Oncology & Hematology Coding Alert

Learn which code to add for patients on tamoxifen therapy.

Skipping secondary ICD-10-CM codes can be tempting, but properly reporting estrogen receptor status is a quick way to add support to a breast cancer patients’ claims. Shore up Z17.- coding skills with the answers to three key questions.

Important:  These questions and answers relate to patients being treated for breast cancer currently present, not for patients on prophylactic regimens.

1. What Do ER+ and ER- Refer To?

The following codes describe estrogen receptor status:

• Z17.0 (Estrogen receptor positive status [ER+])
• Z17.1 (Estrogen receptor negative status [ER-]).

When a neoplasm is ER+, estrogen is fueling the cancer and causing it to grow. As a result, ER+ cancer should respond to hormone therapy. ER- cancers won’t respond as well to hormone therapy. So, the estrogen receptor (ER) status is important information for the oncologist making treatment decisions.

Treatments: New ICD-10-CM Z17.0 may help support hormone therapies that include the following:

• Selective estrogen receptor modulators (SERMs), such as oral drug tamoxifen (Nolvadex)
• Aromatase inhibitors (AIs), including oral drugs anastrazole (Arimidex) and letrozole (Femara)
• Estrogen-receptor down regulators (ERDs), such as fulvestrant (Faslodex) for post-menopausal women with advanced breast cancer has stopped responding to other anti-estrogen therapy.

Caution: Do not report these orally administered drugs on your part B claim.

But providers administer fulvestrant (J9395, Injection, fulvestrant, 25 mg) as an intramuscular injection. So, if you supply the administered drug, report the HCPCS code representing it on the claim. Fulvestrant is given as a 250 mg dose, so be sure to report 10 units of J9395. Your administration code may vary depending on the payer. Report chemotherapy administration code 96402 (Chemotherapy administration, subcutaneous or intramuscular; hormonal anti-neoplastic) for fulvestrantadministration.

Other payers may categorize fulvestrant as a non-antineoplastic hormonal treatment and require reporting 96372 (Therapeutic, prophylactic, or diagnostic injection [specify substance or drug]; subcutaneous or intramuscular). CPT^® guidelines indicate reporting 96372 for non-antineoplastic hormonal therapy injections.

2. Who Identifies ER Status?

A lab test will reveal the patient’s estrogen receptor status. Depending on whether the lab performs an analysis that is qualitative, semi-quantitative, or quantitative, and whether the technique is manual or automated, the lab should consider the following three codes:

• 88342 (Immunohistochemistry or immunocytochemistry, per specimen; initial single antibody stain procedure)
• 88360 (Morphometric analysis, tumor immunohis­tochemistry [e.g., Her-2/neu, estrogen receptor/ progesterone receptor], quantitative or semiquan­titative, per specimen, each single antibody stain procedure; manual)
• 88361 ( ...  using computer-assisted technology).

The American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) recommend designating a tumor as ER positive if at least one percent of the cells examined test positive. You may see results recorded as positive or negative, as a percentage (between 0 percent and 100 percent), or as a score:

• 0 for no receptors found
• 1+ for a small number of receptors found
• 2+ for a medium number
• 3+ for a large number.

Rule: Base the diagnosis code selection on the physician’s documented interpretation of the test.

Remember, ICD-10-CM guidelines state: “For outpatient encounters for diagnostic tests that have been interpreted by a physician, and the final report is available at the time of coding, code any confirmed or definitive diagnosis(es) documented in the interpretation. Do not code related signs and symptoms as additional diagnoses.”

3. Should Z17.- Be First-Listed?

For a patient who is currently being treated for breast cancer, when submitting a Z17.- code, be sure to follow ICD-10-CM guidelines regarding the reporting order. A note with the Z17 codes states, “Code first malignant neoplasm of breast (C50.-).” ICD-10-CM rules state the “code first” instruction “directs the coder to sequence the underlying condition before the manifestation.” So, report the neoplasm before reporting the estrogen status.

Similarly, notes with C50.- instruct you to “Use additional code to identify estrogen receptor status (Z17.0, Z17.1).” The “use additional code” instruction means “another code may be needed,” ICD-10-CM states. So, if a breast cancer patient has been tested for estrogen receptor status, report the appropriate Z17.- code secondary to the malignant neoplasm code.

Example: To code a visit for a female patient with breast cancer (ER+ status) being treated with tamoxifen, report C50.-, says Melanie Witt, RN, MA, an independent coding expert based in Guadalupita, New Mexico.

If possible, be specific with the primary breast cancer code. Review the chart for the location of the breast mass. It is possible to have two masses in different locations of the breast, and when this occurs both breast cancer codes should be reported,” Witt says. For example, you may report C50.211 (Malignant neoplasm of upper-inner quadrant of right female breast) and C50.412 (Malignant neoplasm of upper-outer quadrant or left female breast) together, she says.

As an additional diagnosis, list Z17.0 (ER+ status). Plus, “if the chart note mentions family history of breast cancer, code Z80.3 (Family history of malignant neoplasm of breast) may also be added as a secondary diagnosis,” Witt notes.

In addition, Z79.899 (Other long-term (current) drug therapy) is appropriate when the patient is taking tamoxifen as part of current cancer treatment. Also check for other appropriate Z codes, such as Z51.81 (Encounter for therapeutic drug level monitoring) when the patient presents to monitor the drug’s effect.

Please note: Oncologists may prescribe tamoxifen for prevention as well as for treatment of cancer, so pay close attention to the documentation. Look to a future issue for information on coding for patients taking tamoxifen as a preventative measure.