Neuroendocrine Carcinomas of the Larynx and Head and Neck: Challenges in Classification and Grading

Basic science and translational implications of current knowledge on neuroendocrine tumors

Neuroendocrine tumors (NETs) are a diverse group of malignancies that can occur in various organs, with a notable prevalence in the lungs and gastrointestinal tract, which are the focus of this Review. Although NETs are rare in individual organs, their incidence has increased over recent decades, highlighting the urgent need for current classification systems to evolve by incorporating recent advances in the understanding of NET biology. Several omics studies have revealed molecular subtypes, which, when integrated into existing classification frameworks, may provide more clinically relevant insights for patients with NETs. This Review examines recent progress in elucidating the biology of NETs, with a particular emphasis on the tumor microenvironment and cells of origin. The existence of different cells of origin, which may contribute to distinct molecular groups, along with profiles of immune infiltration - despite being generally low - could explain the emergence of more aggressive cases and the potential for metastatic progression. Given the molecular heterogeneity of NETs and the diversity of their microenvironments and different cells of origin, there is an urgent need to develop morphomolecular classification systems. Such systems would make it possible to better characterize tumor progression, identify new therapeutic targets, and, ultimately, guide the development of personalized therapies.

The Expression of Neuroendocrine Markers in a Small Subset of Ameloblastoma with Implications of Clusterin

Immunohistochemically, ameloblastomas often express CD56; however, novel neuroendocrine markers such as synaptophysin (SYP), insulinoma-associated protein 1 (INSM1), and chromogranin A (CgA) remain unexplored. We analyzed 36 ameloblastoma specimens for CD56, SYP, CgA, and clusterin (CLU) and examined limited samples for INSM1 expression by performing immunohistochemistry, transmission electron microscopy, and reverse transcriptase-polymerase chain reaction. Our findings indicate that the limited cells were positive for CD56, SYP, CgA, INSM1, and CLU expression in 72% (26/36), 14% (5/36), 0% (0/40), 80% (4/5), and 22% (8/36) of the cases, respectively. CD56 expression correlated with older age, but not with subtype, SYP, and CLU expression. However, SYP-positive cases were exclusively found in CD56- and CLU-positive cases, and SYP and CLU expression were significantly correlated. Selected cases had dense-core granules and NCAM1 and SYP mRNA expression. This study is the first to suggest neuroendocrine differentiation in ameloblastomas, as indicated by SYP and INSM1 immunoexpression and the presence of dense-core granules, which are consistent with the recent World Health Organization classification of Head and Neck Tumors guidelines. SYP-positive and CgA-negative phenotypes may characterize neuroendocrine differentiation in ameloblastoma. Although the underlying molecular mechanism remains unclear, CLU expression may be associated with neuroendocrine differentiation.

Large cell neuroendocrine carcinoma originating in the subglottic larynx

Large cell neuroendocrine carcinoma (LCNEC) of the larynx is an exceedingly rare cancer of the head and neck that is difficult to diagnose. Few case reports of laryngeal LCNEC exist within the literature, and it was not until recently that LCNEC was recognized as a discrete subtype of neuroendocrine carcinoma. Given its recent recognition as a distinct subtype, histologic characteristics distinguishing LCNEC from other poorly differentiated carcinomas remain under investigation. Various reports have shown genetic alterations such as p53 and/or p16 overexpression, which are typically associated with infection by human papilloma virus (HPV). However, some reports have shown p53 and/or p16 overexpression in HPV negative samples. In this case, we discuss a 67-year-old patient with a history of extensive alcohol and tobacco use with a newly diagnosed T4N0M0, high grade, LCNEC of the subglottic larynx. Tumor pathology demonstrated positive staining for typical neuroendocrine (NE) markers like synaptophysin and chromogranin A; however, there was diffuse CK34βE12 and p16 expression. LCNEC is a newly classified subtype of poorly differentiated neuroendocrine (NE) tumors, and the diagnosis requires consideration of the clinical presentation, microscopic features, and immunostaining markers.

Clinical diagnosis and treatment of G2 laryngeal neuroendocrine tumors

BACKGROUND

Neuroendocrine tumors are rare malignancies of the head and neck, especially in the larynx. Variations in the location and morphology of laryngeal neuroendocrine tumors result in a lack of standardized clinical treatment.

OBJECTIVE

This study aimed to examine the treatment and prognosis of laryngeal neuroendocrine tumors in the G2 stage.

MATERIAL AND METHODS

Data from eight patients diagnosed with G2 stage laryngeal neuroendocrine tumors, this collection of common clinical cases was analyzed retrospectively to examine the disease's clinical characteristics, treatment, and prognosis affecting the larynx.

