Nevus Lipomatosus Cutaneous Superficialis Mimicking Atrophoderma: An Interesting Case

Dear Editor, A 29-year-old male presented to the outpatient department of dermatology department with complaints of asymptomatic skin-colored raised lesions since 3 years on the lower back. These lesions were insidious in onset and started as pea-sized lesions, slowly progressed and coalesced to form the present-size lesions. There was no history of pain or bleeding from the lesions. Clinical examination of the lesion revealed multiple, soft, skin-colored plaques (size 1 cm × 2 cm) and nodules on the left side of lower back in segmental distribution [Figures 1 and 2]. The surface of the lesion was cerebriform and atrophied. Regional lymphadenopathy was absent. Routine laboratory investigations were within normal limits. We considered differential diagnosis of atrophoderma of Moulin, nevus lipomatosus cutaneous superficialis (NLCS), focal dermal hypoplasia. Histopathologic examination revealed the presence of keratinized stratified squamous epithelium. The dermis showed lobules of mature fat [Figure 3]. Histopathologic findings confirmed our diagnosis of NLCS. The patient was managed conservatively and counseled about the benign nature of the condition.Figure 1: Multiple, soft, skin-colored plaques on the lower back of patient in segmental distributionFigure 2: Magnified view of the multiple skin-colored plaques on back of patientFigure 3: Histopathologic section shows the presence of adipocyte clusters in the dermis (H and E, ×50)NLCS is a rare connective tissue hamartoma of unknown etiology marked by ectopic presence of adipocytes in the dermis. Theories postulated regarding its etiopathogenesis suggest development of classical type of NLCS as a result of degenerative changes in the dermal connective tissue and adipose metaplasia, or due to differentiation of mononuclear cells into lipoblasts and further mature adipocytes, or due to developmental displacement of adipocytes.[1] It can present in two clinical patterns, namely classical and solitary form. The former type is mostly congenital but may develop later during the first few decades of life. These present as multiple skin-colored or yellowish papules, coalescing into plaques with smooth or cerebriform surface, and have insidious onset. The lesions are arranged in linear, segmental or zosteriform distribution and commonly involve lower trunk, gluteal region, pelvic girdle and thigh. The later form of NLCS usually presents as solitary papule or nodule, with late onset, during third to sixth decades of life. It has no predilection for site.[2] Both the forms are mostly asymptomatic but rarely ulceration can occur in some cases. In few cases reports, hypopigmented spots, café-au-lait macules, hypertrichosis and comedo-like lesions have been associated with the NLCS.[3] NLCS should be differentiated from the clinical mimickers like atrophoderma, focal dermal hypoplasia, neurofibroma and connective tissue nevus. Histopathology is required for the differentiation. On microscopy, NLCS is characterized by the presence of mature fat cells embedded among the collagen bundles in the reticular dermis in solitary form of NLCS (both reticular and papillary dermis in classical type). Atrophoderma of Moulin usually presents as hyperpigmented, slightly atrophic, unilateral lesions following Blaschko lines on the trunk or limbs. Histopathologic examination of atrophoderma shows hyperpigmentation of the basal epidermis and a normal dermis with unaltered connective tissue and elastic fibers.[4] Focal dermal hypoplasia presents as linear depressed lesions or soft, red-yellowish outpouchings of skin, typically involving thighs, buttocks and trunk, and histopathology demonstrates hypoplasia of dermis with telangiectasia, along with resultant upward extension of the subcutis tissue.[5] Treatment of NLCS mainly comprises of surgical excision due to cosmetic concerns of the patient or due to risk of ulceration in large lesions. Our case was interesting because of the presence of atrophy in some plaques which mimicked atrophoderma; however, classical histopathologic findings confirmed our diagnosis of NLCS. We report this case to highlight the atypical presentation of a rare connective tissue nevus. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.