Purpose: Two-millimeter punch biopsy is a swift and practical diagnostic tool in the outpatient setting. However, few studies have evaluated the efficacy of the method for diagnosis of malignant eyelid tumors.
Methods: This was an observational study of patients with suspicion of malignant eyelid tumor attending the Ocular Plastic Surgery Center at Hospital das Clínicas, University of São Paulo School of Medicine. Following standard procedures, preoperative biopsies were taken with a 2-mm trephine and surgical excision was performed with safety margins, followed by reconstruction. Anatomopathologic analysis of the surgical specimen was used as gold standard to evaluate the accuracy of diagnosis by punch biopsy.
Results: The study included 50 periocular tumors with suspicion of malignancy. The indicators of efficacy in the identification of malignancy by 2-mm punch biopsy were: sensitivity 88%, specificity 100%, positive predictive value 100%, and negative predictive value 64%. Accuracy was 90% for malignancy and 80% for histologic type. The κ index of agreement between the diagnostic methods was 0.722 (p < 0.001).
Conclusion: A positive result with 2-mm punch biopsy is a safe indication for surgical excision of the tumor, whereas a negative result does not necessarily imply benignity. In cases of high clinical suspicion, a second biopsy should be taken from a different part of the tumor to rule out malignancy.