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PubMed1989

[Primary tissue culture of nevus cell nevus--in comparison with the findings from neurofibroma culture].

Forty-two nevus cell nevi excised surgically from 40 patients were processed for primary culture. The characteristic features of cultured nevi were compared with those of neurofibroma reported previously. 1) Based on phase-microscopic findings, S-100 protein staining, and slow motion picture, most of the cultured macrophage-like cells or cells with dendrites were considered to be nevocytes. 2) The emigration of nevocytes was observed in 31 of the 42 nevus cultures (73%). Nevocytes classified histologically as the intradermal type with fatty degeneration and nevi obtained from the face and aged patients exhibited higher tendencies to ward emigration when they were cultured. 3) The cultured Schwann cells in neurofibroma and the nevus cell nevus, mainly c-type nevocytes, are both of neural crest origin. They were observed to have closely similar morphological and S-100 protein staining features.

Adolescent↗
PubMed1978

Nevus of large spindle and/or epithelioid cells (Spitz's nevus).

By now it is well recognized that there is a benign melanocytic nevus, common in the young and common enough in adults, that has histological features that are confusable with those of malignant melanoma. The anomaly is usually referred to as benign juvenile melanoma, sometimes as Spitz's nevus, and, by some histopathologists, as spindle and epithelioid cell nevus. All the histological subtleties and variations of the condition are still not fully appreciated and some of them are still being misinterpreted as those of malignant melanoma. We herewith present a study designed to clarify the issue and offer firm criteria for histological differentiation of the nevus in point from malignant melanoma. We also suggest a new name for it and supporting arguments therefor.

Adolescent↗
PubMed1981

[The significance of adrenergic receptors for the development of nevus flammeus and nevus anemicus (author's transl)].

Examination of patients with nevus flammeus or nevus anemicus showed disturbed sensibility in the area of the nevus in the majority of cases. Histologically and with special technique of histochemistry and fluorescencemicroscopy there was no evidence for neurogenic lesions. However, signs of vegetative dysfunction were present: hyperhidrosis and absent reactivity of vasculature in the nevus area to vasoconstrictive and vasodilatatory stimuli. Based on these findings a disturbed regulation of vascular intramural adrenergic receptors seemed possible and really could be demonstrated by means of autoradiography. In both types of nevi only one of the adrenergic receptors could be marked with specific antagonists. Therefore the persistent vascular dilatation and constriction can be accounted for by the absence of one of these receptors. This abnormal distribution of receptors could be due to a developmental defect influenced by the "nerve growth factor".

Adolescent↗
PubMed1994

Solomon's epidermal nevus syndrome (type: linear nevus sebaceus) and hypophosphatemic vitamin D-resistant rickets.

BACKGROUND: Epidermal nevus syndrome is very variable in symptoms and associated abnormalities. Synonyms of this syndrome are linear nevus sebaceus syndrome or Schimmelpenning-Feuerstein-Mims syndrome or Solomon syndrome. The combination with vitamin D-resistant rickets is rare and only sporadically described. Less than 10 cases with this combination of symptoms have been described in the literature. OBSERVATIONS: We describe a boy suffering from epidermal nevus syndrome (type: nevus sebaceus). This child also presented with severe rickets with hyperphosphaturia, resistant to vitamin D. Our patient was seen in consultation at birth, but after a delay of 4 years we were consulted again for a second opinion and treatment; the vitamin D-resistant rickets was recognized. Treatment with 1,25-dihydroxy vitamin D3 and phosphorus resulted in healing of rickets. Removal of parts of the tumors did not influence the rickets. This is in contrast with a formerly described case. Removal of fibroangiomas led in that case to normalization of the alkaline phosphatase, calcium, and phosphate serum levels. CONCLUSIONS: The rickets results from massive phosphate excretion by defective renal tubular reabsorption of phosphate. In all patients described, rickets developed at an early age. Clinical symptoms were marked bone abnormalities, muscle weakness, and bone pain.

Child↗
PubMed1995

The eastern Australian childhood nevus study: prevalence of atypical nevi, congenital nevus-like nevi, and other pigmented lesions.

BACKGROUND: Various melanocytic lesions are frequently observed. An understanding of phenotypic factors and environmental stimuli that are associated with these lesions may help explain their pathogenesis. OBJECTIVE: This study was undertaken to determine the prevalence of atypical nevi, blue nevi, cafe-au-lait macules, congenital nevus-like nevi, halo nevi, nevi spili, nevi 5 mm or more in diameter, and skin-colored melanocytic nevi in a population of schoolchildren and to explore risk factors including solar radiation in the development of these melanocytic lesions. METHODS: A cross-sectional study was performed by the same medical investigators to examine schoolchildren in three Australian cities that span a wide range of latitudes. RESULTS: Data from 1123 white Australian schoolchildren, 6 to 15 years of age, were analyzed. Acquired melanocytic nevi (atypical nevi, nevi > or = 5 mm in diameter, and skin-colored nevi) were more likely to develop in older fair-skinned subjects who had freckles and lived closest to the equator. Café-au-lait macules and congenital nevus-like nevi were observed in 36.3% and 4.4% of the total population, respectively. Prevalence for both these types of melanocytic lesions increased significantly with decreasing latitude. Halo nevi were present in 5.3% of the subjects and were usually solitary. These lesions were related to the presence of atypical nevi primarily by virtue of their size rather than of other features of clinical atypia. CONCLUSION: Like melanocytic nevi in general, large and atypical nevi are strongly influenced by geographic location and, by implication, degree of solar radiation. The same can be said for congenital nevus-like nevi, which suggests that many so-called congenital nevi are in fact acquired early in life.

