A retrospective analysis of molecular testing in cytologically indeterminate thyroid nodules with histologic correlation: Experience at a heterogenous multihospital system

INTRODUCTION

Thyroid malignancy is one of the most common types of cancer in developed nations. Currently, fine-needle aspiration cytology (FNAC) is the most practical screening test for thyroid nodules. However, cytologically indeterminate samples comprise approximately 15%-30% of cases. These include cases classified as atypia of undetermined significance (AUS), follicular neoplasm (FN), and suspicious for malignancy (SFM). Indeterminate cases can be sent for molecular testing for more definitive classification to help guide management and prevent overtreatment of benign thyroid nodules. We conducted a retrospective review on molecular testing of indeterminate thyroid FNAC and reviewed subsequent histologic diagnoses in resection specimens to assess how molecular testing supported a diagnosis and its effect on clinical management of patients at our institution.

METHODS

A retrospective chart review was performed on all thyroid FNAC specimens, corresponding molecular testing, and subsequent surgical resection specimens over a 6-year period.

RESULTS

A total of 10,253 thyroid FNAC were performed in our hospital system during our study period, of which 10% (n = 1102/10,253) had indeterminate FNAC results. Molecular testing was performed in 16% (n = 178/1102) of indeterminate cytology cases. Genetic alterations were identified in 39% (n = 69/178) of the cases sent for molecular testing. The majority of cytologically indeterminate cases sent for molecular testing were follicular-patterned lesions and their corresponding resection specimens revealed mostly low grade follicular derived neoplasms (i.e., follicular adenoma, non-invasive follicular thyroid neoplasm with papillary-like nuclear features, and follicular variant of papillary thyroid carcinoma). Of the cases with identified genetic alterations, 75% (n = 52/69) were treated surgically. In cases with no genetic alterations identified, only 18% (n = 20/109) were treated surgically.

DISCUSSION/CONCLUSION

Molecular testing on cytologically indeterminate thyroid nodules can help provide a more accurate risk of malignancy assessment in patients with lesions that are difficult to diagnosis based solely on FNAC morphology. The types of genetic alterations identified in the resected thyroid lesions were consistent with what has been previously described in the literature. Additionally, we found that in the patients with indeterminate thyroid FNAC with adjunct molecular testing, more than half did not undergo surgical resection. This finding emphasizes the value of adding molecular testing in patients, particularly when attempting to reduce unnecessary surgical intervention.

Intestinal-Type Adenocarcinoma in Head and Neck: Dissecting Oncogenic Gene Alterations Through Whole Transcriptome and Exome Analysis

Adenocarcinomas of the nasal/paranasal sinuses are uncommon, but intestinal-type adenocarcinomas (ITACs) are important. Due to the rarity of these tumors, their molecular profile is not well known. To further investigate the molecular profile and find potential oncogenic drivers, we compared the whole transcriptome and exome of ITACs at different anatomic locations in the head and neck. Twenty-one head and neck adenocarcinomas were used in this study, divided into 10 sinonasal adenocarcinomas (SNT) and 11 extrasinonasal (T) head and neck adenocarcinomas according to anatomic location and histology. Tumor samples along with normal mucosa were microdissected from formalin-fixed, paraffin-embedded samples, and RNA and DNA were subjected to whole-transcriptome and -exome shotgun sequencing. Analysis of ITACs at sinonasal locations showed 410 subtype-specific differentially expressed (DE) genes and noncoding transcripts compared with the group of other anatomic locations, with 2909 subtype-specific DE genes. The groups shared 872 genes, with 17 highly different or opposing DE genes. Whole-exome mutation analysis revealed the gene MLL3 (KMT2C) to be exhibiting the most frequent loss-of-function mutations in all adenocarcinomas investigated. The results suggest that the head and neck ITACs investigated were mainly caused by loss-of-function mutations in MLL3 that disabled chromatin methylation and remodeling of all MLL3-targeted enhancers in the tumors. This changed the activity of multiple genes/gene clusters, supporting oncogenicity mostly via pathways of signaling, dedifferentiation, proliferation, migration, and immune and inflammatory deregulation, indicating a truly epigenetic event as the root cause for the heterogenous diversity of these enteric types of cancer. The data of this study form the basis for understanding cell fate determination and cellular homeostasis in the normal respiratory mucosa at different anatomic sites and show the contribution of different mucosal components to the etiology/molecular pathology of ITAC.

