Melanotic Neuroectodermal Tumor of Infancy: A Systematic Review

Melanotic Neuroectodermal Tumor of Infancy in the Epididymis: A Case Report

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, benign neoplasm of neural crest origin that predominantly involves the craniofacial region, involvement of the epididymis being extremely rare, with about 30 cases reported. We report an unusual case of a 5-month-old male with MNTI in the epididymis. The patient underwent orchiectomy. Half a year later, there was no sign of recurrence. Whether preoperative examination or intraoperative frozen examination, the tumor may easily be misdiagnosed as malignancy. Melanotic neuroectodermal tumor of infancy should be included in differential diagnosis in infants presenting with fast-growing scrotal swelling.

Melanotic Neuroectodermal Tumor of Infancy of Jaws: A Case Report and Review of Literature

Melanotic neuroectodermal tumor of infancy (MNTI) is an uncommon pigmented neural crest tumor primarily found in infants. We presented a case report of successful surgical management of MNTI in an 11-month-old female. A total of 178 articles discussing 249 cases of MNTI were identified through literature search. Literature review of 250 cases of MNTI including the current case report was conducted considering study parameters such as age and gender of the patient, location of the lesion, levels of vanillylmandelic acid, management options, and outcome after treatment. Statistical review of the data showed that MNTI predominantly affects the anterior maxilla in infants less than six months of age. Recurrence of the lesion shows a significant association with age of the individual and treatment method employed. This study reports a 2.4% mortality rate, 2% malignancy rate, and a recurrence rate of 15.2%, with recurrence times ranging from 15 days to 20 months. We advocate a minimum follow-up of four months to two years to monitor recurrence.

Long term follow-up results of enucleation as the definitive treatment for melanocytic neuroectodermal tumour of infancy and a review on its treatment

Introduction

Melanotic Neuroectodermal tumour of Infancy (MNTI) is a rare entity of pigmented neoplasms of head and neck region. It predominantly occurs within the first year of life. The authors present enucleation as the definitive surgical treatment, with reference to the five departmental cases of MNTI with no recurrence at 5years and 1year of follow-up of other 4 cases.

Case presentation

Five cases of MNTI (age group of 2.5months-7 months) presented to our department as a large bluish-brown non tender swelling protruding into the oral cavity. Radiologic imaging revealed a well-circumscribed solid-cystic enhancing lesion causing elevation of orbit and nasal obliteration in maxillary region and causing buccolingual expansion in mandible. The tumor was enucleated without any bony margin. Histopathological and immunohistochemical evaluation (EMA, Pan Cytokeratin, HMB45, S100, p53, ki67) were done. Patients were followed up at regular intervals and had no recurrence at mean 3years follow-up. A detailed mention of surgical pearls, differential diagnosis and a brief literature review are also done.

Conclusion

MNTI is a pigmented neoplasm that occurs in infants and in head and neck region mostly involves the upper alveolus and maxilla, followed by skull and mandible. Incisional biopsy is needed to confirm the tumour and rule out other malignant round cell tumours. Enucleation of the lesion is necessary without the need for any extra bony margin removal. Close long term follow up is necessary. Conservative surgical approach is usually the best first choice for MNTI treatment.

A case report of melanotic neuroectodermal tumor of infancy complicated with congenital heart disease and hypothyroidism

To the best of our knowledge, thus far there are no reported cases of melanotic neuroectodermal tumor of infancy (MNTI) with multiple complications. In this case report, we describe the clinical phenotype of MNTI in a 9-month-old female infant associated with tetralogy of Fallot (TOF), a congenital heart defect, and congenital hypothyroidism (CH). Our study showed that the growth of MNTI was delayed by a lower dosage of levothyroxine (L-T4) that was prescribed to treat CH because of the presence of TOF, a severe congenital heart disease. However, the standardized dosage of L-T4 improved thyroid function but stimulated the rapid growth of MNTI. Our report demonstrated that treatment with L-T4 affects the progression of MNTI. Our findings demonstrated the role of thyroid hormone in MNTI growth and progression. Furthermore, our study suggested that the treatment of co-morbidities in children with MNTI requires careful consideration of their effects on the growth and progression of MNTI.

