Partial unilateral lentiginosis with ipsilateral Lisch nodules and axillary freckling

A 9-year-old Taiwanese girl had an unusual combination of multiple lentigines clustered on her left face, 3 cafe-au-lait spots on her left arm and ipsilateral axillary freckling. Two Lisch nodules of the iris were recognized in the left eye but none in the right eye, which is why we established a diagnosis of segmental neurofibromatosis 1. No family member had any sign of neurofibromatosis 1. Moreover, the patient had a large speckled lentiginous nevus involving the left side of her trunk, and her father showed a similar skin disorder on his left buttock. These lesions were taken to be unrelated to the patient's segmental neurofibromatosis 1. This case provides further evidence in favor of the concept that partial unilateral lentiginosis represents a mosaic manifestation of type 1 neurofibromatosis.     

Round excision of small, benign, papular and dome-shaped melanocytic nevi on the face

BACKGROUND: Patients frequently request the removal of benign, papular and dome-shaped nevi for cosmetic or functional reasons. Total excision is probably the most widely used method of removal. AIM: To introduce the round excision technique for the treatment of benign, papular and dome-shaped nevi on the face. METHODS: In a prospective study, 36 benign, papular or dome-shaped nevi of all types were removed by the round excision technique. The lesions were circumscribed with a number 15 scalpel blade, 2 mm beyond the limits, with incision to the full depth of the dermis, and removed by cutting horizontally at the maximum depth of the circular incision. Histologic examinations were performed for all specimens. RESULTS: Complete removal of nevi was achieved in all patients with excellent or good cosmetic results. Of the 36 nevi, 24 were intradermal and 12 were compound nevi. Dog-ear formation was observed in only one patient. CONCLUSION: Round excision may be a better alternative to conventional fusiform or shave excision of benign, dome-shaped or papular nevi of the face.     

Estrogen and progesterone receptors in melanocytic lesions. Occurrence in patients with dysplastic nevus syndrome

Estrogen and progesterone binding studies in a series of 22 melanocytic lesions from 14 patients with the dysplastic nevus syndrome were done using a fluorescent estrogen and progesterone binding technique. Melanocytic lesions from these patients, including primary cutaneous melanomas, dysplastic nevi, and benign nevi, contained large numbers of estrogen and progesterone binding cells. Comparison is made to a series of control intradermal nevi that had little or no detectable estrogen or progesterone binding. Increased hormonal binding, and possibly responsiveness, is seen in melanomas, melanoma precursor lesions such as dysplastic nevi and congenital nevi, as well as benign nevi from patients with the dysplastic nevus syndrome.     

Expression of activated Akt in benign nevi, Spitz nevi and melanomas

BACKGROUND: Activated Akt expression (p-Akt) is reportedly increased in many melanomas as compared with benign nevi. The purpose of this study was to evaluate and compare p-Akt immunohistological staining in benign nevi, Spitz nevi and primary melanomas. METHODS: Immunostaining for phosphorylated Akt was performed in 41 melanocytic lesions previously classified as benign intradermal nevus (14 lesions), Spitz nevus (9 lesions) or melanoma (18 lesions). Lesions were graded for intensity of p-Akt staining by two independent observers (0, no staining; 1, slightly positive; 2, moderately positive; 3, highly positive). Scores were averaged, and statistical analyses were performed. RESULTS: Benign nevi showed less staining (mean score 1.18) compared with Spitz nevi (mean score 2.11) and melanomas (mean score 2.19). This difference was statistically significant between benign nevi and melanomas (p = 0.0047) and benign nevi and Spitz nevi (p = 0.0271). No statistical difference was detected in staining between Spitz nevi and melanomas (p = 0.8309). CONCLUSIONS: Activated Akt expression is increased in Spitz nevi and melanomas as compared with benign intradermal nevi, but is unlikely to prove useful in differentiating between the former.     

Linear cutaneous neurilemmomas on the forehead

A 35-year-old woman had had pruritic linearly arranged papules on the right side of her forehead for 17 years. A biopsy specimen from one of the papules showed the histopathological appearance of an intradermal plexiform neurilemmoma. No other features of systemic neurofibromatosis or neurilemmomatosis were detected. Neurilemmoma usually occurs as a solitary lesion in the subcutis and there are only few reports of such localized multiple intradermal neurilemmomas associated with neither neurofibromatosis nor neurilemmomatosis.     