Comprehensive Molecular Characterization of Polymorphous Adenocarcinoma, Cribriform Subtype: Identifying Novel Fusions and Fusion Partners

Polymorphous adenocarcinoma (PAC) is a common, usually low-grade salivary gland carcinoma. While conventional PACs are most associated with PRKD1 p.E710D hotspot mutations, the cribriform subtype is often associated with gene fusions in PRKD1, PRKD2, or PRKD3. These fusions have been primarily identified by fluorescence in situ hybridization (FISH) analysis, with a minority evaluated by next-generation sequencing (NGS). Many of the reported fusions were detected by break-apart FISH probes and therefore have unknown partners or were negative by FISH altogether. In this study, we aimed to further characterize the fusions associated with PAC with NGS. Fifty-four PACs (exclusively cribriform and mixed/intermediate types to enrich the study for fusion-positive cases) were identified and subjected to NGS. Fifty-one cases were successfully sequenced, 28 of which demonstrated gene fusions involving PRKD1, PRKD2, or PRKD3. There were 10 cases with the PRKD1 p.E710D mutation. We identified a diverse group of fusion partners, including 13 novel partners, 3 of which were recurrent. The most common partners for the PRKD genes were ARID1A and ARID1B. The wide variety of involved genes is unlike in other salivary gland malignancies and warrants a broader strategy of sequencing for molecular confirmation for particularly challenging cases, as our NGS study shows.

Diagnostic challenges and prognostic implications of extranodal extension in head and neck cancer: a state of the art review and gap analysis

Extranodal extension (ENE) is a pattern of cancer growth from within the lymph node (LN) outward into perinodal tissues, critically defined by disruption and penetration of the tumor through the entire thickness of the LN capsule. The presence of ENE is often associated with an aggressive cancer phenotype in various malignancies including head and neck squamous cell carcinoma (HNSCC). In HNSCC, ENE is associated with increased risk of distant metastasis and lower rates of locoregional control. ENE detected on histopathology (pathologic ENE; pENE) is now incorporated as a risk-stratification factor in human papillomavirus (HPV)-negative HNSCC in the eighth edition of the American Joint Committee on Cancer (AJCC) and the Union for International Cancer Control (UICC) TNM classification. Although ENE was first described almost a century ago, several issues remain unresolved, including lack of consensus on definitions, terminology, and widely accepted assessment criteria and grading systems for both pENE and ENE detected on radiological imaging (imaging-detected ENE; iENE). Moreover, there is conflicting data on the prognostic significance of iENE and pENE, particularly in the context of HPV-associated HNSCC. Herein, we review the existing literature on ENE in HNSCC, highlighting areas of controversy and identifying critical gaps requiring concerted research efforts.

Pathological Level VI Lymph Node Metastasis in Clinical N3b Pyriform Sinus Squamous Cell Carcinoma

OBJECTIVE

The frequency of metastasis to level VI lymph nodes in advanced pyriform sinus squamous cell carcinoma (PSSCC) is unknown. We intended to analyze the clinical features and pathological presence or absence of level VI lymph node metastasis in patients with PSSCC.

METHODS

The data of 270 patients with previously untreated hypopharyngeal squamous cell carcinoma from 2006 to 2016 were obtained. Patients who underwent pharyngolaryngectomy for the pyriform sinus subsite with a curative intent with level VI dissection were included. We retrospectively analyzed the clinical Tumor-Node (TN) status (TNM classification of malignant tumors, eighth edition) and the presence or absence of pathological level VI lymph node metastasis.

RESULTS

A total of 34 patients were included. Eight patients (24%) had pathological level VI lymph node metastasis. The rate of pathological level VI lymph node metastasis was directly proportional to the clinical N status (P = .0002, Chi-square test for trend). In all, 5 patients with cN2b- 3 were classified as cN3b. Ipsilateral pathological level VI lymph node metastasis was observed in 1 patient, and bilateral metastasis was observed in 3 patients. There was no association between clinical T status or pyriform sinus apex invasion and pathological level VI metastasis (both P > .99, Fisher's exact test).

CONCLUSIONS

PSSCC with cN3b is prone to bilateral level VI metastasis. We recommend that patients with PSSCC with cN3b should undergo bilateral level VI lymph node dissection.

