This article will be the first in a new series you can follow here on Coding Mastery called “Diagnosis Dilemmas.” While the focus of most of the articles I’ve shared has been CPT coding for surgical procedures which is my passion, I’ve been giving a lot of thought lately to how important diagnosis coding is as well. You can get your procedure codes right all day long, but if you don’t have a corresponding diagnosis that supports medical necessity and is coded accurately, you can still struggle to get your claims paid.
With that in mind, I decided that Coding Mastery was the perfect platform to start sharing some tips/tricks for sharpening your ICD-10-CM coding as well! Our first topic is one that really baffled me early in my coding career. When a physician documents a diagnosis of “mass” of an internal organ like the stomach, ovary, etc. how do you code that? If you look up the main term mass in the index of ICD-10-CM, you will notice there are some internal organs represented in that list including the liver, spleen, and the lungs. But there are many more sites in the human body where we find masses that are surgically removed or biopsied than what is listed under the term mass, and that is usually where the challenges come in.
Over the years, I’ve seen coders immediately go to the neoplasm table when they see the term “mass” in a report. I’ve also seen coders back out to a mass of the skin/subcutaneous tissue (e.g., R22.2 for a mass of the ovary). But neither of those solutions is quite right. The codes in the R22 series generally don’t support medical necessity for those deeper procedures on internal organs because the intent of those codes is to capture more superficial masses. If we look at the includes terms for category R22 in the tabular of ICD-10-CM, it includes conditions such as subcutaneous nodules that are localized and superficial. That doesn’t fit for masses of those deeper internal organs. Masses are also not synonymous with neoplasms. The term neoplasm means “new, abnormal growth,” and the term has a specific connotation that the growth may be either benign or malignant (cancerous). The term “mass” is a more generalized term for any abnormal clump of tissue and should not be considered a synonym with neoplasm.
To find a code for a “mass” of any anatomic site, we first need to start our search in the index of ICD-10-CM. You should actually start all diagnosis code searches this way because doing so ensures you see any redirects along the way and land on the most accurate code possible. When we look up the term mass, we have some options underneath the term mass and should select our code here if the subterm accurately reflects the anatomic site in our report. Let’s look at a visual of a search for the term mass in ICD-10-CM below to help:
As you can see, we have some but not all internal organs represented here. For example, if we were looking for the diagnosis for mass of the spleen, we could go to mass, splenic, and then to R16.1. When we look this code up in the tabular, we see it is for splenomegaly. The term splenomegaly means any abnormal enlargement of the spleen which can include a mass. So if you were coding for a mass of the spleen, your search could stop here.
The trouble comes in when we see that there are a limited number of organs represented in the subterms when searching on the term mass. So what happens if you can’t find the organ or structure where the mass is located in your report? We now need to follow the redirect for “specified organ NEC” – see disease, by site.
This redirect prompts us to start a completely new search with the main term of “disease” and then locate the subterm for the specific organ. For example, if you were looking for the code for a mass of the ovary, you would start with “mass” and find that there is no subterm for ovary underneath mass in the index. So follow the redirect to look for “disease, ovary.” I’ve included a visual of the available search results under “disease, ovary” below:
As you can see, we now have an option of N83.9 for “disease, ovary” (unspecified) and then another entry indented underneath that for “disease, ovary, specified NEC – N83.8.” This brings me to the second challenge in coding masses of various organs early in my coding career. If you search for disease of different organs, some organs/sites have code options for disease of that organ unspecified and a separate option for disease of that organ specified NEC. So which one do you pick?
I can share that I’ve had the privilege of working with many brilliant auditors and coders in my career, and we would always struggle to get everyone on the same page with which code to pick in this scenario. Some auditors would say the redirect said to go to “disease, by site” (not “disease, by site, specified NEC”) so the first option of disease, unspecified should be selected. Others would argue that a “mass” by definition is some “specified” type of disease so to code an unspecified code would be inaccurate; therefore, disease, by site, specified NEC should be selected (when available). A couple of years back, I had the opportunity to ask this question directly of the American Hospital Association (AHA), the leading organization that publishes the ICD-10-CM codes and guidelines. Our team submitted a query for advice to try to promote consistency in how we coded the term “mass” when we ended up following that redirect to see disease, by site. The AHA came back and recommended reporting the ICD-10-CM code for “disease, by site, specified NEC” when a specified NEC code exists for that organ/site. Because a mass is a type of specified disease, this makes perfect sense to me. So if you too have been wondering which code to select in this scenario, there’s your answer straight from an authoritative resource.
I hope this new series will be beneficial for you and welcome your feedback on coding dilemmas you would like to see addressed in a future article.