Adolescent↗
PubMed1998

Cellular blue nevus with atypia (atypical cellular blue nevus): a clinicopathologic study of nine cases.

Atypical cellular blue nevus (ACBN) has clinicopathologic features intermediate between typical cellular blue nevus (CBN) and the rare malignant blue nevus (MBN)/malignant melanoma (MM) arising in a CBN. Herein we report 9 cases of ACBN. The patients were caucasian (6 females and 3 males) with a mean and median age of 47/51 years. Two patients complained of recent changes and about half of these tumors were located on the buttocks or scalp, averaging 1.5 cm in diameter. Histologically, they were characterized by architectural atypia (infiltrative margin and/or asymmetry) and/or cytologic atypia (hypercellularity, nuclear pleomorphism, hyperchromasia, mitotic figures, and/or necrosis). Assessment of the expression of 3 tissue markers demonstrated rare solitary cell staining with oncogene product bcl-2, and a proliferative index of 23+/-19 and 39+/-30 cells/10 high power field with antibodies to PCNA and Mib-1, respectively. No significant differences were detected comparing the above levels of expression to a control group of 15 CBN; however, ACBNs tended to show a higher proliferative index by PCNA and Mib-1 as well as a significantly higher mitotic rate (1/10 HPF vs. 0; p=0.001). Analysis of DNA content showed DNA aneuploidy in both groups. Follow-up data on 9 of 9 patients showed 1 patient dead without disease and 8 alive without disease (mean/median follow-up 42/32 months, range 15-96 months). No patient during this follow-up time has experienced either a local recurrence or lymph node or visceral metastasis. These findings highlight the close resemblance of ACBN to the natural history of CBN. Nevertheless, many of the distinguishing histologic features of ACBN are also those of MBN. Because of these intermediate clinicopathologic features, ACBN warrant close scrutiny and long-term follow-up.

Adolescent↗
PubMed2001

[Occult dermal primary melanoma in congenital nevus-cell nevus].

Malignant melanomas normally arise at the dermoepidermal junction. Development of these tumours in deeper layers of the dermis without having contact with the junction is rare. A small congenital melanocytic nevus localized in the region of the waist band was excised because of mechanical irritation; it had not shown any changes over years. A thorough examination of the whole body did not give any clue to a malignant melanoma. Histologically a compound nevus with the typical architecture of a congenital melanocytic nevus was found. In the deeper dermis there was an isolated nodule of extremely atypical melanocytes with minimal pigmentation of melanin. S100 antigen could be demonstrated throughout the whole tumour whereas HMB45 was only found at the dermoepidermal junction. There was no marking of the tumour cells with a pancytokeratin antibody. A histological relationship between the new tumour and a mixed tumour of the left testicle, which had been excised 3 years ago, could be excluded. We did not find any metastases neither by image-aided methods nor by sentinel lymph node biopsy.

Adult↗
PubMed2006

[Becker's nevus associated with epidermal nevus: another example of twin spotting?].

Linear epidermal nevi are believed to be caused by an autosomal dominant lethal mutation that can only be expressed by mosaicism. Becker's nevus can be explained by paradominant inheritance which is only manifested clinically by an acquired loss of heterozygosity. We present the case of a 16-year-old female with an epidermal nevus located on the left side of the neck, and also a Becker's nevus located on the ipsilateral shoulder. It is interesting to speculate that this supposed double mosaicism could be another example of "twin spotting" or non-allelic didymosis, although the possibility that this is a chance association cannot be ruled out, as the lesions are not closely associated.

Adolescent↗
PubMedDate not supplied

The spectrum of epidermal nevi: a case of verrucous epidermal nevus contiguous with nevus sebaceus.

During the normal development of skin, pluripotential cells give rise to keratinocytes, sebaceous glands, hair follicles, apocrine glands, and eccrine glands. In epidermal nevi, these components emerge in an abnormal mixture within a circumscribed site. Many authors have categorized epidermal nevi based on their predominant component; however, there is often notable overlap that occurs within a single area or within contiguous areas. We report a verrucous epidermal nevus contiguous to a nevus sebaceus of Jadassohn. The categories of epidermal nevi are somewhat artificial. Our case supports the view that epidermal nevi have a spectrum of manifestations, including verrucous epidermal nevi and nevus sebaceus of Jadassohn.

Diagnosis, Differential↗
PubMed1990

Melanocytes of a melanocytic nevus in a lymph node from a patient with a primary cutaneous melanoma associated with a small congenital nevus.

