Otolaryngology Coding Alert

Learn the right way to code metastatic cancers.

If you’re new to coding cancers of the head and neck, the ICD-10 Table of Neoplasms can be confusing to use at first. And if you’re a seasoned pro, there’s a chance you may not be using it correctly.

So, what is the best way to use the table to ensure proper coding? Jill Young, CEMC, CPC, CEDC, CIMC, of Young Medical Consulting LLC in East Lansing, Michigan, lays out four useful pointers that you can use the next time you try to locate a neoplasm in the table.

Tip 1: Use the Alphabetic Index First

As tempting as it may be for you to go straight to the neoplasm table to find the code that best describes the patient’s condition, the first step to correct neoplasm coding is to “rely on the Alphabetic Index when a specific neoplasm does not appear in the neoplasm table” advises Barbara J. Cobuzzi, MBA, CPC, COC, CPC-P, CPC-I, CENTC, CPCO, CMCS, of CRN Healthcare Solutions of Tinton Falls, New Jersey

ICD-10 guidelines support this method of locating the correct code. Specifically, “the neoplasm table in the Alphabetic Index should be referenced first. However, if the histological term is documented, that term should be referenced first, rather than going immediately to the Neoplasm Table, in order to determine which column in the Neoplasm Table is appropriate,” according to the general ICD-10 guidelines accompanying Chapter 2.

Why? Simply, not all neoplasms appear in the neoplasm table. Looking for esthesioneuroblastoma, a rare cancer that begins in the nasal cavity? It isn’t there. But a visit to the Alphabetic Index immediately directs you to C30.0 (Malignant neoplasm of nasal cavity).

But remember: As the instructions for using the Table of Neoplasms state, “guidance in the ICD-10 Index can be overridden if one of the descriptors mentioned above [malignant, benign, in situ, of uncertain behavior, or of unspecified behavior] is present; e.g., malignant adenoma of colon is coded to C18.9 [Malignant neoplasm of colon, unspecified] and not to D12.6 [Benign neoplasm of colon, unspecified] as the adjective ‘malignant’ overrides the Index entry ‘Adenoma—see also Neoplasm, benign, by site.’”

Tip 2: Don’t Ignore the Tabular List

Sometimes, the Alphabetic Index won’t give you all the information you need for precise coding. For example, consider how you would code a primary malignant neoplasm of the minor salivary gland or duct. In this situation, the Alphabetic Index won’t help you narrow the code choice down, as the term “salivary duct or gland” simply directs you to “see condition.”

However, if you look for the terms in the table, you are directed to a number of options, including:

• C06.9 (Malignant neoplasm of mouth, unspecified)
• C07 (Malignant neoplasm of parotid gland)
• C08.9 (Malignant neoplasm of major salivary gland, unspecified)

You should then turn to the tabular list and verify your choice, which will enable you to confirm that C06.9 is the correct code to use for a malignant neoplasm of the minor salivary gland, as malignant neoplasm of the minor salivary gland is one of the inclusion terms for the code.

And remember: The Tabular List contains additional instructional information that goes beyond that contained in the neoplasm table and Alphabetic Index, including Not elsewhere classified (NEC), Not otherwise specified (NOS), Excludes, and Code first/Use additional code guidelines.

This is important in our example of coding salivary duct or gland cancer, as all the possible code options contain the instruction to use an additional code to identify alcohol abuse and dependence (F10.-), a history of tobacco dependence (Z87.891), tobacco dependence (F17.-), and tobacco use (Z72.0).

While it may feel like a fire drill at times, you should always follow through the whole coding process and verify the code choice in the Tabular List to avoid making hasty coding mistakes.

Tip 3: Understand Uncertain/Unspecified

The columns for uncertain behavior and unspecified behavior in the neoplasm table can also be subject to misunderstanding, Young cautions. The two are not the same and are not interchangeable.

Uncertain behavior codes are used in circumstances where a pathologist’s report specifically states that the histologic behavior of the cancer cannot be determined or predicted based on current testing. In other words, the neoplasm table tells you to assign D48.1 (Neoplasm of uncertain behavior of connective and other soft tissue) for cancer of the neck if the pathology report states the specimen’s behavior is uncertain. This would be because the pathologist cannot provide “histologic confirmation whether the neoplasm is malignant or benign,” per the note for the D37-D44 and D48 codes.

Unspecified behavior codes are used “when the information in the medical record is insufficient to assign a more specific code” per ICD-10 guideline I.A.9.b. So, you should assign a code from this column when the provider is certain that a patient has a cancer but cannot assign a more specific code for that cancer. For example, you would code a patient with a confirmed diagnosis of neck cancer with unspecified code D49.2 (Neoplasm of unspecified behavior of bone, soft tissue, and skin) if there is no documentation that the cancer is in an anatomic location which has its own, more specific code.

Tip 4: Remember Primary and Secondary Mean Different Things

The table’s designations of malignant neoplasms as either primary (where the neoplasm originated), secondary (where it has spread to, or metastasized), or in situ (a neoplasm that does not spread past the site of origin) are important for many reasons. But from a coding perspective, sometimes a secondary neoplasm can be coded as a primary diagnosis, and vice versa.

Why? “If the treatment is directed at a malignancy, then that malignancy would be regarded as the principal diagnosis. In other words, if the treatment is directed to a secondary malignancy, that is principal diagnosis in this specific encounter,” said Young.

Example: A patient has nasopharyngeal cancer that has spread to the lymph nodes in the neck and is reporting to your provider for treatment of the cancer that has now metastasized to the lymph nodes. In this example, the patient still has nasopharyngeal cancer, but the primary diagnosis code you would use for the encounter is the metastatic, or secondary, lymph node cancer because that is what the provider is treating, not the nasopharyngeal cancer.

So, you would not code the nasopharyngeal cancer (C11.9, Malignant neoplasm of nasopharynx, unspecified) first, as that is not what is being treated at this encounter. And neither would you code C49.9 (Malignant neoplasm of connective and soft tissue, unspecified) because the lymph node cancer being treated is not the primary cancer. You also should not report C79.89 (Secondary malignant neoplasm of other specified sites) because the nasopharyngeal cancer is not metastatic to the lymph nodes. Instead, as the treatment is directed to the lymph nodes, you will use C77.0 (Secondary and unspecified malignant neoplasm of lymph nodes of head, face and neck) as the principal diagnosis for this encounter.

A note of caution: For metastatic cancers, always closely scrutinize your provider’s documentation. “If your provider notes the cancer is metastatic to, that means the cancer is secondary. If the note reads metastatic from, that means the cancer is primary,” Young noted (emphasis added).