Clinicopathological and Dermoscopic Baselines in Patients with Lynch Syndrome

Abstract

Despite the fact that Lynch Syndrome (LS) patients may also develop extra-colonic malignancies, research evaluating the association between LS and skin cancers is currently very limited. We performed a monocentric clinical and dermoscopic study involving 42 LS patients which referred to the Dermatology Unit for cutaneous screenings. In total, 22 patients showed a mutation in MLH1 and 17 patients a MSH2 mutation. Out of the entire cohort, 83% of LS patients showed brown hairs and 78% brown eyes, and the most frequent phototypes were III and II (respectively, 71.5% and 21%). A positive medical history for an internal malignancy was present in 36% of patients, with colon cancer as the most frequent malignancy in 60% of cases. A total of 853 cutaneous lesions have been analyzed: 47% of patients showed a total number of nevi > 10. The main observed dermoscopic features were a uniform reticular pattern (77% of patients), a mixed pattern (9% of patients) and a uniform dermal pattern (14% of patients). Eruptive cherry angiomas were present in 24% of cases, eruptive seborrheic keratosis in 26% and viral warts in 7% of cases; basal cell carcinoma was detected in 7% of cases. We have not found specific associations with specific skin manifestations, and the clinical and dermoscopic appearance of the pigmented lesions reflected the features present in the general population. To date, there are currently no guidelines for skin screening in LS patients. According to our study, there is insufficient evidence to ensure increased surveillance in LS patients; further studies with larger samples of patients are needed to better investigate dermatological and dermoscopic features in LS carriers.

Keywords: Lynch syndrome; MMR; cutaneous lesions; dermoscopy.

Figure 1

Cutaneous lesions observed in patients with Lynch syndrome (LS) (A). A pigmented lesion with a typical uniform reticular pattern; (B) a pigmented lesion with a mixed pattern composed of a central structureless area surrounded by a network; (C) a dermal nevus showing a uniform and unspecified dermal pattern; (D) a cherry angioma with uniform reddish pattern; (E), pigmented basal cell carcinoma and (F) uniform dermal pattern in a blue nevus.

Figure 2

Main dermoscopic features observed in the 853 analyzed cutaneous pigmented lesions (A) and other clinical cutaneous lesions observed in the sample (B).