Moderately differentiated neuroendocrine carcinoma of the larynx. A clinicopathologic study of 54 cases

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Overview of the 2022 WHO Classification of Head and Neck Neuroendocrine Neoplasms

This review article provides a brief overview of the new WHO classification by adopting a question-answer model to highlight the spectrum of head and neck neuroendocrine neoplasms which includes epithelial neuroendocrine neoplasms (neuroendocrine tumors and neuroendocrine carcinomas) arising from upper aerodigestive tract and salivary glands, and special neuroendocrine neoplasms including middle ear neuroendocrine tumors (MeNET), ectopic or invasive pituitary neuroendocrine tumors (PitNET; formerly known as pituitary adenoma) and Merkel cell carcinoma as well as non-epithelial neuroendocrine neoplasms (paragangliomas). The new WHO classification follows the IARC/WHO nomenclature framework and restricts the diagnostic term of neuroendocrine carcinoma to poorly differentiated epithelial neuroendocrine neoplasms. In this classification, well-differentiated epithelial neuroendocrine neoplasms are termed as neuroendocrine tumors (NET), and are graded as G1 NET (no necrosis and < 2 mitoses per 2 mm²; Ki67 < 20%), G2 NET (necrosis or 2-10 mitoses per 2 mm², and Ki67 < 20%) and G3 NET (> 10 mitoses per 2 mm² or Ki67 > 20%, and absence of poorly differentiated cytomorphology). Neuroendocrine carcinomas (> 10 mitoses per 2 mm², Ki67 > 20%, and often associated with a Ki67 > 55%) are further subtyped based on cytomorphological characteristics as small cell and large cell neuroendocrine carcinomas. Unlike neuroendocrine carcinomas, head and neck NETs typically show no aberrant p53 expression or loss of RB reactivity. Ectopic or invasive PitNETs are subtyped using pituitary transcription factors (PIT1, TPIT, SF1, GATA3, ER-alpha), hormones and keratins (e.g., CAM5.2). The new classification emphasizes a strict correlation of morphology and immunohistochemical findings in the accurate diagnosis of neuroendocrine neoplasms. A particular emphasis on the role of biomarkers in the confirmation of the neuroendocrine nature of a neoplasm and in the distinction of various neuroendocrine neoplasms is provided by reviewing ancillary tools that are available to pathologists in the diagnostic workup of head and neck neuroendocrine neoplasms. Furthermore, the role of molecular immunohistochemistry in the diagnostic workup of head and neck paragangliomas is discussed. The unmet needs in the field of head and neck neuroendocrine neoplasms are also discussed in this article. The new WHO classification is an important step forward to ensure accurate diagnosis that will also form the basis of ongoing research in this field.

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 carcinoma of the larynx with Lambert-Eaton myasthenic syndrome: a rare case report and literature review

This current report describes a rare clinical case of neuroendocrine carcinoma (NEC) of the larynx with associated Lambert-Eaton myasthenic paraneoplastic syndrome (LEMS). A 68-year-old male patient presented with severe dysphonia and dysphagia. He underwent a total laryngectomy and the excised lesion was extremely large. A pathological examination demonstrated ‘morphological findings of a poorly differentiated carcinoma (G3) with aspects of neuroendocrine differentiation’ (i.e. a poorly differentiated neuroendocrine carcinomas [PD-NEC]). Based on the patient’s medical history and the immunohistochemical findings, he was treated with three cycles of neoadjuvant chemotherapy (cisplatin–etoposide) and then radiotherapy with a total dose of 70 Gy. Of the 10 cases of paraneoplastic syndrome (PNS) related to laryngeal NEC reported in the literature, nine of these syndromes were of an endocrine type. Only one case of PNS associated with laryngeal cancer had a neurological manifestation, which was LEMS. To the best of our knowledge, this current case has only one similar precedent in the literature and it is the second report of an association between a PD-NEC and LEMS. Laryngeal NECs are rare lesions with different prognostic characteristics. The diagnosis should be made using an endocrinological, neurological, radiological and histological multidisciplinary approach. A radical surgical approach is recommended.

Small-Cell Neuroendocrine Tumor of Larynx: A Rare Presentation

Here we report a 60 year aged male presented with complaints of right neck swelling of 3 months duration, swelling was initially small in size and gradually increasing. On examination right level II, hard mobile lymph node was palpable measuring 4 × 4 cm in size, oral cavity and oropharynx was normal. Computed tomography of face neck showed moderately enhancing soft tissue mass of 2 × 3 cm in the supra glottis and left level II cervical lymphadenopathy of size 5 × 5 cm with infiltrating into left sternomastoid muscle. Direct laryngoscopy revealed an ulcero proliferative growth in the supra glottis extending into vallaculla biopsy from the growth showed small round cells with scant amount of cytoplasm with hyperchromatic nucleus, atypical mitosis and at places rosettoid arrangement was seen. Immunohistochemistry with pancytokeratin, CD 56 and synaptophysin were positive, LCA was negative and Ki 67 was >70 %, features consisted with neuroendocrine carcinoma small cell type. Computed tomography of chest, abdomen and pelvis was normal. Finally it was labeled as localized neuro endocrine carcinoma small cell type of larynx (supraglottis). This patient treated with external beam radiotherapy 70 Gy in 35 fractions @ 2 Gy per fraction over 7 weeks along with concurrent chemotherapy with weekly cisplatin followed by adjuvant chemotherapy with Cisplatin and Etoposide for six cycles.

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.

