Giant Melanocytic Naevus Research Articles

Giant congenital melanocytic naevus caused by NRAS Q61K mosaicism

AbstractGiant congenital melanocytic naevi (CMN) are large melanocytic lesions commonly associated with neurologic abnormalities. Patients diagnosed with giant melanocytic naevi are at an increased risk of developing melanoma compared to patients with smaller congenital naevi. If patients develop central nervous system (CNS) lesions and exhibit certain characteristic facial features, then the diagnosis of CMN syndrome can be made. We here present the case of a 24‐year‐old female who presented with multiple melanocytic naevi, which had been apparent since birth, and was diagnosed with giant melanocytic naevi caused by NRAS Q61K mosaicism. Both close follow‐up of imaging and clinical study is important so as not to miss cutaneous malignancy and CNS lesions.

The surgical challenge of giant circumferential congenital naevi of the extremities: a 13-year follow-up of two cases

The surgical management of giant congenital melanocytic naevi involving extremities in a circumferential pattern may represent a surgical challenge with respect to their resection and subsequent reconstructive options. We present our experience in the management of circumferential giant congenital melanocytic naevi involving the upper limb in one patient and lower limb in another one. They were managed and followed up for 13 years. The lesion regenerated following dermabrasion in the first patient and regenerated following tangential excision and split-thickness skin graft in both patients. Therefore, another approach was used, full-thickness resection of the lesions and reconstruction with dermal regeneration template (Integra™), followed by ultrathin split-thickness skin graft. The last approach resulted in no recurrence during a 3-year follow-up. The complexity of these lesions and the limitation of different surgical approaches have been highlighted. Full-thickness excision of the affected integument and the use of dermal regeneration template is a useful technique which can be considered in the management of circumferential giant melanocytic naevi, particularly when other established methods have failed to provide satisfactory results.

Viewpoint 2

Viewpoint 2

Urinary excretion of 5-S-cysteinyldopa and 6-hydroxy-5-methoxyindole-2-carboxylic acid in children.

5-S-Cysteinyldopa (5SCD) and 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI2C) are formed during biosynthesis of melanins. They are used as indicators of pigment formation and markers of melanoma progression in adults and could possibly be used as markers of activity, growth and even malignant transformation in large pigmented naevi in children. We investigated the urinary excretion of these pigment precursor metabolites from 136 children, 5 to 15 years of age. The mean 5SCD excretion was 38.1 mumol/mol creatinine. A significant age-related decrease from a mean of 60.4 mumol/mol creatinine at 5 years of age to 28.0 mumol/mol creatinine at age 15 was found. In a reference group (29 adults, 20-33 years of age) the mean excretion was 48.9 mumol/mol creatinine. The mean excretion of 6H5MI2C was 42.8 mumol/mol creatinine at 5 years of age and 26.1 mumol/mol creatinine at the age of 15. The mean value for the young adults was 33.4 mumol/mol creatinine. No correlation between the mean excretion of 5SCD and 6H5MI2C was demonstrated. We suggest an upper reference level of 90 mumol/mol creatinine for the excretion of 5SCD in the age group 5-11 years and of 60 mumol/mol creatinine in the age group 13-15 years. Corresponding figures for the indole 6H5MI2C are 70 and 60 mumol/mol creatinine. The establishment of reference values in children will make it possible to use 5SCD and 6H5MI2C measurements as diagnostic tools, indicating growth or malignant transformation in giant melanocytic naevi during childhood.

(29) Giant melanocytic naevus with limb atrophy

(29) Giant melanocytic naevus with limb atrophy