Pathology/Lab Coding Alert

Question: We received multiple skin biopsies on a patient from multiple sites, labeled and identified separately. At our institution, this case would be given one accession number with multiple parts if the multiple specimens came from the same procedure/visit. Upon microscopic evaluation, one or more skin lesions turned out to be malignant (carcinoma), while others were cysts or inflammatory lesions.

What is the best ICD-9 coding for this case?

Mississippi Subscriber

Answer: The key to answering this question is your statement that the skin biopsies are labeled and separately identified according to the site of excision. As such, they are considered separate specimens for surgical pathology examination. Each specimen requires separate evaluation and diagnosis. Each should be assigned a diagnosis based on the pathologic findings.

When assigning the ICD-9 code for skin specimens, coders should be aware that this represents a large segment of the neoplasm table, taking up nearly two pages in the code book. Skin specimen diagnoses are assigned based on the location of the specimen and the neoplasm characteristics (primary or secondary malignancy, carcinoma in situ, benign, uncertain behavior, or unspecified). The first skin listing is not elsewhere classified (NEC), and then listed in alphabetical order by location from abdominal wall to wrist. For example, a basal cell carcinoma from a site on the arm is assigned 173.6, while a basal cell carcinoma from the neck is assigned 173.4.

Answered by R.M. Stainton Jr., MD, president of Doctors Anatomic Pathology Services, an independent pathology laboratory in Jonesboro, Ark.