Calvarial malignant melanotic neuroectodermal tumour of infancy presenting with widespread intracranial metastasis

Clinical and imaging features of melanotic neuro-ectodermal tumor of infancy of the maxillary bone: report of four cases and review of the literature

Melanotic neuro-ectodermal tumor of infancy (MNTI) is an extremely rare tumor. The purpose of this study was to describe the imaging features of maxillary bone MNTIs and introduce the key points for clinical diagnosis of MNTI. We retrospectively reviewed four patients with histology-proven MNTIs arising from the maxillary bone. All patients underwent ultrasonic inspections, CT and/or MR scanning. Combined with previously literature, the imaging features were comprehensively evaluated and analyzed. All MNTIs showed a firm, non-ulcerated rapidly-growing soft-tissue swelling with pigmented (blue-colored or black-colored or gray-colored) mucosa. The onset ages were younger than 6 month-old. CT images showed osteolytic or expansive bone destruction of the involved maxillae, fragmentary cortical bone, "free-floating" tooth germs, with or without spiculated/sunburst periosteal reaction. The tumor appeared lightly hyper-intense on T2-weighted sequences, while isointense or lightly hypo-intense or lightly hyper-intense signal on T1-weighted sequences. Enhanced images all displayed heterogeneous enhancement. No metastasis features of lymph nodes or abdominal organs were demonstrated by cervical and abdominal ultrasonic inspections. As a conclusion, accurate recognition of the imaging features of MNTI combined with history and clinical manifestations (early infancy, painless, firm, pigmented mucosa, non-ulcerating lesion) can provide clues for diagnosis of this rare entity.

The Role of Chemotherapy in Management of Inoperable, Metastatic and/or Recurrent Melanotic Neuroectodermal Tumor of Infancy-Own Experience and Systematic Review

Simple Summary

Melanotic Neuroectodermal Tumor of Infancy (MNTI) is a very rare neoplasm that most commonly develops within maxilla in infants. It usually has a benign clinical course and is treated with only surgery. However, patients with large, inoperable, metastatic or multiply recurring MNTI may require systemic treatment. The role of pre- and post-surgery chemotherapy (CHT) in the management of MNTI is unclear. Here, we have presented the disease courses and outcomes of four infants treated with multidrug CHT due to inoperable/recurrent MNTI. Additionally, a systematic literature review was performed which revealed 38 similar cases in the last 42 years. Most children with primarily inoperable MNTI responded to CHT, which allowed physicians to perform complete, non-mutilating delayed surgery. However, it is still uncertain whether CHT administered after incomplete resection of MNTI prevents recurrence. This study aimed to contribute to the establishment of standards of management in patients with inoperable, metastatic or persistently recurring MNTIs, which are currently lacking.

Abstract

Melanotic Neuroectodermal Tumor of Infancy (MNTI) is a very rare pediatric neoplasm of neural crest origin. In most cases, it develops in infants as a localized tumor of the maxilla, and surgery is usually curative. In less than 10% of patients with inoperable, metastatic or persistently recurring MNTI, chemotherapy (CHT) may be considered; however, its role is still unclear. The aim of our study was to assess the efficacy of CHT in children with large, inoperable, metastatic and/or recurrent MNTI. Four such infants, treated with CHT in Polish and German centers of pediatric oncology, were presented. Additionally, a systematic literature search of the PubMed/MEDLINE, Scopus and Web of Science databases was performed, yielding 38 similar cases within the last 42 years. Neoadjuvant CHT, based mainly on the protocols for neuroblastoma, was often effective, allowing for complete delayed surgery in most cases. However, the role of adjuvant CHT in preventing recurrences after incomplete resection of MNTI remains unclear. Disseminated inoperable MNTI was almost universally associated with poor response to CHT and unfavorable outcome. Further investigations to elaborate standards of management in patients with inoperable, metastatic or persistently recurring MNTIs are necessary to improve outcomes.

Calvarial Melanotic Neuroectodermal Tumor of Infancy with Rhabdomyosarcomatous differentiation-A Rare Case

BACKGROUND

Malignant neuroectodermal tumor of infancy is a rare neural crest cell-derived neoplasm of infants. Histologically, melanotic neuroectodermal tumor of infancy usually consists of 2 types of cells: neuroblast-like and melanocyte-like cells. Here we present a rare case of melanotic neuroectodermal tumor of infancy containing a third type of cell population, that is, rhabdomyoblasts in addition to the above two.

