Mixed olfactory neuroblastoma and neuroendocrine carcinoma: An unusual case report and literature review

Update on olfactory neuroblastoma

Olfactory neuroblastomas are uncommon malignancies that arise from olfactory receptor cells located high in the nasal cavity. Accurate diagnosis plays a crucial role in determining clinical results and guiding treatment decisions. Diagnosis can be a major challenge for pathologists, especially when dealing with tumours with poor differentiation. The discovery of several molecular and immunohistochemical markers would help to overcome classification difficulties. Due to the paucity of large-scale studies, standardisation of diagnosis, treatment and prediction of outcome remains a challenge. Surgical resection by endoscopic techniques with the addition of postoperative irradiation is the treatment of choice. In addition, it is advisable to consider elective neck irradiation to minimise the risk of nodal recurrence. Molecular characterisation will help not only to make more accurate diagnoses but also to identify specific molecular targets that can be used to develop personalised treatment options tailored to each patient. The present review aims to summarise the current state of knowledge on histopathological diagnosis, the molecular biology and management of this disease.

Characterization of a Preclinical In Vitro Model Derived from a SMARCA4-Mutated Sinonasal Teratocarcinosarcoma

Sinonasal teratocarcinosarcoma (TCS) is a rare tumor that displays a variable histology with admixtures of epithelial, mesenchymal, neuroendocrine and germ cell elements. Facing a very poor prognosis, patients with TCS are in need of new options for treatment. Recently identified recurrent mutations in SMARCA4 may serve as target for modern therapies with EZH1/2 and CDK4/6 inhibitors. Here, we present the first in vitro cell line TCS627, established from a previously untreated primary TCS originating in the ethmoid sinus with invasion into the brain. The cultured cells expressed immunohistochemical markers, indicating differentiation of epithelial, neuroepithelial, sarcomatous and teratomatous components. Whole-exome sequencing revealed 99 somatic mutations including SMARCA4, ARID2, TET2, CDKN2A, WNT7A, NOTCH3 and STAG2, all present both in the primary tumor and in the cell line. Focusing on mutated SMARCA4 as the therapeutic target, growth inhibition assays showed a strong response to the CDK4/6 inhibitor palbociclib, but much less to the EZH1/2 inhibitor valemetostat. In conclusion, cell line TCS627 carries both histologic and genetic features characteristic of TCS and is a valuable model for both basic research and preclinical testing of new therapeutic options for treatment of TCS patients.

Childhood Malignancies-Clinico-demographic Profile of Patients Attending the Department of Otorhinolaryngology at a Tertiary Care Centre in North-East India

INTRODUCTION

Malignancies in children are different from those found in adults and are a significant cause of childhood mortality.They have varied clinical presentation depending on site and type of disease.It is essential to recognize the early signs and symptoms of malignancies in childhood, especially those involving head and neck region, so as to reduce childhood mortality and morbidity.

MATERIALS

A total of 2384 children were admitted over a period of 7 years. Out of these, 1004 fulfilled the inclusion criteria and were chosen for further evaluation.They were thoroughly evaluated by undertaking a detailed history and clinical examination.Whenever required, additional investigations were performed.After carrying out the necessary investigations, the cases were accordingly managed. Data was evaluated using proper statistical tools.

RESULTS

Out of 1004 cases fulfilling the inclusion criteria, 42 turned out to be malignant, with a male-to-female ratio of 1:1.2. Malignancies in children were more common in the age group of 11-18 years, followed by 1-5 years,6-10 years and 0-1 years,with rates of 59.5%, 21.4%, 16.7% and 2.4% respectively. A wide variety of tumour types were recorded,e.g.,Hodgkin's lymphoma,non-Hodgkin's lymphoma,acute leukemia,papillary carcinoma thyroid, nasopharyngeal carcinoma,Langerhans cell histiocytosis,rhabdomyosarcoma, olfactory neuroblastoma and salivary gland neoplasm.

CONCLUSION

Incidence of head and neck tumors in pediatric age group was found to be 1.76% with lymphoma being the most frequent.Commonest age of presentation was above 10 years. There was an overall female predominance with a male:female ratio of 1:1.2. Awareness of a potential malignancy and careful follow-up of children with suspicious head and neck cancers is mandatory for early diagnosis and prompt treatment.

Comparing the role of different treatment modalities in locoregionally advanced olfactory neuroblastoma: The 20-year clinical experience of a single institution

BACKGROUND

The clinical value of different treatment modalities, especially systemic chemotherapy (CT) in patients with locoregionally advanced olfactory neuroblastoma (LA ONB) remains unclear.