Peripheral Giant Cell Granuloma of the Jaws as First Sign of Primary Hyperparathyroidism: A Case Series

Peripheral giant cell granulomas (PGCG) associated with hyperparathyroidism (HPT) are rare clinical entities. The aim of this study is to report on 21 PGCGs of the oral cavity as the first clinical sign of unknown primary HPT (PHPT) referred to the Complex Operating Unit of Odontostomatology of Aldo Moro University of Bari from 2009 to 2019. Surgical treatment consisted in conservative enucleation of the lesion, if possible, with contextual bone rim osteoplasty with piezosurgical tools and following histological examination. After histological diagnosis of PGCG, PHPT screening was performed dosing parathyroid hormone and serum calcium. In all the patients haematological investigation demonstrated elevated values of parathyroid hormone and serum calcium ruling out an unknown PHPT. Specifically, after endocrinological evaluation, patients showed PHPT related to: parathyroid adenoma (13), parathyroid hyperplasia (two, one of which occurred in a intra-thyroidal parathyroid), and parathyroid carcinoma (1) and were scheduled for surgical treatment. Considering that PGCGs could represent the first clinical sign of an undiagnosed PHPT and the screening of PHPT is a non-invasive and cheap exam, in case of histological diagnosis of a giant cell lesion, both central and peripheral, especially in patients with synchronous or history of methacronous giant cell lesions, parathyroidal screening should be mandatory.

Application of the Milan System for Reporting Salivary Gland Cytopathology to cystic salivary gland lesions

BACKGROUND

Cystic salivary gland lesions present diagnostic challenges on fine-needle aspiration (FNA) specimens that are related to sampling limitations and a broad differential diagnosis. This study evaluated the benefit of applying the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) to a series of cystic salivary gland lesions.

METHODS

The pathology archives at the Johns Hopkins Hospital were searched to identify cystic salivary gland FNA specimens over a 19-year period (2000-2018). Patient demographics, cytomorphologic features, and clinical and surgical follow-up were recorded. The MSRSGC was applied to the cases. The risk of malignancy (ROM) and the risk of neoplasia (RON) were calculated for each category.

RESULTS

One hundred seventy-eight cases were identified (96 males and 82 females) with a mean age of 53 years (range, 4-90 years). After the MSRSGC was applied, there were 52 nondiagnostic cases (29.2%), 80 nonneoplastic cases (44.9%), 35 cases of atypia of undetermined significance (AUS; 19.7%), 3 benign neoplasms (1.7%), 3 salivary gland neoplasms of uncertain malignant potential (SUMP; 1.7%), 4 cases suspicious for malignancy (SFM; 2.2%), and 1 malignant case (0.6%). One hundred fifty-six of the 178 patients (87.6%) had follow-up data available. The RON and ROM values for cases with surgical follow-up were 33.3% (3 of 9) and 22.2% (2 of 9) for the nondiagnostic category, 42.9% (9 of 21) and 19% (4 of 21) for the nonneoplastic category, 76.5% (13 of 17) and 29.4% (5 of 17) for the AUS category, 100.0% (2 of 2) and 50.0% (1 of 2) for the SUMP category, and 100% (2 of 2) and 100% (2 of 2) for the SFM category, respectively.

CONCLUSIONS

Applying the MSRSGC to cystic salivary gland lesions improves patient management by preventing unnecessary surgery for nonneoplastic conditions. The ROM was highest in the SFM category (100%), which was followed by the SUMP, AUS, nondiagnostic, and nonneoplastic categories. Less than adequate specimens may increase the diagnosis of AUS.

Assessing the diagnostic accuracy for pleomorphic adenoma and Warthin tumor by employing the Milan System for Reporting Salivary Gland Cytopathology: An international, multi-institutional study

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has established distinct diagnostic categories for reporting cytopathological findings, and each is associated with a defined risk of malignancy (ROM). However, the ROM is applied at the overall category level and is not specific for particular morphological entities within a category. Here, the diagnostic performance of the MSRSGC for pleomorphic adenoma (PA) and Warthin tumor (WT) is reported.

METHODS

The pathology archives of 11 institutions from 4 countries were retrospectively searched to identify all salivary gland fine-needle aspiration (FNA) biopsies with a differential or definitive diagnosis of PA or WT and all resection specimens with a diagnosis of PA or WT; only paired cases were included. All FNA diagnoses were retrospectively classified according to the MSRSGC.