Early Class III Treatment Using a Hybrid Rapid Palatal Expander and Facemask in a Patient with Partially Edentulous Maxilla Post MNTI Removal: A Case Report

This case report describes the orthodontic treatment of a 9-year-old girl who presented with multiple agenesis, maxillary contraction, and skeletal Class III malocclusion after the surgical removal of a melanocytic neuroectodermal tumour of infancy (MNTI) or the so-called melanocytic progonoma at 40 days of age. The lack of dental anchorage in the posterior segment of the second quadrant and the search for maximum control during suture expansion to reduce dental effects led to the use of a hybrid rapid palatal expander (RPE) with dental anchorage in the first quadrant and skeletal anchorage on the two miniscrews placed in the second quadrant, to allow a more even distribution of expansion forces. The expansion procedures performed with the hybrid anchorage device and extraoral traction demonstrate the possibility of solving the contraction in the posterior segments and anterior crossbite in a few months with maximum control of the applied forces, despite the objective difficulties related to the specificity of the case.

Melanotic neuroectodermal tumor of infancy: Case report and literature review

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare benign tumor. Here, we report the diagnosis and treatment of 1 case of MNTI in the maxilla and discuss its clinical and pathological features, imaging features, treatment, and prognosis.

Melanotic neuroectodermal tumor of infancy (MNTI) - A rare entity

Melanotic neuroectodermal tumor of infancy is a rare pigmented pediatric tumor seen at craniofacial sites with the most common site being maxilla. This tumor arises from neural crest origin with a polyphenotypic expression of epithelial, neuroblastic, and melanotic markers. It is a locally aggressive tumor with rapid, expansile, and destructive growth. The tumor has fairly high chances of recurrence and malignant transformation, if not diagnosed and treated with time. There is no standard protocol for management owing to its rarity. Hereby, we present one such case of a 2-month-old male child with rapidly enlarging upper jaw swelling. The patient was treated with wide local excision, followed by two cycles of chemotherapy. The patient is in follow-up and doing well with no evidence of any local recurrence or metastasis till date.

Mandibular Melanotic Neuroectodermal Tumor of Infancy: Interdisciplinary Treatment from 2 Months to 19 Years of Age

Melanotic neuroectodermal tumor of infancy (MNTI) is a clinically distinctive, benign neoplasm of neural crest origin. The tumor develops usually in the anterior maxilla and rarely in the skull and mandible. This is a report of the interdisciplinary treatment of a rare case of MNTI occurring in the mandible. The patient was initially addressed for examination at the age of 2 months with a rapidly growing tumor of the mandible that had increased double in size in a week. A well-defined lesion in the left mandible shown on MRI and high urine vanillylmandelic acid (VMA) level determined the diagnosis. The complete interdisciplinary treatment included four interventions. Surgery with enucleation and curettage, performed as first intervention, at the age of 2 months. The second intervention lasted from age 7 to age 15 and included a first phase of Orthodontic treatment to monitor normal growth, followed by interceptive Orthodontic treatment and Prosthodontic intervention with interim dentures. The third intervention accomplished after competition of growth and included the pre-prosthetic surgery with an augmentation of the height of the edentulous atrophic mandible and placement of 4 implants. In the fourth intervention the permanent prosthodontic restoration supported by implants was applied.

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.

Melanotic neuroectodermal tumor of infancy in the mandible: A case report

RATIONALE

Melanocytic neuroectodermal tumor of infancy (MNTI) is a rare benign pigmented neoplasm that arises from the neural crest and has an aggressive growth pattern. It is predominantly seen in infants under 1 year of age, and the most common site of involvement is the maxilla. The currently accepted treatment is removal by surgical resection. Herein, we report a case of MNTI that involved the anterior alveolar ridge of the mandible in a 6-month-old infant.

PATIENT CONCERNS

A case of a 6-month-old male child with a huge mass in the anterior alveolar ridge of the mandible.

DIAGNOSIS

The tumor was diagnosed using histopathological and immunohistochemical techniques on the biopsy specimen obtained following incisional biopsy. Based on the findings, a final diagnosis of MNTI was established.

INTERVENTIONS

Radical resection of the tumor was performed, after determining the extent of resection by referring to the mandibular 3D model created using the pre-operative CT data.

OUTCOMES

The postoperative course was uneventful, and no recurrence has been observed to date for more than 4 years after surgery.

LESSONS

This case emphasizes that early diagnosis and radical surgery are critical to the effective treatment, as MNTI exhibits rapid and destructive growth. It also requires careful and close follow-up because of high recurrence rates.

Atypical scrotal masses: Surgical surprise

We present three unusual cases of atypical scrotal lesions in children. The first was a firm left scrotal mass with the testis indistinguishable. The second with apparently a large hydrocoele, which was a cyst, and the third with multiple nodular lesions, pushing the left testis into the right hemiscrotum. These turned out to be a pigmented neuroectodermal tumour, a lymphatic malformation and neurofibromas respectively. Paediatric surgeons should be aware of such surgical surprises.

