ABSTRACT
Hereditary SDHB-mutant pheochromocytomas (PC) and paragangliomas (PG) are rare tumours with a high propensity to metastasize although their clinical behaviour is unpredictable. To characterize the genomic landscape of these tumours and identify metastasis biomarkers, we performed multi-omic analysis on 94 tumours from 79 patients using seven molecular methods. Sympathetic (chromaffin cell) and parasympathetic (non-chromaffin cell) PCPG had distinct molecular profiles reflecting their cell-of-origin and biochemical profile. TERT and ATRX-alterations were associated with metastatic PCPG and these tumours had an increased mutation load, and distinct transcriptional and telomeric features. Most PCPG had quiet genomes with some rare co-operative driver events observed, including EPAS1/HIF-2α mutations. Two mechanisms of acquired resistance to DNA alkylating chemotherapies were also detected - MGMT overexpression and mismatch repair-deficiency causing hypermutation. Our comprehensive multi-omic analysis of SDHB-mutant PCPG therefore identified features of metastatic disease and treatment response, expanding our understanding of these rare neuroendocrine tumours.
Subject(s)
Carcinoid Tumor , Female , Humans , Middle Aged , Carcinoid Tumor/pathology , Carcinoid Tumor/diagnosisABSTRACT
Genetic mutations accumulate in an organism's body throughout its lifetime. While somatic single-nucleotide variants have been well characterized in the human body, the patterns and consequences of large chromosomal alterations in normal tissues remain largely unknown. Here, we present a pan-tissue survey of mosaic chromosomal alterations (mCAs) in 948 healthy individuals from the Genotype-Tissue Expression project, augmenting RNA-based allelic imbalance estimation with haplotype phasing. We found that approximately a quarter of the individuals carry a clonally-expanded mCA in at least one tissue, with incidence strongly correlated with age. The prevalence and genome-wide patterns of mCAs vary considerably across tissue types, suggesting tissue-specific mutagenic exposure and selection pressures. The mCA landscapes in normal adrenal and pituitary glands resemble those in tumors arising from these tissues, whereas the same is not true for the esophagus and skin. Together, our findings show a widespread age-dependent emergence of mCAs across normal human tissues with intricate connections to tumorigenesis.
Subject(s)
Chromosome Aberrations , Neoplasms , Humans , Mutation , Neoplasms/genetics , Allelic Imbalance , EsophagusABSTRACT
The pathology of neoplasia tends to focus on the tumor that requires characterization, grading, and staging. However, nontumorous tissue surrounding the lesion can also provide information, particularly about pathogenetic mechanisms. In endocrine tissues, this takes the form of precursor lesions that characterize several genetic predisposition syndromes. In addition, because of the unique functional aspects of endocrine neoplasia, the nontumorous tissue provides evidence of hormone excess, with hyperplasia and/or atrophy and other involutional changes allowing the pathologist to confirm both hormone function by the tumor and the effects of medical therapies. In this article, we review the various clinically relevant features that should be assessed and reported to enhance clinical management of patients with endocrine neoplasms. For example, in thyroid there may be inflammatory thyroiditis or goiter of various etiologies; there may be C-cell hyperplasia either as a preneoplastic lesion in patients with genetic predisposition to medullary thyroid carcinoma or as a reactive phenomenon. Drug-induced changes can be seen in thyroid and adrenal cortex. In neuroendocrine tissues, the nontumorous tissues may show precursor lesions such as endocrine cell hyperplasia/dysplasia; there may be related or unrelated hyperplastic or neoplastic lesions. Some tissues, such as pituitary corticotrophs and adrenal cortex, develop changes that reflect feedback suppression by hormone excess that can serve as biomarkers of tumor functionality and provide enhanced clinicopathologic correlates.