Mycobacterium gordonae infection of the hand

A 70-year-old woman was seen for two chronic nodules on the dorsum of her left hand. They had a uniquely mamillated surface, but histopathologically showed nonspecific granulomatous changes with no organisms seen. Laboratory studies disclosed the lesions were due to Mycobacterium gordonae, an organism commonly ignored as a pathogen. The histopathologic changes were reproduced by intradermal testing with tuberculin. The lesions, unaffected by ketoconazole, as well as by a variety of antibiotics, including minocycline hydrochloride, slowly involuted during a one-year period. To our knowledge, this patient is the first documented case of cutaneous infection from this organism. Mycobacterium gordonae must be added to the list of true mycobacterial pathogens.     

Sclerosing segmental neurofibromatosis

Segmental neurofibromatosis is a rare disorder characterized by cafe-au-lait macules and/or neurofibromas limited to a single body segment. The neurofibromas in segmental neurofibromatosis are usually soft, non-tender nodules as in other types of neurofibromatosis. Histopathologically, they are usually non-encapsulated, loosely textured dermal tumors. We report a case of sclerosing segmental neurofibromatosis, in which the patient presented with several grouped, erythematous to brownish, firm tender nodules on the left side of the posterior neck. Histopathologically, the stroma was mostly very fibrotic, especially around hair follicles, in addition to the usual features of neurofibroma. The atypical clinical feature, hardness, and tenderness of the lesions may be associated with the fibrosis.     

Segmental neurofibromatosis in association with a large congenital nevus and malignant melanoma

We describe a patient with segmental neurofibromatosis and a large congenital nevus who developed malignant melanoma in the same anatomic distribution. The overlapping presentation suggests a common etiologic link between neurofibromatosis and large congenital nevi and the possibility that neurofibromatosis increases the risk of melanoma with large congenital nevi.     

Proliferation, apoptosis, and survivin expression in a spectrum of melanocytic nevi

BACKGROUND: Apoptosis is important for maintenance of tissue homeostasis and often dysregulated in cutaneous neoplasms. The apoptosis inhibitor survivin is expressed in melanoma and non-melanoma skin cancers and benign keratinocytic lesions. Its expression has not been studied in melanocytic nevi. OBJECTIVE: We determined the expression pattern of survivin in benign melanocytic nevi in comparison to markers of proliferation and apoptosis. METHODS: Six cases of each of the following melanocytic nevi were retrieved from a dermatopathology archive: compound dysplastic nevus, intradermal nevus, compound nevus, neurotized intradermal nevus, and Spitz nevus. Survivin expression was evaluated by in situ hybridization. Apoptotic and proliferation indices were calculated by counting immunoreactive cells in terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling and proliferating cell nuclear antigen immunostained sections, respectively. RESULTS: All nevi, regardless of histologic type, expressed survivin. Compound melanocytic lesions expressed survivin in both epidermal and dermal compartments. The apoptotic rate was low for dysplastic, compound, and Spitz nevi, and apoptotic cells were not identified in any neurotized nevus. The proliferative index was highest for Spitz nevi, while all other nevi demonstrated rare positive cells. CONCLUSIONS: Survivin is consistently expressed in benign melanocytic lesions, while apoptotic cells are rarely identified, suggesting the dysregulation of apoptotic pathways with the accumulation of cells in these neoplasms.     

婴幼儿先天性色素痣126例临床及病理特征分析

【摘要】 目的 总结婴幼儿先天性色素痣的临床及病理特征。方法 回顾性分析2015年1月至2020年1月在西京皮肤医院确诊的126例婴幼儿先天性色素痣患儿的临床及病理资料。计数资料比较采用χ2检验。结果 126例婴幼儿先天性色素痣患儿中,男68例,女58例;86.5%的患儿出生即有皮损;57.9%就诊年龄2 ~ 3岁。皮损发生部位包括头面部（76例,60.3%）、躯干（24例,19.1%）、四肢 （26例,20.6%）。36例（28.6%）为先天性小痣,68例（54.0%）为M1型中型痣,13例（10.3%）为M2型,9例（7.1%）为巨痣。121例（96.0%）皮损单发,5例（4.0%）多发,44例（34.9%）痣伴粗毛,15例（11.9%）伴丘疹/增生性结节,6例（4.8%）有卫星灶。病理亚型包括混合痣120例（95.2%）、皮内痣4例（3.2%）和交界痣2例（1.6%）。38例（30.1%）镜下皮损深度< 1 mm,61例（48.4%）1 ~ 2 mm,25例（19.8%） > 2 mm,45例（35.7%）浸润至皮下脂肪层或更深。126例色素痣皮损中,常见病理特征包括痣组织成熟现象（100%,不包括2例交界痣）,角质层色素颗粒（42.1%）,分布紊乱/不对称（63.5%）,表皮痣细胞散在分布（72.2%）和呈Paget样扩散（53.2%）,真皮可见噬黑素细胞（56.4%）,痣细胞沿毛囊皮脂腺分布（65.1%）等。特殊病理特征包括痣细胞嵌入血管/淋巴管腔内（33.3%）、痣细胞松解（35.7%）、纤维瘤样改变（19.8%）、累及立毛肌（24.6%）、肥大细胞浸润（23.8%）等。不同临床表现的婴幼儿先天性色素痣病理模式：浸润深度 > 2 mm、角质层色素颗粒和角质层柱状色素颗粒在巨痣中的发生率明显高于其他大小皮损（χ2 = 7.93、10.76、5.89,均P < 0.05）;浸润深度 > 2 mm、表皮海绵水肿伴痣细胞散在分布、痣细胞巢沿毛囊皮脂腺分布、纤维瘤样改变、肥大细胞浸润在伴有粗毛皮损中的发生率明显高于不伴粗毛者（χ2 = 28.29、8.11、6.22、7.92、8.19,均P < 0.01）;表皮痣细胞呈Paget样扩散、痣细胞有异型性在伴丘疹/增生性结节的皮损中的发生率高于不伴丘疹增生性结节的皮损（χ2 = 4.92、6.30,均P < 0.05）。结论 婴幼儿先天性色素痣的临床及组织病理具有独特性,细胞常见不典型性,确诊及治疗选择需要密切结合临床与病理特征。     