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.

Melanotic Neuroectodermal Tumor of Infancy: A Clinicopathological and BRAF V600E Mutation Study of 11 Cases

Purpose

To investigate the clinicopathological features and BRAF V600E mutation of melanotic neuroectodermal tumor of infancy (MNTI).

Materials and Methods

Eleven cases of MNTI diagnosed at the Department of Oral Pathology were collected. Clinicopathological characteristics were obtained from the medical records. Immunostaining was performed by immunohistochemistry (IHC). Amplification-Refractory Mutation System-qPCR (ARMS-qPCR) and Sanger Sequencing were used to detect BRAF V600E mutation.

Results

Of the 11 cases, 3 cases were female and 8 cases were male. The mean age of the first symptoms was 3.2 months (range: 1 to 6 months). Ten cases (90.9%) located in maxilla but only one (9.1%) in mandible. Most of the cases demonstrated well-defined mass with lytic bone destruction and tooth germ affecting radiologically. Histologically, MNTI was consisted of large polygonal melanin-producing epithelioid cells and small round neuroblast-like cells which arranged in irregular alveolar, tubuloglandular and fissured architecture. The epithelioid cells expressed Vim, Pan-CK, NSE and HMB45, while the smalls cells expressed Syn, NSE and scattered Vim. Most cases showed low Ki-67 index (range: <1% to 50%). None of the MNTI cases showed BRAF V600E mutation. Most cases were treated with enucleation (45.4%) or curettage (36.4%). Among the 11 cases, 6 cases had follow-up information, and 2 cases had recurrence lesions after surgery.

Conclusion

MNTI, an extremely rare tumor, mainly affects male infants with strong preference for maxilla. Distinct histopathological features and immunohistochemical profile are helpful to distinguish from other melanin-containing tumors and small round cell tumors. No BRAF V600E mutation in MNTI is detected in the present study and needs further investigations. The factors that contribute to the local recurrence of MNTI are controversial, but the close follow-up for the patients is recommended.

Odontogenic and Developmental Oral Lesions in Pediatric Patients

This article reviews odontogenic and developmental oral lesions encountered in the gnathic region of pediatric patients. The process of odontogenesis is discussed as it is essential to understanding the pathogenesis of odontogenic tumors. The clinical presentation, microscopic features, and prognosis are addressed for odontogenic lesions in the neonate (dental lamina cysts/gingival cysts of the newborn, congenital (granular cell) epulis of the newborn, melanotic neuroectodermal tumor, choristoma/heterotopia, cysts of foregut origin), lesions associated with unerupted/erupting teeth (hyperplastic dental follicle, eruption cyst, dentigerous cyst, odontogenic keratocyst/keratocystic odonogenic tumor, buccal bifurcation cyst/inflammatory collateral cyst) and pediatric odontogenic hamartomas and tumors (odontoma, ameloblastic fibroma, ameloblastoma, adenomatoid odontogenic tumor, primordial odontogenic tumor). Pediatric odontogenic and developmental oral lesions range from common to rare, but familiarity with these entities is essential due to the varying management implications of these diagnoses.

Melanotic Neuroectodermal Tumor of Infancy (MNTI) and Pineal Anlage Tumor (PAT) Harbor A Medulloblastoma Signature by DNA Methylation Profiling

Simple Summary

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare tumor of uncertain origin, morphologically overlapping other rare neoplasms such as pineal anlage tumor (PAT) and a subset of medulloblastomas (i.e., melanotic medulloblastoma). Despite the similarities with MNTI, their possible histogenetic relationship has been traditionally disregarded based on their aggressive behavior and dismal prognosis. The aim of this study was to further characterize the molecular features of MNTI and PAT based on DNA-methylation and copy number variation profiling analysis. We found that MNTI shares a methylation profile with group 3 high-risk medulloblastoma, and potentially with PAT, suggesting a common histogenesis. Most MNTIs in our series lacked copy number variation alterations, whereas their presence in the one PAT deserves further study in larger cohorts to better determine their impact in prognosis and biologic behavior.

