Wiki diagnosis coding for biopsy


Mechanicsville, VA
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Patient comes in and has a biopsy I was taught in class to wait until the Path is recd back to bill with the correct dx. The physician I work for states we should bill with d48.5, Neoplasm, uncertain behavior. Which is correct and what do you do? If anyone knows where I can find it in black and white to show that would be great.
You cannot use D48.5 without a path report that indicates uncertain behavior. Look in your code book under the sub chapter heading for the D47-D48 section. I.e. Histologic confirmation of whether the neoplasm is malignant or benign cannot be made.
Histologic confirmation is a path report. You can use as a dx code the skin lesion. Look under lesion then skin and you get L98.9.
You can also use D49.2 "neoplasm of unspecified behavior." That's the more "technically correct" version of the more common "neoplasm of uncertain behavior." Both codes are used commonly for biopsies, and there is controversy about whether you need to use D49.2 rather than D48.5. The AAD says it's okay to use either one. I am not aware of any source that maintains that these codes should not be used for biopsies.
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The definition in the code book for these codes indicates that for uncertain behavior you need histologic confirmation and this a path report. For unspecified you need a preliminary dx of a tumor or new growth. It tells you the term "mass" (in quotes this means mass and other similar term like lump or lesion) is not to be regarded as a neoplasm unless otherwise documented by the provider. So for the biopsy which is a preliminary diagnostic study, you use what the provider documents as a lesion or mass.
It is in evey code book that I have looked at. Look at the sub section for neoplasm of uncertain behavior and again at neoplasm unspecified.
Neoplasm of Uncertain Behavior (D37-D48)
Note: Categories D37- D48 classify by site neoplasms of uncertain behavior, i.e. histologic confirmation whether the neoplasm is malignant or benign cannot be made.
Neoplasms of unspecified behavior (D49)
Note: Category D49 classifies by site neoplasms of unspecified morphology and behavior. The term “mass”, unless otherwise stated, is not to be regarded as a neoplastic growth.
Includes: “growth” NOS
neoplasm NOS
new growth NOS
tumor NOS
In addition coding clinics stated that you would need to a preliminary diagnostic study interpretation to use unspecified. It is unspecified because without more definitive study the provider has no way to know benign, malignant or uncertain behavior. However from the preliminary study the provider has ruled out all other possible diagnoses.
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Someone correct me if my thought are off base but I'm hoping i'm not the only one who is a little nervous about the fact there are physician that deals with skin cancer who don't know the difference between, Benign, Malignant and Uncertain behavior?
No physician would know based on sight whether an abnormality is benign, malignant or uncertain behavior. It always take a histologic study via microscope to know the difference.
Apologies and I agree. Although it may be due to misunderstanding of the code for uncertain behavior. Some coders as well as physicians have mistakenly interpret this to mean that the provider is uncertain as to what they are looking at. They do not realize that these codes were created to indicate patient diagnosis, not provider thoughts.
Which code is correct

So just to clarify when we bill a 11100 we should use D48.2 and not the D48.5? Thanks in advance
We will get the path report back but for the biopsy DOS we have been using D48.5 but are wondering if we should be using D49.2 instead.
if you are billing for the biopsy you must either bill the dx from the path report or use the L code for the skin lesion. without the path you do not have the diagnosis for the D48 code and without a preliminary study you will not have the documentation to support the D49. it is a skin lesion and that is what you can code.
If the biopsy is done on a lesion, then D49.2 is appropriate, since lesions are neoplasms and this is explicitly what the D49 section is to be used for.

The only time you would need to use a code from the L series (or wait for path, if you prefer) is if the biopsy is being done on something other than a lesion, such as a rash.