Accuracy in clinically evaluating pigmented lesions.

Abstract

OBJECTIVE: To determine the ability of three doctors experienced in managing melanocytic lesions to diagnose correctly melanoma, dysplastic naevi, and various benign pigmented lesions. DESIGN: Independent clinical evaluation and histopathological assessment. SETTING: Pigmented lesion clinic, which patients attend without an appointment for early diagnosis of melanoma. PATIENTS: 86 Patients with lesions that were judged to be benign by at least one of the three doctors. INTERVENTIONS: The lesions were excised under local anaesthesia and sent for histopathological examination in coded bottles without clinical details. MAIN OUTCOME MEASURE: Comparison of clinical with histopathological diagnosis for each lesion. RESULTS: A total of 120 lesions were evaluated by at least two of the three doctors. The histopathological diagnoses were made by the same pathologist. The overall sensitivity (diagnostic accuracy) for the three doctors for all types of lesion was 50%. Of the 39 dysplastic naevi, only 19 were identified correctly by all observers, and a further 24 banal lesions were wrongly diagnosed as dysplastic by at least one doctor. Particular difficulty was experienced with small (less than 5 mm), flat lesions, which can be banal or potentially malignant. CONCLUSIONS: Critical diagnosis and management decisions concerning pigmented lesions should always be based on a combination of clinical and histopathological assessments and the history of the patient.