Aggregates of melanocytes within the parenchyma of a supraomohyoid lymph node were found in a lymph node dissection from a 52-year-old woman who had a primary cutaneous melanoma that had arisen in association with a small congenital nevus. The melanocytes in the lymph node were interpreted to be those of a benign melanocytic nevus, and not those of malignant melanoma, based on similarities in morphologic features and immunohistochemical staining between the melanocytes in the node and those in the cutaneous congenital nevus.

Female↗
PubMed2000

The relationship between melanocytes and peripheral nerve sheath cells (Part I): melanocytic nevus (excluding so-called "blue nevus") with peripheral nerve sheath differentiation.

Among thousands of specimens of melanocytic nevi, not including giant congenital melanocytic nevus or blue nevus, 42 melanocytic nevi that showed peripheral nerve sheath differentiation were collected. The patterns of melanocytic nevi with peripheral nerve sheath differentiation may be classified into three groups: 1) "neurotized and neural nevi" with nests of "neuroid cords" and "nevic corpuscles" (the most common pattern); 2) nerve fascicle-like structures with no relation to neurotized and neural nevi; and 3) palisading melanocytes of a nevus in nests of conventional melanocytic nevi (a rare pattern). Each pattern may represent a different expression of nerve sheath differentiation in melanocytic nevi. Some melanocytic nevi with nerve fascicle-like structures show discrete structures closely resembling authentic nerve fascicles, confirming a close relationship between melanocytes and peripheral nerve sheath cells (Schwann cells and probably perineurial cells in part) and suggesting derivation of the two types of cells from common precursor cells of the neural crest and their de novo development in the dermis rather than by Abtropfung of melanocytes from the epidermis. In addition, the high prevalence of Unna, Miescher, and superficial congenital nevi in melanocytic nevi with peripheral nerve sheath differentiation suggests a different character or process for these congenital melanocytic nevi than for Clark and Spitz nevi (junctional and compound types).

Cell Differentiation↗
PubMed1989

Proliferating giant pigmented nevus: a report of an unusual tumor occurring in association with a congenital giant pigmented nevus.

A 32-year-old Japanese woman with a giant pigmented congenital nevus of the torso presented with a massive pigmented tumor mass of the vulva which grew over an 8-year period. Histologically, the tumor was composed of benign appearing nevus-like cells with focal areas of extensive fibrous response. The tumor cells were positive for S-100 protein and with an antihuman melanoma antibody (MoAb 225, 28S) stain. Electron microscopy confirmed the nevomelanocytic nature of the tumor cells and demonstrated peculiar cytoplasmic crystalline tubular structures similar to those seen in cells infected with herpes virus type II. We propose the term "proliferating giant pigmented nevus" for this previous undescribed tumor.

Adult↗
PubMed1992

Deep penetrating (plexiform spindle cell) nevus. A frequent participant in combined nevus.

This report describes 41 patients with lesions similar to those previously termed "deep penetrating" or "plexiform spindle cell" nevus (DPN). DPN occurs primarily during the first four decades, is somewhat more common in females, and has a predilection for the face, trunk, and proximal extremities. It is usually less than 1 cm in diameter and often shows variegation in color, including shades of brown, blue, and black, that create clinical concern regarding malignant melanoma. None of the present tumors nor those from the literature recurred following excision. Microscopically, DPN usually has a wedge shape, invariably involves reticular dermis, and may penetrate subcutis. Involvement of neurovascular structures and adnexae and spread between fibers of the reticular dermis create a fascicular-plexiform architecture. The melanocytes are fusiform or epithelioid, lightly to moderately pigmented, and exhibit mild to focally prominent nuclear atypia. Sparse to abundant melanophages are characteristic. Mitotic figures are few and present in only a small minority of lesions. The present study of a consecutive series also indicates that DPN is a frequent participant in combined nevus, as it was associated with ordinary nevus in two-thirds of the lesions.

Adolescent↗
PubMed1998

Phacomatosis pigmentokeratotica: speckled-lentiginous nevus in association with nevus sebaceus.

We report a case of a congenital nevus sebaceus with numerous brown macules and papules in the left auricular region. In the same lesion, pigmented basal cell carcinomas developed later in life. Additionally, on the left side of the neck, both shoulders and the left arm, features of nevus spilus with melanocytic and blue nevi were present. Such a combination of nevus sebaceus with melanocytic lesions may be explained by the concept of twin spotting and represent another case of phacomatosis pigmentokeratotica.

Basal Cell Carcinoma↗
PubMedDate not supplied

Extensive speckled lentiginous nevus associated with giant congenital melanocytic nevus: an unusual example of twin spotting?

A 15-year-old boy had an unusual combination of giant congenital melanocytic nevus on his back and a large speckled lentiginous nevus arranged in a checkerboard pattern on the dorsal and lateral aspects of his trunk. The two pigmentary nevi showed distinguishing features both clinically and histopathologically. The speckled lentiginous nevus was not noted at birth but became visible during childhood. We hypothesize that this uncommon co-occurrence may represent a further example of twin spotting and may be categorized as a new, distinct type of phacomatosis.

Adolescent↗