Selective use of sequential digital dermoscopy imaging allows a cost reduction in the melanoma detection process: a belgian study of patients with a single or a small number of atypical nevi

Abstract

Background: Dermoscopy is a technique which improves melanoma detection. Optical dermoscopy uses a handheld optical device to observe the skin lesions without recording the images. Sequential digital dermoscopy imaging (SDDI) allows storage of the pictures and their comparison over time. Few studies have compared optical dermoscopy and SDDI from an economic perspective.

Objective: The present observational study focused on patients with one-to-three atypical melanocytic lesions, i.e. lesions considered as suspicious by optical dermoscopy. It aimed to calculate the "extra-costs" related to the process of melanoma detection. These extra-costs were defined as the costs of excision and pathology of benign lesions and/or the costs of follow-up by SDDI. The objective was to compare these extra-costs when using optical dermoscopy exclusively versus optical dermoscopy with selective use of SDDI.

Methods: In a first group of patients, dermatologists were adequately trained in optical dermoscopy but worked without access to SDDI. They excised all suspicious lesions to rule out melanoma. In a second group, the dermatologists were trained in optical and digital dermoscopy. They had the opportunity of choosing between immediate excision or follow-up by SDDI (with delayed excision if significant change was observed). The comparison of extra-costs in both groups was made possible by a decision tree model and by the division of the extra-costs by the number of melanomas diagnosed in each group. Belgian official tariffs and charges were used.

Results: The extra-costs in the first and in the second group were respectively €1,613 and €1,052 per melanoma excised. The difference was statistically significant.

Conclusions: Using the Belgian official tariffs and charges, we demonstrated that the selective use of SDDI for patients with one-to-three atypical melanocytic lesions resulted in a significant cost reduction.

Figure 1. Study flowchart.

The evolution of the patients is divided into two groups. In Group 1, patients were examined by dermatologists adequately trained in optical dermoscopy (OD). In Group 2, patients were examined by dermatologists adequately trained in optical dermoscopy and who had access to sequential digital dermoscopy imaging (SDDI).

Figure 2. Observed total direct extra-costs distributed in the decision-tree model.

This figure shows the observed total direct extra-costs distributed in a decision tree model. In Group 1, patients were examined by dermatologists adequately trained in optical dermoscopy (OD). In Group 2, patients were examined by dermatologists adequately trained in optical dermoscopy and who had access to sequential digital dermoscopy imaging (SDDI). *Melanoma excision costs are not taken into account because these should be the same for each correctly diagnosed melanoma, irrespective of which group they belonged to.

Figure 3. Histogram of the estimated extra costs of sequential digital dermoscopy imaging versus optical dermoscopy.

The extra-costs are defined as the costs of excision and pathology of benign lesions and/or the costs of follow-up by sequential digital dermoscopy imaging. These extra-costs are divided by the number of melanomas diagnosed in each group.

Figure 4. Sensitivity analysis: tornado graph.

Mela OD: number of excised melanomas in the optical dermoscopy (OD) group; Mela SDDI: number of excised melanomas in the sequential digital dermoscopy imaging (SDDI) group; P unnec ex OD: number of patients with unnecessary excisions in OD group; P unnec ex SDDI: number of patients with unnecessary excisions in SDDI group; P ctrl T0: number of patients registered by SDDI at inclusion time; P ctrl 12 M: proportion of patients followed-up by SDDI at 12 months; N unnec ex: average number of unnecessary excisions per patient; Multi unnec ex: proportion of patients with >1 unnecessary excision.