RESULTS

Seven cases were supraglottic type and one was a glottic type. These cases were treated with open surgery and CO2 laser resection with support laryngoscopy, respectively. After surgery, six patients survived, one passed away due to pulmonary metastasis, and one case was lost to follow-up. OS and DSF rates at 1, 3, 5 years were 87.50%, 65.63% and 65.60%, respectively.

CONCLUSION AND SIGNIFICANCE

The clinical manifestations of G2 stage laryngeal neuroendocrine tumors varied across different locations. Surgical resection of the lesion is the standard treatment. Selection between open neck surgery and support laryngoscope CO2 laser surgery depends on the tumor's size and location. Following radical surgery, the tumor demonstrates a favorable prognosis.

High-grade neuroendocrine head and neck cancer: Case series and review of the literature

BACKGROUND

High-grade neuroendocrine cancers (NEC) of the head and neck (HN) are rare and aggressive, accounting for ≤1 % of all HN cancers, with a 5-year overall survival (OS) of ≤20 %. This case series examines clinical characteristics, treatments, and outcomes of patients diagnosed at a regional UK HN cancer centre over the last 23 years.

METHODS

A retrospective review of medical records was conducted for all patients diagnosed with NEC HN from 1st January 2000 until 1st March 2023 at Velindre Cancer Centre.

RESULTS

During the study period, 19 cases of NEC HN were identified, primarily affecting males (n = 15, 79 %). Median age of 67 years (range: 44-86). At diagnosis, 32 % of patients (n = 6) were smokers. The most common primary tumour sites were larynx (n = 5, 26.3 %) and sinonasal (n = 5, 26.3 %). Most patients presented with advanced loco-regional disease or distant metastasis, with stage IVA (n = 6, 32 %) and stage IVC (n = 6, 32 %) being the most common. The key pathology marker was synaptophysin, present in 100 % of the tested patients (n = 15). In the study, of the 12 patients with non-metastatic disease, 10 received a combination of treatments that included radiotherapy (RT). Some of these patients also received chemotherapy (CT) at the same time as their radiotherapy. Surgery alone was used in two patients with stage II disease. Seven subjects had complete responses, and one achieved a partial response. Among the seven metastatic patients, three received CT, and one underwent palliative RT, all achieving a partial response. In all cases, the CT used was carboplatin and etoposide. After a median follow-up of 11 months (range: 1-96), the median OS was 27 months for the overall population, 51 months for those treated radically, and three months for metastatic patients with palliative treatment. The 1-year OS for all patients was 54.3 %, the 2-year OS was 46.5 %, and the 5-year OS was 23.3 %. Among patients treated radically, these rates were 65.3 %, 52.2 %, and 26.1 %, respectively. For patients treated palliatively, the 1-year OS was 33.3 %.

CONCLUSION

This case series contributes preliminary observations on the characteristics and management of non-metastatic NEC HN, suggesting potential benefits from multimodality treatment strategies. Given the small cohort size, these observations should be interpreted cautiously and seen as a foundation for further research.

Oropharyngeal Mixed Neuroendocrine-Nonneuroendocrine Neoplasm (MiNEN): A Case Report and Literature Review

Mixed neuroendocrine-nonneuroendocrine (MiNEN) neoplasms in the head and neck are exceptionally rare biphasic tumors with unclear pathogenesis and an aggressive clinical behavior. This is the first reported case of an oropharyngeal MiNEN with the nonneuroendocrine component being an HPV-associated adenocarcinoma. The tumor arose in a 56 year-old male with history of long-term cigarette smoking and was composed of an adenocarcinoma intermixed with a small cell neuroendocrine carcinoma. P16 immunohistochemical stain and HPV16/18 in-situ hybridization were strongly and diffusely expressed in both components.

Long-term outcomes and prognosis of neuroendocrine neoplasms of the head and neck: a cohort from a single institution

BACKGROUND

Neuroendocrine neoplasm is a rare cancer of head and neck. This study aimed to evaluate clinical features, treatment outcomes, and prognostic factors of neuroendocrine neoplasm of head and neck treated at a single institution.

METHODS

Between Nov 2000 and Nov 2021, ninety-three patients diagnosed with neuroendocrine neoplasms of head and neck treated at our institution were reviewed retrospectively. The initial treatments included chemotherapy (induction, adjuvant, or concurrent) combined with radiotherapy in 40 patients (C + RT group), surgery followed by post-operative RT in 34 (S + RT group), and surgery plus salvage therapy in 19 patients (S + Sa group).

