General Surgery Coding Alert

For 2003, CPT significantly revises its guidelines for reporting excision of benign (11400-11471) and malignant (11600-11646) lesions, and now specifies that physicians should include margins in addition to lesion diameter when choosing an appropriate code. For the greatest accuracy, physicians and coders must also consider the timing of measurements and excisions, and apply modifiers as necessary. How Do You Measure Up? Because 11400-11471 and 11600-11646 are "size-based" codes (for example, 11400, Excision, benign lesion including margins, except skin tag [unless listed elsewhere], trunk, arms or legs; excised diameter 0.5 cm or less; versus 11404 ... excised diameter 3.1 to 4.0 cm), properly determining the diameter of the area excised is of primary importance when reporting lesion excision. Unlike previous years, CPT 2003 instructs physicians to include the margins the normal-appearing tissue around the lesion that the surgeon excises to ensure complete removal of any biological extension of the tumor when measuring the excised diameter. The distinction is important. Many physicians and coders, familiar with the "old" CPT guidelines, may inadvertently or absentmindedly continue to choose excision codes based on lesion diameter only, but this will almost always lead to an incorrect code under the new guidelines. 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, says Allan Wirtzer, MD, a dermatologist in private practice at Mid-Valley Dermatology in Sherman Oaks, Calif., who helped develop the codes as the American Academy of Dermatology's representative to the CPT Advisory Committee. For example, the surgeon excises an irregularly shaped, malignant lesion (see Figure 1, right) from a patient'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). Timing Is Everything Just as important as determining the diameter of excision correctly is taking the measurement at the appropriate time: that is, prior to excision. The pathology report will not provide an accurate measurement because lesions shrink when placed in formaldehyde, says Kathy Pride, CPC, CCS-P, HIM applications specialist with QuadraMed based in San Rafael, Calif. Relying on the pathology report will mean smaller measurements and a consequent loss in legitimate compensation.

Timing also plays a crucial role in subsequent excisions if a frozen-section pathology shows [...]