Abstract

MNTI is a rare tumor of indeterminate histogenesis and molecular signature. We performed methylation and copy number variation (CNV) profiles in patients with MNTI (n = 7) and PAT (n = 1) compared to the methylation brain tumor classifier v11b4 (BT-C) and the medulloblastoma (MB) classifier group 3/4 v1.0 (MB3/4-C). The patients’ mean age was 8 months (range: 4–48). The BT-C classified five MNTIs and one PAT (relapse) as class family MB-G3/G4, subclass group 3 (score: >0.9). The remaining two MNTIs and PAT (primary) were classified as class family plexus tumor, subclass pediatric (scores: >0.45). The MB3/4-C classified all MNTIs as high-risk MB-G3, Subtype II (score: >0.45). The primary PAT was classified as subtype III (score: 0.99) and its relapse as subtype II/III. MNTI and PAT clustered close to MB-G3. CNV analysis showed multiple rearrangements in one PAT and two MNTIs. The median follow-up was 54 months (four MNTIs in remission, one PAT died). In conclusion, we demonstrated that MNTI shares a homogenous methylation profile with MB-G3, and possibly with PAT. The role of a multipotent progenitor cell (i.e., early cranial neural crest cell) in their histogenesis and the influence of the anatomical site, tumor microenvironment, and other cytogenetic events in their divergent biologic behavior deserve further investigation.

Melanotic Neuroectodermal Tumor of Infancy at Skull: Rare and Rapid-Growing Tumor but Histologically Benign

INTRODUCTION

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare and rapid-growing tumor. However, a neurosurgeon should not overlook this entity when differential diagnosing rapid-growing skull tumor because its histology nature is just benign, and the prognosis is much better than other malignant tumors.

CASE PRESENTATION

We reported the case of a 5-month old male presenting with progressive rapid-growing skull tumor which became 10 cm in diameter in only 5 months compared to the normal head circumference at birth. At first, we thought of malignant skull tumor and performed only biopsy to establish diagnosis. But, when the pathology revealed benign MNTI, we performed preoperative tumor embolization and then radical surgery. Good result was observed.

DISCUSSION

Skull MNTI is the second most common location after the maxilla. Even advanced imaging nowadays cannot distinguish MNTI from other malignant tumors definitely. Urgent biopsy is recommended to establish diagnosis of this benign tumor first. Preoperative angiography with tumor embolization is recommended when feasible, followed by craniotomy with radical resection.

Melanotic neuroectodermal tumor of infancy successfully treated with metformin: A case report

RATIONALE

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare tumor originated from neural crest cells with the potential for recurrence and metastasis. The peak age for the disease is during the first year after birth. The current therapy is primarily surgery. The patient reported here is the first case of MNTI treated with metformin.

PATIENT CONCERNS

A case of a 4-month-old infant with a history of swelling in the mouth for 1 month.

DIAGNOSIS

The tumor was diagnosed using radiology, pathology, and immunohistochemistry, and it was performed with complete surgical resection. Unfortunately, the tumor recurred 3 months after surgery.

INTERVENTIONS

We prescribed metformin for the infant.

OUTCOMES

Currently, after 9 months of treatment, the tumor is well controlled without apparent side effects.

LESSONS

The case presented suggested that metformin may be an underlying therapy for MNTI.

Pigmented Lesions

Oral pigmented lesions have a wide range of clinical presentations, some of which correlate with cutaneous pigmented lesions. This article highlights these correlates and underscores important differences that can potentially have clinical impact. Moreover, given a nonspecific presentation of an oral pigmented lesion, the article provides a reference to aid clinicians with differential diagnoses based on clinical features. This article is an overview of pigmented lesions of the oral cavity, including localized reactive pigmented lesions, neoplastic pigmented lesions, and pigmented lesions as sequelae of a systemic disease.

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 to the skull: case-based review

BACKGROUND

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare tumor, which usually occurs in infants under the age of one. Early diagnosis and radical surgery seem to be critical for long-term cure.

CASE PRESENTATION

We describe a case of a 4-month-old boy with a MNTI to the skull. The mass was first noticed at 4 month of age and grew very rapidly over a time of 2 weeks. Initially, a fine needle biopsy ruled out a sarcoma and led to the diagnosis. The tumor originated from the sphenoid wing and infiltrated the frontotemporal bone, the lateral wall of the right orbit, and the underlying dura mater. A total excision of the tumor, including the adjacent bone and dura, was achieved. Reconstruction of the bone was performed using absorbable plates and Tutobone. Histology confirmed the initial diagnosis, while molecular diagnosis showed high conformity of the MNTI with medulloblastoma group 3. The patient recovered well, while the reconstruction led to a good cosmetic result. A local recurrence occurred leading to a single-dose chemotherapy with Vincristine and a second surgery after 15 weeks. Thereafter, the patient developed recurrent large pseudomeningocele, which was treated by multiple shunt procedures and finally reconstruction of the bone using Palacos. Radiological follow-up 3 months after the second resection showed no tumor recurrence.

