C51
Malignant neoplasm of vulva
C51 is a non-billable ICD-10-CM code category for malignant neoplasm of vulva. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are C51.0 Malignant neoplasm of labium majus, C51.1 Malignant neoplasm of labium minus, C51.2 Malignant neoplasm of clitoris, C51.8 Malignant neoplasm of overlapping sites of vulva and 1 more. Its coding notes include 1 Excludes1 entry.
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
A primary malignancy code stays in use until treatment directed at that site is completed. After that, with no evidence of disease at the site, Z85 gives the former site.
Excludes1
Not coded here. The listed conditions generally should not be reported together.
- carcinoma in situ of vulva (D07.1)
Includes
Further defines or gives examples of the content of the category.
Also from chapter/block level (1 note)
- malignant neoplasm of skin of female genital organs
Notes
Also from chapter/block level (8 notes)
- Functional activity
- All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
- Morphology [Histology]
- Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
- Primary malignant neoplasms overlapping site boundaries
- A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
- Malignant neoplasm of ectopic tissue
- Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).