Oncology & Hematology Coding Alert

And brush up on your medical terminology at the same time.

You probably already know that a blastoma is a type of cancer that predominantly — though not always — affects children. You might also know that, like all cancers, blastomas are assigned ICD-10-CM codes based on the anatomic location of the blastoma.

But there’s much more to blastoma diagnosis coding than meets the eye. That’s why we’ve created this guide to help increase your clinical understanding of the conditions and to allow you to find the precise diagnosis code for each one with ease. And, as a bonus, you’ll get a refresher on your clinical vocabulary.

Understand Blastomas

First, here’s a quick rundown of the condition’s etiology and characteristics.

Blastoma is a form of cancer that “affects a type of stem cell known as a precursor cell,” according to Medical News Today (www.medicalnewstoday.com/articles/301456). Precursor cells are capable of becoming any kind of cell within the body, and because of that, they are usually found in fetuses while they are in the process of developing into a fully formed human. So, because “a developing baby that is not yet born has more precursor cells than an adult because the body is still forming … blastoma is most common in children,” Medical News Today explains.

Medical terminology reminder: The term “blastoma” comes from the Greek term “blasto,” meaning “bud” or “sprout.” The term also appears in the word “blastocyst,” which refers to the ball of cells that eventually becomes a human embryo. The term points to the formative nature of the cells that this type of cancer affects.

Understand ICD-10-CM Coding for Blastomas

Finding a blastoma code can be tricky. That’s because when you look up the term blastoma in the ICD-10-CM Alphabetic Index, you’ll find it does not point to any specific codes. Instead, the index simply refers you back to the neoplasm codes; in other words, there is no separate blastoma section within the neoplasm codes.

Then, you have an additional problem, as one blastoma, pleuropulmonary, does not appear in ICD-10-CM, and others, such as neuroblastoma, have directions to code by site like any other malignant neoplasms. Worse yet, none appear as inclusion terms for anatomically related neoplasm codes. This means finding the particular code for a specific blastoma can be really tricky unless you can spot the anatomical suffixes that precede the term “blastoma.”

The following is a guide to the most common blastomas with their associated ICD-10-CM code. We’ve included some information about blastoma clinical terms to help you zero in on the diagnosis code whenever ICD-10-CM does not point to a specific blastoma code.

Understand Limitations of Clinical Terms

As useful as knowing prefixes, suffixes, and roots can be in precise blastoma coding, you should always be wary of defining diagnoses this way. That’s because “if you don’t have a fundamental understanding of the anatomy behind the codes, you may wind up reaching some inaccurate conclusions,” advises Barry Rosenberg, MD, chief of radiology at United Memorial Medical Center in Batavia, New York.

For example, you should not rely on the prefix in an attempt to find the correct diagnosis code for medulloblastoma. The prefix “medullo” pertains to “medulla,” a “soft marrowlike structure, especially in the center of a part,” according to Stedman’s Medical Dictionary, and not to the medulla oblongata, which is an entirely separate entity from the cerebellum.

And Remember These Blastoma Laterality Nuances

In addition to knowing that blastomas are coded to their anatomic sites, remember to specify laterality with blastomas in organs that are matched pairs (nephroblastoma, pleuropulmonary blastoma, and retinoblastoma). A nephroblastoma, for example, means specifying whether the blastoma is in the right kidney (C64.1), left kidney (C64.2), or an unspecified kidney (C64.3), and two codes — one for the left and one for the right organ — would be necessary if the blastoma was bilateral.