Segmental neurofibromatosis

A 74-year-old man presented with skin-colored nodules in his left antecubital fossa. The lesions had been present for 35 years and were asymptomatic. Nodules elsewhere on the body, cafe-au-lait spots, axillary freckling, and Lisch nodules were absent. No family members had similar nodules. A diagnosis of segmental neurofibromatosis was made, and a biopsy specimen of a nodule showed a neurofibroma. As the patient had no complications of neurofibromatosis 1, no treatment was needed.     

Desmoplastic melanocytic nevi with lymphocytic aggregates

Desmoplastic melanocytic nevi can be difficult to distinguish from desmoplastic melanoma. The presence of lymphocytic aggregates in association with a sclerosing melanocytic proliferation is commonly regarded as a feature in support of a diagnosis of desmoplastic melanoma. However, the finding is not specific for melanoma. Herein we report six cases of sclerosing melanocytic nevi with associated lymphocytic aggregates. They occurred in five women and one man, ranging in age from 11 to 61 years. Three lesions were sclerosing Spitz nevi; one was an amelanotic sclerosing blue nevus, one an acquired intradermal sclerosing nevus, and one was a congenital compound melanocytic nevus with sclerosis of its dermal component. The lesions were interpreted as benign, i.e. melanocytic nevi, because of their histopathologic attributes (symmetric silhouette, benign cytologic features) and results from immunohistochemical studies (all lesions strongly expressed Melan-A and p16) and fluorescence in situ hybridization (FISH). Three lesions tested by FISH lacked copy number changes of 11p, 6q or 6p. None of the lesions recurred. The cases highlight that contextual information is essential for the diagnosis of desmoplastic melanoma and sclerosing nevus. The presence of lymphocytic aggregates per se does not prove that a sclerosing melanocytic proliferation is malignant.     

Multiple cutaneous melanoma metastases

An 84-year-old white woman presented with diagnosed vascular failure in the left leg. The patient had had diabetes mellitus for over 50 years. Five years earlier, her right leg was amputated because of an obliterating arteriopathy. At the time of hospitalization, she showed dry gangrene in all the toes on her left foot. A laser Doppler test performed on the left leg showed severe peripheral arteriopathy affecting the anterior and posterior tibial arteries, with a Windsor index of 20% in her ankle. On physical examination, the patient showed several nodular lesions on the anterior and anterior-medial surface of her left leg. These lesions were infiltrated, of a hard elastic consistency, and occasionally confluent, with a diameter ranging from 0.5 to 4 cm (Fig. 1) and the color varying from ochre-yellow to brownish-red to slate-brown. The patient reported that these lesions had erupted approximately 2 years earlier and had been accompanied by itching and mild burning. She had shown them to her family doctor who had diagnosed seborrhoeic keratosis. A series of biopsies performed on the nodules revealed the presence of atypical melanocytes arranged in alveolar formations that reached the epidermis. The epidermis appeared thin, compressed, and atrophic; no signs of junctional activity could be seen (Fig. 2). The tumor cells were round, with a clear cytoplasm and atypical, hyperchromatic, oval nuclei containing nucleoli (Fig. 3). Some atypical melanocytes contained small amounts of melanic pigment that was concentrated in the cytoplasm of macrophages which were mixed with the elements of the tumor. There had been no melanoma in the clinical history of the patient. The patient had a chest roentgenogram with tomography and a computer tomography (CT) scan of the liver, spleen, mediastinum, and brain, all with negative results. The case is worth reporting because of the peculiar cutaneous lesions that could suggest several diagnostic hypotheses. The clinical picture could have been interpreted as being Kaposi's sarcoma, seborrhoeic keratosis, angiosarcoma, or multiple Spitz nevi. A Spitz nevus is a benign variant of a compound nevus that is characterized histopathologically by atypical, large melanocytes with abundant eosinophilic cytoplasm and large vesicular nuclei with prominent nucleoli. Histologic examination removed any doubt, suggesting a metastatic origin for the proliferating nodules. Marked expression of S-100 protein and of HMP45 was found by immunohistochemistry; HMP45 was also intensely positive in the deep layers of the dermis. It was not possible to define the site of the primary lesion from the patient's history or from physical examination;^1,2 however, one cannot exclude that the primary lesion was at the same site as where the metastases had diffused, either by growing spontaneously from healthy tissue or through a transformation of anevus.^3,4     