RESULTS

The median follow-up time was 64.5 months. 5-year overall survival rate (OS), progression-free survival rate (PFS), loco-regional relapse-free survival free rate (LRRFS) and distant metastasis-free survival rate (DMFS) were 64.5%, 51.6%, 66.6%, and 62.1%, respectively. For stage I-II, the 5-year LRRFS for patients' treatment regimen with or without radiotherapy (C + RT and S + RT groups versus S + Sa group) was 75.0% versus 12.7% (p = 0.015) while for stage III-IV, the 5-year LRRFS was 77.8% versus 50.0% (p = 0.006). The 5-year DMFS values for patients with or without systemic therapy (C + RT group versus S + RT or S + Sa) were 71.2% and 51.5% (p = 0.075). 44 patients (47.3%) experienced treatment failure and distant metastasis was the main failure pattern.

CONCLUSIONS

Radiotherapy improved local-regional control and played an important role in the management of HNNENs. The optimal treatment regimen for HNNENs remains the combination of local and systemic treatments.

Giant laryngeal neuroendocrine neoplasm causing airway obstruction: A case report and literature review

RATIONALE

Laryngeal neuroendocrine neoplasm (NEN) is a rare and heterogeneous disease that originates from neuroendocrine cells. It mainly occurs in middle-aged and elderly men. Due to the lack of specific clinical and imaging manifestations, diagnosis and treatment of the disease pose a challenge. Therefore, a consensus on the diagnosis and treatment of the disease is necessary. By discussing this case, we will be able to gain further insight into laryngeal NEN and will be able to provide some recommendations for the future management of this rare disease.

PATIENT CONCERNS

A 67-year-old man was admitted to our department with a history of sore throat and dyspnea. After admission, the patient experienced acute airway obstruction and experienced an emergency bedside tracheotomy.

DIAGNOSES

Flexible fiberoptic laryngoscopy and enhanced CT showed a cauliflower-like mass in the left supraglottic region and obstructed most of the laryngeal cavity. We biopsied the mass, and the pathology showed a poorly differentiated adenocarcinoma.

INTERVENTIONS

A horizontal hemilaryngectomy and left neck dissection were performed. At 4 weeks after the operation, the patient underwent chemotherapy and radical radiotherapy.

OUTCOMES

After a 1-year postoperative follow-up, the patient recovered well and showed no signs of recurrence.

LESSONS

Laryngeal neuroendocrine neoplasm is very rare, early diagnosis remains difficult. Radical surgery combined with postoperative chemoradiotherapy is currently the most appropriate treatment.

Poorly differentiated neuroendocrine carcinoma originating in the subglottic larynx: A case report with imm unohistochemical study

Key Clinical Message

Laryngeal neuroendocrine carcinomas are the most common non-squamous neoplasm of the larynx. Due to the rarity of the tumor, pathological diagnosis should be confirmed by immunohistochemistry.

Abstract

Laryngeal neuroendocrine carcinomas (LNECs) are a rare cancer of the head and neck. Few case reports of poorly differentiated neuroendocrine carcinoma originating in the subglottic larynx exist within the literature. In this case, we discuss a 57-year-old patient with a history of four-month hoarseness with a newly diagnosed of poorly differentiated neuroendocrine carcinoma in the subglottic larynx. Treatment and prognosis of the various NEC groups differ, so precise identification requires consideration of the microscopic findings and immunostaining analysis. immunohistochemistry staining demonstrated positive result for cytokeratin 7, synaptophysin, chromogranin, CD 56, with the Ki-67 index of45%. Although surgery is usually the treatment for all tumor types, chemo radiotherapy is recommended for poorly differentiated NECs because surgery is ineffective.

Small Cell Non-keratinizing Neuroendocrine Carcinoma Involving the Larynx and the Base of the Tongue: A Rare Case With a Locally Aggressive Spread

Squamous cell carcinoma is the most predominant type of malignancy in the head and neck region with neuroendocrine carcinomas (NECs) being a rare occurrence. Here we report a rare case of small cell non-keratinizing NEC (WHO grade 3), TNM (tumor, node, and metastasis) stage T3N1M0, involving the larynx and the base of the tongue, in a 54-year-old male patient, demonstrating its rarity in an uncommon anatomical site and an aggressive and relatively uncommon pattern of spread for this tumor, over a period of two months. NECs in the head and neck region, especially those affecting the larynx and the posterior third of the tongue, remain exceedingly rare, comprising only a small fraction of malignancies in this region. The aggressive nature and distinct pattern of spread observed in this case underscore the importance of recognizing such unusual presentations for appropriate diagnosis and management. Given the rarity of this tumor type, a comprehensive understanding of its clinicopathological features is essential for guiding effective treatment strategies. We also discuss the treatment.

