Table 5.
Characteristics of False-Positive Cases of Nonmelanoma Skin Cancer Identified in 2007 HMO Health Plan Enrollee Claims Data, by Identification Method, Henry Ford Health System, Detroit, Michigan
| Noncase Reason | ICD-9-CM Alone (n = 25) |
CPT Alone (n = 4) |
Both ICD-9-CM and CPT Codes (n = 14) |
|||
| No. | % | No. | % | No. | % | |
| Atypical melanocytic lesion incorrectly labeled as NMSC (including atypical nevus, blue nevus, melanoma, melanoma in situ) | 1 | 4 | 4 | 100 | 1 | 7 |
| Benign lesion incorrectly labeled with a malignancy code, other than melanocytic | 2 | 8 | 0 | 2 | 14 | |
| Malignancy other than melanoma with its own unique ICD-9-CM code (including mycosis fungoides, vulvar intraepithelial neoplasia, angiosarcoma) | 1 | 4 | 0 | 2 | 14 | |
| Surgical defect repair linked to neoplasm (i.e., repair by plastic surgery after Mohs chemosurgery) | 2 | 8 | 0 | 0 | ||
| Lesion diagnosed visually (without confirmed biopsy/no histopathologic confirmation) and referred for malignant lesion excision | 7 | 28 | 0 | 9 | 64 | |
| New diagnosis discussed/preoperative visit | 2 | 8 | 0 | 0 | ||
| Follow-up or postoperative visit/history of NMSC | 10 | 40 | 0 | 0 | ||
Abbreviations: CPT, Current Procedural Terminology; HMO, health maintenance organization; ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification; NMSC, nonmelanoma skin cancer.