Subject(s)
Endocrine Gland Neoplasms , Thyroid Neoplasms , Humans , Hyperplasia , Thyroid Neoplasms/pathology , Genetic Predisposition to Disease , HormonesABSTRACT
Experimental models for pheochromocytoma and paraganglioma are needed for basic pathobiology research and for preclinical testing of drugs to improve treatment of patients with these tumors, especially patients with metastatic disease. The paucity of models reflects the rarity of the tumors, their slow growth, and their genetic complexity. While there are no human cell line or xenograft models that faithfully recapitulate the genotype or phenotype of these tumors, the past decade has shown progress in development and utilization of animal models, including a mouse and a rat model for SDH-deficient pheochromocytoma associated with germline Sdhb mutations. There are also innovative approaches to preclinical testing of potential treatments in primary cultures of human tumors. Challenges with these primary cultures include how to account for heterogeneous cell populations that will vary depending on the initial tumor dissociation and how to distinguish drug effects on neoplastic vs normal cells. The feasible duration for maintaining cultures must also be balanced against time required to reliably assess drug efficacy. Considerations potentially important for all in vitro studies include species differences, phenotype drift, changes that occur in the transition from tissue to cell culture, and the O2 concentration in which cultures are maintained.
Subject(s)
Adrenal Gland Neoplasms , Paraganglioma , Pheochromocytoma , Humans , Mice , Rats , Animals , Pheochromocytoma/pathology , Paraganglioma/genetics , Succinate Dehydrogenase/genetics , Germ-Line Mutation , Adrenal Gland Neoplasms/pathology , Models, TheoreticalABSTRACT
Pheochromocytomas (PC) and paragangliomas (PG) are rare neuroendocrine tumors associated with autonomic nerves. Here we use single-nuclei RNA-seq and bulk-tissue gene-expression data to characterize the cellular composition of PCPG and normal adrenal tissues, refine tumor gene-expression subtypes and make clinical and genotypic associations. We confirm seven PCPG gene-expression subtypes with significant genotype and clinical associations. Tumors with mutations in VHL, SDH-encoding genes (SDHx) or MAML3-fusions are characterized by hypoxia-inducible factor signaling and neoangiogenesis. PCPG have few infiltrating lymphocytes but abundant macrophages. While neoplastic cells transcriptionally resemble mature chromaffin cells, early chromaffin and neuroblast markers are also features of some PCPG subtypes. The gene-expression profile of metastatic SDHx-related PCPG indicates these tumors have elevated cellular proliferation and a lower number of non-neoplastic Schwann-cell-like cells, while GPR139 is a potential theranostic target. Our findings therefore clarify the diverse transcriptional programs and cellular composition of PCPG and identify biomarkers of potential clinical significance.
Subject(s)
Adrenal Gland Neoplasms , Paraganglioma , Pheochromocytoma , Humans , Pheochromocytoma/genetics , Tumor Microenvironment/genetics , Paraganglioma/genetics , Paraganglioma/pathology , Adrenal Gland Neoplasms/genetics , Adrenal Gland Neoplasms/pathology , Succinate Dehydrogenase/geneticsSubject(s)
Awards and Prizes , Biomedical Research , Endocrinology , Achievement , Biomedical Research/history , Endocrinology/history , Endocrinology/organization & administration , Faculty, Medical/history , History, 20th Century , History, 21st Century , Humans , Massachusetts , New York , Pathology, Clinical/history , Societies, Medical/organization & administrationSubject(s)
Adenocarcinoma/secondary , Pituitary Neoplasms/secondary , Salivary Gland Neoplasms/pathology , Adenocarcinoma/diagnosis , Adenocarcinoma/pathology , Adenocarcinoma/surgery , Biomarkers, Tumor/analysis , Female , Humans , Keratin-7/analysis , Magnetic Resonance Imaging , Middle Aged , Pituitary Gland/pathology , Pituitary Neoplasms/diagnosis , Pituitary Neoplasms/pathology , Pituitary Neoplasms/surgery , Salivary Gland Neoplasms/diagnosis , Salivary Gland Neoplasms/surgery , Tomography, X-Ray ComputedABSTRACT
This morphological and immunohistochemical study demonstrates that tumors currently known as "middle ear adenomas" are truly well-differentiated epithelial neuroendocrine tumors (NETs) composed of cells comparable to normal intestinal L cells, and therefore, these tumors resemble hindgut NETs. These tumors show consistent expression of glucagon, pancreatic polypeptide, PYY, and the transcription factor SATB2, as well as generic neuroendocrine markers and keratins. The same L cell markers are expressed by cells within the normal middle ear epithelium. These markers define a valuable immunohistochemical profile that can be used for differential diagnosis of middle ear neoplasms, particularly in distinguishing epithelial NETs from paragangliomas. The discovery of neuroendocrine cells expressing the same markers in non-neoplastic middle ear mucosa opens new areas of investigation into the physiology of the normal middle ear and the pathophysiology of middle ear disorders.
