Giant congenital melanocytic nevus associated with lipoma in an Indian man

Congenital melanocytic nevus (CMN) is a melanocytic proliferation that has its onset at birth or shortly thereafter and shows characteristic histopathologic features including symmetric proliferation of benign melanocytes, extension of nevus cells into the deep reticular dermis and subcutis, maturation of melanocytes with descent, tracking of melanocytes around and within adnexal structures, vessels, or nerves and splaying of collagen bundles by nevus cells arranged in single rows or cords. We report the case of a 34year old previously healthy woman who presented with a progressively enlarging soft tissue mass in the right neck and back adjacent to a medium sized CMN. Magnetic resonance imaging showed multiple lipomatous masses within the soft tissues of the posterior superficial neck. Subsequent excision of the soft tissue mass showed a well circumscribed lipomatous lesion with diffuse infiltration by benign appearing melanocytes within the fat lobules. Excision of the mass was not accompanied by overlying skin and, thus, posed a diagnostic challenge. Sudden increase in the size of a CMN is worrisome for the development of a melanoma, however, this lesion lacked significant cytologic atypia and mitotic figures, and had a low proliferative index by Ki-67 immunohistochemistry. This case serves to illustrate the initial diagnostic dilemma as well as the plasticity of the neural crest cells.

Congenital melanocytic nevi are melanocytic nevi that have their onset at birth or during the first 2 years of life. They are relatively common with an incidence among newborns ranging between 0.2% and 6% (Zayour and Lazova R, Clin Lab Med 31:267–280, 2011). There is a female predominance. Congenital melanocytic nevi initially present as pigmented macules or slightly raised oval papules or plaques. They usually darken over time and become raised or verrucous. Congenital melanocytic can display a wide variety of colors ranging from light brown to black. Hypertrichosis is commonly observed. Congenital melanocytic nevi usually grows proportionally with the child. They are classified according to their estimated adult size as small (<1.5 cm), medium (1.5–20 cm), large or giant (>20 cm) (Navarro-Fernandez and Mahabal, Congenital nevus, 2020). Giant nevi occasionally show satellite smaller lesions. Congenital melanocytic nevi may be associated with melanocyte proliferation in the central nervous system. Large lesions have a higher risk of melanoma development. Congenital melanocytic nevi are usually diagnosed based on the clinical appearance. Dermoscopy or punch biopsy for histopathological examination may be used in cases of diagnostic doubt. Treatment options may be divided into surgical and non-surgical. Non-surgical therapeutic options include dermal abrasion, chemical peels, cryotherapy, electrosurgery, and ablative lasers.KeywordsCongenital melanocytic nevusDermoscopyMelanocyteMelanomaNeviScalp

NRAS Mutation Is the Sole Recurrent Somatic Mutation in Large Congenital Melanocytic Nevi

Introduction: High-intensity focused ultrasound (HIFU) and radiofrequency (RF) are used for non-invasive skin tightening. Neocollagenesis and neoelastogenesis have been reported to have a mechanism of controlled thermal injury. Objective: To compare neocollagenesis and neoelastogenesis in each layer of the dermis after each session of HIFU and monopolar RF. Methods: We analyzed the area fraction of collagen and elastic fibers using the Masson's Trichrome and Victoria blue special stains, respectively, before and after 2 months of treatments. Histometric analyses were performed in each layer of the dermis, including the papillary dermis, and upper, mid, and deep reticular dermis. Results: Monopolar RF led to neocollagenesis in the papillary dermis, and upper, mid, and deep reticular dermis, and neoelastogenesis in the papillary dermis, and upper and mid reticular dermis. HIFU led to neocollagenesis in the mid and deep reticular dermis and neoelastogenesis in the deep reticular dermis. Among these treatment methods, HIFU showed the highest level of neocollagenesis and neoelastogenesis in the deep reticular dermis. Conclusions: HIFU affects deep tissues and impacts focal regions. Monopolar RF also affects deep tissues, but impacts diffuse regions. We believe these data provide further insight into effective skin tightening.

