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

Abstract

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.

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

“…Although both latter patients survived, the effectiveness of these regimens is difficult to assess. Various other CHT protocols have been used for inoperable/metastatic MNTI in the last 15 years [22,24,39,45,50,51,54].…”

“…Four of 12 patients did not respond well to neoadjuvant CHT (stable disease in three, PD in one patient), however, in all of those cases, delayed surgeries were attempted [3,53,54]. Three patients survived, and one is currently being treated for late tumor recurrence.…”

“…In total, 6 of 11 patients treated with neoadjuvant CHT due to inoperable and/or metastatic MNTI at diagnosis were disease-free at the time of publication [4,47,48,50,53,54]. One patient is alive with disease (our patient, number 3), two patients died (including one due to acute therapy-related complications) [49,51] and three patients were lost to follow-up [3,43,52].…”

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

“…In the present study, the proportion of these two types of cells varied case by case. When a case was predominant with large epithelioid cells (18) or small neuroblast-like cells (19), immunohistochemistry should be performed to confirm the diagnosis because the two type of cells had distinct immunohistochemical phenotype and some of the markers could indicated the presence of the specific type of the cells. In the current study, both large and small cells expressed NSE and Vim, even though that only few small cells expressed Vim.…”

“…The result was inconsistent with Gomes et al's study, the tumor enrichment prior to DNA extraction in their investigation might partly explain the mutation detection in one case. However, it had been noticed that another two cases in recent publications were also negative for BRAF V600E mutation (18,21). Paraffin-embedded samples could influence the molecular analysis, further studies on molecular alterations should be conducted using fresh or frozen samples, if possible.…”