Primary brain neuroendocrine carcinoma: a case report

¹Radiotherapy Department University Mohamed VI Hospital, Faculty of Medicine and Pharmacy, Mohamed First University Oujda, Oujda, Morocco, ²Oncology Department University Mohamed VI Hospital, Faculty of Medicine and Pharmacy, Mohamed First University Oujda, Oujda, Morocco

^&Corresponding author
Samba Soumiya, Radiotherapy Department University Mohamed VI Hospital, Faculty of Medicine and Pharmacy, Mohamed First University Oujda, Oujda, Morocco

Introduction    

Brain neuroendocrinecarcinomais a rare neoplasm arising from cells of the endocrine and nervous systems. While they can arise in various organs, they are most prevalent in the digestive and respiratory tracts [1]. Neuroendocrine carcinomas are known to develop in all the aforementioned systems; however, very few studies imply that neuroendocrine carcinoma largely originates from the brain due to its rarity [2]. Neuroendocrine cells naturally coordinate the production and release of physiologically active chemicals in response to neurotransmitter stimulation. As a result, neuroendocrine have distinct characteristics, including the ability to secrete physiologically active amines and peptidyl hormones, allowing for their unique identification [3].

The prevalence of neuroendocrine neoplasms (NENs) has shown a notable upward trend throughout the last two decades [4]. The numerical value provided by the user is insufficient to determine the context or subject for a phenomenon is thought to be attributable to the higher rates of detection. Although the frequency of occurrence is on the rise, these tumors remain very rare, constituting about 4%-6% of all malignancies outside the cranial cavity [3,5]. When brain NECs are identified as the initial signs of illness, it's important to rule out extracranial localizations [6]. In this paper, we discuss the case of a previously healthy 22-year-old male patient who was hospitalized with symptoms of intracranial pressure believed to be caused by a primary neuroendocrine carcinoma of the brain. Despite extensive diagnostic work, no additional potential causes of primary tumors were identified.

Patient and observation     

Patient information: a 22-year-old man, a professional worker, with no significant medical history, and no family history of cancer, was consulted following gradually worsening headaches, morning vomiting, and diplopia over the past three months. Symptomatology develops in the context of general state conservation.

Clinical findings: the clinical examination found a patient conscious, and stable in hemodynamic and respiratory terms, the rest of the examination objects no anomaly including the neurological and ganglionary examination.

Diagnostic assessment: a magnetic resonance imaging (MRI) of the brain was performed and revealed a 7.4 cm solitary lesion in the left frontal lobe from the ethmoid region (Figure 1, Figure 2). Then a biopsy of the area between the nostrils was performed. The tissue proliferation consisted of small cells with a high nucleo-cytoplasmic ratio. These cells had hyperchromatic nuclei with distinct nucleoli. The mitotic count was estimated at fifteen mitoses per square millimeter. Initially, the tumor was described as a neuxsqroblastoma, but a referral to a specialized pathology lab described it as more consistent with an NEN. The tissue was strongly positive for synaptophysin and chromogranin, and neurofilament staining was focally positive (Figure 3). Epithelial membrane antigen (EMA), glial fibrillar acidic protein (GFAP), neuronal nuclear antigen (NeuN), S-100, thyroid transcription factor-1 (TTF1), CDX2, and a pancreatic battery including insulin, gastrin, somatostatin, glucagon, vasoactive intestinal peptide (VIP) and pancreatic polypeptide (PP) were all negative, which favored a neuroendocrine carcinoma over neuroblastoma.

Therapeutic interventions: the patient received firstly radiation therapy on brain injury at a total dose of 54 Gy in 30 fractions, then 4 cycles of chemotherapy based on cisplatin and etoposide.

Follow-up and outcomes: radiation therapy and chemotherapy were delivered without major incidents, and monitoring during treatment showed improvement in clinical symptoms including the disappearance of headaches and improvement of diplopia, after 3 months of the end of treatment a radiological evaluation was done by a cerebral scanner (Figure 4) that showed a decrease in the size of the cerebral tumor process in favor of a favorable response; the patient is still alive and good control of his disease.

Patient perspective: the patient was satisfied with the quality of care and therapeutic outcomes.

Informed consent: the patient was informed about the procedure of publishing a research paper and gave consent.