A common classification framework for neuroendocrine neoplasms: an International Agency for Research on Cancer (IARC) and World Health Organization (WHO) expert consensus proposal

The classification of neuroendocrine neoplasms (NENs) differs between organ systems and currently causes considerable confusion. A uniform classification framework for NENs at any anatomical location may reduce inconsistencies and contradictions among the various systems currently in use. The classification suggested here is intended to allow pathologists and clinicians to manage their patients with NENs consistently, while acknowledging organ-specific differences in classification criteria, tumor biology, and prognostic factors. The classification suggested is based on a consensus conference held at the International Agency for Research on Cancer (IARC) in November 2017 and subsequent discussion with additional experts. The key feature of the new classification is a distinction between differentiated neuroendocrine tumors (NETs), also designated carcinoid tumors in some systems, and poorly differentiated NECs, as they both share common expression of neuroendocrine markers. This dichotomous morphological subdivision into NETs and NECs is supported by genetic evidence at specific anatomic sites as well as clinical, epidemiologic, histologic, and prognostic differences. In many organ systems, NETs are graded as G1, G2, or G3 based on mitotic count and/or Ki-67 labeling index, and/or the presence of necrosis; NECs are considered high grade by definition. We believe this conceptual approach can form the basis for the next generation of NEN classifications and will allow more consistent taxonomy to understand how neoplasms from different organ systems inter-relate clinically and genetically.

Structural biology of intraepithelial neuroendocrine cells in the larynx: Literature review

Current knowledge of laryngeal neuroendocrine cells in man and other vertebrates is reviewed. Particular attention is paid to differences in the distribution of neuroendocrine cells between squamous and respiratory laryngeal mucosa, foetal versus post-natal spatial arrangements, relation to the laryngeal cavity and nerve fibres, and immunoreactivities of these cells. Methodological deficiencies and gaps in knowledge are outlined. Comparisons with neuroendocrine cells in lung and gut are drawn, caution with regard to existing histogenetic models of laryngeal neuroendocrine neoplasia is advised and lines of future research are suggested.

P53 Gene Mutation Identified by Next Generation Sequencing in Poorly Differentiated Neuroendocrine Carcinoma of the Nasal Cavity

Neuroendocrine carcinomas (NECs) are epithelial neoplasms showing morphologic, immunophenotypic or ultrastructural evidence of neuroendocrine differentiation. The 2017 WHO Classification of Head and Neck Tumours classifies NECs into well, moderately and poorly differentiated NECs according to light microscopic features, mitotic rate and presence of tumour necrosis. In this study, we performed next generation sequencing (NGS) using a targeted 161 cancer gene panel on a poorly differentiated NEC of the nasal cavity. The tumour was composed of large cells arranged in poorly formed glands and solid nests. The mitotic count rate was 30/10 HPFs and p53 protein was strongly expressed in all tumour cells. NGS identified a missense mutation, c.764T > G (p.Ile255Ser) in the TP53 gene with an allele frequency of 85%. This mutation results in an isoleucine to serine substitution and a non-functional protein. No other mutations were identified. These results suggest that TP53 mutations may drive oncogenesis in poorly differentiated NECs of the head and neck.

A Calcitonin-Producing Neuroendocrine Tumor of the Larynx: A Case Report

A moderately differentiated neuroendocrine carcinoma of the larynx is described. Although the patient had normal serum calcitonin level 36 months before, its level was elevated at the time the neck node was removed. This study supports the hypothesis that a diagnosis of calcitonin-producing neuroendocrine tumor of the larynx with increased plasma calcitonin is possible and should be considered to avoid unnecessary thyroidectomy.

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

Primary neuroendocrine carcinomas (NECs) of the larynx and head and neck are an uncommon and heterogeneous group of neoplasms categorized by the 2017 WHO Classification of Head and Neck Tumors as: (a) well-differentiated (WD-NEC), (b) moderately-differentiated (MD-NEC), and (c) poorly-differentiated (PD-NEC) with small cell and large cell types. The classification incorporates elements of differentiation and grading and closely correlates to the 5-year disease specific survival of 100, 52.8, 19.3 and 15.3% for each diagnostic category. These survival rates are based on historical data limited by the previous lack of standard pathologic diagnostic criteria. The classification has de-emphasized the use of the terms "carcinoid" and "atypical carcinoid" as diagnostic categories. The adoption of uniform pathologic criteria for the classification of NECs of the head and neck should enable the design of high quality studies in order to understand the molecular alterations of these neoplasms.

Unusual cardiac paraganglioma mimicking an atypical carcinoid tumor of the lung

We present a case of unusual cardiac paraganglioma (PG) initially misdiagnosed as atypical carcinoid tumor of the lung and discuss key clinical and pathologic characteristics that guide surgical management of these rare chromaffin cell tumors. A 64-year-old female with persistent cough and back pain was found to have a 4 cm × 3 cm mass abutting multiple cardiopulmonary structures. A biopsy was performed at an outside institution and pathology reported "atypical neuroendocrine carcinoma, consistent with carcinoid". The patient was transferred to our institution and pericardial resection with right pneumonectomy was performed to excise the tumor. Histology of the mass was that of PG with multiple ethanol embolizations. Immunohistochemical examination revealed that type I (chief) cells were positive for neuroendocrine markers (chromogranin A and synaptophysin), while type II (sustentacular) cells were positive for S100. There was no evidence of atypical carcinoid tumor in the lung. PG is an entity of chromaffin cell tumors that often affects the adrenal glands and carotid body. PG rarely occurs in the thoracic region, accounting for just 1-2% of all PG. Proper diagnosis of cardiac PG is challenging owing to its rare prevalence, subtle symptoms of presentation, and the neuroendocrine histopathological features it shares with atypical carcinoids. These tumors are typically benign and are best treated by surgical resection. Our report examines the approach to appropriate diagnosis of cardiac PG vs. atypical carcinoid, preoperative management, and surgical treatment by describing successful resection through thoracotomy without the use of cardiopulmonary bypass.

Clinical recommendations on the treatment of neuroendocrine carcinoma of the larynx: A meta-analysis of 436 reported cases

BACKGROUND

Current recommendations on the treatment of neuroendocrine carcinoma of the larynx (NCL) are based on anecdotal evidence. With this meta-analysis, our purpose was to provide clinicians with more substantiated guidelines in order to improve the treatment outcome of the patients affected with NCL.