Subject(s)
Adenoma/diagnosis , Ear Neoplasms/diagnosis , Ear, Middle/pathology , L Cells/physiology , Neuroendocrine Tumors/diagnosis , Adenoma/classification , Adenoma/metabolism , Adenoma/pathology , Adult , Aged , Animals , Cell Differentiation , Diagnosis, Differential , Ear Neoplasms/classification , Ear Neoplasms/metabolism , Ear Neoplasms/pathology , Ear, Middle/metabolism , Female , Humans , Immunohistochemistry , L Cells/metabolism , L Cells/pathology , Male , Mice , Middle Aged , Neuroendocrine Tumors/classification , Neuroendocrine Tumors/metabolism , Neuroendocrine Tumors/pathology , Retrospective Studies , Terminology as TopicABSTRACT
Characterization of the progression of cellular states during human embryogenesis can provide insights into the origin of pediatric diseases. We examined the transcriptional states of neural crest- and mesoderm-derived lineages differentiating into adrenal glands, kidneys, endothelium and hematopoietic tissue between post-conception weeks 6 and 14 of human development. Our results reveal transitions connecting the intermediate mesoderm and progenitors of organ primordia, the hematopoietic system and endothelial subtypes. Unexpectedly, by using a combination of single-cell transcriptomics and lineage tracing, we found that intra-adrenal sympathoblasts at that stage are directly derived from nerve-associated Schwann cell precursors, similarly to local chromaffin cells, whereas the majority of extra-adrenal sympathoblasts arise from the migratory neural crest. In humans, this process persists during several weeks of development within the large intra-adrenal ganglia-like structures, which may also serve as reservoirs of originating cells in neuroblastoma.
Subject(s)
Cell Lineage , Embryo, Mammalian/metabolism , Neuroblastoma/embryology , Neuroblastoma/genetics , Single-Cell Analysis , Sympathoadrenal System/embryology , Transcriptome/genetics , Animals , Chromaffin Cells/metabolism , Chromaffin Cells/pathology , Cluster Analysis , Embryonic Development , Gene Expression Regulation, Developmental , Gene Expression Regulation, Neoplastic , Humans , Infant , Mice , Neural Stem Cells/metabolism , Neuroblastoma/pathology , Schwann Cells/metabolism , Schwann Cells/pathology , Tumor MicroenvironmentABSTRACT
Recent advances in molecular genetics and genomics have led to increased understanding of the aetiopathogenesis of pheochromocytomas and paragangliomas (PPGLs). Thus, pan-genomic studies now provide a comprehensive integrated genomic analysis of PPGLs into distinct molecularly defined subtypes concordant with tumour genotypes. In addition, new embryological discoveries have refined the concept of how normal paraganglia develop, potentially establishing a developmental basis for genotype-phenotype correlations for PPGLs. The challenge for modern pathology is to translate these scientific discoveries into routine practice, which will be based largely on histopathology for the foreseeable future. Here, we review recent progress concerning the cell of origin and molecular pathogenesis of PPGLs, including pathogenetic mechanisms, genetic susceptibility and molecular classification. The current roles and tools of pathologists are considered from a histopathological perspective, including differential diagnoses, genotype-phenotype correlations and the use of immunohistochemistry in identifying hereditary predisposition and validating genetic variants of unknown significance. Current and potential molecular prognosticators are also presented with the hope that predictive molecular biomarkers will be integrated into risk stratification scoring systems to assess the metastatic potential of these intriguing neoplasms and identify potential drug targets.
