Adnexal-centered giant congenital melanocyte nevus with extensive ganglioneuromatous component and trisomy 7

Ganglioneuroma Arising in Congenital Melanocytic Nevus in a Patient with Cardiac Anomalies: A Case Report

A congenital melanocytic nevus is a benign melanocyte proliferation, that may be complicated by malignant transformation. We are reporting a three-year-old girl, who had a giant congenital melanocytic nevus on her back, that was treated by serial surgical excisions with tissue expander insertion. Histopathological examination confirmed the diagnosis of congenital melanocytic nevus with ganglioneuroma. Out of approximately 250 case reports on congenital melanocytic nevus, we identified only two reports of medium/large congenital melanocytic nevus with cutaneous ganglioneuroma. Due to the potential malignant transformation of congenital melanocytic nevus, reporting the features and characteristics of such rare findings may help in further understanding congenital melanocytic nevus, its associations, and prognosis.

Polypoid Dermal Dendrocytic Hamartoma in a Giant Congenital Melanocytic Nevus

Giant congenital melanocytic nevus (CMN) might be complicated by the development of several tumor types, mainly melanoma and rhabdomyosarcoma, but also poorly differentiated neoplasms. Striking polypoid exophytic masses occasionally result from neuroectodermal and neuromesenchymal hamartomatous overgrowths, which lends support to the concept of pluripotential melanoblastomatous and neurocristic origin of these lesions. The present report describes what appears to be a unique example of dermal hamartomatous polypoid CD34+ fibrogenic proliferation devoid of melanin, namely a dendrocytoma, surrounded by the melanocytes from the nevus, located in the skin of the scrotum against a background of giant CMN. The differential diagnosis included dermatofibrosarcoma protuberans, giant-cell fibroblastoma, angiofibroma, Bednar tumor, other types of dermal dendrocytic hamartoma, and neurocristic cutaneous hamartoma. This case lends support to the proposed neurocristic origin of dermal fibrogenic cells.

The influence of clinical information in the histopathologic diagnosis of melanocytic skin neoplasms

BACKGROUND

We tested the relevance of clinical information in the histopathologic evaluation of melanocytic skin neoplasm (MSN).

METHODS

Histopathologic specimens from 99 clinically atypical MSN were circulated among ten histopathologists; each case had clinical information available in a database with a five-step procedure (no information; age/sex/location; clinical diagnosis; clinical image; dermoscopic image); each step had a histopathologic diagnosis (D1 through D5); each diagnostic step had a level of diagnostic confidence (LDC) ranging from 1 (no diagnostic certainty) to 5 (absolute diagnostic certainty). The comparison of the LDC was employed with an analysis of variance (ANOVA) for repeated measures.

FINDINGS

In D1 (no information), 36/99 cases (36.3%) had unanimous diagnosis; in D5 (full information available), 51/99 cases (51.5%) had unanimous diagnosis (p for difference between proportions <0.001). The observer agreement expressed as kappa increased significantly from D1 to D5. The mean LDC linearly increased for each observer from D1 through D5 (p for linear trend <0.001). On average, each histopathologist changed his initial diagnosis in 7 cases (range: 2-23). Most diagnostic changes were in D2 (age/sex/location).

INTERPRETATION

The histopathologic criteria for the diagnosis of MSN can work as such, but the final histopathologic diagnosis is a clinically-aided interpretation. Clinical data sometimes reverse the initial histopathologic evaluation.

Case of congenital esophageal stricture by ganglioneuroma and acro-flexural hyperpigmentation: a coincidence?

Congenital hyperpigmentation in the acro-genital area and simultaneous occurrence of ganglioneuroma in the esophagus have yet to be reported. Herein, we report a 4-month-old girl presenting with feeding difficulty by esophageal ganglioneuroma and symmetrically distributed brown pigmented patches on the lips, axillae, dorsa of fingers and toes, and genital area. Although the esophageal stricture was resolved by surgical removal of ganglioneuroma, her skin manifestations remained for over 2 years.

Cutaneous ganglioneuroma

Primary cutaneous ganglioneuroma is an extremely rare tumor. We report a case of solitary cutaneous ganglioneuroma on the back of a 75-year-old woman.

Genetic alterations in melanocytic tumors

In the last decade, significant progress has been made in our understanding of the genetic alterations in melanocytic tumors. The most exciting finding is the discovery of oncogenic BRAF mutations in both malignant melanoma and melanocytic nevi. This finding indicates that activation of the mitogen-activated protein kinase pathway may be a critical initiating step of melanocytic neoplasia, and that the fundamental difference between melanoma and nevi may lie in the inhibitory machinery for this oncogenic signaling. In addition, different genetic alterations identified in melanomas at different sites and with different levels of sun exposure have been shown, indicating that there are several distinct genetic pathways in the development of melanoma. Different patterns of genetic alterations have also been identified among different kinds of melanocytic nevi. While acquired nevi and small congenital nevi show a high frequency of BRAF mutations regardless of their anatomic localization, the mutations were rare in medium-sized congenital nevi and giant congenital nevi. Spitz nevi show no BRAF mutations, while a subset of cases show HRAS mutations, often associated with a copy number increase of chromosome 11p. The clear differences in genetic aberration patterns have significant clinical implications in the diagnosis and treatment of melanocytic tumors.

Cutaneous ganglioneuroma within a giant congenital nevus

Cutaneous ganglioneuroma has only occasionally been reported in the literature. Cutaneous ganglioneuroma is seen even more rarely in association with a giant congenital nevus. Differential diagnosis includes malignancies, especially melanoma and metastatic neuroblastoma. It is essential to rule out malignancy in a solid lesion within a congenital nevus. The present report is possibly the first relating ganglioneuroma and a congenital nevus to a cervical mass detected during routine prenatal ultrasound.

Ectopic neural and neuroendocrine neoplasms

Although neural and neuroendocrine tissues are distributed virtually ubiquitously throughout the body, the occurrence of selected neoplasms related to those lineages is extremely uncommon in some topographic sites. This review considers the clinicopathologic characteristics of heterotopic pituitary adenomas; neuroendocrine carcinomas in non-organ-based locations; ectopic (extraneuraxial) meningiomas and gliomas; visceral neuroblastic neoplasms and primitive neuroectodermal tumors; and paragangliomas arising outside the sympathoadrenal neural network. Practical approaches to differential diagnosis are emphasized.

Two case reports of rare fetal tumors: an indication for surface rendering?

Fetal tumors are rare and can be difficult to diagnose in utero. This report describes one case of an extrarenal rhabdoid tumor and one case of a giant congenital melanocytic nevus. Both presented with moderate polyhydramnios and were prenatally detected at 31 weeks of gestation with two-dimensional ultrasound. The application of the surface mode of three-dimensional ultrasound improved the visualization of these tumors especially for the parents and the multidisciplinary team. Three-dimensional sonography proved to be a valuable addition to the prenatal armamentarium for the evaluation of these fetal tumors although it is not mandatory for their assessment and clinical management.