METHODS

A structured literature search for all research concerning NCL was performed against the MEDLINE and EMBASE databases. Available data was normalized, pooled, and statistically analyzed.

RESULTS

Four hundred thirty-six cases of NCL were extracted from 182 studies, of which 23 were typical carcinoid, 163 were atypical carcinoid, 183 were small-cell neuroendocrine carcinoma, 29 were large-cell neuroendocrine carcinoma, and 38 were unspecified carcinoid tumors. The 5-year disease-specific survival (DSS) was 100% for typical carcinoid, 53% for atypical carcinoid, 19% for small-cell neuroendocrine carcinoma, and 15% for large-cell neuroendocrine carcinoma (p < .001). Patients with an atypical carcinoid treated with surgery had better DSS than those treated with radiotherapy (60% vs 54%; p = .035). Postoperative radiotherapy did not result in better DSS in atypical carcinoid. Patients with an atypical carcinoid, not undergoing surgical treatment of the neck, developed isolated regional recurrence in 30% of cases (p = .001). Radiochemotherapy yielded the best DSS for small-cell neuroendocrine carcinoma compared to other modalities (31% vs 13%; p = .001).

CONCLUSION

Typical carcinoid can be treated by local excision alone. Atypical carcinoids do not seem to respond well to radiotherapy and are best managed through radical surgical excision in combination with elective neck dissection. Patients with small-cell neuroendocrine carcinoma or large-cell neuroendocrine carcinoma seem to benefit most from chemoradiotherapy.

Neuroendocrine neoplasms of the head and neck: some suggestions for the new WHO classification of head and neck tumors

As knowledge and understanding in pathology evolve, classifications and nomenclature also change to reflect those advances. The 2005 World Health Organization Classification of Head and Neck Tumours was a significant step towards diagnostic standardization of head and neck neuroendocrine carcinomas; however, in the last 10 years there have been new data supporting the recognition of "large cell neuroendocrine carcinoma" as a distinctive high grade carcinoma in the head and neck, a lesion not included in the 2005 Classification. In addition, the terms "middle ear adenoma" and "carcinoid tumor of middle ear" are still widely used to describe a neoplasm that is neither a pure adenoma nor a carcinoid tumor but a lesion with variable mixed exocrine and endocrine differentiation. Largely using the diagnostic criteria of the WHO classification of neuroendocrine carcinomas of the lung, we propose the terms "neuroendocrine carcinoma, grade 1"; "neuroendocrine carcinoma, grade 2"; "neuroendocrine carcinoma, grade 3, large cell type"; and "neuroendocrine carcinoma, grade 3, small cell type" for the classification of neuroendocrine carcinomas of the head and neck in a future WHO classification. In addition, we also proposed the term "mixed epithelial neuroendocrine tumor" of the middle ear as an alternative for "middle ear adenoma" and "carcinoid tumor of the middle ear".

HPV-associated neuroendocrine carcinoma of the oropharynx: a rare new entity with potentially aggressive clinical behavior

High-grade neuroendocrine carcinoma of the head and neck is an aggressive neoplasm which rarely arises in the oropharynx. Here we report a series of 8 oropharyngeal neuroendocrine carcinomas associated with both human papillomavirus (HPV) infection and tobacco exposure. The tumor occurred predominantly in male patients (6 of 8) at a mean age of 59 years. Histologically, these cases were all classified as poorly differentiated neuroendocrine carcinoma (small cell carcinoma) with high mitotic activity [mean 53.3 mitoses per 10 HPF], necrosis, high nuclear-to-cytoplasmic ratio, and nuclear molding. One case also exhibited a moderately differentiated component, and one other case had a component of squamous cell carcinoma with basaloid features. Neuroendocrine differentiation was confirmed by immunoreactivity for synaptophysin and/or chromogranin A in all cases. P63 staining was negative, except in 1 case. Seven of the 8 cases showed strong and diffuse p16 expression, a surrogate marker for high-risk HPV infection. HPV infection was confirmed in 6 of these 7 cases by HPV in situ hybridization and/or polymerase chain reaction analysis. HPV subtypes 16, 18, and 33 were identified in 1 case each by polymerase chain reaction testing. Six of the 7 patients for whom clinical history was available presented with advanced disease (4 with regional lymph node metastases, 1 with distant metastases, and 1 with distant and locoregional metastases). Disease recurred in 5 of the 6 patients with available clinical follow-up, with 3 developing distant metastases to brain, bones, lung, pleura, adrenal glands, and pancreas. These 3 cases were all from the HPV-positive group. In summary, neuroendocrine carcinoma of the oropharynx represents a rare novel HPV-associated entity with high-grade histologic features and aggressive clinical behavior.

Terminology and classification of neuroendocrine neoplasms of the larynx

OBJECTIVES

To review the history and literature on neuroendocrine neoplasms of the larynx and discuss the terminology and classification of these tumors.

STUDY DESIGN

Contemporary review.

METHODS

Published journal articles identified through PubMed and conference proceedings were reviewed.

RESULTS

Neuroendocrine neoplasms of the larynx include both epithelial (carcinomas) and neural-type lesions (paragangliomas).The nomenclature of these tumors has changed quite a bit over time, but recently, clearer categories have emerged that are biologically meaningful. They can overlap clinically and histologically so that segregation into the clinically relevant subtypes can be difficult, but it is extremely important to do so as they have a wide range of behaviors going from benign to rapidly fatal.

CONCLUSIONS

Neuroendocrine neoplasms of the larynx can be clearly categorized into the five tumor types: typical carcinoid, atypical carcinoid, small cell neuroendocrine carcinoma, large cell neuroendocrine carcinoma, and paraganglioma. These have concrete biologic and clinical significance and clearly dictate patient treatment.

