Pathology review of cases presenting to a multidisciplinary pigmented lesion clinic

To determine if pathology review, within the context of a multidisciplinary pigmented lesion clinic, results in changes in diagnosis of melanocytic lesions and to ascertain if the change in diagnosis altered clinical management and outcome.

Retrospective review of pathology reports, progress notes, and diagnoses entered in the University of Pennsylvania (Philadelphia) Pigmented Lesion Clinic database.

A total of 5136 primary melanocytic lesions from patients referred to the pigmented lesion clinic between 1991 and 1999 were reviewed by a single pathologist. Of these, 559 (11%) had diagnoses that were changed significantly from the submitting diagnosis, with 120 (2.3%) undergoing a "critical" revision, 63 (1.2%) defined as a change from malignant to benign, and 57 (1.1%) from benign to malignant; 171 (3.3%) remained within the same category (benign or malignant) but had a downgrade in diagnosis (less severe) that would have a significant impact on treatment, prognosis, and research. Likewise, 268 (5.2%) remained within the same category but had an upgrade in diagnosis (more severe) that would have a significant impact on the same parameters. In addition, 257 reexcisions of melanocytic lesions were reviewed, of which 15 (5.8%) were changed from clear to involved margins, while another 16 (6.2%) were changed from involved to clear margins, for a total of 12%. Of the lesions with a critical revision, follow-up was obtained in 98 (83%). The patients in the malignant-to-benign category were followed up for an average of 2.6 years while those in the benign-to-malignant category were followed up for an average of 4.2 years. The change of diagnosis from malignant to benign resulted in 9 patients (17%) being spared a reexcision while 12 patients (23%) were downgraded from a radical to moderate reexcision. The change in diagnosis from benign to malignant resulted in 45 patients (98%) requiring a reexcision after review. Twenty-five of these patients were found to have residual disease in their reexcision specimens or had already had recurrence at the excision site. Furthermore, 7 patients (15%) underwent lymph node dissection or sentinel lymph node biopsy after review. However, none of the nodes were positive for metastatic disease. During this time, 8 patients (17%) in the benign-to-malignant category, and 1 patient (1.9%) in the malignant-to-benign category (who had previously had 4 primary melanomas) developed metastatic disease.

Pathology review of primary melanocytic lesions, within the context of a multidisciplinary pigmented lesion clinic, results in changes in diagnosis in a significant proportion of cases. These changes have important implications for clinical decision making, patient outcome, and research data collection.