CONCLUSION

Radical surgery for MNTI is to date the gold standard since it seems to minimize recurrence rates. Because of the rapid and destructive growth within the bone, reconstruction is necessary, which can be very challenging in infants.

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 Tumour of Infancy: Clinical Courses and Therapeutic Options-A Review of Three Cases

Background

Melanotic neuroectodermal tumour of infancy (MNTI) is a rare benign neoplasm. MNTI appears most often during the first year of life, arises predominantly in the maxilla and tends to recur. We discuss possible therapeutic options given in the literature and within our experience in three cases.

Patients

In our recent case, we used an intraoral approach to perform resection of the right-sided maxilla. Despite tumour-positive margins, there was no recurrence over the course of one year. In a previous case of MNTI, two recurrences occurred and 6 months after last resection patient received a rib graft for maxillary reconstruction. However, at the age of 7 years, the infant displayed severe maxillary hypoplasia. In a third case of MNTI, the patient was followed up after initial therapy for two decades and underwent multiple reconstruction procedures to achieve successful rehabilitation.

Conclusion

Surgical treatment of MNTI should respect vital anatomic structures to avoid gross mutilation. The need for extended and repetitive tumour resection in early childhood can lead to growth disturbances and to further multiple reconstruction procedures in adulthood. Because of the rarity of MNTI, an international database is warranted to evaluate therapies and clinical courses over decades.

Melanotic Neuroectodermal Tumor of Infancy: A Rare Case Report

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare pigmented neoplasm of neural crest origin that most commonly arises in the maxilla of neonates and infants during the first year of life. We report the case of a three-month-old female child who presented with a 15-day history of intraoral swelling. Radiologically, the tumor was detected in the right maxilla, which was removed by wide local excision. Histopathological examination revealed the biphasic population of cells with melanin pigment deposition. Immunohistochemistry study was done confirming the diagnosis of MNTI.

Melanotic neuroectodermal tumor of infancy in ovary: A rare case report

RATIONALE

Melanotic neuroectodermal tumor of infancy (MNTI) is an extremely rare benign pigmented neoplasm of neural crest origin with rapid expansile growth and a high recurrence rate. It is predominantly found in infants of <1 year of age, involvement of the head-and-neck region is the most common presentation though it is reported at other sites including mediastinum, shoulder, thigh, foot, epididymis, uterus and ovary. The patient reported here is the third case of MNTI presenting in an ovary, and the first reported in the infant ovary.

PATIENT CONCERNS

A 33-month-old girl was presented to our unit for a huge abdominal mass.

DIAGNOSIS

MNTI was eventually diagnosed by histological manifestations supplemented with immunohistochemical findings.

INTERVENTIONS

Exploratory laparotomy and complete resection were conducted successfully.

OUTCOMES

Postoperative course was uneventful and no recurrence was displayed in the 6-month follow-up.

LESSONS

This case emphasizes that pediatric surgeons and pathologists must always consider the possibility of MNTI while dealing with ovarian neoplasms in infants. Although considered to be a benign tumor, proper treatment and close clinicoradiological follow-up of this tumor are of great importance.

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.

Melanotic neuroectodermal tumour of infancy: Refining the surgical approach

Melanotic neuroectodermal tumours of infancy (MNTI) are particularly rare and although predominantly benign, are infiltrative and locally aggressive. Presenting in the first year of life, prompt diagnosis and effective management are critical in minimizing morbidity and the risk of recurrence. A retrospective review of 11 MNTI managed at Great Ormond Street Hospital (GOSH) from 2000 to 2017 was undertaken. Eight tumours presented in the maxilla, two in the skull and one in the mandible. The primary modality of treatment was surgery in 10 cases with one patient receiving neoadjuvant chemotherapy. In spite of microscopically incomplete resection in seven cases, only three recurred. Overall, there was a local recurrence rate of 27% with no distant metastases noted. Disease-free survival was 100% with a follow-up ranging from 0.75 to 17 years (median 5 years). Taking our results in conjunction with the available literature, there is a role for conservative initial surgery of MNTI and this should be coupled with delayed reconstruction and intensive short-term follow-up. We propose an adapted treatment algorithm that aims to balance the risk of recurrence and malignant change with surgical morbidity in an infant population.

A retrospective study of oral and maxillofacial pathology lesions diagnosed at the Faculty of Dentistry, King Abdulaziz University

Background

Oral and maxillofacial lesions (OMFL) comprise a broad spectrum of benign and malignant lesions that affect the oral cavity. However, few epidemiological studies have evaluated oral cavity lesions, and very few have focused on oral soft tissue pathology. The purpose of this study was to identify the prevalence and distribution of OMFL that had been diagnosed histologically at the Oral Pathology Laboratory, Faculty of Dentistry, King Abdulaziz University.

