Analysis of cytogenetic aberrations in esthesioneuroblastomas by comparative genomic hybridization

Olfactory neuroblastoma mimics molecular heterogeneity and lineage trajectories of small-cell lung cancer

The olfactory epithelium undergoes neuronal regeneration from basal stem cells and is susceptible to olfactory neuroblastoma (ONB), a rare tumor of unclear origins. Employing alterations in Rb1/Trp53/Myc (RPM), we establish a genetically engineered mouse model of high-grade metastatic ONB exhibiting a NEUROD1+ immature neuronal phenotype. We demonstrate that globose basal cells (GBCs) are a permissive cell of origin for ONB and that ONBs exhibit cell fate heterogeneity that mimics normal GBC developmental trajectories. ASCL1 loss in RPM ONB leads to emergence of non-neuronal histopathologies, including a POU2F3+ microvillar-like state. Similar to small-cell lung cancer (SCLC), mouse and human ONBs exhibit mutually exclusive NEUROD1 and POU2F3-like states, an immune-cold tumor microenvironment, intratumoral cell fate heterogeneity comprising neuronal and non-neuronal lineages, and cell fate plasticity-evidenced by barcode-based lineage tracing and single-cell transcriptomics. Collectively, our findings highlight conserved similarities between ONB and neuroendocrine tumors with significant implications for ONB classification and treatment.

Update on olfactory neuroblastoma

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

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

The genomics and epigenetics of olfactory neuroblastoma: A systematic review

BACKGROUND

Olfactory neuroblastoma (ONB) or esthesioneuroblastoma (ENB) is a rare malignancy of the nasal cavity believed to arise from the olfactory epithelium. The goal of this study was to systematically review the genomics, epigenetics, and cytogenetics of ONB and to understand the potential clinical implications of these studies.

METHODS

A systematic literature review was performed for articles published before May 2020 using Cochrane, Embase, Pubmed, and Scopus databases. Inclusion criteria included genomics, cytogenetics, and epigenetics studies on ONB. Exclusion criteria included studies not in English or systematic reviews. Articles and abstracts were reviewed by two independent reviewers to reduce bias during article selection and synthesis of results. Of the 36 studies included in this review, 24 were research articles and 12 were abstracts.

RESULTS

Although recurrent mutations among ONB tumors are uncommon, alterations in TP53, DMD, PIK3CA, NF1, CDKN2A, CDKN2C, CTNNB1, EGFR, APC, cKIT, cMET, PDGFRA, CDH1, FH, SMAD4, FGFR3 and IDH2 genes have been reported in several recent studies. In addition, cytogenetic studies revealed that the landscape of chromosomal aberrations varies widely amongst ONB tumors.

CONCLUSIONS

The rare character of ONB has limited the sample size available for cytogenetic, genomic, and epigenetic studies and contributes to the limitations of this systematic review. Comprehensive genomic and epigenomic studies with larger cohorts are warranted to validate the initial reports summarized in this review and to identify potential therapeutic targets for ONB.

Translational genomics of sinonasal cancers

The sinonasal cavities harbor a wide variety of histologically distinct cancers, the majority very aggressive with 5-year survival rates between 30-60% and local recurrence as the main cause of death. This is a complex anatomic area, close to structures such the eyes and the brain, which is of special relevance for surgery and postoperative radiotherapy. The low incidence of these rare tumors hampers accumulation of experience with diagnosis and clinical managment as well as knowledge on recurrent genetic aberrations or testing of new treatment strategies. However, recent years have seen a growing number of publications on genetic aberrations providing data that can aid or fine-tune classification and provide molecular targets for treatment with specific inhibitors. In addition, new sinonasal cancer models are created that enable preclinical testing of candidate inhibitor drugs. With more and more novel targeted therapies being developed, options for personalized treatment of sinonasal cancer patients are now opening up.

Central neurocytoma: SNP array analyses, subtel FISH, and review of the literature

The central neurocytoma (CN) is a rare brain tumor with a frequency of 0.1-0.5% of all brain tumors. According to the World Health Organization classification, it is a benign grade II tumor with good prognosis. However, some CN occur as histologically "atypical" variant, combined with increasing proliferation and poor clinical outcome. Detailed genetic knowledge could be helpful to characterize a potential atypical behavior in CN. Only few publications on genetics of CN exist in the literature. Therefore, we performed cytogenetic analysis of an intraventricular neurocytoma WHO grade II in a 39-year-old male patient by use of genome-wide high-density single nucleotide polymorphism array (SNP array) and subtelomere FISH. Applying these techniques, we could detect known chromosomal aberrations and identified six not previously described chromosomal aberrations, gains of 1p36.33-p36.31, 2q37.1-q37.3, 6q27, 12p13.33-p13.31, 20q13.31-q13.33, and loss of 19p13.3-p12. Our case report contributes to the genetic knowledge about CN and to increased understanding of "typical" and "atypical" variants.