Large cell neuroendocrine carcinoma of the larynx: definition of an entity

Laryngeal atypical carcinoids (AC/moderately-differentiated neuroendocrine carcinoma) are associated with moderately aggressive clinical behavior; however, a subset of tumors classified as AC have much greater aggressive potential. These tumors fulfill the proposed diagnostic criteria for pulmonary large cell neuroendocrine carcinoma, albeit in the larynx. In the current WHO classification, laryngeal large cell neuroendocrine carcinomas (LCNEC) are classified as variants of AC, whereas pulmonary LCNEC are classified as poorly-differentiated neuroendocrine carcinomas. Reported outcomes for pulmonary tumors support the separate classification of LCNEC. Five and ten year survival rates for pulmonary AC are 61-73, and 35-59%, respectively, while the 5-year survival rate for pulmonary LCNEC is as low as 30%. By extension, we postulate that the biologic potential of laryngeal LCNEC is similar to that of small-cell carcinoma (poorly-differentiated neuroendocrine carcinoma), and as such, warrants reclassification. The files of Barnes Jewish Hospital/Washington University were searched for the term "neuroendocrine" and the anatomic subsite larynx. Neuroendocrine carcinoma cases were evaluated using the WHO definitions for pulmonary AC and LCNEC; small cell carcinoma was excluded. Cases were also solicited from the larger head and neck pathology community. A literature search was also performed for cases of laryngeal neuroendocrine carcinoma, and cases which could be clearly classified as LCNEC by this scheme were captured as well. Six new cases plus four reported cases were identified which fulfill the WHO criteria for pulmonary LCNEC (eight men and two women). Nine patients presented at stage IV and 88% died of disease (DOD), 75 and 100% of these at 2 and 3 years, respectively. Laryngeal LCNEC is a rare entity, distinct from AC. We recommend that laryngeal tumors fulfilling WHO criteria for pulmonary LCNEC not be classified as variants of AC, but as variants of small cell carcinoma (poorly-differentiated neuroendocrine carcinoma) as they are associated with poorer outcome.

KIT and platelet-derived growth factor receptor α gene expression in laryngeal small cell carcinoma

Objective:

Small cell carcinoma has the worst prognosis of all laryngeal neoplasms. In order to further characterise this tumour, with a view to development of new therapeutic approaches, we report the results of KIT gene and platelet-derived growth factor receptor α gene expression analysis, for two extremely rare cases of primary small cell carcinoma of the larynx.

Method:

Case reports, including immunohistochemical study, and review of the literature.

Results:

We present two patients with laryngeal small cell carcinoma, who died from tumour metastasis to the lungs and brain despite aggressive treatment. Immunohistochemical studies revealed positive reactions for KIT gene expression and platelet-derived growth factor α gene expression in patient one, and for KIT gene expression in patient two. Molecular genetic analysis, using polymerase chain reaction direct sequencing, identified no mutations of the KIT or platelet-derived growth factor receptor α genes.

Conclusion:

Although further investigation is necessary regarding KIT gene expression and platelet-derived growth factor receptor α gene expression in laryngeal small cell carcinoma, the reported results suggest that these genes may be significant in the development of molecular targeted therapy.

Moderately differentiated neuroendocrine carcinoma of the larynx

CONCLUSIONS

Laryngeal moderately differentiated neuroendocrine carcinoma (LMDNEC) is an aggressive and uncommon malignancy. Thorough histological evaluation is the key to correct diagnosis and differentiation. Complete surgical resection of laryngeal primary lesions and suitable neck dissection of cervical nodes provide reasonable therapy, and postoperative radiotherapy should also be considered.

OBJECTIVE

To explore the diagnosis and treatment of LMDNEC.

METHODS

Clinical information regarding patient, presentation, immunohistochemical results, treatment, and outcome was obtained through review of patients' charts. Follow-up until the time of death or last contact with us was obtained for all patients.

RESULTS

Eight patients (six males, two females) were pathologically confirmed to have LMDNEC between 2000 and 2008 in our hospital. Patients presented with throat pain, hoarseness, dysphagia, and neck mass, and all tumors originated in the supraglottis. Six of the eight patients (all males) had a history of cigarette smoking. Pathologically, the tumors frequently had positive immunoreactivity for Chg A (6/8), Syn (7/8), NSE (7/8), and CK (8/8). Two patients died of distant metastasis and tumor recurrence in the neck, respectively, the other six cases were still in follow-up.

Neuroendocrine neoplasms of the larynx: an overview

Neuroendocrine neoplasms of the larynx are rare but are the most common nonsquamous tumors of this organ. In the past, there has been considerable confusion about the nature and classification of these neoplasms, but the current consensus is that there are 4 different types of laryngeal neuroendocrine tumors composed of paraganglioma, typical carcinoid, atypical carcinoid tumor, and small cell neuroendocrine carcinoma. Carcinoids and small cell neuroendocrine carcinomas are epithelial neoplasms, whereas paragangliomas are of neural origin. Diagnosis is based primarily on light microscopy and confirmed by immunohistochemistry and electron microscopy. Precise diagnosis is essential because the natural history, treatment, and prognosis vary widely for the different neoplastic categories. Typical carcinoids are very rare and are treated by wide local excision, usually partial laryngectomy, without elective neck dissection. Atypical carcinoid tumors are more common and more aggressive. They are treated by partial or total laryngectomy with elective or therapeutic neck dissection. Adjuvant chemo/radiotherapy may be of benefit in some cases. Small cell neuroendocrine carcinomas are highly aggressive and should be considered disseminated at initial diagnosis. The treatment is by irradiation and chemotherapy as surgery has proven to be of a little benefit. Paragangliomas are treated by local excision or partial laryngectomy. It is difficult to determine the valid survival statistics for typical carcinoids because of their rarity and confusion in the literature with their atypical counterparts. They have a greater tendency to metastasize, and thus a worse prognosis than was previously believed. Atypical carcinoid tumors have a 5-year survival rate of approximately 50%, which decreases with time. The prognosis of small cell neuroendocrine carcinoma of the larynx is dismal, with 5-year survival rates of 5%. The biological behavior of laryngeal paraganglioma is generally benign and the prognosis is excellent.