Eccrine angiomatous hamartoma

A 7-year-old girl presented with asymptomatic bruise-like hairy nodules on her right lower leg since 8 months of age. Histopathology demonstrated an increased number of blood vessels and eccrine glands, thicker collagen bundles, and a terminal hair follicle in catagen phase. The patient was diagnosed with multiple eccrine pilar angiomatous nevi, an unusual variant of eccrine angiomatous hamartomas. The natural course of eccrine angiomatous hamartomas is typically slow growth and benign behavior. Simple excision is usually curative and is reserved for painful or cosmetically disfiguring lesions. Our patient's nevus is large and multifocal, making excision more challenging.     

Unna's and Miescher's nevi: two different types of intradermal nevus: hypothesis concerning their histogenesis

In 1991, we tentatively introduced the classification of Ackerman and Magana-García for acquired melanocytic nevi in our laboratory. We soon realized that every acquired intradermal melanocytic nevus might be easily classified into either Unna's or Miescher's patterns and that this classification had both clinical implications and significant histological differences. The decisive discriminative feature between Unna's and Miescher's nevi is that Unna's nevus is an almost purely adventitial lesion confined to expanded papillary dermis and, many times, to the perifollicular dermis too. In Miescher's nevus melanocytes diffusely infiltrate both adventitial and reticular dermis in a wedge-shaped pattern. With these concepts in mind, every acquired intradermal melanocytic nevus can be easily classified as either Unna's or Miescher's. We studied 751 acquired melanocytic nevi; 458 (61%) of them were intradermal; of these, 234 were Unna's nevi and 224 were Miescher's nevi. Eighty- three per cent of the nevi from the head and neck were intradermal nevi, whereas on the trunk and limbs junction and compound nevi were the most frequent (56%). When intradermal nevi were divided into Unna's and Miescher's patterns, it resulted that 91% of Miescher's nevi located on the face and 94% of intradermal nevi on the face were Miescher's nevi. In contradistinction, 87% of the Unna's nevi located on the neck, trunk, and limbs, and 96% of intradermal nevi from these locations were Unna's nevi. Only on the scalp was there no clear predominance of one type of intradermal nevus. A series of other histological characteristics were significantly predominant (P = 0.000) in either Unna's or Miescher's nevi. Unna's nevi had more: junctional nests above the intradermal component (40% versus 20%), a radial pattern of intradermal nests (38% versus 0%), vascular-like clefts lined by nevus cells (48% versus 4%), and in depth maturation (94% versus 0%). Miescher's nevi had more: pilosebaceous follicles within the nevus (100% versus 51%), subnevis folliculitis (12% versus 1%), large isolated melanocytes along the basal epidermal layer (47% versus 11%), multinucleated nevocytes (89% versus 44%), and adipocytes within the nevus (53% versus 11%). In conclusion, Unna's and Miescher's nevi are 2 subsets of acquired melanocytic nevus with clinical implications and significant histological differences. A histogenetic hypothesis is proposed on the basis of their histological structure.     