Genomic analysis identifies frequent deletions of Dystrophin in olfactory neuroblastoma

Olfactory neuroblastoma (ONB) is a rare malignant neoplasm arising in the upper portion of the sinonasal cavity. To better understand the genetic bases for ONB, here we perform whole exome and whole genome sequencing as well as single nucleotide polymorphism array analyses in a series of ONB patient samples. Deletions involving the dystrophin (DMD) locus are found in 12 of 14 (86%) tumors. Interestingly, one of the remaining tumors has a deletion in LAMA2, bringing the number of ONBs with deletions of genes involved in the development of muscular dystrophies to 13 or 93%. This high prevalence implicates an unexpected functional role for genes causing hereditary muscular dystrophies in ONB.

DNA methylation-based reclassification of olfactory neuroblastoma

Olfactory neuroblastoma/esthesioneuroblastoma (ONB) is an uncommon neuroectodermal neoplasm thought to arise from the olfactory epithelium. Little is known about its molecular pathogenesis. For this study, a retrospective cohort of n = 66 tumor samples with the institutional diagnosis of ONB was analyzed by immunohistochemistry, genome-wide DNA methylation profiling, copy number analysis, and in a subset, next-generation panel sequencing of 560 tumor-associated genes. DNA methylation profiles were compared to those of relevant differential diagnoses of ONB. Unsupervised hierarchical clustering analysis of DNA methylation data revealed four subgroups among institutionally diagnosed ONB. The largest group (n = 42, 64%, Core ONB) presented with classical ONB histology and no overlap with other classes upon methylation profiling-based t-distributed stochastic neighbor embedding (t-SNE) analysis. A second DNA methylation group (n = 7, 11%) with CpG island methylator phenotype (CIMP) consisted of cases with strong expression of cytokeratin, no or scarce chromogranin A expression and IDH2 hotspot mutation in all cases. T-SNE analysis clustered these cases together with sinonasal carcinoma with IDH2 mutation. Four cases (6%) formed a small group characterized by an overall high level of DNA methylation, but without CIMP. The fourth group consisted of 13 cases that had heterogeneous DNA methylation profiles and strong cytokeratin expression in most cases. In t-SNE analysis, these cases mostly grouped among sinonasal adenocarcinoma, squamous cell carcinoma, and undifferentiated carcinoma. Copy number analysis indicated highly recurrent chromosomal changes among Core ONB with a high frequency of combined loss of chromosome 1-4, 8-10, and 12. NGS sequencing did not reveal highly recurrent mutations in ONB, with the only recurrently mutated genes being TP53 and DNMT3A. In conclusion, we demonstrate that institutionally diagnosed ONB are a heterogeneous group of tumors. Expression of cytokeratin, chromogranin A, the mutational status of IDH2 as well as DNA methylation patterns may greatly aid in the precise classification of ONB.

Sinonasal Neuroendocrine Neoplasms: Current Challenges and Advances in Diagnosis and Treatment, with a Focus on Olfactory Neuroblastoma

Sinonasal tumors with neuroendocrine differentiation form a group of rare heterogeneous neoplasms of neuroectodermal and epithelial origin, consisting of olfactory neuroblastomas and neuroendocrine carcinomas. Because the natural history and biological behavior of this group of tumors vary, the morphological diagnosis coupled with grading/staging is important for prognostication, and the approach to treatment and rehabilitation is multidisciplinary. The identification of molecular abnormalities underlying these tumors is critical to the development of specific targeted therapies and the design of clinical trials.