Materials and methods

A retrospective study was conducted to assess the distribution of OMFL among the oral cavity biopsies submitted to the Oral Pathology Laboratory during the period from 1996 to 2016. Information on sex, age, location of the lesion, and histopathologic diagnosis was analyzed.

Results

A total of 1,218 cases were examined. Among these, reactive/adaptive lesions were the most common type (n=245; 20.1%) and cystic lesions were the second most common (n=214; 17.6%), followed by inflammatory lesions (n=152; 12.5%) and epithelial pathology (n=115; 9.4%).

Conclusion

The results of the present study provide valuable information on the prevalence of OMFL in Jeddah, Saudi Arabia. Reactive conditions were the most frequently diagnosed pathologies. Most oral and maxillofacial biopsies were soft tissue lesions, benign in nature, and inflammatory in origin. Further studies are necessary to provide more information on head and neck diseases in the general population to develop better future oral health policies.

Black and Brown Oro-facial Mucocutaneous Neoplasms

Black and brown-colored mucocutaneous lesions present a differential diagnostic challenge, with malignant melanoma being the primary clinical concern. The vast majority of pigmented lesions in the head and neck region are the result of benign, reactive factors such as post-inflammatory melanosis. However, it is not uncommon to discover a range of muco-cutaneous black and brown neoplasms in the oro-facial area. The majority of black/brown pigmented neoplasms are melanocytic in origin; these are neoplasms of neural crest derivation. Melanocytic nevi are a diverse group of benign neoplasms that are the result of specific oncogenic mutations. They are common on cutaneous surfaces but can manifest in mucosal sites. Currently, nevi are classified based on clinical and histological criteria. The most common cutaneous and oral mucosal nevus is the acquired melanocytic nevus; nevi do not pose an increased risk for the development of malignant melanoma. Emerging information on specific genetic differences supports the notion of biologically distinct nevi. This article will review the classic clinical and microscopic features of nevi commonly found in the head and neck region, and discuss emerging concepts in nevus pathogenesis and taxonomy. Melanoma is a malignant melanocytic neoplasm and is a result of cumulative genetic deregulation. The etiology of malignant melanoma (MM) is multifactorial and includes underlying genetic susceptibility, UV radiation, skin-type, and race. The majority of MM occurs on cutaneous surfaces and less commonly on mucosal and extra-cutaneous visceral organs. Regardless of location, MM exhibits clinical-pathological features that relate to horizontal or vertical tumor spread. Cutaneous and mucosal MM typically present as asymmetrical, irregularly bordered, large (> 0.5 cm), heterogeneous brown-black lesions with foci of erythema, atrophy or ulceration. As with melanocytic nevi, advances in melanomagenesis research have revealed primary oncogenic BRAF and NRAS mutations associated with cutaneous MM. Unlike their cutaneous counterparts, mucosal melanomas exhibit primary oncogenic alterations in c-KIT and other genes. This article will discuss the role of specific primary oncogenic and secondary/tertiary genetic defects in differential clinical presentation, anatomic distribution, future classification changes, and targeted therapy of melanoma. The clinical and microscopic features of mucosal melanomas and a summary of management guidelines will be discussed. Additionally, this article will cover the salient features of melanocytic neuroectodermal tumor of infancy, a neoplastic entity that can involve the oro-facial region, and the clinical-pathological features of selected, commonly occurring pigmented ectodermally-derived neoplasms that are often part of the clinical differential diagnosis of black-brown pigmented lesions.

Spontaneous Regression of Diffuse Periosteal Melanotic Neuroectodermal Tumor of Infancy in the Tibia, With 13-Year Follow-up

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare entity primarily affecting the craniofacial bones during the first year of life, with only 5 reported cases involving peripheral long bones. We herein present a case of MNTI in the tibia of an infant, with a somewhat atypical presentation, and a noteworthy clinical course characterized by progressive spontaneous resolution without therapy, thus sparing the child the trauma of amputation. There is no evidence of active residual or recurrent disease with 13-year follow-up. To the best of our knowledge, essentially all reported cases of MNTI have received empirical treatment, some at the price of mutilating surgery or fatal chemotherapy. We propose that the necessity of aggressive treatment be evaluated on a case-by-case basis, especially in patients with diffuse periosteal involvement, as in this patient. A trial of watchful waiting can be considered when treatment would involve substantial morbidity or risk of complications.