Subject(s)
Adrenal Gland Neoplasms/genetics , Adrenal Gland Neoplasms/pathology , Paraganglioma/genetics , Paraganglioma/pathology , Pheochromocytoma/genetics , Pheochromocytoma/pathology , Genetic Predisposition to Disease , Genomics , Genotype , HumansABSTRACT
BACKGROUND: Paragangliomas (PGLs) are rare neoplasms that may be associated with hereditary PGL syndromes and variable risk of metastasis. Middle ear adenomas are extremely rare tumors with no known hereditary predisposition and extremely low risk of metastasis. Although often easily differentiated, they may share clinical and pathological features that misdirect and confuse the diagnosis. OBSERVATIONS: The authors discussed a 35-year-old woman with left-sided hearing loss and bleeding from the external ear canal who presented to an outside hospital. She underwent resection of a middle ear and mastoid mass, initially diagnosed as a middle ear adenoma with neuroendocrine features, with later mastoidectomy and ligation of the sigmoid sinus with microsurgical excision of persistent tumor in the jugular foramen and temporal bone. Histopathologically, her tumor was vascular, composed of benign-appearing epithelioid cells with "salt and pepper" neuroendocrine chromatin arranged in vague nests. Lesional cells were GATA3-immunopositive, glucagon-negative, and succinate dehydrogenase-immunonegative, consistent with PGL rather than middle ear adenoma, and required further workup for hereditary PGL syndromes. LESSONS: This case demonstrates potential challenges in differentiating a PGL from a middle ear adenoma. The authors offer clinical, histopathological, and imaging principles to aid in diagnosis and workup.
ABSTRACT
BACKGROUND AND OBJECTIVES: The International Collaboration on Cancer Reporting (ICCR) is a not-for-profit to develop evidence-based, internationally agreed-upon standardized data sets for each anatomic site, to be used throughout the world. Providing global standardization of pathology tumor classification, staging, and other reporting elements will lead to improved patient management and enhanced epidemiological research. METHODS: Pheochromocytoma and paraganglioma are uncommon and are frequently overlooked in registry data sets. Malignant criteria have previously been defined only when there was metastatic disease. RESULTS: With recent recognition of a significant inheritance association and the development of risk stratification tools, this data set was created in order to obtain more meaningful outcomes and management data, using similar criteria across the global pathology community. Issues related to key core and non-core elements, especially clinical hormonal status, familial history, tumor focality, proliferative fraction, adverse or risk stratification features, and ancillary techniques, are discussed in the context of daily application to these types of specimens. CONCLUSIONS: The ICCR data set, developed by an international panel of endocrine organ specialists, establishes a pathology-standardized reporting guide for pheochromocytoma and paraganglioma.
Subject(s)
Adrenal Gland Neoplasms/pathology , Carcinoma/pathology , Pathology, Clinical/standards , Pheochromocytoma/pathology , Research Design/standards , Humans , Paraganglioma/pathologySubject(s)
Adrenal Gland Neoplasms/therapy , Pheochromocytoma/therapy , Adrenal Gland Neoplasms/diagnosis , Adrenal Gland Neoplasms/diagnostic imaging , Adrenal Gland Neoplasms/genetics , Adult , Female , Humans , Male , Middle Aged , Neoplasm Metastasis , Pheochromocytoma/diagnosis , Pheochromocytoma/diagnostic imaging , Pheochromocytoma/geneticsSubject(s)
Endothelial Cells/metabolism , Paraganglioma/metabolism , SOXE Transcription Factors/metabolism , Succinate Dehydrogenase/genetics , Adrenal Gland Neoplasms/genetics , Adrenal Gland Neoplasms/metabolism , Adrenal Gland Neoplasms/pathology , Adult , Biomarkers, Tumor/metabolism , Endothelial Cells/pathology , Female , Germ-Line Mutation , Humans , Immunity, Innate/physiology , Immunohistochemistry , Inflammation Mediators/metabolism , Male , Neuroendocrine Cells/metabolism , Neuroendocrine Cells/pathology , Paraganglioma/genetics , Paraganglioma/pathology , Pheochromocytoma/genetics , Pheochromocytoma/metabolism , Pheochromocytoma/pathology , Staining and Labeling , Succinate Dehydrogenase/deficiency , Succinate Dehydrogenase/metabolismABSTRACT