Genetic and molecular alterations in olfactory neuroblastoma: implications for pathogenesis, prognosis and treatment

Olfactory neuroblastoma (ONB, Esthesioneuroblastoma) is an infrequent neoplasm of the head and neck area derived from olfactory neuroepithelium. Despite relatively good prognosis a subset of patients shows recurrence, progression and/or metastatic disease, which requires additional treatment. However, neither prognostic nor predictive factors are well specified. Thus, we performed a literature search for the currently available data on disturbances in molecular pathways, cytogenetic changes and results gained by next generation sequencing (NGS) approaches in ONB in order to gain an overview of genetic alterations which might be useful for treating patients with ONB. We present briefly ONB molecular pathogenesis and propose potential therapeutic targets and prognostic factors. Possible therapeutic targets in ONB include: receptor tyrosine kinases (c-kit, PDGFR-b, TrkB; EGFR); somatostatin receptor; FGF-FGFR1 signaling; Sonic hedgehog pathway; apoptosis-related pathways (Bcl-2, TRAIL) and neoangiogenesis (VEGF; KDR). Furthermore, we compare high- and low-grade ONB, and describe its frequent mimicker: sinonasal neuroendocrine carcinoma. ONB is often a therapeutic challenge, so our goal should be the implementation of acquired knowledge into clinical practice, especially at pretreated, recurrent and metastatic stages. Moreover, the multicenter molecular studies are needed to increase the amount of available data.

Comprehensive Molecular Profiling of Olfactory Neuroblastoma Identifies Potentially Targetable FGFR3 Amplifications

Olfactory neuroblastomas (ONBs), also known as esthesioneuroblastomas, are malignant round-cell tumors that represent up to 5% of sinonasal malignancies. Despite their aggressive course, molecular studies of ONBs have been limited, and targeted therapies are lacking. To identify potential oncogenic drivers and targetable pathways in ONBs, we characterized 20 ONBs, including archived ONBs profiled by targeted, multiplexed PCR (mxPCR)-based DNA next-generation sequencing (NGS) of the coding sequence of over 400 cancer-relevant genes (n = 16), mxPCR-based RNA NGS of 108 target genes (n = 15), and 2 ONBs profiled by comprehensive hybrid-capture-based clinical grade NGS of >1,500 genes. Somatic mutations were infrequent in our cohort, with 7 prioritized nonsynonymous mutations in 5 of 18 (28%) ONBs, and no genes were recurrently mutated. We detected arm/chromosome-level copy-number alterations in all tumors, most frequently gains involving all or part of chromosome 20, chromosome 5, and chromosome 11. Recurrent focal amplifications, often but not exclusively in the context of arm-level gains, included CCND1 [n = 4/18 (22%) tumors] and the targetable receptor tyrosine kinase FGFR3 [n = 5/18 (28%) tumors]. Targeted RNA NGS confirmed high expression of FGFR3 in ONB (at levels equivalent to bladder cancer), with the highest expression observed in FGFR3-amplified ONB cases. Importantly, our findings suggest that FGFR3 may be a therapeutic target in a subset of these aggressive tumors.Implications: ONBs harbor recurrent chromosomal copy-number changes, including FGFR3 amplification associated with overexpression. Hence, FGFR3 may represent a novel therapeutic target in these tumors. Mol Cancer Res; 15(11); 1551-7. ©2017 AACR.

Comprehensive Genomic Profiling of Esthesioneuroblastoma Reveals Additional Treatment Options

BACKGROUND

Esthesioneuroblastoma (ENB), also known as olfactory neuroblastoma, is a rare malignant neoplasm of the olfactory mucosa. Despite surgical resection combined with radiotherapy and adjuvant chemotherapy, ENB often relapses with rapid progression. Current multimodality, nontargeted therapy for relapsed ENB is of limited clinical benefit.

MATERIALS AND METHODS

We queried whether comprehensive genomic profiling (CGP) of relapsed or refractory ENB can uncover genomic alterations (GA) that could identify potential targeted therapies for these patients. CGP was performed on formalin-fixed, paraffin-embedded sections from 41 consecutive clinical cases of ENBs using a hybrid-capture, adaptor ligation based next-generation sequencing assay to a mean coverage depth of 593X. The results were analyzed for base substitutions, insertions and deletions, select rearrangements, and copy number changes (amplifications and homozygous deletions).

RESULTS

Clinically relevant GA (CRGA) were defined as GA linked to drugs on the market or under evaluation in clinical trials. A total of 28 ENBs harbored GA, with a mean of 1.5 GA per sample. Approximately half of the ENBs (21, 51%) featured at least one CRGA, with an average of 1 CRGA per sample. The most commonly altered gene was TP53 (17%), with GA in PIK3CA, NF1, CDKN2A, and CDKN2C occurring in 7% of samples.