Undifferentiated malignant neoplasms of the sinonasal tract

CONTEXT

The most commonly encountered malignant neoplasms of the sinonasal tract are the keratinizing and nonkeratinizing types of squamous cell carcinoma. However, this complex anatomic region may represent the site of aggressive, non-squamous cell epithelial and nonepithelial malignant neoplasms of varying histogenesis, which are grouped under the term undifferentiated malignant neoplasms. Frequently, these undifferentiated malignancies share clinical and light microscopic features, which makes differentiation of one from the other virtually impossible without the use of adjunct analyses (eg, immunohistochemistry, electron microscopy, or molecular biologic studies). These tumors often are clinically aggressive and usually fatal, despite all attempts at controlling disease. Nevertheless, differentiating these tumors has clinical import because advances in therapeutic intervention may increase survival with good quality of life, and in some instances may achieve a cure.

OBJECTIVE

To compare and contrast the clinical, light microscopic, and immunohistochemical features of sinonasal undifferentiated malignant neoplasms.

DATA SOURCES

Case-derived material and literature review.

CONCLUSIONS

A variety of undifferentiated malignant neoplasms occur in the sinonasal tract with overlapping clinical and pathologic findings. In limited biopsy material, differentiation of these tumor types can be challenging. The pathologist plays a primary role in establishing the correct diagnosis, which often necessitates the use of adjunct studies that allow for differentiating among these neoplasms.

Primary carcinoid tumour of nasal septum

OBJECTIVE

We present the first reported case of primary carcinoid tumour of the nasal septum.

METHOD

Case report of our experience of a carcinoid tumour of the nasal septum. We discuss our clinical, radiological and pathological findings.

RESULT

An 83-year-old woman presented with a history of left-sided nasal blockage. Clinical examination showed a unilateral, left-sided nasal polyp. Further imaging and histological analysis confirmed this to be a carcinoid tumour. Carcinoid tumours outside the gastrointestinal tract are rare. There have been reports of carcinoid tumours in the head and neck region, but no published cases occurring in the nasal septum. Our management involved wide surgical resection with regular follow up to monitor for recurrence and for the development of carcinoid syndrome. Four years from initial presentation, the patient remained free of the primary tumour and had displayed no signs or symptoms suggestive of carcinoid syndrome.

CONCLUSION

To the authors' best knowledge, and after searching the world literature, the presented case represents the first report of primary carcinoid tumour of the nasal septum. Despite its rarity, this tumour should be considered as part of the differential diagnosis, as timely recognition and intervention are critical for successful treatment.

Carcinoid tumor of the larynx: clinical analysis of 33 cases in Japan

CONCLUSION

In regard to the treatment of carcinoid tumor of the larynx, irradiation is not effective and tumor excision with a minimum surgical margin is associated with a high risk of local recurrence. Lymph node metastases to the neck are associated with worsening of the prognosis. To improve the survival rate, primary resection with a sufficient surgical margin (e.g. partial laryngectomy) and (elective) neck dissection is recommended, even for patients with early stage carcinoid tumors of the larynx.

OBJECTIVE

The objective of this study was to clarify the prognostic factors, modalities of treatment for the primary lesions, and importance of neck dissection in the treatment of carcinoid tumors of the larynx.

PATIENTS AND METHODS

The data of 33 cases of carcinoid of the larynx reported from Japan (including 2 of our cases) were analyzed.

RESULTS

The distributions of the T and N classifications of the lesions were as follows T1, 50.0%; T2, 32.2%; T3, 14.3%; T4, 3.6%; N0, 57.1%; N1, 17.9%; N2, 25.0%; and N3, 0%. Fifteen patients underwent radiation therapy, of whom five underwent curative radiotherapy. While complete remission (CR) was maintained in one of these patients (T1N0), the remaining four patients developed recurrence. Five patients underwent preoperative radiation therapy. The response to the treatment was rated as no change in four patients and as progressive disease in the remaining one patient. Among the patients with N0 disease, seven patients (43.8%) developed lymph node metastases in the neck postoperatively. Distant metastases were the most frequent cause of death in the patients. The 3-year, 5-year, and 10-year survival rates of the patients were 58.5%, 36.5%, and 12.2%, respectively. Significant differences were recognized in the survival rates between patients with and without neck lymph node involvement at the first treatment (p=0.008), and between patients with and without postoperative lymph node recurrence in the neck (p=0.037).

Small cell carcinoma of the head and neck: a review

Small cell carcinoma (SCC) has become recognized as a distinct, though relatively infrequent, clinical pathology that occurs in multiple sites throughout the head and neck. Excluding cases that are considered to arise from skin, SCC in the head and neck has been found to develop in nearly all structures associated with the upper aerodigestive tract. Among the head and neck sites, the frequency of SCC is greatest in the larynx, with salivary glands and the sinonasal region comprising the other principle areas of origin. Controversy exist as to whether SCC can develop as a distinct entity in the thyroid, with most tumors that previously would have been considered as SCC now found to be lymphomas or variant forms of other types of thyroid malignancy. While there seems to be some differences among tumors arising from the various subsites, in general all SCC that originate in the head and neck have a tendency for aggressive local invasion and a strong propensity for both regional and distant metastasis. Treatment may include surgical resection, radiotherapy, chemotherapy, or some combination of these modalities. Due to the infrequency of these tumors, it is very unlikely that any large, controlled study will ever be done. For this reason, recommendations for treatment of SCC arising in the head and neck are based primarily on retrospective data from various small case series and on comparative data for treatment of SCC of bronchogenic and other extrapulmonary origin. Although patients with truly limited local disease may enjoy some prolonged survival, most patients with this tumor do poorly despite all current attempts at treatment.