RESULTS

A total of 1250 cases met the inclusion criteria, and they included 898 PA cases and 352 WT cases. The ROM in the benign neoplasm category was 3.0% and 1.3% for cases with a differential or definitive diagnosis of PA and WT, respectively. The ROM in the salivary gland neoplasm with uncertain malignant potential (SUMP) category was 2.7% and 18.8% for PA and WT, respectively (P = .0277). The diagnostic accuracy for PA and WT was 95.1% and 96.1%, respectively.

CONCLUSIONS

The diagnostic accuracy for PA and WT on FNA is high. Furthermore, these findings highlight the difference in the ROMs associated with 2 specific differential diagnoses in the SUMP category: basaloid neoplasms and oncocytoid neoplasms.

Quality Assessment Across Disciplines in Head and Neck Cancer Treatment Diagnostic Pathology in HNSCC

Quality assured pathology services are integral to provision of optimal management for patients with head and neck cancer. Pathology services vary globally and are dependent on resources in terms of both laboratory provision and availability of a highly trained and accredited workforce. Ensuring a high-quality pathology service depends largely on close working and effective communication between the clinical team providing treatment and the pathologists providing laboratory input. Laboratory services should be quality assured by achieving external accreditation, most often by conforming to International Organization for Standardization (ISO) standards such as ISO15189 sometimes with ISO17025 or alternatively ISO17020. Quality of diagnostic reporting can be assured by the ISO but clinical teams should endeavor to work with pathologists who engage in continuing professional development, external quality assurance and audit. Research also contributes to diagnostic reporting quality. A number of initiatives in the UK such as the EPSRC/MRC funded Molecular Pathology Nodes and the National Cancer Research Institute Cellular-Molecular Pathology initiative (C-M Path), for example, have linked pathologists, industry and researchers. This has resulted in centers leading in digital innovation, artificial intelligence, translational research and clinical trials supported by pathologists. For rare tumors and contemporary molecular diagnostics, biopsy material can increasingly be shared with expert specialist pathologists working in specialist centers, particularly by using digital pathology platforms with potentially global reach. High quality services for the majority of diagnostic processes required for head and neck cancer management is best provided by local pathologists where communication with the treating team is more effective than with pathologists working in remote centers. Quality assurance is an increasingly important aspect of pathology, assuring not only effective turnaround times and accuracy for the diagnostic service but also high quality consistent reporting for clinical trials where even small pathology errors can potentially produce a significant bias and in the worst case negate the value of a completed trial. Better outcomes have been associated with centers engaged in clinical trials than in non-participating centers. Provision of a quality assured pathology service should extend to both the research and diagnostic services.

Squamous Cell and Adenoid Cystic Carcinoma Collision Tumor of the Soft Palate Treated with Surface Mold Brachytherapy

Simultaneous primary cancers are rare in the oropharynx. This report describes the first reported case of a collision tumor of squamous cell and adenoid cystic carcinoma in the soft palate. The patient was immunosuppressed with a history of liver transplantation, smoking and heavy alcohol drinking. He was treated with wide local excision followed by adjuvant radiotherapy with surface acrylic mold brachytherapy. This technique was used instead of external beam radiotherapy in order to minimize toxicity. The patient tolerated the treatment well and with the only acute grade two mucositis at the soft palate and minimal late toxicity. There is no evidence of disease recurrence and the patient continues to maintain excellent quality of speech and swallowing 14 months after treatment completion.

Utility of 3-Month Surveillance F-18 FDG PET/CT in Surgically Resected Oral Squamous Cell Carcinoma

OBJECTIVES

To evaluate the performance of surveillance F-18 fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) 1 year after imaging in oral squamous cell carcinoma (OSCC) patients treated with definitive surgery and adjuvant (chemo)radiotherapy (RT).

METHODS AND MATERIALS

Surveillance PET/CT accuracy was retrospectively evaluated in OSCC patients receiving surgical resection and (chemo)RT. Pathologic risk factors were assessed for influence on accuracy of the post-RT PET/CT.

