BACKGROUND: A series of studies has investigated epidemiological, clinical and genetic characteristics of patients with multiple primary melanoma (MPM). However, comparison of the clinical and dermoscopic features of MPM within a given individual has been described only in case reports. OBJECTIVES: To describe the dermoscopic features of MPM for each given patient, and to evaluate the characteristics eventually associated with similar or dissimilar appearance. METHODS: From the databases of three skin-lesion clinics in the U.S.A., Italy and Spain we collected the dermoscopic images of melanomas in patients diagnosed with MPM. RESULTS: Among 58 patients with MPM, we found that 53% of patients had dermoscopically similar melanomas and 47% of patients had dermoscopically different melanomas. In older patients 59% of melanomas were dermoscopically similar vs. 47% in younger patients (P=0·377). Similar thickness was associated with the occurrence of dermoscopically similar melanomas (19/30 cases, 63%; P=0·039). Most (65%) of the synchronous lesions were similar, compared with 36% of nonsynchronous lesions (P=0·029), and most (69%) of the melanomas on sun-damaged skin were similar, vs. 37% of melanomas on nonsun-damaged skin (P=0·015; odds ratio 3·88, 95% confidence interval 1·11-13·98). The percentage of dermoscopically different melanomas was higher in patients with a family history of melanoma (67% vs. 48%). CONCLUSIONS: MPMs in a given patient have almost the same chance of looking dermoscopically similar or different. However, a subset of elderly patients with sun-damaged skin may present multiple, similar, thin melanomas characterized by pigment-network and regression structures.
BACKGROUND: A series of studies has investigated epidemiological, clinical and genetic characteristics of patients with multiple primary melanoma (MPM). However, comparison of the clinical and dermoscopic features of MPM within a given individual has been described only in case reports. OBJECTIVES: To describe the dermoscopic features of MPM for each given patient, and to evaluate the characteristics eventually associated with similar or dissimilar appearance. METHODS: From the databases of three skin-lesion clinics in the U.S.A., Italy and Spain we collected the dermoscopic images of melanomas in patients diagnosed with MPM. RESULTS: Among 58 patients with MPM, we found that 53% of patients had dermoscopically similar melanomas and 47% of patients had dermoscopically different melanomas. In older patients 59% of melanomas were dermoscopically similar vs. 47% in younger patients (P=0·377). Similar thickness was associated with the occurrence of dermoscopically similar melanomas (19/30 cases, 63%; P=0·039). Most (65%) of the synchronous lesions were similar, compared with 36% of nonsynchronous lesions (P=0·029), and most (69%) of the melanomas on sun-damaged skin were similar, vs. 37% of melanomas on nonsun-damaged skin (P=0·015; odds ratio 3·88, 95% confidence interval 1·11-13·98). The percentage of dermoscopically different melanomas was higher in patients with a family history of melanoma (67% vs. 48%). CONCLUSIONS: MPMs in a given patient have almost the same chance of looking dermoscopically similar or different. However, a subset of elderly patients with sun-damaged skin may present multiple, similar, thin melanomas characterized by pigment-network and regression structures.
Authors: Daniel Coelho de Sá; Juliana Abreu Pinheiro; Emmanuel Pereira Benevides Magalhães; Maria Araci de Andrade Pontes Journal: An Bras Dermatol Date: 2022-07-07 Impact factor: 2.113