Primary Surgical Management of Laryngeal Neuroendocrine Neoplasms: A Single Institution Case Series

Objective: Laryngeal neuroendocrine neoplasms (NENs) are rare diseases. A single institution retrospective study was done of the outcome of patients with laryngeal NENs who undergo primary surgery as the first treatment modality. Methods: Retrospective analysis of medical records of patients with laryngeal NENs between 2009 and 2018. Cases were classified by applying the 2022 World Health organization Classification of Head and Neck Tumors (5th edition). Results: Six patients were eligible at our tertiary center: 1 large cell neuroendocrine carcinoma (NEC), 3 small cell NEC, 1 neuroendocrine tumor grade 1, and 1 neuroendocrine tumor grade 2. All admitted patients received upfront surgeries, including 3 transoral CO2 laser surgeries and 3 total laryngectomies with or without elective neck dissection. Four patients underwent subsequent chemoradiotherapy. Although 3 patients had recurrent disease and distal metastasis, the overall survival was generally improved. Conclusion: According to our institutional experience, upfront surgery in the first-line setting of a multi-modality approach with adjuvant chemoradiotherapy plays a very important role in managing laryngeal NECs, and may confer additional survival benefit in some patients of the large cell carcinoma subgroup.

Non-squamous Laryngeal Cancer

The pathology of non-squamous carcinoma of the larynx is broad and there is a wide differential diagnosis. The most common presenting symptoms for laryngeal malignancies, both squamous and non-squamous, are hoarseness and dyspnea. Presentation with persistent or worsening symptoms and a submucosal lesion should raise suspicion for a non-squamous malignancy of the larynx. Accurate histology determines the most appropriate treatment and has an impact on prognosis.

Top 10 Nested Pattern Head and Neck Lesions to Notice

BACKGROUND

Nested is defined as "cellular clusters arranged in small groupings with intervening vascular or stromal networks, lacking lumens or glandular formation." Using this definition, multiple neoplastic and non-neoplastic lesions of the head and neck come into the differential. We have broadly organized the differential diagnosis of "nested" tumors into entities with neuroendocrine differentiation, squamous differentiation, thyroid follicular cell differentiation, and other lesions.

METHODS

Review.

RESULTS

Many different entities have a nested appearance and the morphologic, immunohistochemical, clinical, and radiographic features contribute to the differential diagnosis. The different tumors covered in this review include neuroendocrine neoplasms, paraganglioma, middle ear neuroendocrine tumor (formerly known as middle ear adenoma), medullary thyroid carcinoma, poorly differentiated thyroid carcinoma, olfactory neuroblastoma, ectopic pituitary neuroendocrine tumor, hyalinizing trabecular tumor, solid subtype of papillary thyroid carcinoma, solid cell nests/C-cell hyperplasia, necrotizing sialometaplasia, and meningioma.

CONCLUSION

In this review, we discuss the morphologic and immunohistochemical features of the covered entities as a guide to differential diagnosis when nested-patterned head and neck lesions are encountered.

Clinical Diagnosis and Treatment of Primary Laryngeal Neuroendocrine Carcinoma

OBJECTIVE

This study aims to investigate the clinical diagnosis and treatment characteristics of primary laryngeal neuroendocrine carcinoma.

PATIENTS AND METHODS

A retrospective analysis was performed for the data of 6 patients with primary laryngeal neuroendocrine carcinoma admitted to the Department of Otorhinolaryngology of Dalian Central Hospital from September 2015 to January 2022, all of whom were male patients. And laryngoscopy showed that 4 had a similar appearance to hemangioma, 1 had nodular hyperplasia, and 1 was papilloma-like. The site of onset was located on the laryngeal surface of the epiglottis in 3 cases, situated in the aryepiglottic fold in 2 cases, and the posterior ventricular zone in 1 case. Five patients underwent surgery, including 4 by transoral endoscopic cryogenic plasma radiofrequency mass resection; one underwent a cervical lymph node dissection and supraglottic horizontal hemilaryngectomy. The remaining 1 case was treated in another hospital after the pathological diagnosis was confirmed by biopsy. All patients had no cervical lymph node metastases and were not supplemented with chemoradiotherapy.