RESULTS

Fifty-four patients with median follow-up of 3.8 years met inclusion criteria. A PET/CT obtained a median of 3.4 months after RT revealed 11 (20.4%) instances of true disease recurrence: 4 locoregional alone, 6 distant alone, and 1 patient with locoregional and distant disease. Locoregional detection sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 55.6%, 75.0%, 33.3%, and 88.2%, respectively. For distant recurrence, the respective values were 100%, 95.2%, 77.8%, and 100%. Absence of bone invasion, absence of pT4 disease, and disease within the tongue were independently associated with higher sensitivity ( P = .048). Perineural invasion was associated with increased specificity ( P = .027), and tumor location in the tongue was associated with a higher PPV ( P = .007) on surveillance PET/CT.

CONCLUSIONS

Post-RT PET/CT accuracy information for surgically managed OSCC patients demonstrates significant associations with pathologic factors.

Enhancing airway assessment of patients with head and neck pathology using virtual endoscopy

Studies have demonstrated that poor assessment and planning contribute to airway complications and that current airway assessment strategies have a poor diagnostic accuracy in predicting difficult intubation in the general population. Patients with head and neck pathology are at higher risk for difficulties during airway management and are more likely to need emergency surgical access. Therefore, thorough assessment of this group of patients is mandatory. The addition of virtual endoscopy (VE) to clinical history and computerised tomography imaging has been shown to improve diagnostic accuracy for supraglottic, glottic and infraglottic lesions and has a positive influence in formulating a more cautious and thorough airway management strategy in this high-risk group of patients. This article reviews whether VE can enhance airway assessment in patients with head and neck pathology and help reduce airway complications.

Cystic major salivary gland lesions: Utilizing fine needle aspiration to optimize the clinical management of a broad and diverse differential diagnosis

INTRODUCTION

The use of fine-needle aspiration (FNA) cytology for the preoperative evaluation of salivary gland lesions is an accepted but, currently, nonstandardized practice. More specifically, cystic major salivary gland lesions are relatively rare and can be very challenging to diagnose on FNA due to low cellularity and an incredibly broad differential diagnosis. The purpose of this study was to investigate the diagnostic utility of preoperative FNA cytology for cystic major salivary gland lesions.

METHODS AND MATERIALS

The electronic pathology archives of The Johns Hopkins Hospital were searched to identify FNA specimens of cystic major salivary gland lesions over a 15 year period (January 1, 2000 to December 21, 2015). The age, race, sex, biopsy site, use of ultrasound guidance, cytopathologic diagnosis, and presence or absence of clinical follow-up were recorded for each patient. Cases were divided into those with and without follow-up. Diagnostic performance between FNA and follow-up data were recorded.

RESULTS

A total of 145 cases met the inclusion criteria, while 123 (84.8%) patients had follow-up data available. Of these patients, 67.5% underwent FNA as the only pathologic diagnostic modality. Sensitivity, specificity, positive predictive value, and negative predictive value for the detection of cystic neoplasms were 41.6%, 99.0%, 90.9%, and 87.6%, respectively. For cases containing mucin, 100.0% sensitivity and specificity were achieved.

CONCLUSION

FNA of cystic salivary gland lesions is a useful clinical decision-making tool that can reduce the number of patients ultimately requiring surgical excision. Although specificity is high, a relatively low overall sensitivity makes clinical and radiologic correlation imperative.

Sialolithiasis in an Accessory Submandibular Gland Identified by Magnetic Resonance Sialography

BACKGROUND

Accessory submandibular gland is a very rare anatomical variant. There have been only 6 reported cases of this entity in the English literature, only 1 of which was identified using magnetic resonance imaging.

METHODS

We report the case of a 39-year-old female with symptoms of left submandibular sialoadenitis who was diagnosed of sialolithiasis within the left accessory submandibular gland by magnetic resonance sialography (MR-Si).

RESULTS

The calculus was palpated near the submandibular papilla and was extracted by an intraoral approach. One-year follow-up revealed no evidence of recurrence.

CONCLUSIONS

This is the first case reported to date in the English literature of a patient with sialolithiasis within an accessory submandibular gland diagnosed by MR-Si.

Unresectable Extraskeletal Myxoid Chondrosarcoma of the Neck: Early Tumor Response to Chemoradiotherapy

Extraskeletal myxoid chondrosarcoma (EMC) rarely occurs in the head and neck and is generally managed with primary surgery. To our knowledge, no cases of unresectable EMC of the neck have been reported. We present a case of an unresectable EMC treated with chemotherapy and radiation, and highlight the exceptional early response to therapy. 

