ICD 10 Coding Alert

Question: The pathology report for our patient being investigated for ovarian cancer mentions “Serous tumor of low malignant potential (atypical proliferative serous tumor of ovary).” Can we report code C56.- for this diagnosis?

Nebraska Subscriber

Answer: Low malignant potential tumors are also known as borderline tumors according to the American Cancer Society (Source: www.cancer.org/cancer/ovarian-cancer/ treating/low-malignant-potential.html), and as such, cannot be reported as malignant with a code from:

• C56.1 (Malignant neoplasm of right ovary)
• C56.2 (… left ovary)
• C56.9 (... unspecified ovary).

Instead, you should think of it as a tumor of uncertain behavior, and you should use one of the following, as applicable and determined upon pathology and provider notation:

• D39.10 (Neoplasm of uncertain behavior of unspecified ovary)
• D39.11 (… of right ovary)
• D39.12 (… of left ovary).