What is the ICD-10 (International Classification of Diseases, 10th Revision) code for a diagnostic mammogram?

ICD-10 Codes for Diagnostic Mammogram

The ICD-10 code for a diagnostic mammogram is Z12.31 (encounter for screening mammogram for malignant neoplasm of breast).

Diagnostic Mammogram Coding Framework

Diagnostic mammograms require proper coding to ensure appropriate reimbursement and accurate medical documentation. The coding depends on the clinical scenario:

Primary Diagnostic Codes

1. Screening mammogram:

   • Z12.31: Encounter for screening mammogram for malignant neoplasm of breast

2. Diagnostic mammogram for specific symptoms:

   • N63: Unspecified lump in breast
   • R92.0: Mammographic microcalcification found on diagnostic imaging of breast
   • R92.1: Mammographic calcification found on diagnostic imaging of breast
   • R92.2: Inconclusive mammogram
   • R92.8: Other abnormal and inconclusive findings on diagnostic imaging of breast

3. Diagnostic mammogram for pathologic nipple discharge:

   • N64.52: Nipple discharge
   • R92.8: Other abnormal findings on diagnostic imaging of breast

Secondary Diagnostic Codes

When coding for diagnostic mammograms, include relevant secondary codes to support medical necessity:

• Personal history codes:

  • Z85.3: Personal history of malignant neoplasm of breast
  • Z86.000: Personal history of in-situ neoplasm of breast

• Family history codes:

  • Z80.3: Family history of malignant neoplasm of breast

• High-risk factors:

  • Z15.01: Genetic susceptibility to malignant neoplasm of breast
  • Z15.02: Genetic susceptibility to malignant neoplasm of ovary

Clinical Scenarios and Appropriate Coding

Scenario 1: Diagnostic Mammogram for Palpable Mass

• Primary code: N63 (Unspecified lump in breast)
• Secondary code: Z12.31 (Encounter for screening mammogram)

According to the ACR Appropriateness Criteria, diagnostic mammography receives a rating of 9 (usually appropriate) for patients with palpable breast masses, especially in those 40 years or older 1.

Scenario 2: Diagnostic Mammogram for Nipple Discharge

• Primary code: N64.52 (Nipple discharge)
• Secondary code: R92.8 (Other abnormal findings on diagnostic imaging of breast)

For pathologic nipple discharge in patients 40 years or older, diagnostic mammography receives a rating of 9 (usually appropriate) per ACR guidelines 1.

Scenario 3: Surveillance After Breast Cancer Treatment

• Primary code: Z85.3 (Personal history of malignant neoplasm of breast)
• Secondary code: Z12.31 (Encounter for screening mammogram)

For surveillance to rule out local recurrence, diagnostic mammography receives a rating of 9 (usually appropriate) 1.

Common Coding Pitfalls

1. Using screening codes for diagnostic exams:

   • Ensure Z12.31 is only used for screening, not diagnostic examinations

2. Missing secondary diagnosis codes:

   • Always include the medical reason for the diagnostic mammogram

3. Incorrect sequencing:

   • The symptom or condition prompting the diagnostic mammogram should be listed as the primary diagnosis

4. Failure to document medical necessity:

   • Include appropriate documentation to support the need for a diagnostic rather than screening mammogram

Coding Best Practices

1. Review the patient's clinical history thoroughly before assigning codes
2. Document specific findings that prompted the diagnostic mammogram
3. Include any relevant personal or family history codes
4. Ensure proper sequencing of primary and secondary diagnosis codes
5. Update coding practices as ICD-10 guidelines evolve

Remember that proper coding is essential not only for reimbursement but also for accurate tracking of breast cancer screening and diagnostic efforts in the population 2.