Criteria for Evaluation of Modern Methods of Diagnostics of Melanocytic Skin Neoplasms with the Use of the Number Needed to Biopsy
Introduction. Melanoma incidence, one of the aggressive skin tumors, has increased in recent decades all over the world. Due to possible overdiagnosis and the sharply increased number of biopsies, the term Number Needed to Biopsy, NNB, is widely used by foreign researchers. This index can help to determine the competence of a specialist and medical institution. Material and methods. A retrospective study of electronic primary documentation of249 patients with a directing diagnosis for a biopsy of Clark’s nevus, or dysplastic nevus, with ICD-10 code Z-03.1 and D22 was carried out for the period 2018-19. The number needed to biopsy was calculated as the number of biopsied lesions divided by histologically-proven melanoma. Results. 62 patients were diagnosed with melanoma. The median of the tumor Breslow thickness was 0.8 [0.5; 1.5] mm - in 2018 and 0.4 [0.28; 0.69] mm - in 2019, p (Mann-Whitney U-test) = 0.00046. The number needed to biopsy for 2018-19 was 4.0. Conclusion. The number needed to biopsy is recommended for dynamic comparison of the effectiveness of clinic work, but if fixed calculation criteria will be used.