Discussion     

Primary intracranial neuroendocrine carcinomas are extremely rare, and only a few cases have been reported in the literature. No deaths have been attributed to this condition. Most cases are situated in the skull base and sellar regions, with isolated instances in the third ventricle, frontal convexity, parietal lobe, and cerebellum [7]. Neuroendocrine carcinoma can be clinically categorized as functional or non-functional based on hormone production. They can also be categorized by anatomical location and grade. Ki-67, expressed in actively dividing cells, indicates the degree of proliferation. Proper classification of neuroendocrine carcinoma aids in determining diagnostic methods, treatment options, and disease prognosis [8]. The comprehensive evaluation of neuroendocrine neoplasms often involves the use of computed tomography scans and fluorodeoxyglucose positron emissiontomography/computed tomography (FDG PET/CT) scans. The sensitivity of computed tomography (CT) imaging in the detection of a primary tumor in cases with unknown primary neuroendocrine neoplasms (NEN) is reported to be 95% [9].

Our patient hadundergoing brain magnetic resonance imaging (MRI) and whole-body computed tomography (CT) [10]. Based on the pathological characteristics observed in this case, we agree that the differential diagnosis of neuroendocrine tumors (NECs) should encompass esthesioneuroblastoma and ectopic sparsely granulated corticotroph adenoma (SGCA). In our case at first, the medical diagnosis indicated the presence of an esthesio-neuroblastoma, however; further examination of the tissue revealed strong positive results for synaptophysin and chromogranin, with focal positivity for neurofilament staining. These findings suggested the presence of a neuroendocrine carcinoma. Additional tests, including EMA, GFAP, NeuN, S-100, TTF1, CDX2, and a pancreatic battery consisting of insulin, gastrin, somatostatin, glucagon, VIP, and PP, all yielded negative results. This helped to eliminate the possibility of several other primary brain neoplasms and extracranial neuroendocrine neoplasms [3]. Intracranial involvement by neuroendocrine carcinoma is commonly seen as hematogenous metastasis.

The average time between initial diagnosis and presentation of intracranial involvement is around 13 months. Brain metastases in individuals with NECs are less than 5%. Notably, only about 1.4% of metastatic brain tumors are classified as NECs, with the majority originating from the lung. Gender doesn't significantly influence the incidence of brain metastases. Patients with metastatic neuroendocrine neoplasms in the brain often have additional local and distant metastases [1]. Further investigation is required about the appropriate management of primary brain neuroendocrine neoplasms. Based on existing evidence, it seems that radiation therapy and surgery may provide benefits in the treatment of brain neuroendocrine carcinomas. Moreover, it is recommended to use platinum-based chemotherapy as a treatment option for high-grade neuroendocrine carcinomas. In this instance, the patient under consideration had radiation treatment, followed by a combination of cisplatin and etoposide, resulting in beneficial outcomes. Therefore, this technique may be regarded as a potential therapy option for primary neuroendocrine carcinomas of the brain [10]. The prognosis of individuals with brain neuroendocrine neoplasms might significantly vary from that of metastatic brain neuroendocrine carcinomass due to the primary cause of death being attributed to systemic disease progression. Primary brain neuroendocrine carcinoma has a greater resemblance to non-metastatic neuroendocrine carcinoma, whereby the 10-year overall survival rate is at 47% [3].

Conclusion     

Primary brain neuroendocrine are infrequent pathological abnormalities. The first therapeutic approach for this particular kind of tumor involves surgical intervention, which is afterward complemented by radiation therapy and chemotherapy. The prognosis of malignant malignancies is associated with their histological grade. The instance that was described was a high-grade malignancy with a restricted outlook.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

All the authors have read and agreed to the final manuscript.

Figures     

Figure 1: brain magnetic resonance imaging (MRI) cuts axial t1 shows a frontal process with a double hypointense carnal and liquid hypo signal component

Figure 2: cerebral magnetic resonance imaging (MRI) cuts axial t2 flair that shows a frontal tumor process with the double component hypointense and high signal liquid cranium

Figure 3: histological image of a neuroendocrine brain tumor

Figure 4: CT scan of brain neuroendocrine carcinoma that showed a decrease in the size of the cerebral tumor process: A) transversal section; B) sagittal section

References