RESULTS

The postoperative pathological diagnosis of all 5 patients was neuroendocrine carcinoma. No cancer cells were seen at the margins and base. One patient was lost to follow-up after treatment in another hospitals and the rest were followed up for 6 months to 6 years. One patient had removed laryngeal tumor and epiglottis by a low-temperature plasma radiofrequency ablation, recurrence 1 year after surgery, and no recurrence for 5 years after supraglottic horizontal hemilaryngectomy combined with prophylactic cervical lymph node dissection, no recurrence for the other 4 patients after 6 months to 4 years of follow-up.

CONCLUSION

The common sites of laryngeal neuroendocrine carcinoma are the laryngeal surface of the epiglottis and the aryepiglottic fold. The appearance of the tumor is mainly similar to that of hemangioma. Moreover, a common pathological classification is atypical carcinoid tumors, where early detection and surgical treatment can achieve a good therapeutic effect.

Current Insights and Progress in the Clinical Management of Head and Neck Cancer

Head and neck cancer (HNC), also known as the cancer that can affect the structures between the dura mater and the pleura, is the 6th most common type of cancer. This heterogeneous group of malignancies is usually treated with a combination of surgery and radio- and chemotherapy, depending on if the disease is localized or at an advanced stage. However, most HNC patients are diagnosed at an advanced stage, resulting in the death of half of these patients. Thus, the prognosis of advanced or recurrent/metastatic HNC, especially HNC squamous cell carcinoma (HNSCC), is notably poorer than the prognosis of patients diagnosed with localized HNC. This review explores the epidemiology and etiologic factors of HNC, the histopathology of this heterogeneous cancer, and the diagnosis methods and treatment approaches currently available. Moreover, special interest is given to the novel therapies used to treat HNC subtypes with worse prognosis, exploring immunotherapies and targeted/multi-targeted drugs undergoing clinical trials, as well as light-based therapies (i.e., photodynamic and photothermal therapies).

ATYPICAL CARCINOID OF THE LARYNX AND MULTIFOCAL METASTASES

Neuroendocrine carcinoma (NEC) of the larynx is the most frequent neuroendocrine neoplasm of the head and neck and the most common nonsquamous carcinoma of the larynx. It usually occurs in the supraglottic area, in smoking men. We report a case of a 58-year-old woman with no history of smoking who presented with an atypical carcinoid, arising in the right piriform sinus of the larynx. During the 5-year follow-up, the patient developed metastases in the lymph nodes, palatine tonsils, parotid glands, breasts and skin. For this reason the patient underwent several surgical procedures, radiotherapy and eventually was qualified for chemotherapy. Our case shows that NEC of the larynx can have an atypical presentation. The diagnosis requires careful pathological evaluation with immunohistochemistry and a wide spectrum of imaging. The serum concentration of chromogranin A seems to be not useful in the diagnosis and follow-up of laryngeal NEC.

Sore Throat: Can It Be Primary Laryngeal Small Cell Carcinoma?

Small cell carcinoma of the larynx is a rare form of neuroendocrine carcinoma. Clinical and radiological properties are similar to other laryngeal cancers, prompting histopathology examination. Symptoms include sore throat, dysphagia, odynophagia, and weight loss. Multiple management options have been demonstrated in the literature. However, combined radiation and chemotherapy have proven to improve survival. Unfortunately, the prognosis for this cancer is dismal, as survival from diagnosis rarely exceeds two years. In this article, we present a 64-year-old female patient who presented with a sore throat and was diagnosed with primary small cell cancer of the larynx. Despite the relapse after the initial four cycles of chemotherapy with carboplatin and etoposide, our patient responded well to nivolumab and ipilimumab and is still in remission on a six-month follow-up.

Combined large cell neuroendocrine carcinoma and squamous cell carcinoma of the oropharynx: A collision course of tumors

Combined large cell neuroendocrine carcinoma (LCNEC) and squamous cell carcinoma (SCC) of the H&N are exceptionally rare. We present the case of combined p16 negative SCC and LCNEC of the oropharynx treated with combination chemotherapy. This is the third reported case of combined neuroendocrine carcinoma and SCC of the oropharynx.