Estrogen and progesterone receptors in congenital melanocytic nevi

Congenital melanocytic nevi (CMN), arising from the proliferation of melanocytes, manifest at birth and are colloquially termed as bathing trunk, coat-sleeve, or stocking nevi. These lesions, occurring in approximately 1 to 2% of neonates, predominantly localize over the trunk and thigh regions. Giant congenital nevi, characterized by a size exceeding 20 cm, often present with pigmentation and hairiness. Herein, we present the case of a 14-year-old patient diagnosed with a giant congenital nevus (bathing trunk nevus) accompanied by lipomatosis, while concurrently reviewing the literature to delineate this rare association. Our investigation identified a total of six cases, comprising five females and one male. Notably, half of the cases (3/6) exhibited multiple lipomatous lesions, with the back region emerging as the most prevalent site. In our presented case, progressive enlargement of a soft tissue mass in the right flank prompted excision, revealing a well-circumscribed lipomatous lesion infiltrated diffusely by benign-appearing melanocytes within fat lobules, as confirmed by immunohistochemistry. Specifically, positivity for HMB45 and S100 markers was observed. Beyond the rarity of such occurrences, our report underscores the infrequent concomitance of CMN with lipomatosis.

An Unusual Pigmented Plaque in a Newborn.

One or more large nodules may occasionally appear in a congenital nevus. As a rule, the nevus is of the “large” or “giant” type and the patient is very young. However, similar nodules can be rarely found in smaller congenital nevi and analogues can even appear in adulthood. The nodules may protrude above the surface of the congenital nevus or can be situated deeply within the lesion. The common denominator of the nevi in which proliferative nodules occur seems to be their depth rather than their diameter. In most cases, the deep reticular dermis and subcutaneous septa contain cords and strands of small, round melanocytes.KeywordsMelanocytic NevusBlue NevusCongenital Melanocytic NevusCongenital NevusCongenital Giant Melanocytic NevusThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Familial clustering of giant congenital melanocytic nevi

A 27‐year‐old woman presented with a 2‐year history of a progressively enlarging, painful ulcer on her right foot. Two years earlier, she had noticed an apparent wart on her right foot. The lesion had been treated with liquid nitrogen. An ulcer developed at the site of treatment and enlarged progressively, becoming so painful that she had difficulty walking. Extensive surgical debridement and closure were unsuccessful in healing the ulcer; the ulcer grew larger and more painful. After an amputation was recommended by her local doctors, the patient sought another opinion.At physical examination, the patient had a painful, 9.5 cm × 5 cm ulcer on the plantar aspect of the right foot (Fig. 1). Exuberant, rolled borders were present, and a yellow exudate covered the base of the lesion. The right inguinal lymph nodes were enlarged and firm. A punch biopsy specimen from the ulcer border was examined.A 27‐year‐old woman presented with a 2‐year history of a progressively enlarging, painful ulcer on the right foot. At physical examination, she had a painful, 9.5 cm × 5 cm ulcer on the plantar aspect of the right footimageMicroscopic examination of a hematoxylin and eosin preparation of the punch biopsy specimen showed a reasonably well‐demarcated neoplasm within the deep reticular dermis down to the dermal‐pannicular junction (Fig. 2). This proliferation was composed of a population of round cells and spindle cells. The round cells were arranged in nests separated by delicate, fibrous septa, and the spindle cell proliferation was intercalated between collagen bundles. The nuclei of both cell types were uniform and vesicular with prominent nucleoli. No typical or atypical mitotic figures were identified within this proliferation. Staining with S‐100 protein was strongly positive. These findings were consistent with a clear cell sarcoma.Microscopic examination of the punch biopsy specimen from the edge of the ulcer in Fig. 1 showed a neoplasm composed of round cells and spindle cells in the deep reticular dermis (hematoxylin and eosin; A, × 100; B, × 400)imageA biopsy specimen from the right inguinal lymph node was positive for metastatic clear cell sarcoma. Chest radiography and computed tomography showed multiple nodules throughout both lungs. The patient received five cycles of therapy with cisplatin, vinblastine, dacarbazine, and interferon‐α, and is alive 2 years later.

Surgical treatment of large and giant congenital melanocytic nevi (GCMN) of the upper extremity is challenging because of limited options for reconstruction. A preexpanded distant flap is considered an important option in upper extremity reconstruction, where the soft tissue available for use is limited. The authors aimed to refine the preexpanded distant flap after excision of the GCMN in the upper extremity. Large (>10 cm) and giant (>20 cm) congenital melanocytic nevi of the upper extremities treated with tissue expansion and distant flaps over 10 years were retrospectively reviewed, and the authors describe in detail the surgical strategies for reconstruction of the upper extremity with a distant flap. From March of 2010 to February of 2020, 13 patients (mean age, 2.87 years) treated with 17 preextended distant flaps were included. The mean flap dimension was 154.87 cm 2 , ranging from 15 × 5 to 26.5 × 11 cm. All procedures were successfully completed except for one, in which partial flap necrosis occurred. Preconditioning was performed before flap transfer in 5 patients with larger rotation arcs and flap dimensions. The mean duration of postoperative follow-up was 51.85 months. A new reconstructive protocol was proposed that combined the 3 elements, including a distant flap, tissue expander, and preconditioning. In the treatment of GCMN in the upper extremities, careful planning and multiple stages are required. For pediatric patients, the preextended distant flap with preconditioning is useful and effective for reconstruction. Therapeutic, IV.