CONCLUSION

We report comprehensive genomic profiles for 41 ENB tumors. CGP revealed potential new therapeutic targets, including targetable GA in the mTOR, CDK and growth factor signaling pathways, highlighting the clinical value of genomic profiling in ENB.

IMPLICATIONS FOR PRACTICE

Comprehensive genomic profiling of 41 relapsed or refractory ENBs reveals recurrent alterations or classes of mutation, including amplification of tyrosine kinases encoded on chromosome 5q and mutations affecting genes in the mTOR/PI3K pathway. Approximately half of the ENBs (21, 51%) featured at least one clinically relevant genomic alteration (CRGA), with an average of 1 CRGA per sample. The most commonly altered gene was TP53 (17%), and alterations in PIK3CA, NF1, CDKN2A, or CDKN2C were identified in 7% of samples. Responses to treatment with the kinase inhibitors sunitinib, everolimus, and pazopanib are presented in conjunction with tumor genomics.

Comparative genomic hybridization on microarray (a-CGH) in olfactory neuroblastoma: Analysis of ten cases and review of the literature

Olfactory neuroblastoma is a rare tumor arising from the basal layer of the olfactory epithelium in the superior recesses of the nasal cavity. The rarity of this tumor, and the difficulties in culturing tumor cells has limited the generation of conventional cytogenetic data, whereas consistent results have been obtained by recent molecular methods. We report the results of an array-based comparative genomic hybridization analysis (a-CGH) obtained on 11 samples from 10 subjects: 8 primary and 3 relapsed tumors. In one patient, both the primary and relapsed tumors were available. Our results on chromosome imbalances highlight the highly heterogeneous presentation: six of eleven samples showed multiple numerical changes and very few structural ones, while four samples showed an opposite pattern; one sample out of eleven showed no imbalances. We did not reach firm evidence of any recurrent specific imbalances either at level of entire chromosomes or chromosome segments. A review of the literature indicates a number of recurrent gains, and losses, mostly not confirmed by our results. Gain of chromosome 19 was the only correspondence with literature data concerning an entire chromosome, and most segmental gains and losses found in our cohort of patients were different from those indicated in the literature: the only similarities concerned the gain of 20q13 and the loss of segments of chromosomes 15 and 22.

Esthesioneuroblastoma, neuroendocrine carcinoma, and sinonasal undifferentiated carcinoma: differentiation in diagnosis and treatment

Introduction Malignant sinonasal tumors comprise less than 1% of all neoplasms. A wide variety of tumors occurring primarily in this site can present with an undifferentiated or poorly differentiated morphology. Among them are esthesioneuroblastomas, sinonasal undifferentiated carcinomas, and neuroendocrine carcinomas. Objectives We will discuss diagnostic strategies, recent advances in immunohistochemistry and molecular diagnosis, and treatment strategies. Data Synthesis These lesions are diagnostically challenging, and up to 30% of sinonasal malignancies referred to the University of Texas MD Anderson Cancer Center are given a different diagnosis on review of pathology. Correct classification is vital, as these tumors are significantly different in biological behavior and response to treatment. The past decade has witnessed advances in diagnosis and therapeutic modalities leading to improvements in survival. However, the optimal treatment for esthesioneuroblastoma, sinonasal undifferentiated carcinoma, and neuroendocrine carcinoma remain debated. We discuss advances in immunohistochemistry and molecular diagnosis, diagnostic strategies, and treatment selection. Conclusions There are significant differences in prognosis and treatment for esthesioneuroblastoma, neuroendocrine carcinoma, and sinonasal undifferentiated carcinoma. Recent advances have the potential to improve oncologic outcomes but further investigation in needed.

[Esthesioneuroblastoma]

Esthesioneuroblastoma is an uncommon malignancy originating from olfactive epithelium. Men are more frequently affected than women. Nasal symptoms are the most common revealing signs. Immunohistochemistry helps diagnosis. There is no randomized trial evaluating treatment due to the low incidence of this tumor. Radiotherapy and surgery are the standard of care. Radiotherapy is benefic even in early stage disease. Chemotherapy is indicated in case of locally advanced or metastatic disease.