Oral and Maxillofacial Neuroendocrine Carcinoma: A Systematic Review

The aim of the present study was to integrate the available data published in the literature on oral and maxillofacial neuroendocrine carcinomas concerning the demographic, clinical and histopathological features of this condition. An electronic search with no publication date restriction was undertaken in April 2021 in four databases. Eligibility criteria included reports published in English having enough data to confirm a definite diagnosis, always showing a neuroendocrine marker. Cases originating in the oropharynx, including base of the tongue and tonsils, were excluded. Outcomes were evaluated by the Kaplan-Meier method along with Cox regression. Twenty-five articles (29 cases) from nine different countries were detected. Mean patient age was 56.3 (± 17.5) years, with a slight male predilection. Symptomatology was present in 72.2% of informed cases. Regarding clinical presentation, a non-ulcerated nodule located in the gingiva with a mean size of 3.4 (± 2.0) cm was most frequently reported. Concomitant metastasis was identified in seven individuals. Histopathologically, most neoplasms were of the small cell type, and immunohistochemistry for both epithelial and neuroendocrine differentiation was used in 65.5% cases. Radical surgery was the treatment of choice in almost all cases, with or without adjuvant therapy. Mean follow-up was 20.5 (± 21.2) months, and only four patients developed recurrences. Eleven (44.0%) individuals died due to the disease. Ulcerated lesions were a prognostic factor. This study provides knowledge that can assist surgeons, oncologists, and oral and maxillofacial pathologists with the diagnosis and management of neuroendocrine carcinomas. Our findings demonstrated that the long-term prognosis of this lesion continues to be poor.

Surgical palliation in poorly differentiated neuroendocrine carcinoma of the hypopharynx: Case report

Background

Primary neuroendocrine carcinomas (NECs) are very rare entities accounting for 0.49% of all malignancies. Within the head and neck, the most common sites are the larynx and paranasal sinuses, while the hypopharynx is seldom described.

Case

We present a patient with a poorly differentiated metastatic NEC of the hypopharynx treated palliatively with organ‐preserving surgery and post‐operative chemotherapy, and literature review for well‐documented pure hypopharyngeal NECs. Our patient died of chest infection during chemotherapy, 4 months after surgery.

Conclusion

Chemotherapy remains the mainstay of treatment in the presence of metastases with 2‐year overall survival of 15.7%. Due to the aggressive nature of poorly differentiated metastatic NECs, surgical management is seldom considered. We report and advocate the successful palliative role of organ‐preserving, minimally invasive trans‐oral LASER micro‐surgery and neck dissection to control loco‐regional head and neck disease, safe‐guarding better quality of home life, despite limited life expectancy for this condition.

Neuroendocrine Carcinoma of the Larynx and Pharynx: A Clinical and Histopathological Study

Simple Summary

Neuroendocrine carcinomas (NECs) of the head and neck are rare. The presented series of 20 patients with laryngeal and pharyngeal NECs is population-based and one of the largest published to date. We analyzed the treatment results according to the type of therapy and the role of various standard (synaptophysin-chromogranin-CD56, Ki-67, p16, HPV, and EBV) and some novel (INSM1 and PD-L1) neuroendocrine markers or potential prognosticators. The results indicate the following: (1) laryngeal and pharyngeal NECs accounted for 0.43% and 0.17% of the cases in the corresponding tumor groups, respectively; (2) neuroendocrine differentiation can be reliably determined by INSM1 immunohistochemistry; (3) the prognosis was determined by the nodal stage and TNM stage but not by the histological grade (which refers to moderately and poorly differentiated NECs); (4) except in well-differentiated NECs and early-stage (T1-2N0-1) moderately/poorly differentiated NECs, aggressive multimodal therapy is needed; and (5) the p16, HPV, and EBV statuses failed to show any prognostic value.

Abstract

Neuroendocrine carcinomas (NECs) of the head and neck are rare and the experience scanty. The Cancer Registry of Slovenia database was used to identify cases of laryngeal and pharyngeal NECs diagnosed between 1995–2020. Biopsies were analyzed for the expression of standard neuroendocrine markers (synaptophysin, chromogranin, CD56), INSM1, Ki-67, p16, and PD-L1 (using the combined positive score, CPS). In situ hybridization for human papillomavirus (HPV) and Epstein–Barr virus (EBV) was performed. Twenty patients (larynx, 12; pharynx, 8) were identified. One tumor was well differentiated (WD), five were moderately differentiated (MD), and 14 were poorly differentiated (PD). Disease control was achieved solely by surgery in 4/4 MD/PD T1-2N0-1 tumors. Eight patients died of the disease, seven of which were due to distant metastases. All three traditional markers were positive in 11/17 NECs and the INSM1 marker in all 20 tumors. Two of fourteen p16-positive tumors were HPV-positive, but all three nasopharyngeal NECs were EBV-negative. Three tumors had CPSs ≥ 1. In conclusion, INSM1 was confirmed to be a reliable marker of neuroendocrine differentiation. Except in WD and early-stage MD/PD tumors, aggressive multimodal therapy is needed; the optimal systemic therapy remains to be determined. p16, HPV, and EBV seem to bear no prognostic information.

