General Surgery Coding Alert

Wait for pathology report, if possible.

When your surgeon performs a procedure that results in a cancer diagnosis, you’ll need to gather lots of medical details from the op report and the pathology report before you can code the case with precision.

“Coders need to take various factors into consideration when coding neoplasms of various behaviors, such as the areas affected, primary versus secondary status, and cancer in situ,” says Lindsay Della Vella, COC, medical coding auditor at Precision Healthcare Management in Media, Pennsylvania.

Opportunity: Look at our experts’ comments on the following cases for some learning tips and techniques that will have you coding neoplasms with confidence and accuracy in no time.

Example 1: Mucoepidermoid Carcinoma

The surgical report documents a simple parotidectomy of a superficial lobe of the left parotid gland without facial-nerve involvement. The initial diagnosis is “parotid mass.” Code the procedure as 42410 (Excision of parotid tumor or parotid gland; lateral lobe, without nerve dissection).

The pathology report in this case concludes that the specimen is a “mucoepidermoid carcinoma.” You should always wait for the pathology report, if at all possible, and code the most specific diagnosis available at the time of billing.

Before attempting to find the correct diagnosis code, you want to make sure you’ve got a firm understanding of the type of neoplasm you’re dealing with. In this case, you already know the behavior of the neoplasm, because you should identify as “malignant,” any neoplasm labeled as a carcinoma.

From there, it gets a little trickier. You won’t find the scientific term “mucoepidermoid carcinoma” anywhere in the Table of Neoplasms or ICD-10 index, so you’ve got to come up with another game plan to determine the most accurate diagnosis code available.

Keep it Simple: Use a Medical Dictionary

Some coders might opt to take the approach of dividing the diagnosis between prefix, root word, and suffix. “Coders need to be careful when going this route,” advises Barry Rosenberg, MD, chief of radiology at United Memorial Medical Center in Batavia, New York. “If a coder does not have a fundamental understanding of the anatomy behind the codes they are researching, they may wind up reaching some inaccurate conclusions,” he says.

Breaking apart this diagnosis, you see that the prefix, muco-, is defined by Stedman’s Medical Dictionary as “mucus, mucous (mucous membrane).” Epidermoid, on the other hand, is defined as “resembling epidermis.” Based on these two definitions, the malignancy might pertain to any one of numerous mucus-producing organs. Since both the respiratory and digestive tracts produce mucus to line the passageways, this route seems to leave the coder at a dead end.

Fortunately, you will rarely, if ever, have to rely on prefixes and root words to identify a neoplasm. Most medical dictionaries have definitions for any and all neoplasm diagnoses in existence. Stedman’s identifies a mucoepidermoid carcinoma as “most commonly a salivary gland carcinoma of low-grade malignancy composed of mucous, epidermoid, and intermediate cells, with mucous cells abundant only in low-grade carcinoma; recurrence is frequent, and high-grade carcinomas metastasize to cervical nodes.”

Rely on Physician Documentation

While the Stedman’s definition offers a substantially higher degree of specificity than you had previously, you’re still not left with any definitive location of the cancer. This is where the provider’s documentation comes into play. Whether you are coding from an operative note or the pathology report, the provider should offer enough elaboration to identify the specific anatomic site of the tumor specimen. Although a mucoepidermoid carcinoma may occur in various locations, such as a salivary gland or thyroid gland, you have documentation that indicates the tumor was in the left parotid gland.

The term “carcinoma,” in the ICD-10 index leads you to “see also Neoplasm, by site, malignant.” That means your next step to coding this case is to turn to “parotid gland” in the Table of Neoplasms, which lists C07 (Malignant neoplasm of parotid gland). Next, you will identify malignant neoplasm of parotid gland as C07 (Malignant neoplasm of parotid gland). Make sure to evaluate the options of a secondary code for tobacco and alcohol use, if applicable.

Example 2: Verrucous Carcinoma

The op report in this case indicates that the surgeon removed a mass from the “retromolar trigone” and performed a flap closure using bordering buccal tissue. You should code the procedure as 42844 (Radical resection of tonsil, tonsillar pillars, and/or retromolar trigone; closure with local flap (eg, tongue, buccal)).

Using the knowledge from the previous example, coding a case that the pathologist identifies as a “verrucous carcinoma” should feel like a less daunting task. Again, you will not find verrucous carcinoma in either the ICD-10 index or the Table of Neoplasms, so all you know initially is that you are dealing with a neoplasm of malignant behavior (carcinoma).

Having learned the pitfalls of relying on the prefix, suffix, or root words, your next step is to find the clinical definition for verrucous carcinoma. Stedman’s Medical Dictionary defines a verrucous carcinoma as “a well-differentiated papillary squamous cell carcinoma, especially of the oral cavity or penis, which may invade locally but rarely metastasizes; the usual cytologic features of malignancy are absent.”

Rely on Your Deductive Reasoning Skills

The term, “trigone” refers to a triangular area of tissue. In this case, the term “retromolar” refers to a small region behind the wisdom teeth, which is in the oral cavity.

When you look at the Table of Neoplasms under “oral cavity,” ICD-10-CM refers you to C06.9 (Malignant neoplasm of mouth, unspecified) for a primary malignancy. But you know that this specimen is not from an unspecified site. That means you’ll need to use your deductive reasoning skills to find the best code for this scenario.

Codes C01-C06 refer to malignant neoplasms of the oral cavity, mostly of specific sites. As you look through the codes in this range, you’ll find C06.2 (Malignant neoplasm of retromolar area) which more accurately describes this case than the “unspecified” code C06.9.

Avoid this error: Coders sometimes think that if they don’t have a pathology report that definitively identifies the tumor behavior, they should just say that the tumor is of “uncertain behavior.” That’s wrong. “Uncertain behavior” describes a tumor that is currently considered benign, but that the pathologist thinks may become malignant over time.

Do this: If you don’t have specific information about tumor behavior, you can list the code for “unspecified behavior,” but never use the code for “uncertain behavior” in these circumstances.