Pathology/Lab Coding Alert

Watch out for DSAP ICD-9 trap.

Your pathologist receives two skin specimens from the same patient on the same day — a lesion from the patient’s right ankle and one from the patient’s neck. That sounds like a case with simple enough coding, but read on to see what trials await you as you zero in on the proper diagnosis and procedure codes.

Highlight Diagnosis First

CPT® provides several pathology procedure codes for skin evaluation depending on the type of skin specimen. That’s why you need to focus on the diagnosis first, as you code the case.

Specimen 1: The pathologist receives a specimen from the patient’s right ankle that the surgeon describes as a “1.3 cm circular lesion that appears hyperkeratotic, possibly a wart or actinic keratosis.” Upon microscopic examination, the pathologist identifies a classic cornoid lamella, which is a thin vertical column of parakeratosis in the epidermal stratum corneum that makes up an outer “ring” of the lesion.

Dx: The pathologist’s findings point to a porokeratotic lesion. The surgeon’s initial mis-diagnosis in this case is not unusual. Physicians “may confuse [porokeratosis] with warts or with ‘seed corns,’ or might refer to the lesions as ‘IPKs’ (intractable plantar keratosis), but they’re not really the same thing,” says Arnold Beresh, DPM, CPC, of Peninsula Foot and Ankle Specialists PLC in Hampton, Va.

That means you should not code a wart (078.1, Viral warts) or actinic keratosis (702.0, Actinic keratosis), even though that’s what the surgeon reported. Instead, you should code the final diagnosis from the pathology report.

Problem: No specific ICD-9 exists for porokeratotic lesions, but you can safely report 701.1 (Keratoderma, acquired) for the condition. This case involves an isolated lesion, so don’t make the mistake of reporting 692.75 (Disseminated superficial actinic porokeratosis [DSAP]) as the diagnosis. Although DSAP is a form of porokeratosis, it is a specific condition typified by a large number of lesions scattered about sun-exposed limbs.

Specimen 2: The pathologist receives excised tissue from the patient’s scalp that the op report identifies as a “possible pilar cyst.” The pathologist determines that the cyst is a true sebaceous cyst (steatocytoma) containing sebaceous glands and filled with sebum.

For ICD-9 code assignment, you should choose 706.2 (Sebaceous cyst). Remember that the surgeon identified the tissue as a possible pilar cyst, which is a cyst originating from hair follicles and containing keratin rather than sebum. “ICD-9 provides a distinct code for this condition: 704.41 (Pilar cyst), so you need to be sure that you code based on the documentation,” says Pamela Biffle, CPC, CPC-P, CPC-I, CHCC, CHCO, owner of PB Healthcare Consulting and Education Inc. in Austin, Texas.

Remember: you should code from the final diagnosis in the pathology report, not from the possible diagnosis given in the op report.

Choose Procedure Code by Skin Type

Once you’ve identified the diagnosis codes so that you know the type of specimen you’re dealing with, you can accurately assign the procedure code to describe the pathologist’s work.

CPT® provides only the following three codes to describe skin-specimen pathology services:

• 88302 — Level II - Surgical pathology, gross and microscopic examination, skin, plastic repair
• 88304 — Level III - Surgical pathology, gross and microscopic examination, skin - cyst/tag/debridement
• 88305 — Level IV - Surgical pathology, gross and microscopic examination, skin, other than cyst/tag/debridement/plastic repair.

“You should choose one of these three codes for any skin specimen, regardless of specimen size, depth, or neoplastic status,” says R.M. Stainton Jr., MD, president of Doctors’ Anatomic Pathology Services in Jonesboro, Ark.

Distinguish the three codes by determining if the skin specimen is:

• removed during plastic repair
• a cyst, or skin tag, or skin from debridement
• any other skin specimen.

If the operative note indicates that the surgeon removed a skin specimen and the pathologist’s findings indicate normal skin or abnormalities that originate in the skin, you’ll need to turn to these codes.

The case: For the pathologist’s examination of the porokeratotic lesion, you should report 88305. Even if the specimen exhibited neoplastic changes, as these lesions sometimes do, you should stick with 88305.

For the sebaceous cyst, you should report 88304. Although ICD-9 coding is different for a sebaceous cyst versus a pilar cyst, the diagnosis is a distinction without a difference for selecting the CPT® code, because you should select 88304 for all skin cyst specimens.

Code per specimen: Because the “specimen” is the unit of service for surgical pathology codes, you’re justified in reporting a distinct procedure code for each of the two skin specimens in the case.