Microscopic thymoma and parathyroid adenoma: rare combination of two distinct pathologies

While there is an intimate anatomical and embryological relationship between the inferior parathyroid gland and thymus, concurrent pathology is rare. Three cases have been reported in the literature of a parathyroid adenoma in conjunction with a thymoma. We present a case report of a 60-year-old female with a past medical history of hypercalcemia subsequently found to have primary hyperparathyroidism. Sestamibi scan of the parathyroid revealed increased uptake in the lower left neck consistent with a parathyroid adenoma. A standard transverse neck incision was performed with exploration of the lower left thyroid pole. Further dissection was required to identify the parathyroid gland which was intimately associated with thymic tissue in the superior mediastinum. Both thymic tissue and the parathyroid gland were sent for pathology. Permanent pathology subsequently revealed a parathyroid adenoma with an incidental spindle cell thymoma. The embryological relationship of the inferior parathyroid glands and the thymus is well known as both are derived from the third branchial pouch. However, there are only 3 other previous reports of parathyroid adenoma associated with a thymoma in the current literature. Interestingly, up to 16% of parathyroid adenomas are found in the mediastinum, and the current literature states the incidence of thymoma varies from 10-42%.

Dr. Andrew Huvos (1934-2006) retrospective: a tribute to the pathologist and the man

Andrew G. Huvos was born in communist Budapest, Hungary, in March of 1934. At twenty-four he immigrated to New York City, working as a cytotechnologist at Delafield Hospital. Dr. Huvos attended the University of Gottingen Medical School in Germany, where he was awarded his MD degree. He completed a 1-year internship at New York Hospital, going on to Residency at Delafield Hospital and Fellowship at Presbyterian Hospital. Dr. Huvos ascended through the ranks to Attending Pathologist and Member at Memorial Hospital for Cancer and Allied diseases, at Memorial Sloan-Kettering Cancer Center (MSKCC) in New York City. Concurrently, he was appointed to Weill Medical College of Cornell University, where he was Professor of Pathology for over two decades. Dr. Huvos was an editorial referee for over half a dozen highly esteemed publications, including the New England Journal of Medicine and Cancer. He trained over a thousand oncological surgical pathology fellows, head and neck fellows, and surgeons. Dr. Huvos spent nearly 40 years at MSKCC and his career was accompanied by his authorship of 388 peer-reviewed publications and eighteen book chapters. His legacy leaves behind a generation of pathologists who have greatly benefited from his tutelage.

The spectrum of gnathic osteosarcoma: caveats for the clinician and the pathologist

Seven expansile jaw lesions in patients ranging from 7 to 63 years are presented to illustrate diagnostic and management issues pertaining to cases ultimately proven to be gnathic osteosarcoma (GO). Six of the cases in our series were low-grade osteoblastic and one high-grade chondroblastic. None of our cases exhibited the characteristic "sunburst" radiopaque appearance described for GO. All of our cases displayed cortical expansion and one showed development of diastema. Two occurred in the maxilla and five in the mandible. Two of the patients with mandibular lesions presented initially with pain; all other patients were asymptomatic. Lack of pain resulted in a delay in diagnosis due to postponement of consultation or biopsy. Two cases underwent initial shallow non-representative biopsies, requiring a second biopsy for definitive diagnosis, further delaying treatment. Those biopsies were initially interpreted as pyogenic granuloma and peripheral ossifying fibroma, respectively. GO should always be considered in the differential diagnosis of expansile jaw lesions. Bone biopsies of lesions exhibiting pain and expansion of cortical plates should include medullary bone in order to minimize sampling error. In addition, all rapidly growing or painful exophytic bone lesions, and presumed soft tissue lesions that may involve underlying bone, should be examined histopathologically, and receive clinical and radiographic follow-up until complete resolution or healing is evident, regardless of the diagnosis. Based on the positive outcomes of the patients in our series, the prognosis of GO appears to be relatively favorable when compared to other sarcomas and osteosarcomas of long bones.

Hereditary paraganglioma of the nasopharynx

Head and neck paragangliomas are rare neuroendocrine tumors derived from neural crest cells of parasympathetic ganglia or the widely dispersed neuroendocrine cells of the head and neck region. Paragangliomas of the sinonasal tract and nasopharynx are rare. The clinicopathologic features of this unique example of a hereditary, nasopharyngeal paraganglioma, and selective entities that are included in its differential diagnosis are presented.