Neuroendocrine Neoplasms of the Larynx: A Clinicopathologic Analysis of 27 Neuroendocrine Tumors and Neuroendocrine Carcinomas

Laryngeal neuroendocrine neoplasms (NENs) are rare and heterogeneous, encompassing well-differentiated neuroendocrine tumors (NETs; grade 1, 2, and 3), neuroendocrine carcinomas (NECs, small cell and large cell types), and mixed neuroendocrine non-neuroendocrine neoplasms (MiNEN). We aimed to study the clinicopathologic spectrum of these neoplasms. A retrospective review of all primary laryngeal NENs diagnosed from 2005 to 2017 was undertaken. Mitotic index was divided into < 2, ≥ 2-10, and > 10 mitoses/2 mm², with a Ki-67 labelling index of < 2%, ≥ 2-20%, and > 20% for the NET grade 1, 2 and 3 categories, respectively. A total of 27 patients were included. The median age at presentation was 60 years; the male-to-female ratio was 8:1. Supraglottis (n = 22) was the most frequently affected subsite. There were 9 NETs grade 2 (G2), and 18 NECs cases. There were no NET grade 1 or 3 cases in our cohort. Among the NETs G2, the morphology was epithelioid (2), plasmacytoid (3), clear (2), oncocytic (1), and rhabdoid (1). Unique 'glomeruloid structures' (n = 5), calcification (n = 3), lymphoid aggregates (n = 5), intranuclear inclusions (n = 2), hyaline globules (n = 3), and Leisegang rings (n = 2) were identified. NECs comprised 16 small cell neuroendocrine carcinoma and 2 large cell neuroendocrine carcinoma. On immunohistochemistry, tumor cells expressed AE1/AE3 (86%), synaptophysin (100%), chromogranin (100%), INSM1 (100%), calcitonin (33.3%). In the NEC group, p53 aberrant expression (87.5%), Retinoblastoma (Rb) loss (88.2%), and diffuse p16 immunoreactivity (66.7%) were additionally observed. Lymph-node metastasis was detected in 62.5% and 85.7%, while distant metastasis in 55.6% and 76.9%, respectively in NET G2 and NEC. Laryngeal NENs are aggressive neoplasms with a high rate of nodal and distant metastasis. Awareness of the wide pathologic spectrum of laryngeal NENs and appropriate use of IHC is needed to render an accurate diagnosis. Ki67 assessment is strongly recommended for laryngeal NEN prognostication.

Neuroendocrine carcinomas of the head and neck: A small case series

INTRODUCTION

Neuroendocrine tumors of the head and neck are rare and arise either from epithelial or neuronal origin. Debate continues over the classification systems and appropriate management of these pathologies.

OBJECTIVE

By investigating a small set of cases of high grade epithelial-derived neuroendocrine tumors of the head and neck (neuroendocrine carcinomas or NEC) from one institution, we compare survival rates of NEC of the head and neck to pulmonary NEC.

METHODS

We identified patients from pathology records with neuroendocrine carcinomas of the head and neck and retrospectively collected clinical data as well as immunohistochemical (IHC) staining data.

RESULTS

We identified 14 patients with NEC, arising from the parotid (n = 5), nasal cavity (n = 4), larynx (n = 2), and other regions (n = 2). One additional patient had NEC arising in two sites simultaneously (parotid and nasal). Staining patterns using IHC were relatively consistent across specimens, showing reactivity to chromogranin and synaptophysin in 73% and 100% of specimens, respectively. Treatment courses varied across patients and included combinations of surgery, chemotherapy, and/or radiation. The overall survival rate at 1, 2, and 5 years of these patients was 56%, 56%, and 43% with a mean follow-up time of 2.12 years.

CONCLUSION

Compared to NEC arising in the lung, this subset of patients had better survival rates, but worse survival rates than the more common squamous cell carcinoma of the head and neck.

Oropharyngeal Mixed Neuroendocrine-Nonneuroendocrine Neoplasm (MiNEN): A Case Report and Literature Review

Primary mixed neuroendocrine-nonneuroendocrine neoplasm (MiNEN) of the head and neck region is a rare biphasic tumor with an aggressive biological behavior. This report highlights an additional case of oropharyngeal MiNEN in a 46-year-old male patient with a previous long-term smoking history. Histologic evaluation revealed a biphasic tumor infiltrating the lamina propria. The first component consisted of a classic keratinizing squamous cell carcinoma. The second component consisted of small-to-intermediate sized cells with neuroendocrine features. Synaptophysin and CD56 immunohistochemical stains confirmed neuroendocrine lineage in this component. The presence of two morphological components with neuroendocrine and nonneuroendocrine features on histologic assessment should alert the pathologist to consider a MiNEN in their case work-up.