S100A6 preferentially labels type C nevus cells and nevic corpuscles: additional support for Schwannian differentiation of intradermal nevi

BACKGROUND: Melanocytic nevi typically show a morphologic sequence of maturation from epithelioid "type A" cells to fusiform, Schwann cell-like "type C" cells with dermal descent. Nevi may also produce Wagner-Meissner-like structures (nevic corpuscles). Previous studies have shown that this maturation of intradermal nevi recapitulates intermediate stages in Schwann cell development. In intradermal nevi, we have evaluated the pattern of S100A6 protein, a form of S100 found in Schwann cells. METHODS: Formalin-fixed, paraffin-embedded archival tissues were evaluated by immunohistochemistry using antibodies specific for S100A6 and S100B in 38 intradermal nevi (IDN). Ten neurofibromas (NF), 3 Schwannomas (SCH), 2 palisaded and encapsulated neuromas (PEN), and 2 granular cell tumors (GCT) were included as positive controls since these lesions have large numbers of Schwann cells. RESULTS: Melanocytic nevi demonstrated preferential anti-S100A6 staining of "type C" cells (36/38; 28 strong, 8 weak) and nevic corpuscles (25/38; 19 strong, 6 weak) compared to "type A" cells (17/38; 17 weak) and "type B" cells (17/38; 4 strong, 13 weak). All NF, SCH, and PEN stained strongly with anti-S100A6. Both GCT were negative with anti-S100A6 but positive with anti-S100B. CONCLUSIONS: The pattern of S100A6 expression in intradermal nevi further supports the hypothesis that maturation in these lesions recapitulates features of Schwann cell differentiation. The lack of S100A6 expression by both GCT suggests that these lesions have lost this feature of Schwann cells, which may play a role in their peculiar phenotypic appearance.     

Increased nevus estrogen and progesterone ligand binding related to oral contraceptives or pregnancy

Melanocytic nevi excised from women who were pregnant or had given birth less than 1 month previously or from women who were taking oral contraceptives were studied with the use of a fluorescent estrogen and progesterone ligand binding assay. All nevi from these patients had markedly increased numbers of estrogen- and progesterone-binding cells, similar to those observed in melanoma and melanoma precursor lesions. In contrast, nevus cells in acquired intradermal nevi from women who were not pregnant nor taking oral contraceptives had few or no detectable estrogen- or progesterone-binding cells. The induction of increased hormonal receptors by pregnancy or oral contraceptives may be related to an increased risk of melanoma and melanoma precursor lesions in specific subsets of patients, as well as to the pigmentary changes observed in female patients in general.     

Melanocytic nevi are associated with neurofibromas in neurofibromatosis, type I, but not sporadic neurofibromas: a study of 226 cases

BACKGROUND: Neurofibromatosis, type 1, is associated with cutaneous melanin pigmentation, but an association with ordinary melanocytic nevi has not been described. METHODs: This retrospective case-control study was designed to see if neurofibromas in patients with neurofibromatosis, type 1 (NF-1) differ from sporadic neurofibromas (SN) in their incidence of associated melanocytic nevi and other histologic features. Slides from 114 NF-1 were compared with 112 SN and 300 intradermal melanocytic nevi (IDN). RESULTS: Small lentiginous melanocytic nevi were identified over 13 NF-1 (11%) but no SN (P=0.0002). Compared with other NF-1, NF-1 with nevi were more frequently associated with melanocytic hyperplasia, giant melanosomes and diffuse neurofibroma (P<0.03). Compared with SN, NF-1 were also more frequently associated with melanocytic hyperplasia, lentigo simplex-like changes, diffuse neurofibroma and plexiform neurofibroma (P<0.001). Sebaceous hyperplasia (14%), dermal elastosis (9%), lipomatous change (8%), epithelial cysts (4%) and keratin granulomas or folliculitis (3%) were not significantly different in prevalence between NF-1, SN and the control group of IDN. CONCLUSIONS: This study suggests that there is a difference in the potential for melanocytic proliferation in NF-1 compared with SN. NF-1, SN and IDN are associated with a similar range of incidental histologic changes. Ball NJ, Kho GT. Melanocytic nevi are associated with neurofibromas in neurofibromatosis, type 1, but not sporadic neurofibromas. A study of 226 cases.     

多发性先天性色素痣1例

报告先天性多发性色素痣1例,患者男,19岁,全身散在黑痔19年,皮肤科检查见头面部,躯干部,四肢密集黑色结节,大片状黑斑,皮肤增厚,质软,上有黑色毳毛生长,前后共3次手术,术后效果满意,皮损组织病理学检查显示为皮内痣。     

Giant congenital neuroid melanocytic nevus

A patient with a variety of nevus cell nevi, a congenital giant melanocytic nevus, abnormal facies, vascular anomaly of the leg, and mental retardation was examined. The patient also had neuroid elements within the giant nevus that led to the consideration of neurofibromatosis. Because neurofibromatosis is a genetically determined condition with tissue different from the neuroid elements seen in giant nevi, the two conditions are considered to be different entities. Malignant transformation of congenital giant pigmented nevi occurs, although the incidence of such transformation remains a subject of controversy.