Clonal trisomy 4 cells detected in the ossifying renal tumor of infancy: study of 3 cases

The ossifying renal tumor of infancy is a rare neoplasm diagnosed in the first 2 years of life, predominantly in boys. The neoplasm is primarily characterized by the presence of a large ossifying component. Its most common mode of presentation is hematuria, and it has a uniformly benign behavior. The karyotypic makeup of the process has not been reported. Thus, a study was undertaken and it allowed demonstration of clonal trisomy 4, which was confirmed by the fluorescent in-situ hybridization-probing of two additional archival formalin-fixed, paraffin-imbedded similar tumors. On the basis of the findings in these three cases, it seems that clonal trisomy 4 may be considered as a characteristic of the tumor, which makes it distinct from any other infantile renal tumor.

[Diagnostic difficulties of the patient with sinonasal tract tumor; therapeutic dilemmas - a case report and up to date review]

Esthesioneuroblastoma (ENB) is a rare malignancy unique to the sinonasal tract. It arises from the olfactory epithelium and has a tendency to originate from one side of the nasal cavity and paranasal sinuses with frequent extension into the cranial cavity and orbit. There is a bimodal age distribution between 11 and 20 years and between 51 and 60 years. ENB accounts for approximately 2-3% of intranasal cancers. Due to the non-specific nature of the initial presentation and slow growth of the tumor, patients often have a long history before diagnosis. Physicians including pathologists are not always aware of distinctive features of ENB especially radiographic, histologic and immunohistochemical characteristics. Additional difficulty can be the fact that Esthesioneuroblastoma can histologically mimic many tumors within the sinonasal tract. We report on a 38-year-old male patient with a Kadish stage C tumor with frontal lobe invasion. The patient underwent a craniofacial resection with a combined head neck and neurosurgeon team. After the surgery postoperative radiotherapy was used. The aim of this study is to present the natural history of the malignancy, the diagnostic process, treatment and prognosis, based on the literature review.

Olfactory neuroblastoma: a review and update

Olfactory neuroblastoma (ONB) is a malignant neuroectodermal tumor that typically occurs in the superior nasal cavity. It is a distinct entity with features that include nesting, low-grade stippled nuclei, and neurofibrillary stroma with formation of pseudorosettes. It has a distinctive immunoprofile that includes keratin negativity, neuroendocrine marker positivity, and S100 positive sustentacular cells, which surround the nests of tumor in a supportive manner. Although the typical clinicopathologic features leave little room for misinterpretation, the wide variability in this tumor may cause diagnostic difficulty. This includes immunophenotypic diversity or patchy staining with immunomarkers, wide spectrum of grade and histology, posttreatment changes, and occasional divergent differentiation. In addition, problems in sampling, preservation, and clinical localization may make the diagnosis more challenging. A large group of tumors may show morphologic overlap with ONB, with some mimicking low-grade tumors, whereas others mimic high-grade tumors. This differential diagnosis has important treatment and prognostic implications. Further complicating the issue is that many of the mimics themselves may show great morphologic and immunophenotypic variability. This manuscript will review the typical clinical and pathologic features of ONB, address the great variability of ONB in our experience, will focus on the differential diagnosis and report on recent findings in these tumors including molecular genetics where applicable.

Olfactory neuroblastoma

Few neoplasms are unique to the sinonasal tract, but sinonasal undifferentiated carcinoma and olfactory neuroblastoma are malignant tumors which require unique management. Due to the rarity of these tumors, practicing pathologists are not always aware of their distinctive clinical, radiographic, histologic, immunohistochemical, and molecular features. These cases are frequently submitted for consultation, further suggesting the diagnostic difficulties inherent to these tumors. Specifically, olfactory neuroblastoma is a neoplasm that can histologically mimic many tumors within the sinonasal tract, making recognition of this tumor important, as the management frequently requires a bicranial-facial surgical approach, a trephination procedure which can be quite technically difficult and challenging to achieve a good result. The management is therefore quite unique in comparison to other sinonasal tract malignancies, setting it apart diagnostically and managerially from other lesions.