Neuroendocrine neoplasms of the larynx: Advances in identification, understanding, and management

While 85-90% of laryngeal malignancies prove to be squamous carcinomas, the second most common tumour type found in the laryngeal region will prove to be a member of the family of neuroendocrine tumours. Laryngeal carcinoid tumours have a capacity for metastasis, and so are more aggressive tumours than their light microscopic features might imply--5-year survival rates are in the vicinity of 50%. Laryngeal atypical carcinoid tumours are lesions with a well-recognized capacity for local recurrence as well as metastasis, with a 5-year survival of just under 50%. Laryngeal small cell neuroendocrine carcinomas are particularly aggressive tumours, with a 5-year survival of no more than 5-10%. Laryngeal paragangliomas are lesions without any real capacity for metastasizing. Surgical excision is the mainstay of treatment of carcinoid tumours, atypical carcinoid tumours, and paragangliomas. Small cell neuroendocrine carcinomas are chiefly treated by way of radiation and chemotherapy; the role of adjuvant therapy in the treatment of atypical carcinoid tumours remains to be established.

Primary Carcinoid Tumor of the Parotid Gland: A Case Report and Review of the Literature

Salivary gland tumors account for 3 to 6% of all head and neck neoplasms in adults. Some 70 to 85% of these lesions are found in the parotid. Carcinoid tumors, which represent a distinct and relatively uncommon subset of neuroendocrine tumors, are most commonly found in the gastrointestinal tract, although in rare cases they are known to occur in extragastrointestinal locations, including the larynx, middle ear, and pancreas. Malignancies of the parotid gland are uncommon (approximately 25% of parotid neoplasms), and to the best of our knowledge, a primary carcinoid tumor of the parotid has not been previously described in the literature. Reports of parotid carcinoid tumors during the past 30 years have described the presence of nonparotid primary carcinoid tumors (usually gastrointestinal) that had been diagnosed and treated several years prior to the presentation of the parotid lesion. Under such circumstances, the parotid lesion may be assumed to have been a metastatic rather than a primary carcinoid. This report documents what we believe is the first case of a primary carcinoid tumor of the parotid gland. We detail the clinical, surgical, radiologic, immunologic, and histochemical findings associated with its diagnosis, and we describe our management of this case. Although a primary carcinoid in this location is exquisitely rare, knowledge of such lesions is important because their management is substantially different from that of other parotid tumors. In particular, it is important to differentiate them from metastatic tumors from other sites.

The spectrum of endocrinocarcinomas of the larynx

The authors discuss the terminology, classification, pathology, diagnosis, treatment and prognosis of the endocrinocarcinomas of the larynx.

Moderately Differentiated Neuroendocrine Carcinoma (Atypical Carcinoid) of the Larynx: A Clinically Aggressive Tumor

OBJECTIVES

To evaluate the presentation, treatment, and outcome of a small series of patients with moderately differentiated neuroendocrine carcinoma (MDNC) of the larynx seen at one institution and to provide information on this uncommon laryngeal malignancy for therapeutic decision making.

STUDY DESIGN

Retrospective analysis of medical records. Cases were identified from databases maintained by the medical informatics and pathology departments.

METHODS

Patient, tumor, treatment, and outcome data were collected from medical records. Main outcome measures were recurrence, overall and disease-specific survival, and cause of death.

RESULTS

Eleven patients (6 males; 5 females) seen between 1990 and 2003 had sufficient documentation for further evaluation. Patients presented with dysphagia, throat pain, or hoarseness, and all tumors arose in the supraglottis. Eight of 11 patients gave a history of cigarette use. Of the 10 patients treated with curative intent, 7 who recurred all died with disease. The average disease-free interval was 54 months, with a range of 2 to 101 months. The overall and disease-specific survival was 64 and 54 months, respectively. Nine patients were alive 3 years after diagnosis. No correlations with age, stage at presentation, or initial treatment modality and outcome (recurrence or survival) were found.

CONCLUSIONS

Laryngeal MDNC is an aggressive malignancy with frequent regional and distant metastases. Although surgical resection is usually recommended, patients did respond to radiation and chemotherapy, suggesting a combined approach may be indicated. Aggressive initial therapy is needed because development of recurrence portends a poor outcome.

Large cell neuroendocrine carcinoma of the larynx: a case report and a review of the classification of this neoplasm

This report describes a case of large cell neuroendocrine carcinoma (LCNEC) of the larynx. A 74 year old man who presented with otalgia underwent direct laryngoscopy with biopsy, which revealed an invasive poorly differentiated carcinoma. Laryngectomy with bilateral neck dissections revealed invasion of the pre-epiglottic space by the tumour, with metastases to bilateral lymph nodes (AJCC T3N2c). The tumour was characterised by large cells with vesicular chromatin and prominent nucleoli. The cells were arranged in organoid and trabecular patterns with a background of extensive necrosis and numerous mitotic figures. Immunohistochemical and ultrastructural analyses confirmed the neuroendocrine nature of the tumour. Metastatic disease was present in the liver, and the patient died within weeks of surgery. LCNEC carcinoma is a rare tumour of the larynx. Recognition at this site is essential so that proper patient management can be initiated.

Endoscopic CO2 laser surgery for an atypical carcinoid tumor of the epiglottis masquerading as a supraglottic cyst

BACKGROUND

Atypical carcinoid tumor is a neuroendocrine tumor; its occurrence in the larynx is uncommon, and clinical manifestations are rare. We report an unusual case of atypical carcinoid tumor of the epiglottis mimicking a supraglottic retention cyst.

METHODS

A 44-year-old woman complained of an intermittent globus sensation of the throat of 2 years' duration. A 1.0- x 0.8-cm cystic lesion was found over the tip of the epiglottis. A supraglottic retention cyst was initially diagnosed, and the patient was treated medically. Her symptoms persisted, so we performed a laryngoscopic biopsy, which suggested an atypical carcinoid tumor.

