Primary Care Coding Alert

Some family physician (FP) coders may look at a report containing excision and start hunting for a lesion excision code. But before you enter those five digits, make sure you're in the right category.

First, reviewing the skin's anatomy will help you navigate CPT's integumentary section (10040-19499). These codes reflect the skin's three main layers: the epidermis, dermis and subcutaneous tissue. The epidermis, the outer skin layer visible to the naked eye, protects the deeper layers from injury and foreign substances. Corns, calluses and cancers, including basal cell carcinoma, squamous cell carcinoma and melanomas, originate in the epidermis.

The second layer of skin, the dermis, lies underneath the epidermis. The dermis'structural components include collagen, elastin and ground substance that give support and elasticity to the skin. In addition, the dermis contains blood and lymphatic vessels, nerves and nerve endings, sebaceous (oil-producing) glands and sweat glands, and hair follicles.

The integument's third and deepest layer, subcutaneous tissue, includes fat cells, nerves and blood vessels. The subcutaneous tissue serves three purposes: It insulates the body from cold, absorbs trauma and cushions deeper tissues, and stores the body's reserve fuel.

Now that you know the basic layers, use that knowledge to ensure that the FP excised a lesion. Some CPT definitions may differ from your physicians'use. CPT defines lesion excision as a "full-thickness" cut (through the dermis), says Joy Newby, LPN, CPC, president of Joy Newby & Associates Inc., a reimbursement consulting company in Indianapolis. So to report an excision, the doctor must cut through the epidermis and the dermis, the second skin level. Do not jump to the conclusion that the FP performed a lesion excision unless the operative report indicates a full-thickness cut. Encourage your doctors to use this terminology.

In addition, a lesion that requires excision includes simple closure. Therefore, documentation should reflect some form of closure, such as sutures or tissue adhesive. Check with your doctor if the operative report does not mention one of these types, because he may have performed a biopsy rather than an excision. Deeper lesions may require intermediate or complex closure, which you should report separately.

Armed with the basics, you may think that you can proceed with finding the correct code. But before billing a lesion excision code, you must check one final item: medical necessity. Medicare and most payers will cover excisions that they deem medically necessary. "Most insurers do not cover lesions removed for cosmetic purposes," Newby says. "Thus, the physician should document the medical necessity of performing the excision."

If the lesion is asymptomatic and clearly benign like a skin tag or normal mole, insurers may consider the care unnecessary. For example, a patient with a mole on her lip wants to have it removed even though it has not changed for years in color or size and presents no danger to the patient. Most likely, the payer will deem the procedure unnecessary.

On the other hand, a carrier may consider it necessary to remove a lesion that constantly bleeds when aggravated, such as from shaving or rubbing from a clothing line. Before billing, you should check carriers'policies regarding medical necessity.