Array comparative genomic hybridization analysis of olfactory neuroblastoma

Olfactory neuroblastoma is an unusual neuroectodermal malignancy, which is thought to arise at the olfactory membrane of the sinonasal tract. Due to its rarity, little is understood regarding its molecular and cytogenetic abnormalities. The aim of the current study is to identify specific DNA copy number changes in olfactory neuroblastoma. Thirteen dissected tissue samples were analyzed using array comparative genomic hybridization. Our results show that gene copy number profiles of olfactory neuroblastoma samples are complex. The most frequent changes included gains at 7q11.22-q21.11, 9p13.3, 13q, 20p/q, and Xp/q, and losses at 2q31.1, 2q33.3, 2q37.1, 6q16.3, 6q21.33, 6q22.1, 22q11.23, 22q12.1, and Xp/q. Gains were more frequent than losses, and high-stage tumors showed more alterations than low-stage olfactory neuroblastoma. Frequent changes in high-stage tumors were gains at 13q14.2-q14.3, 13q31.1, and 20q11.21-q11.23, and loss of Xp21.1 (in 66% of cases). Gains at 5q35, 13q, and 20q, and losses at 2q31.1, 2q33.3, and 6q16-q22, were present in 50% of cases. The identified regions of gene copy number change have been implicated in a variety of tumors, especially carcinomas. In addition, our results indicate that gains in 20q and 13q may be important in the progression of this cancer, and that these regions possibly harbor genes with functional relevance in olfactory neuroblastoma.

Comprehensive cytogenetic characterization of an esthesioneuroblastoma

Esthesioneuroblastoma is a malignant neuroectodermal tumor originating from olfactory epithelial cells in the nasal vault. Due to the rarity of this tumor entity, cytogenetic data are very limited. Therefore, we performed comprehensive cytogenetic analyses of an esthesioneuroblastoma, Hyam's grade III-IV, using trypsin-Giemsa staining (GTG banding), multicolor fluorescence in situ hybridization (M-FISH), and locus-specific FISH complemented by molecular karyotyping using high-density single nucleotide polymorphism arrays. GTG banding of 25 metaphases revealed 54 structural intrachromosomal aberrations, predominantly located on 2q, 6q, 21q, and 22q, which were confirmed by FISH analysis. Interestingly, we found two novel, so far not described deletions, del(2)(q37) and del(21)(q22). Using GTG banding, locus-specific FISH, and M-FISH, we detected numeric changes of chromosomes 5, 17, 19, and 22, as well as trisomy 8 at low frequency. Applying SNP array karyotyping, we confirmed the chromosomal aberrations del(2)(q37.3), del(3)(q27.2), del(10)(q26.11), chromosomal imbalance on 17q, del(21)(q22), and revealed a number of so far unknown aberrations (gain of 2q14.3, 13q33.3, and 13q34). While the cytogenetically revealed low frequency mosaic del(6)(q22q24) was not visible using SNP array karyotyping, some of the smaller imbalances (SNP array data) could not have been detected by classic cytogenetic analysis. Therefore, our study supports the usefulness of applying complementary methods for cytogenetic analysis.

Genomic screening of head and neck cancer and its implications for therapy planning

Despite great technical improvements in radiotherapy and surgery, survival for patients with squamous cell carcinoma of the head and neck (SCCHN) has still not improved significantly over the last decades. Management of SCCHN has mainly been based on the TNM staging and site over this time period, even though we know that there are individual differences independent of the TNM status. Individual patients with small tumors might have a poor outcome, and patients with large tumors may end up with a favorable prognosis, despite their respective TNM classification. Recent molecular studies indicate that underlying genetic abnormalities may reflect such individual differences independently of TNM status. Individualization of treatment based on such biological properties of the tumors might result in less over as well as under treatment. However, the optimal panel of biomarkers to be used for the individualization of treatment is yet to be defined. A variety of laboratory techniques have been used in studies that investigate the individual biological features, spanning from methods that screen the genome for chromosomal and genetic abnormalities, e.g., cytogenetics, CGH, SKY and cDNA micro array, to detailed studies of specific aberrations. The purpose of this review of the literature is to summarize what has been studied so far by methods for genetic screening and to relate these results to the prediction of the clinical outcome. We conclude that it is time to focus future prospective studies on how treatment can be individualized based on biomarkers in combination with the macroscopic features of SCCHN.

Molecular cytogenetic analysis in the study of brain tumors: findings and applications

Classic cytogenetics has evolved from black and white to technicolor images of chromosomes as a result of advances in fluorescence in situ hybridization (FISH) techniques, and is now called molecular cytogenetics. Improvements in the quality and diversity of probes suitable for FISH, coupled with advances in computerized image analysis, now permit the genome or tissue of interest to be analyzed in detail on a glass slide. It is evident that the growing list of options for cytogenetic analysis has improved the understanding of chromosomal changes in disease initiation, progression, and response to treatment. The contributions of classic and molecular cytogenetics to the study of brain tumors have provided scientists and clinicians alike with new avenues for investigation. In this review the authors summarize the contributions of molecular cytogenetics to the study of brain tumors, encompassing the findings of classic cytogenetics, interphase- and metaphase-based FISH studies, spectral karyotyping, and metaphase- and array-based comparative genomic hybridization. In addition, this review also details the role of molecular cytogenetic techniques in other aspects of understanding the pathogenesis of brain tumors, including xenograft, cancer stem cell, and telomere length studies.