RESULTS

Transoral endoscopic CO2 laser surgery and bilateral elective neck dissection were subsequently performed. The 2-year follow-up did not reveal any locoregional recurrence or distant metastasis.

CONCLUSIONS

This aggressive neoplasm may cause only a few, unremarkable symptoms and masquerade as a supraglottic cyst. Endoscopic CO2 laser surgery can be used to resect this uncommon tumor, with oncologically sound results and without surgical morbidity.

Endocrinocarcinomas (carcinoids and their variants) of the duodenum. An evaluation of 927 cases

This study was undertaken to supplement our previous analysis of 635 duodenal carcinoids to give both wider and different viewpoints on a larger series of duodenal endocrinocarcinomas, and to provide up-to-date clinicopathologic information regarding these neoplasms. A total of 927 cases of such neoplasms of the duodenum were collected from the Niigata Registry for gut-pancreatic endocrinomas, consisting of the carcinoid group with 897 cases, 857 typical carcinoids and 40 atypical varieties, and the variant group with 30 remaining endocrinocarcinomas expressed by various terminology. Significant statistical differences between these two groups were evident in various aspects: in sites of tumor growth, aggressiveness of invasion to the extra-duodenal structures, rates and sites (liver, lymph nodes and bone) of metastases, average tumor-size, immunohistochemistry of gastrin and serotonin, rates of recurrence, five-year survival rates and others. In addition, a close similarity between these two groups was noted in several aspects of histology, histochemistry and immunohistochemistry, rendering the variant group in a member of the carcinoid family. Regarding the carcinoid group in comparison with that in other organs may be summarized as follows: a reasonable male/female ratio of 1.39, a reasonable average age of 55.9 years, a high typical/atypical ratio of 21.4, a relatively small average tumor-size of 17.7 mm, a relatively low metastasis rate of 27.4%, a high histologic B-type dominance of 75.5%, a high postoperative survival rate of 83.3% and a reasonable incidence of the carcinoid syndrome of 3.1%.

A Study of Moderately Differentiated Neuroendocrine Carcinomas of the Larynx and an Examination of Non-Neoplastic Larynx Tissue for Neuroendocrine Cells

OBJECTIVES/HYPOTHESIS

To determine the most appropriate terminology for neuroendocrine carcinomas (NEC) of the larynx, successive clinicopathologic studies are encouraged. The typical location and immunophenotype of laryngeal NEC raise a question of whether any precursor cells exist.

STUDY DESIGN

Six patients with laryngeal NEC were analyzed. Another 20 laryngectomy specimens were examined for the presence of non-neoplastic neuroendocrine cells.

METHODS

Tumor morphology and patient outcome were determined, and tumor tissue underwent immunohistochemical examination to identify cytokeratin, neuroendocrine markers (chromogranin, synaptophysin, CD56, calcitonin), S-100 protein, and p53 protein. A neuroendocrine marker study was also performed on non-neoplastic regions of another 20 laryngectomy specimens to identify any neuroendocrine cells.

RESULTS

Laryngeal NEC, all submucosal, exhibited various morphology with or without histologic evidences of neuroendocrine differentiation. The tumors showed frequent (67%) calcitonin expression, calcitonin secretion in one case, and common (50%) p53 over-expression. Three patients died within 3 years. In the non-neoplastic larynx specimens, Kulchitsky cell-like bipolar neuroendocrine cells were identified in the basal and middle layer of the respiratory epithelium of the ventricle and subglottis but none in the submucosal layer of the supraglottic region. The neuroendocrine cells did not express calcitonin.

CONCLUSIONS

Moderately differentiated or large-cell NEC is a more favored term than atypical carcinoid until more refined classifications for upper respiratory tract NEC are agreed on. Despite the confirmed presence of neuroendocrine cells in the respiratory epithelium of the larynx, the origin of laryngeal NEC remains unknown. p53 mutation might be one of the major molecular steps in the pathogenesis of laryngeal NEC.

Thyroid transcription factor-1, but not p53, is helpful in distinguishing moderately differentiated neuroendocrine carcinoma of the larynx from medullary carcinoma of the thyroid

Moderately differentiated neuroendocrine carcinoma/atypical carcinoid tumor is the most common nonsquamous malignancy in the larynx; however, due to morphologic overlap and calcitonin immunoreactivity, it can be difficult to distinguish from thyroid medullary carcinoma. Currently, low serum calcitonin is the most reliable means for distinguishing primary laryngeal moderately differentiated neuroendocrine carcinoma from metastatic medullary carcinoma. Thyroid transcription factor-1 (TTF-1) is positive in at least 80% of medullary carcinomas, but has not been evaluated in laryngeal moderately differentiated neuroendocrine carcinomas. Additionally, it has been suggested that p53 is positive in laryngeal moderately differentiated neuroendocrine carcinomas and negative in other neuroendocrine tumors, but this has not been validated. The purpose of this study was to determine if the immunohistochemical markers TTF-1 and p53 could be used to discriminate between laryngeal moderately differentiated neuroendocrine carcinomas and thyroid medullary carcinomas. Eight laryngeal moderately differentiated neuroendocrine carcinomas and 10 thyroid medullary carcinomas were identified from the archival files of the BWH and MGH Pathology Departments. Hematoxylin and eosin slides were reviewed, and immunohistochemistry was performed using antibodies to calcitonin, TTF-1, and p53. Calcitonin immunohistochemistry demonstrated immunoreactivity in 100% of laryngeal moderately differentiated neuroendocrine carcinomas (N=8) and 100% of thyroid medullary carcinomas (N=10). There was weak, focal immunoreactivity with TTF-1 in one of eight (13%) laryngeal moderately differentiated neuroendocrine carcinomas, whereas nine of ten (90%) medullary carcinomas were positive for TTF-1, with strong diffuse staining in seven of these cases (78%). p53 was positive in three of six (50%) laryngeal moderately differentiated neuroendocrine carcinomas, and three of ten (30%) medullary carcinomas. Our data demonstrate that immunoreactivity for TTF-1, but not calcitonin or p53, may be helpful in distinguishing laryngeal moderately differentiated neuroendocrine carcinoma and thyroid medullary carcinoma. In particular, diffuse and/or strong TTF-1 immunoreactivity favors a diagnosis of primary thyroid medullary carcinoma over laryngeal moderately differentiated neuroendocrine carcinoma.