CASE DESCRIPTION

We report a case of a 10-month-old female child who was brought to us with complaints of swelling over the right forehead for the last 9 months, which started increasing in size rapidly 3 months before presenting to us. Noncontrast computed tomography scan showed a large well-defined extra-axial lesion in the right frontotemporal region. The child underwent an open biopsy under general anesthesia. Histopathological sections showed a malignant small round cell tumor consisting of hyperchromatic cells lying in sheets and lobules separated by fibrous septae. The patient underwent 7 cycles of neoadjuvant chemotherapy over a period of 2 months. The patient underwent right frontotemporal craniotomy and gross total excision of the lesion as a definitive surgery. Postoperatively, the patient was stable, and there was no new deficit. Histopathology revealed neuroblast-like and melanocyte-like cells with rhabdomyosarcomatous differentiation. The patient received chemotherapy in the postoperative period. The patient had recurrence of the tumor and died 8 months after the surgery.

CONCLUSIONS

Calvarial malignant neuroectodermal tumor of infancy with rhabdomyosarcomatous differentiation is a rare entity with no cases being reported before. Neoadjuvant chemotherapy with surgical excision can be a promising modality of treatment.

The recurrence of the melanotic neuroectodermal tumour of infancy: an unusual presentation of a rare tumour

The melanotic neuroectodermal tumour of infancy (MNTI), also known as melanotic progonoma, is a rare neoplasm derived from neural crest cells. Although it is fundamentally benign, the tumour may present a locally aggressive behaviour, characterised by a rapid progression and a destructive invasion of adjacent structures, hence causing deformities. Unfortunately, perhaps due to the low incidence of this type of tumour, the published cases in the literature do not characterise the factors that imply the malignant or recurrent behaviour of the disease, nor the therapy to conduct these cases. Here, we report a rare case of a recurrent benign MNTI, approached unusually with a favourable outcome.

Melanotic neuroectodermal tumor of infancy arising from the skull: report of an unusual case, review of the literature, and a diagnostic approach

INTRODUCTION

Melanotic neuroectodermal tumor of infancy is a rare neoplasm mainly seen in children under 1 year of life. The most common location of the tumor is the maxilla followed by the cranial vault. Surgery is the treatment of choice and outcome mainly depends on extent of resection.

OBJECTIVES

To report an atypical case of an 8-year-old patient with a melanotic neuroectodermal tumor of infancy, to review the cases with melanotic neuroectodermal tumor of infancy arising from the skull published over the last 13 years, and to provide a diagnostic approach that may allow recognition of a pattern in these rare neoplastic lesions.

METHODS

A case is reported with a description of the clinical, radiological, surgical, and histopathological features. Additionally, the literature was reviewed to identify reports of patients with melanotic neuroectodermal tumor of infancy arising from the cranial vault and all cases published in PubMed over the last 13 years were included. Only studies that evaluated clinical, radiological, surgical, and histopathological findings were included.

CONCLUSION

Melanotic neuroectodermal tumor of infancy is a rare entity that may present with unusual features, but nevertheless has an identifiable pattern that allows the tumor to be considered in the differential diagnosis of intracranial space-occupying lesions in children.

Melanotic Neuroectodermal Tumor of Infancy: a Clinicopathological Case Report

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare neoplasm that affects mainly children under 1 year of age. A 4-month-old boy was referred for evaluation of a lesion with 1 month of evolution. Intra-oral examination detected a firm upon palpation submucosal nodular mass, measuring 1.5 cm in diameter, affecting the anterior maxillary alveolar ridge and covered by a slightly blue mucosa with evident telangiectasia. The patient underwent an incisional biopsy and histological and immunohistochemical analyses revealed nests of AE1/AE3 positive epithelioid cells with abundant melanin pigmentation. Other cell types, resembling neuroblasts, were also present and positive for CD56, synaptophysin and enolase. The diagnosis of MNTI was established and the patient was referred for treatment. Conservative surgical resection was performed along with 3 adjacent teeth under general anesthesia. The patient is in follow-up for 1,5 year without recurrence. Conservative surgical management of MNTI may be an alternative to maxillectomy, contributing to the patient´s quality of life.

Aggressive histologic features do not predict biologic behavior in melanotic neuroectodermal tumor of infancy

While generally benign, occasional aggressive histologic features in the melanotic neuroectodermal tumor of infancy (MNTI) have been used to justify a diagnosis of malignancy; this could lead to overtreatment. We report a case with presumed aggressive histologic features that did not recur following conservative treatment. This adds evidence that histologic features are not predictive of clinical behavior in MNTI.

Melanotic Neuroectodermal Tumor of Infancy with Involvement of the Superior Sagittal Sinus

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare lesion that typically manifests in the first year of life, most commonly involving the facial bones. We present 2 infants with MNTI involving the posterior skull with associated compression of the superior sagittal sinus (SSS). A review of the anatomical locations of MNTI is offered, and the implications of SSS involvement are described. This represents the first known description of MNTI with involvement of the posterior SSS.