Epididymal melanotic neuroectodermal tumor of infancy: A rare cause of scrotal mass in an infant

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, benign neoplasm of neural crest origin more commonly seen in the craniofacial region. We report a case of MNTI of the epididymis in a 6-month-old male child with emphasis on the sonographic appearance which has not been previously described. In this case, the mass was inseparable from the testicle and therefore the differential diagnosis considered both extratesticular and intratesticular masses. MNTI should be added to the differential diagnosis of scrotal masses, particularly if they present in a child younger than 12 months of age.

Melanotic neuroectodermal tumor of infancy: A rare entity

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare neoplasm with a predilection for the head-and-neck region. Approximately 472 cases reported in literature till date. We report an unusual case of MNTI in a 1-month old child. A 10 cm × 5 cm × 5 cm nontender, firm, deep-seated swelling was seen involving the right zygomatic and maxillary region. Magnetic resonance imaging was suggestive of rhabdomyosarcoma and immunomorphological assessment of the excision specimen revealed the final diagnosis of MNTI. On follow-up, the patient developed recurrence 4 months after surgery and was reoperated. The present case emphasizes that albeit rare, pediatric surgeons and pathologists must always keep in mind the possibility of MNTI while dealing with maxillofacial tumors in infants. Owing to rather nonspecific clinicoradiological features, histopathology supplemented with immunohistochemistry remains the gold standard for diagnosis. Although considered to be a benign tumor, close clinicoradiological follow-up is strongly recommended given the significant risk of recurrence as highlighted by our case.

Melanotic neuroectodermal tumour of infancy: A report of two cases

•

Shedding light on the aggressive nature and rare incidence of Melanotic Neuroectodermal Tumour of Infancy (MNTI).

•

Detailing different clinical and radiographic features of MNTI.

•

Outlining the management of MNTI and postoperative follow-up regimen.

•

Emphasising the importance of early diagnosis and surgical intervention in Melanotic Neuroectodermal Tumour of Infancy.

Introduction

Melanotic neuroectodermal tumour of infancy (MNTI) is a benign tumour of infancy, most commonly affecting the head and neck region. First described in 1918, less than 500 cases have been reported in the literature. MNTI is aggressive in nature & has a high rate of recurrence.

Presentation of cases

In this retrospective case series, we report two cases of MNTI that presented at our unit; both cases were managed by wide excision and have been followed up uneventfully for over two years.

Discussion

MNTI has a recurrence rate of up to 20%. Patient’s age can play a significant role in recurrence rate. Although this neural crest tumour is somewhat rare in the literature, there is a consensus with regards to surgical management; the gold standard remains to be wide excision with safety margin. Select cases may benefit from adjuvant and neoadjuvant therapy.

Conclusion

Owing to its locally aggressive nature and high recurrence rate, prompt diagnosis and surgical intervention is advised in cases of MNTI. Further understanding of this tumour is needed on a microscopic level in order to determine clear prognostic factors.

Melanotic Neuroectodermal Tumor of Infancy

Context.—

Melanotic neuroectodermal tumor of infancy, albeit rare and generally regarded as benign, is an important tumor to recognize because of its rapid growth, potential for local recurrence, and small round blue cell morphology, which can lead to misdiagnosis of a malignant neoplasm.

Objective.—

To review its clinical presentation and immunomorphologic findings, and discuss common entities in the differential diagnosis.

Data Sources.—

The study involved PubMed searches, including multiple review articles, case studies, retrospective studies, selected book chapters, and University of Michigan cases.

Conclusions.—

Melanotic neuroectodermal tumor of infancy most commonly occurs in the bones of the head and neck region during the first year of life, but it can also present in other locations, including the central nervous system, testes, ovaries, and subcutaneous soft tissues. Histologically, it is composed of a biphasic population of cells, consisting of epithelioid melanin-producing cells and primitive neurogenic cells in a fibrocollagenous stroma. These microscopic findings, especially in small biopsies, can lead to a broad differential diagnosis that includes malignant small round blue cell tumors and malignant melanoma. Melanotic neuroectodermal tumor of infancy commonly has an infiltrative growth pattern, and anatomic constraints often lead to incomplete resection and local recurrence, requiring multiple surgical operations. Because melanotic neuroectodermal tumor of infancy can mimic a more aggressive and aggressively treated malignancy, recognition of this rare tumor is very crucial for pathologists.

