Internal Medicine Coding Alert

Published on Sun May 09, 2010 PDF

Learn why preempting 11600 could send $55 down the drain.

Pathology tests aren't there for nothing. The internist sends the excised lesion to the lab in order to provide her an exact reading of what type the lesion is, and how it is behaving (whether benign or malignant). Only the pathologist can decide on lesion pathology -- allow him that privilege.

Caution: In no way you -- as coder -- should choose the pathology of a lesion based on the operative notes alone. Wait, wait, wait for the lab results.

Get Hints from the Pathology Report

Scenario 1: Your internist removes a 2-mm suspicious skin lesion from a patient's back using a 1-mm margin. What choice of codes do you have?

Solution 1: You could choose between 11400 (Excision, benign lesion including margins, except skin tag [unless listed elsewhere], trunk, arms or legs; excised diameter 0.5 cm or less) or 11600 (Excision, malignant lesion including margins, trunk, arms or legs; excised diameter 0.5 cm or less). But wait until you hear from the lab since there's no such thing as "suspicious" lesion code. The lab report will confirm the type of lesion removed from the patient, but until then you'll never know whether the lesion is benign or malignant.

Careful: Turning in 11400 when it should be the malignant excision code could take away as much as $62 from your reimbursement. CPT 11400 pays about $109.51 (2.97 RVU), while you should get about $171.09 from 11600 (4.64 RVU), based on a conversion factor of $36.8729. Besides the issue of accuracy, it is also unethical to go ahead without the pathology report, says Linda Martien, CPC, CPC-H, coding specialist with National Healing in Boca Raton, Florida.

Don't Be Swayed by 'Uncertain' Physician Notes

Scenario 2: You read your internist's documentation as follows: "I removed one approximately 9-mm lesion from the patient's wrist using surgical curettage. Lesion had a red outer crust and an irregular border, but it looked dissimilar from the patient's actinic keratosis spots on her face, so I am uncertain of the lesion's status. Sent lesion to the lab and will await results." What ICD-9 should you report?

Be careful: If you think 238.2 (Neoplasm of uncertain behavior of other and unspecified sites and tissues; skin) is the proper ICD-9 to describe the lesion, you're wrong. You can only report 238.2 "if the pathologist who examines the sample states that the lesion exhibits uncertain behavior, not when the physician thinks it might be," says Chris Felthauser, CPC, CPC-H, ACS-OH, ACS-OR, PMCC, medical coding instructor for Orion Medical Services in Eugene, Oregon.

Tip: The histopathology holds the key in establishing the correct ICD-9 code, not the physician's opinion. You don't want to mislabel a patient with malignant cancer when the lesion is actually benign. Your claim will be headed for a denial if your ICD-9 code doesn't support the lesion type that the CPT code represents.

Solution 2: For your ICD-9 code, check the pathology report. If it comes back with a malignant neoplasm diagnosis that the internist indicates is a primary malignancy, you would report the site specific neoplasm code: 173.6 (Other malignant neoplasm of skin; skin of upper limb, including shoulder). For a pathology report that determines the neoplasm is benign, you would use 216.6 (Benign neoplasm of skin; skin of upper limb, including shoulder).

"Make sure there is documentation as to why the internist chose to remove the lesion," adds Felthauser. Why? Mostcarriers do not cover 'cosmetic' removals of benign skin neoplasms. Better yet, send the documentation along with the claim to support the fact that the removal was not for cosmetic reasons.

Figure the Lesion's Diameter Before Lab Tests

Scenario 3: The internist excises an irregularly shaped, malignant lesion -- as the pathology report later determines -- from just below the patient's right shoulder. The lesion measures 2 cm at its widest point. The physician allows a margin of at least 1.5 cm on all sides to remove all malignant tissues. What should you report?

Solution 3: In this case, you should report 11606 (Excision, malignant lesion including margins, trunk, arms, or legs; excised diameter over 4.0 cm), but not until you document the measurement of the lesion's diameter at its widest point and add to that measurement twice the width of the narrowest margin. The total measurement is 5 cm (2 cm + [1.5 cm x 2]).

Purpose: Documenting the size of the lesion excision before removing it and sending it to pathology for analysis is a must because the lesion gets smaller after the first incision. It usually shrinks further when preserved in formaldehyde.

Warning: Do not confuse the actual size of the lesion with the length of surgical incision. It is but logical for the internist to make an incision longer than the lesion. Still, keep in mind that they are two different things -- with two different measurements.