Incidence of different types of cancer in the follow-up period after primary diagnosis and treatment of melanoma. Single-centre 4-year follow-up on a population of 709 patients

INTRODUCTION: Follow-up plays a key role in melanoma management, especially in the first years after diagnosis. During this period it is crucial to assess possible recurrence, progression of the disease or treatment complications. An important aspect is also the possibility of formation of new primary foci or other skin cancers. AIM: To assess the coincidence of skin lesions and cancers among the melanoma patients. MATERIAL AND METHODS: Patients treated in the Comprehensive Cancer Centre between 2019 and 2022 were retrospectively analysed for occurrence of skin lesions diagnosed during the follow-up, and confirmed by biopsy. The lesions considered included skin cancers, dysplastic nevus and actinic keratosis. RESULTS: In 100 (14%) out of 709 enrolled patients, 184 lesions were diagnosed. In 7 patients it was melanoma, in 49 BCC, and in 16 SCC. Dysplastic nevus and actinic keratosis were excised in 28 and 14 patients, respectively. More than one site of the skin lesion was observed in 39 patients, and more than one type of the lesion in 13 patients. Patients with lesions were on average 8.6 years older (p < 0.001), had less advanced tumours (p = 0.010), and primary melanoma was more often located on the head and neck (p = 0.056). CONCLUSIONS: Among melanoma patients, particular attention must be paid to, apart from early detection of melanoma recurrence and progression, the occurrence of new primary foci or independent skin cancers.