METHODS

Patients with LA ONB from 2000 to 2020 at our center were collected retrospectively. The entire cohort was divided into combined systemic and local therapy (CSLT) versus local therapy (LT) groups (grouping method 1), and the same cohort was divided into neoadjuvant chemotherapy (NAC) versus non-NAC groups (grouping method 2). CSLT group included patients treated with CT + LT. LT group included patients treated with surgery (SG), radiotherapy (RT), concurrent chemoradiotherapy (CCRT), or any combination of the above methods. LT group was further divided into mono-modality local therapy (MOLT) group and multi-modality local therapy (MULT) group. MOLT group included patients treated with RT alone or SG alone. MULT group included patients treated with SG + RT/CCRT, or CCRT alone. NAC group included patients treated with NAC + LT ± adjuvant chemotherapy (ADC). Non-NAC group included patients who received LT ± ADC.

RESULTS

A total of 111 patients with LA ONB were included. The median follow-up was 80.2 months (range, 2.1-254.9). The 5- and 10-year OS rates were 70.2% and 61.3%, respectively. In univariate analysis, patients treated with NAC (n = 43) had significantly better overall survival (OS) compared with those without NAC (n = 68) (p = 0.041). Patients in MULT group (n = 45) had significantly improved OS (p = 0.004) and PFS (p = 0.003) compared with those in MOLT group (n = 15). Multivariate analysis identified NAC and CSLT (n = 51) were independent prognostic factors for superior OS (p = 0.020, p = 0.046).

CONCLUSIONS

Our study suggested that CSLT, especially a combination of NAC and LT, improved the survival of patients with LA ONB. Multiple treatment modalities yielded better PFS and OS compared to single-modality treatment.

Olfactory Neuroblastoma: Morphological Reappraisal and Molecular Insights with Quantum Leap in Clinical Perspectives

PURPOSE OF REVIEW

The purpose of review is to provide a comprehensive review of the literature focusing on the recent advances in the diagnosis, molecular underpinning, and targeted therapy of olfactory neuroblastoma (ONB).

RECENT FINDINGS

Studies focused on the molecular fingerprinting of ONB are critical to engage new promising treatment strategies. Molecular-based subtype classifications have been proposed (basal-like ONB and neural-like ONB) but are not widely used. The rationale for implementation of DNA methylation analysis and IDH2 sequencing in routine work-up for ONB is gaining recognition. Expression of somatostatin receptors (SSTR) in ONB open new avenues for both, diagnostic (especially metastatic disease) and new treatment protocols with somatostatin analogs. Olfactory carcinoma is proposed as a unifying diagnostic terminology pertinent to epithelial divergent differentiation in olfactory neuroblastoma. Molecular (genetic and epigenetic) efforts on olfactory neuroblastoma are promising; however further refinement is needed for employment of these biomarkers as clinical standard of care. Ongoing and future multi-institutional collaborative studies will contribute to further understanding of ONB biology and aid the development of targeted treatments for this disease.

Sinonasal Tumors With Neuroepithelial Differentiation (Olfactory Carcinoma): Delineation of Their Pathologic and Clinical Features With Insights into Their Relationship to Olfactory Neuroblastoma and Sinonasal Carcinoma

Olfactory carcinoma is one of many names applied to sinonasal malignancies with histologic similarity to olfactory neuroblastoma (ONB) but cytokeratin expression or gland formation. It is unclear whether these neuroepithelial tumors represent a unified category and if they are separate from ONB and currently-recognized sinonasal carcinomas. This study aims to explore their clinicopathologic characteristics based on a large collective experience. A total of 53 sinonasal tumors with neuroepithelial differentiation were identified affecting 41 men and 12 women, median age 47 years (range: 12 to 82 y). The vast majority arose in the superior nasal cavity and presented at the high Kadish-Morita stage. Frequent histologic findings included (1) lobulated and solid growth, (2) rosettes and/or neurofibrillary stroma, (3) high-grade cytology, (4) complex, often ciliated glands, (5) nonfocal pancytokeratin expression, (6) neuroendocrine pos+itivity, and (7) variable S100-positive sustentacular cells. Twelve patients with available follow-up (48%) developed progressive disease at a median 8 months (range: 0 to 114 mo to progression), and 7 (28%) died of disease. Despite disparate historical terminology, neuroepithelial differentiation is a recurrent and recognizable histologic pattern that is associated with aggressive behavior in sinonasal tumors. While tumors with this phenotype may originate from olfactory mucosa, well-developed epithelial features warrant separation from conventional ONB and neural elements distinguish them from most sinonasal carcinomas. Although their full histogenesis remains uncertain and some heterogeneity may exist, we propose that this pattern is sufficiently distinctive to merit separate recognition as olfactory carcinoma. Use of consistent nomenclature may facilitate greater recognition of tumors with this phenotype and understanding of their pathogenesis and classification.