Melanotic Neuroectodermal Tumor of Infancy: A Case Image

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare benign neoplasm that can be mistaken for malignancies due to its unfamiliarity among clinicians and aggressive clinical appearance. We herein contributed by reporting an additional case of MNTI characterized by an extensive extraoral protrusion in a 2-month-old infant. The lesion involved the anterior maxilla, cheek, and infraorbital region, resulting the displacement of the nose to the contralateral side, and measuring approximately 10 cm in size. Surgical resection of the lesion was performed. After a 6-month follow-up, the patient has shown no evidence of recurrence. The rapid growth and aggressive behavior of MNTI emphasize the importance of an early diagnosis and prompt intervention in order to achieve favorable outcomes.

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.

Melanotic neuroectodermal tumor of infancy: A narrative review of dental aspects

Melanotic neuroectodermal tumors of infancy (MNTI) are a rare type of benign tumor that affects the head and neck region. MNTI represents (68-80%) of the tumors in the maxillary region. This tumor is usually located in the alveolar crest, skull, mandible, and brain. Although this tumor is considered benign, it can grow rapidly, with a high risk of recurrence and interference with functions of infancy, such as feeding and breathing. It is also frequently harmful to the surrounding soft and hard tissues or adjacent sensitive vital structures. This study aimed to review the pathological, clinical presentation, and treatment of melanotic neuroectodermal tumors in infancy and the role of dentists in these cases.

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.

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.

Imaging of Pediatric Testicular and Para-Testicular Tumors: A Pictural Review

Pre- and post-pubertal testicular tumors are two distinct entities in terms of epidemiology, diagnosis and treatment. Most pre-pubertal tumors are benign; the most frequent are teratomas, and the most common malignant tumors are yolk-sac tumors. Post-pubertal tumors are similar to those found in adults and are more likely to be malignant. Imaging plays a pivotal role in the diagnosis, staging and follow-up. The appearance on ultrasonography (US) is especially helpful to differentiate benign lesions that could be candidates for testis-sparing surgery from malignant ones that require radical orchidectomy. Some specific imaging patterns are described for benign lesions: epidermoid cysts, mature cystic teratomas and Leydig-cell tumors. Benign tumors tend to be well-circumscribed, with decreased Doppler flow on US, but malignancy should be suspected when US shows an inhomogeneous, not-well-described lesion with internal blood flow. Imaging features should always be interpreted in combination with clinical and biological data including serum levels of tumor markers and even intra-operative frozen sections in case of conservative surgery to raise any concerns of malignity. This review provides an overview of imaging features of the most frequent testicular and para-testicular tumor types in children and the value of imaging in disease staging and monitoring children with testicular tumors or risk factors for testicular tumors.

Rosette-like formations in melanocytic neoplasms: A case report and literature review

Homer-Wright-like rosettes are a common finding in neural tumors but seldom seen in melanocytic nevi and melanoma. We report a case of a 23-year-old male with a compound melanocytic nevus with such rosette-like structures and summarize the current literature on this histopathological feature in melanocytic neoplasms. A symmetric, well-circumscribed, compound nevus consisting of aggregations of epithelioid melanocytes with eccentric nuclei and central eosinophilic cytoplasm, resembling Homer-Wright rosettes, was present on biopsy. Immunohistochemical stains strongly supported a melanocytic entity and were negative for NTRK1/2/3, a fusion protein potentially associated with rosette-like structures. We found 17 other cases of benign melanocytic nevi, including 9 atypical Spitz tumors and 6 Spitz nevi, and 11 malignant melanomas, including 3 Spitz melanomas and 4 metastases. We observed remarkable diversity among lesion morphologies containing rosettes, as well as level of prominence and cytology of the rosettes themselves. This case illustrates the morphologic malleability of neural-crest-derived lesions to share microscopic and phenotypic attributes.

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 tumour of infancy - A case report and review of literature

Rationale:

Melanotic neuroectodermal tumour of infancy (MNTI) is universally described as a rare, benign, pigmented lesion which most frequently involves the maxilla. Its origin is well established to be in the neural crest cells. Due to the high recurrence rate and aggressive behaviour mimicking malignancy, it poses a great challenge in their diagnosis, treatment planning, and prognosis.

Patient Concern:

Two-year-old female with no known comorbidities was brought in with the chief complaint of a growing swelling in the upper lip region.

Diagnosis and Treatment:

She was taken up for resection of the tumour under general anaesthesia. The specimen was subjected to histological and immunological examination confirming the diagnosis of MNTI.

Outcome:

The postoperative period was uneventful. After regular follow-up, the patient showed satisfactory healing with no signs of recurrence.

Take-Away Lessons:

Based on our experience, we feel that the diagnosis of MNTI is mainly clinical. Early conservative surgical excision and regular follow-up provide an excellent result with good prognosis.

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.

