7383 | +1.0458 |
| 598 | MALIGNANT BREAST DISORDERS WITH CC | 1.0962 | +0.4037 |
| 599 | MALIGNANT BREAST DISORDERS WITHOUT CC/MCC | 0.6925 |
All FY2027 MS-DRGs · MDC 09