I was told to add them together when I did derm clinic but I did find this so I hope it helps you!
The code selection depends on the reason for removal. Removal of a lesion by shaving, codes 11300â€“11313 (differentiated by body area and lesion diameter), may be reported for lesions that require only superficial removal, such as a benign-appearing nevus on a body area subject to trauma. Biopsy codes 11100â€“11101 should be reported when the intent is to obtain tissue to send to pathology (e.g., biopsy of a suspicious lesion using shave technique). Codes for excision of benign lesions (e.g., 11400â€“11471) or malignant lesions (e.g., 11600â€“11646) should be reported for full-thickness removal (through the dermis), including margins.
To get the correct number, I found this example. To determine the total excised diameter, calculate the lesion diameter at its widest point (the crucial measurement under the old guidelines) plus the width of the margin at its narrowest point.
For example, the surgeon excises an irregularly shaped, malignant lesion from a patientâ€™s left shoulder. The lesion measures 1.5 cm at its widest. To ensure removal of all malignancy, the surgeon allows a margin of at least 1.5 cm on all sides. In this case, add the size of the lesion (1.5 cm) and the width of the narrowest margin (1.5 cm top, 1.5 cm bottom) for a total of 4.5 cm (1.5 + 1.5 + 1.5 = 4.5). Therefore, the appropriate code is 11606 (Excision, malignant lesion including margins, trunk, arms, or legs; excised diameter over 4.0 cm).
Brooke Bierman, CPC, CPB
Coding & Billing Manager
2014 President AAPC Des Moines Chapter