Infiltrating, Moderately Differentiated Neuroendocrine Tumor of the Larynx: A Brief Report

We report a rare case of moderately differentiated neuroendocrine carcinoma of the larynx. We describe the clinical and pathologic findings relevant to this case, and we review the literature on the pathologic features of this malignancy. We also discuss treatment options.

Neuroectodermal neoplasms of the head and neck with emphasis on neuroendocrine carcinomas

Tumors exhibiting neuroectodermal differentiation occur throughout the body, and the diverse tissues of the head and neck give rise to a wide assortment of these neoplasms. Neuroectodermal neoplasms may be divided into lesions showing primarily epithelial differentiation (Group I, neuroendocrine carcinomas) and a more diverse group (Group II) of nonepithelial neoplasms. This article reviews these neuroectodermal tumors of the head and neck with emphasis on the neuroendocrine carcinomas and their nomenclature. The author believes that with regard to Group I tumors, the older terminology of carcinoid, atypical carcinoid, and small cell carcinoma should be replaced by subclassifications of well-differentiated, moderately differentiated, and poorly differentiated neuroendocrine carcinoma. The latter category should be further subdivided into small cell and large cell variants. Neuroendocrine carcinomas, particularly the moderately differentiated subtype, are often underdiagnosed in the head and neck region. In the larynx, these tumors are the most common form of nonsquamous carcinoma. Poorly differentiated neuroendocrine carcinoma of small cell type is most common in the salivary glands but can occur elsewhere in the region. The large cell subtype of poorly differentiated neuroendocrine carcinoma has not been well documented in this region. However, the most likely candidate for this tumor category is the so-called sinonasal undifferentiated carcinoma. Group II tumors discussed include olfactory neuroblastoma, malignant melanoma, and Ewing's sarcoma. In addition, differential diagnostic problems related to Group I and II tumors are reviewed in detail. This article reviews and updates our understanding of neuroectodermal neoplasms arising in the head and neck. The focus is on tumors that exclusively involve this region or show a strong predilection to occur here.

Paragangliomas: classification, pathology, and differential diagnosis

This article discusses the paraganglion system and extra-adrenal paragangliomas. In particular, the clinicopathologic, immunohistochemical, and ultrastructural features of paragangliomas and neuroendocrine neoplasms of the larynx are presented with a discussion of the differential diagnosis.

A review of neuroendocrine neoplasms of the larynx: update on diagnosis and treatment

Neuroendocrine neoplasms of the larynx have been divided into those of epithelial or neural origin. The latter consist of paragangliomas while the epithelial origin group can be divided into the typical and atypical carcinoids and small cell neuroendocrine carcinomata, the latter consisting of the oat cell type, the intermediate cell type and the combined cell type. There are now over 500 cases of neuroendocrine neoplasms of the larynx in the literature. The diagnosis is primarily based on light microscopy, and, in some instances, it may be supported by special histochemical studies. It should be confirmed by immunocytochemical and/or ultrastructural investigation. The different biological behaviour of neuroendocrine neoplasms of the larynx makes a specific diagnosis of paramount importance, since treatment depends on diagnostic accuracy. Typical carcinoid is an extremely rare lesion. It is treated preferably by conservative surgery; elective neck dissection is not necessary because of the lack of lymph node metastases at diagnosis. Chemotherapy and/or radiotherapy have not been effective in the limited number of patients treated thus far. Prognosis is excellent with cure following surgery. Atypical carcinoid is the most frequent non-squamous carcinoma of the larynx. The mainstay of treatment is surgery. Elective neck dissection should be performed because of the high likelihood of cervical lymph node metastases. Primary radiation therapy with adjuvant chemotherapy is not indicated. The survival rate is 48 per cent at five years and 30 per cent at 10 years. Although the larynx is one of its most common extrapulmonary sites, small cell neuroendocrine carcinoma is still a rare tumour. Surgical results for this tumour have been disappointing and is reserved for cases of local relapse with no evidence of metastasis. Chemotherapy and radiotherapy currently appear to offer the least disabling and most effective forms of therapy. The two- and five-year survival rates are 16 per cent and five per cent, respectively. Paraneoplastic syndromes have occasionally been reported in association with carcinoid tumours (typical and atypical) and small cell neuroendocrine carcinoma. There have been also rare reports of an elevated neuropeptide serum level. Paraganglioma is the only laryngeal neuroendocrine neoplasm with a female preponderance (3:1). Confusion with atypical carcinoid has led to incorrect diagnosis and inappropriate classification schemes, erroneously suggesting that laryngeal paraganglioma has the potential for aggressive behaviour. Conservative surgery represents the treatment of choice; elective neck dissection is not necessary, and the prognosis is excellent.

Small cell carcinoma of the larynx: imaging findings

Small cell carcinoma of the larynx is an uncommon epithelial tumor, which is the most aggressive subtype of neuroendocrine carcinomas. Because of its nonspecific clinical and radiological manifestations, the diagnosis of small cell carcinoma of the larynx is essentially based on the light microscopic examination aided by electron microscopy or immunohistochemical staining. We report a case of supraglottic small cell carcinoma accompanied by large bilateral cervical lymph node metastasis ocurring in a 70-year-old man. On CT scans, no area of low attenuation indicating necrosis was demonstrated within such large metastatic lymph nodes. We suggest that small cell carcinoma of the larynx should be included in the diagnostic considerations when a laryngeal mass is accompanied by large cervical lymph nodes without necrosis shown by CT.