Large café-au-lait spots on a 5-year-old boy

We describe a case of a melanocytic proliferation arising in a giant congenital melanocytic nevus (CMN) and outline the potential utility of an immunohistochemical study with PReferentially expressed Antigen in MElanoma (PRAME) in distinguishing benign proliferative nodules (PN) from melanoma in this context. A 15-day-old girl presented with a fibrotic nodule clinically suspicious for melanoma within a giant CMN. Histopathological examination showed a predominantly intradermal melanocytic nevus with congenital features intermixing with an ill-defined proliferation of larger melanocytes demonstrating mild-to-moderate cytologic atypia and increased mitotic activity. Anti-PRAME was diffusely positive within the congenital nevus while negative within the larger proliferating cells. Chromosomal microarray analysis revealed whole chromosomal gains and losses only, consistent with a PN arising in a giant CMN. To our knowledge, PRAME expression in giant CMN, PN, and pediatric melanomas has not been previously described. Based on our experience with this case, we propose that differential patterns of PRAME expression may be present in these three lesions, allowing PRAME immunohistochemistry to potentially serve as a helpful adjunct diagnostic tool for laboratories that do not readily have access to molecular testing in rendering a diagnosis for atypical melanocytic proliferations arising in giant CMN.

Congenital melanocytic nevi (CMN) are proliferations of cutaneous melanocytes which are present at birth or may develop during the first postnatal weeks. In 50% of the cases, hypertrichosis is also present. Lasers as CO2, normal mode ruby, Q-switched ruby, Q-switched alexandrite (755 nm) and Qswitched neodymium:yttrium-aluminium-garnet (Nd:YAG) 532 and 1064 nm can be used for the treatment of some CMN. There is a new technique of treatment for the congenital melanocytic nevi with hypertrichosis with a good improvement on reducing pigmentation and hypertrichosis. The authors describe their experience with a new laser technique for the depigmentation and the epilation of CMN with hypertrichosis: the Depilendolaser (Depigmentation Epilation, Endolaser) technique. In this procedure, CMN were treated with a subcutaneous approach by a LBO diode-pumped laser Quanta D - Quanta System S.p.A., Italy (wavelength = 532 nm) and with a cutaneous approach by Versapulse Select Lumenis® (wavelength = 532 nm). Histology was performed on CMN tissue samples. Over a 2-year period, 25 subjects were treated using Quanta D ® (wavelength = 532 nm) power 8 W, frequency 4.9 Hz and 0.48 J/60 ms pulse, through a 300-μm fibre optic for treatment from underneath the derma to the surface, and using the frequency-doubled Q-switched Nd:YAG laser (wavelength = 532 nm) Versapulse Select (Lumenis Ltd.,Yokneam, Israel) QS 532 nm, round spot size of 3 mm in diameter, fluence 2 J/cm2, energy 0.20 J/10 ms pulse and frequency 10 Hz, for the treatment from the surface to the depths. The Depilendolaser technique resulted to produce greater hair loss in the treated area with significant depigmentation and a relevant aesthetic improvement. Histopathological examination of the lesions after treatment, in comparison with non-treated areas of the same gigantic nevi, shows loss of pigmented melanocytic nests and hair follicles—often numerous and normotrophic in these congenital nevi—disappear after treatment with the new laser technique. The authors describe a new laser technique for depigmentation and epilation and their experience in the treatment of CMN with hypertrichosis. Data collected in this study showed first of all an extreme safety and tolerability of the procedure in children and young patients, with no adverse effects such as skin atrophy, pathological scarring and aesthetic improvement. Level of evidence: Level I, therapeutic; risk/prognostic study.

Serum levels of S-100 protein are directly proportional to the size, number, thickness and degree of cellularity of congenital melanocytic nevi