Nomograms Forecasting Long-Term Overall and Cancer Specific Survival of Patients With Head and Neck Neuroendocrine Carcinoma

Background

The purpose of this retrospective analysis was to build and validate nomograms to predict the cancer-specific survival (CSS) and overall survival (OS) of head and neck neuroendocrine carcinoma (HNNEC) patients.

Methods

A total of 493 HNNEC patients were selected from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015, and 74 HNNEC patients were collected from the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University/Hunan Cancer Hospital (HCH) between 2008 and 2020. Patients from SEER were randomly assigned into training (N=345) and internal validation (N=148) groups, and the independent data group (N=74) from HCH was used for external validation. Independent prognostic factors were collected using an input method in a Cox regression model, and they were then included in nomograms to predict 3-, 5-, and 10-year CSS and OS rates of HNNEC patients. Finally, we evaluated the internal and external validity of the nomograms using the consistency index, while assessing their prediction accuracy using calibration curves. A receiver operating curve (ROC) was also used to measure the performance of the survival models.

Results

The 3-, 5-, and 10-year nomograms of this analysis demonstrated that M classification had the largest influence on CSS and OS of HNNEC, followed by the AJCC stage, N stage, age at diagnosis, sex/gender, radiation therapy, and marital status. The training validation C-indexes for the CSS and OS models were 0.739 and 0.713, respectively. Those for the internal validation group were 0.726 and 0.703, respectively, and for the external validation group were 0.765 and 0.709, respectively. The area under the ROC curve (AUC) of 3-, 5-, and 10-year CSS and OS models were 0.81, 0.82, 0.82, and 0.78, 0.81, and 0.82, respectively. The C-indexes were all higher than 0.7, indicating the high accuracy ability of our model's survival prediction.

Conclusions

In this study, prognosis nomograms in HNNEC patients were constructed to predict CSS and OS for the first time. Clinicians can identify patients' survival risk better and help patients understand their survival prognosis for the next 3, 5, and 10 years more clearly by using these nomograms.

Coexistence of Basaloid Squamous Cell Carcinoma and Large Cell Neuroendocrine Carcinoma in the Larynx: A Case Report and Literature Review

Basaloid squamous cell carcinoma and large cell neuroendocrine carcinoma are not common in head and neck, these tumors rarely occur in the larynx but both have highly aggressive clinical behavior and a high mortality rate. The diagnosis is complicated by these tumors' atypical clinical and pathological features. This case details a coexistence of basaloid squamous cell carcinoma and large cell neuroendocrine carcinoma of a woman in the larynx. The patient underwent endoscopy- and coblation-assisted transoral microsurgery to achieve hyoid horizontal epiglottidectomy and has no recurrence after 12 months of follow-up.

Update on Neuroendocrine Carcinomas of the Larynx

OBJECTIVES

Laryngeal neuroendocrine carcinomas are heterogeneous neoplasms characterized by neuroendocrine differentiation. Their prognoses are dependent on tumor type, therefore different classifications have been developed. Moreover, other tumors have overlapping pathologic features posing a range of diagnostic possibilities.

METHODS

A review of the literature was performed to comprehensively understand the classification and diagnosis of these tumors.

RESULTS

We review the past and present classification systems, with emphasis to the latest 2017 World Health Organization Classification of Head and Neck Tumors. We highlight salient clinicopathologic features and discuss the presumptive etiologic role of human papilloma virus. We share a practical algorithmic approach to the diagnosis of suspected neuroendocrine neoplasms of the larynx including a novel marker for neuroendocrine differentiation, insulinoma-associated protein 1.

CONCLUSIONS

Accurate diagnosis and grading of laryngeal neuroendocrine carcinomas is critical for prognostication and therapeutic decision making. The use of an algorithm is instrumental in assuring the exclusion of mimickers.

Well-differentiated Neuroendocrine Carcinoma of the Larynx: Confusion of Terminology and Uncertainty of Early Studies

Well-differentiated neuroendocrine carcinoma (also known as "carcinoid") of the larynx is an exceedingly rare tumor that has an epithelial origin. These tumors are malignant and have a low, but definite, risk of metastasis. Although it can be challenging, this tumor should be differentiated from moderately differentiated neuroendocrine carcinoma (also known as "atypical carcinoid"). The clinical and pathologic features of this tumor, as well as treatment and prognosis, are reviewed in detail.