EAU-ESPU pediatric urology guidelines on testicular tumors in prepubertal boys

BACKGROUND

Testicular tumors in prepubertal boys account for 1-2% of all solid pediatric tumors. They have a lower incidence, a different histologic distribution and are more often benign compared to testicular tumors in the adolescent and adult group. This fundamental difference should also lead to a different approach and treatment.

OBJECTIVE

To provide a guideline for diagnosis and treatment options in prepubertal boys with a testicular mass.

METHOD

A structured literature search and review for testicular tumors in prepubertal boys was performed. All English abstracts up to the end of 2019 were screened, and relevant papers were obtained to create the guideline.

RESULTS

A painless scrotal mass is the most common clinical presentation. For evaluation, high resolution ultrasound has a detection rate of almost 100%, alpha-fetoprotein is a tumor marker, however, is age dependent. Human chorionic gonadotropin (HCG) was not a tumor marker for testis tumors in prepubertal boys.

CONCLUSION

Based on a summary of the literature on prepubertal testis tumors, the 2021 EAU guidelines on Pediatric Urology recommend a partial orchiectomy as the primary approach in tumors with a favorable preoperative ultrasound diagnosis.

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.

Rare Diseases of the Orbit

This article provides an overview of rare orbital diseases. Congenital malformations, inflammatory diseases, benign and malignant neoplasias are described. Although it represents a relatively small area of the body the orbit contains multiple different tissues. Therefore, a great variety of diseases can be found within the orbital space. That is the reason, why both the completeness and the level of detail in the description of particular diseases must be somewhat limited. Nevertheless, clinical manifestations, important aspects of diagnosis, treatment strategies, and, when specific data are available, the prognosis are described. The authors tried to highlight the most characteristic aspects of the different diseases to describe their relevant aspects in spite of the brevity of the subsections.

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 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.

Melanotic neuroectodermal tumour of infancy presenting as a lytic lesion in femur: a rare tumour at a rare site with an unusual behaviour

Melanotic neuroectodermal tumour of infancy (MNTI) is an uncommon tumour, predominantly occurring in head and neck, mostly maxilla, but also in skull and mandible. Although a benign lesion, it is known to recur in 15%-27% of cases, and rarely, may undergo malignant transformation. We present a case of a 5-month-old female patient, who presented with a gradually progressive swelling in the right thigh. On imaging, an osteolytic lesion was seen, involving the metadiaphysis of shaft of right femur. A biopsy was performed, on which diagnosis of MNTI was made. MNTI is rarely seen in extremities. To the best of our knowledge, only six cases have been reported in femur, the present case being the seventh. The tumour showed spontaneous regression on follow-up in our patient, which has rarely been described. A knowledge of characteristic morphology and immunohistochemistry is the key to differentiate it from other tumours.

Primitive neuroectodermal tumors: a clinical and radiological analysis of six cases

Background

Primitive neuroectodermal tumor (PNET) is extremely rare and highly aggressive with poor prognosis. Few studies concerning PNET's the imaging features have been published.

Methods

Six cases of PNET, all confirmed by pathology and immunohistochemical (IHC) examinations, were treated during January 2012 to December 2016. These cases' clinical course and imaging findings were retrospectively analyzed.

Results

Among six PNET cases, one located in left superior abdomen, one case at posterior abdominal wall, one case in right orbit, one case in left frontal temporal lobe, one case in pelvic cavity, and one case located in left supraclavicular fossa. The tumor's density was uniform for small tumor and heterogeneous for large tumors on CT images, while the size of tumors differed during presentation depending on the location of the tumor. Marked enhancement was visualized after injection of contrast media. The demarcation between the lesion and adjacent tissues or organs tended to be unclear. On magnetic resonance imaging (MRI) images, the mass mainly showed heterogeneously long T1 and long T2 signal intensity, mixed high signal intensity on fluid-attenuated inversion recovery (FLAIR) image. In two cases maximum intensity projection image reconstruction demonstrates tortuous blood vessels within the tumor on enhanced CT images. Five cases were treated by surgical resection with two cases received adjuvant radiotherapy and three cases received adjuvant chemotherapy. Six patients were followed up with a mean period of 34.5 months (ranging from 6 to 55 months). Five patients survived and one died. Among the five patients undergoing surgeries, one patient presented pelvic and abdominal recurrence/metastasis 2 months after abdominal PNET resection. One patient had a recurrent lesion in the right orbit involving the right ethmoid sinus 6 months after right orbital PNET resection. One patient's pelvic tumor recurred 7 months after PNET operation, and this patient died after 1 year and 10 months of follow-up. During the follow-up period, the remaining three cases did not show obvious recurrence and/or metastasis.

Conclusions

Overall, the imaging appearances of PNET lack characteristics. PNETs generally do not have clear boundary, or partially so, with its adjacent organs or tissues suggesting their invasive nature. Upon further validation, maximum intensity projection image reconstruction demonstrates tortuous blood vessels within the tumor on enhanced CT images may be valuable information for the diagnosis of PNET.