Management of paranasal sinus malignancy

Malignancies of the nasal cavity and paranasal sinuses represent a wide spectrum of histologies, tissues of origin, and anatomic primary sites. The inherent difficulty in generalizing treatment approaches is obvious, given the numerous variables associated with the broadly-based term, paranasal sinus malignancy (PNSCa). Nevertheless, the majority of epithelial and salivary malignancies of this region (ie, squamous cell carcinoma, adenocarcinoma, adenoid cystic carcinoma, sinonasal undifferentiated carcinoma, and esthesioneuroblastoma) require surgical intervention as part of any treatment regimen. Recent trends have broadened the indications for chemotherapeutic and radiotherapeutic options in the management of advanced PNSCa. Nonepithelial malignancies, including the wide variety of sarcomas arising in this region, most commonly require multimodality treatment including chemotherapy, radiation, and/or surgery for definitive treatment. Moreover, the proximity of the nasal cavity and paranasal sinuses to structures including the orbit, dura, brain, cranial nerves, and carotid arteries mandates careful radiologic and neurologic evaluations throughout the course of the disease. Surgical advances now permit complex tumor removal and reconstruction surrounding these structures resulting in functional and cosmetic improvements when compared to earlier techniques. However, additional clinical trials are necessary to systematically evaluate the locoregional control, organ-preservation strategies, and survival related to the variety of treatments currently available.

CGH pattern of esthesioneuroblastoma and their metastases

Comparative genomic hybridization (CGH) was used to screen 22 esthesioneuroblastomas (ENB) from 12 patients including 12 primary tumors and 10 metastasis/recurrent lesions for chromosomal imbalances being the most extensive study so far. The analysis revealed a characteristic pattern consisting of deletions on chromosomes 3p and overrepresentations on 17q in up to 100% of cases. Other important alterations being detectable in more than 80% of cases were deletions on 1p, 3p/q, 9p, 10p/q along with overrepresentation on 17p13, 20p and 22q. Particularly striking was the pattern for chromosomes 3, 10 and 17q and 20 being affected almost exclusively by deletions or overrepresentations, respectively. Pronounced overrepresentations suggestive for high copy amplifications were seen on 1p34, 1q23-q31, 7p21, 7q31, 9p23-p24, 17q11-q22, 17q24-q25, 19, 20p, 20q13 and 22q13. Comparing tumor pairs from the same patient revealed a high concordance indicating clonality and confirming the genetic homogeneity of the tumor entity. The analysis of metastatic/recurrent lesions indicated a higher percentage of pronounced alterations, e.g., high copy DNA gains at 1q34-qter, 7q11, 9p23-p24, 9q34, 13q33-q34, 16p13.3, 16p11, 16q23-q24 and 17p13. The analysis furthermore suggested specific alterations, e.g., deletions of chromosome 11 and gains of 1p to be associated with metastasis formation and/or worse prognosis. Our results indicate that ENB is a distinct entity and provides criteria for its genetic distinction from other small round cell tumor types.

Update in management of head and neck sarcoma

PURPOSE OF REVIEW

This update addressing head and neck sarcoma presents new data published after January 2003. This new information is presented following review of contemporary management principles established before 2003.

RECENT FINDINGS

The application of advances in molecular and genetic techniques to characterize individual sarcomas has improved classification schemes and hopefully will lead to individually tailored therapy. Maturation and refinements of large tumor registries are permitting more detailed analysis of larger contemporary series of the rare head and neck sarcomas. Improved long-term survival of patients treated for sarcoma in their childhood has allowed study of the morbidity induced by treatment. Novel treatment strategies are under study to decrease morbidity without diminishing the chance for cure.

SUMMARY

Progress in improving the treatment of sarcoma of the head and neck has been slow due to the lack of a large clinical experience with this rare neoplasm. Advances continue and are anticipated to be most striking in the study of genetic mechanisms.