Melanotic neuroectodermal tumor of infancy: A rare pediatric head and neck lesion

Melanotic neuroectodermal tumors of infancy are rare tumors arising from the neural crest and typically present during the first 12 months of life. The majority involve the facial bones, although melanotic neuroectodermal tumors of infancy of the skull and extremities have been observed with less frequency, as in the present case. This entity may initially be presented to the dermatologist as a scalp mass and should be considered in the differential diagnosis of infants with rapidly growing head and neck lesions.

Melanotic neuroectodermal tumour of infancy of the jaws: an analysis of diagnostic features and treatment

The purpose of this study was to integrate the available published data on melanotic neuroectodermal tumour of infancy (MNTI) of the jaws into a comprehensive analysis of its clinical/radiological features, with emphasis on the predictive factors associated with recurrence. Eligibility criteria included publications with sufficient clinical/radiological/histological information to confirm the diagnosis. A total of 288 publications reporting 429 MNTI cases were included. MNTIs were slightly more prevalent in males and markedly more prevalent in the maxilla. Most of the lesions were asymptomatic, presenting cortical bone perforation and tooth displacement. Nine lesions were malignant, with metastasis in five cases. Enucleation was the predominant treatment (67.2%), followed by marginal (18.4%) and segmental resection (6.1%). Eighty-one of 356 lesions (22.8%) recurred. Recurrence rates were 61.5% for curettage, 25.3% for enucleation alone, 16.2% for enucleation+curettage, 20.0% for enucleation+peripheral osteotomy, 11.3% for marginal resection, 10.0% for segmental resection, 30.0% for chemotherapy, and 33.3% for radiotherapy. Enucleation and resection presented significantly lower recurrence rates in comparison to curettage. Curettage appears not to be the best form of treatment, due to its high recurrence rate. As resection (either marginal or segmental) is associated with higher morbidity, enucleation with or without complementary treatment (curettage or peripheral osteotomy) would appear to be the most indicated therapy.

Clinical and immunohistochemical study of melanotic neuroectodermal tumor of infancy in the maxilla

Melanotic neuroectodermal tumor of infancy is a rare and fast-growing neoplasm. In this study, we describe the case of a 6-month-old female patient, who presented swelling in the anterior maxilla. Tomographic reconstruction showed an unilocular hypodense and expansive area associated with the upper right central primary incisor. The presumptive diagnoses were dentigerous cyst, adenomatoid odontogenic tumor, melanotic neuroectodermal tumor of infancy and rhabdomyosarcoma, and an incisional biopsy was performed. Microscopically, the lesion revealed a biphasic cell population, consisting of small, ovoid, neuroblastic-like cells and epithelioid cells containing melanin. Immunohistochemically, the melanocyte-like component was strongly and diffusely positive for HMB-45 and Melan-A, but weakly positive for S100. Based on these findings, definitive diagnosis of melanotic neuroectodermal tumor of infancy was established. Then, enucleation of the lesion was performed by careful curettage. After 2 year follow-up, no clinical or radiographical evidence of recurrence was verified. The present case highlights the importance of early diagnosis and therapeutic intervention at the appropriate time to achieve a favorable outcome for the patient.

Prenatal Diagnosis of a Melanotic Neuroectodermal Tumor of Infancy (MNTI): A Case Report With a Favorable Outcome After Chemotherapy Failure and Incomplete Resection

We present the case of a woman referred to our department at 34 weeks of pregnancy with a fetal ultrasonographic scan showing a mass that had developed within the right maxilla with invasion of the orbit. A retrospective examination showed that this tumor had been present since the 12th week of pregnancy. At 39+4 weeks of gestation, a boy was born. He presented a black firm aspect in the maxilla. A computed tomographic scan and magnetic resonance imaging revealed a soft tissue swelling over the right maxilla, extending into the orbit but without invasion of the globe. Surgical biopsy confirmed a melanotic neuroectodermal tumor of infancy. The pathologic examination did not show any neuroblast-like component on the hematoxylin eosin saffron staining. Because of the extension and the size of the lesion, neoadjuvant chemotherapy was carried out. At day 21, the patient received 1 cycle of low-dose cyclophosphamide and vincristine, 2 cycles of etoposide and carboplatin, and thereafter 1 cycle of cyclophosphamide, adriamycin, and vincristin because the lesion kept growing. After stabilization of the size of the tumor, at 4 months, a maxillectomy and partial resection of the orbital floor and lateral orbital wall was performed on the patient. As a complete resection would have required orbital exenteration, surgery was performed deliberately incomplete leaving a macroscopic residue (R2). At 2.5 years of follow-up, the patient showed complete remission with no lesions evident on magnetic resonance imaging.

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.