Radiology Coding Alert

A 40-year-old female is referred by her primary physician to radiology for a screening mammogram. She has no initial signs or symptoms. On the same day as the screening (perhaps even within an hour), the radiologist interprets the screening results as abnormal and orders additional breast imaging right away.

When a screening mammogram (76092) becomes a diagnostic mammogram (76090, unilateral or 76091, bilateral) on the same day of service, the coder faces a number of challenging questions that must be answered in order to get accurately paid.

1. Is it correct to code the diagnostic mammogram and not the screening? Once the radiologist orders additional films after finding an abnormality as a result of screening, all on the same day of service, the mammography has become a diagnostic procedure, says Stacey Hall, ART, CPC, CCSP, director of corporate coding and documentation for Medical Management Professionals, Inc., in Knoxville, TN (a billing and practice management services firm). So, in this instance, the coder should not code for a screening mammogram. Instead, he or she should use the appropriate diagnostic code (76090, unilateral, left or right breast, or 76091, bilateral mammogram).

2. Is the GH modifier required for payment? Payment for a properly coded diagnostic mammogram should not be a problem with or without the modifier. However, the consensus among experienced coders is to use the GH modifier as a reporting mechanism to indicate that the diagnostic mammogram was converted from a screening on the same day of service. Hall adds that, the GH modifier was established by HCFA mainly for the purpose of collecting data on the number of diagnostic mammograms performed on Medicare patients as a result of screenings on the same day. The reason to use this modifier is to follow Medicare reporting procedures, but you wont find this modifier in AMAs CPT manual.

This actually means coders have a choice. If your policy is to limit the use of special modifiers whenever possible, the coder may want to use the GH where applicable for Medicare patients only. On the other hand, if this is another instance of Medicare leads, other payers follow and you wish to use this modifier consistently, the coder may want to use the modifier for all payers, relates Hall.

3. Is the choice of ICD-9-CM codes restricted in any way? While screening mammograms use the ICD-9-CM code V76.12 (special screening examination for malignant neoplasms, breast, unspecified), once the mammogram becomes diagnostic, the claim is subject to Medicare and other payer requirements for appropriate (payable) diagnoses to support medical necessity. For the administrative record, this does not call for changing the diagnosis code of V76.12 for the original screening mammogram. This simply means the procedure now encompasses further diagnostic evaluation and so additional diagnosis coding is required to show medical necessity.

Payers tend to be specific in identifying acceptable, payable ICD-9 codes in this instance. For example, Empire Medical Services (Medicare carrier for one of the largest populations in the northeast) states in one of its Medicare News Briefs (Part B), Diagnostic mammography is generally indicated when there are signs or symptoms suggestive of malignancy. They offer the following short list of acceptable ICD-9 codes to their providers:

172.5 - Malignant melanoma of skin of breast

173.5, 173.9 - Other malignant neoplasms

174.0-174.9 - Malignant neoplasm of female breast

175.0-175.9 - Malignant neoplasm of male breast

198.81 - Secondary neoplasm of breast

217 - Benign neoplasm of breast

232.5, 233.0 - Carcinoma in situ

238.3, 239.2, 239.3 - Neoplasm of uncertain behavior

451.89 - Thrombophlebitis of breast

610.0-610.9 - Benign mammary dysplasias

611.0-611.9 - Other disorders of breast

793.8 - Nonspecific abnormal findings on radiological and other examination of body structure, breast

V10.3 - Personal history of malignant neoplasm of breast

Empire states clearly, Only stated ICD-9 codes are payable. Payable diagnosis codes as well as payer guidance varies across Medicare carriers. Check with your local Medicare carrier to confirm the list of payable ICD-9 codes that apply in your area.

Coders and radiologists should be alert for referrals of women with higher than average risk for breast cancer. The problem from a coding perspective is the absence of relevant ICD-9-CM codes for certain conditions that support the medical necessity of mammography for this class of patients. Although the debate continues among physicians and organizations such as the American Cancer Society and the National Cancer Institute (NCI), it has been reported that NCIs National Cancer Advisory Board (NCAB) defined higher risk women as: Those who have had breast cancer; women carrying identified genetic alterations that may make them more susceptible to breast cancer; women in families in which multiple family members are affected with breast cancer, generally at younger ages; those with breast disease that may predispose them to cancer or those having had two or more breast biopsies for benign disease; women with 75 percent or more dense breast tissue on previous mammograms that made mammography reading difficult; or women having a first birth at age 30 or older.

Use the Table of Neoplasms in the ICD-9-CM Index, V codes, and the M codes listed in Appendix A, Morphology of Neoplasms when searching for appropriate codes for these high risk patients. However, with the exception of personal history of breast cancer (V10.3) and family history of breast cancer (V16.3), the other risk factors noted by the NCAB are hard to fit into any ICD-9 code. This is not surprising given that the diagnosis codes are designed to report diseases not risk factors.

So, what should a coder do? Technically, if you need to justify medical necessity of diagnostic mammography with any condition other than an ICD-9 code recognized as acceptable for payment by your local carrier, be prepared to respond to a denial with written justification asking for medical review. Given the definition of higher risk women provided by NCAB, and based on the clinical judgement of the referring physician and the radiologist, written justification may include known risk factors as well as disease conditions.

4. Which physicians UPIN is required in box 17 and 17a on HCFA-1500? Coders continue to receive conflicting guidance on UPIN requirements when a screening mammogram has become a diagnostic one. In these situations, effective July 1998, Medicare allowed radiologists to order additional mammography when a screening shows abnormalities.

Many local Medicare carriers then issued policies stating that if the radiologist ordered additional mammography, the UPIN of the radiologist would be required on the claim form instead of the referring physicians UPIN, says Hall. Since that time, and after much confusion over the issue, most carriers have gone back to requiring the UPIN of the referring physician in Block 17 and 17a of the 1500 claim form, according to Hall. However, NOT ALL have changed. To be safe, coders should check with their Medicare carrier and use the UPIN they require, either the referring physician or radiologist.