BACKGROUND: Pheochromocytomas (PCCs) and paragangliomas (PGLs) are neuroendocrine tumors that are mostly benign. Metastatic disease does occur in about 10% of cases of PCC and up to 25% of PGL, and for these patients no effective therapies are available. Patients with mutations in the succinate dehydrogenase subunit B (SDHB) gene tend to have metastatic disease. We hypothesized that a down-regulation in the active succinate dehydrogenase B subunit should result in notable changes in cellular metabolic profile and could present a vulnerability point for successful pharmacological targeting. METHODS: Metabolomic analysis was performed on human hPheo1 cells and shRNA SDHB knockdown hPheo1 (hPheo1 SDHB KD) cells. Additional analysis of 115 human fresh frozen samples was conducted. In vitro studies using N1,N11-diethylnorspermine (DENSPM) and N1,N12- diethylspermine (DESPM) treatments were carried out. DENSPM efficacy was assessed in human cell line derived mouse xenografts. RESULTS: Components of the polyamine pathway were elevated in hPheo1 SDHB KD cells compared to wild-type cells. A similar observation was noted in SDHx PCC/PGLs tissues compared to their non-mutated counterparts. Specifically, spermidine, and spermine were significantly elevated in SDHx-mutated PCC/PGLs, with a similar trend in hPheo1 SDHB KD cells. Polyamine pathway inhibitors DENSPM and DESPM effectively inhibited growth of hPheo1 cells in vitro as well in mouse xenografts. CONCLUSIONS: This study demonstrates overactive polyamine pathway in PCC/PGL with SDHB mutations. Treatment with polyamine pathway inhibitors significantly inhibited hPheo1 cell growth and led to growth suppression in xenograft mice treated with DENSPM. These studies strongly implicate the polyamine pathway in PCC/PGL pathophysiology and provide new foundation for exploring the role for polyamine analogue inhibitors in treating metastatic PCC/PGL. PRéCIS: Cell line metabolomics on hPheo1 cells and PCC/PGL tumor tissue indicate that the polyamine pathway is activated. Polyamine inhibitors in vitro and in vivo demonstrate that polyamine inhibitors are promising for malignant PCC/PGL treatment. However, further research is warranted.
Subject(s)
Adrenal Gland Neoplasms/drug therapy , Biogenic Polyamines/antagonists & inhibitors , Paraganglioma/drug therapy , Pheochromocytoma/drug therapy , Adrenal Gland Neoplasms/genetics , Adrenal Gland Neoplasms/metabolism , Animals , Biogenic Polyamines/metabolism , Cell Line, Tumor , Humans , Male , Metabolomics , Mice , Mutation , Paraganglioma/genetics , Paraganglioma/metabolism , Pheochromocytoma/genetics , Pheochromocytoma/metabolism , Succinate Dehydrogenase/genetics , Xenograft Model Antitumor AssaysABSTRACT
Phaeochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumours with a hereditary background in over one-third of patients. Mutations in succinate dehydrogenase (SDH) genes increase the risk for PPGLs and several other tumours. Mutations in subunit B (SDHB) in particular are a risk factor for metastatic disease, further highlighting the importance of identifying SDHx mutations for patient management. Genetic variants of unknown significance, where implications for the patient and family members are unclear, are a problem for interpretation. For such cases, reliable methods for evaluating protein functionality are required. Immunohistochemistry for SDHB (SDHB-IHC) is the method of choice but does not assess functionality at the enzymatic level. Liquid chromatography-mass spectrometry-based measurements of metabolite precursors and products of enzymatic reactions provide an alternative method. Here, we compare SDHB-IHC with metabolite profiling in 189 tumours from 187 PPGL patients. Besides evaluating succinate:fumarate ratios (SFRs), machine learning algorithms were developed to establish predictive models for interpreting metabolite data. Metabolite profiling showed higher diagnostic specificity compared to SDHB-IHC (99.2% versus 92.5%, p = 0.021), whereas sensitivity was comparable. Application of machine learning algorithms to metabolite profiles improved predictive ability over that of the SFR, in particular for hard-to-interpret cases of head and neck paragangliomas (AUC 0.9821 versus 0.9613, p = 0.044). Importantly, the combination of metabolite profiling with SDHB-IHC has complementary utility, as SDHB-IHC correctly classified all but one of the false negatives from metabolite profiling strategies, while metabolite profiling correctly classified all but one of the false negatives/positives from SDHB-IHC. From 186 tumours with confirmed status of SDHx variant pathogenicity, the combination of the two methods resulted in 185 correct predictions, highlighting the benefits of both strategies for patient management. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Subject(s)
Adrenal Gland Neoplasms/diagnosis , Head and Neck Neoplasms/diagnosis , Machine Learning , Metabolomics , Paraganglioma/diagnostic imaging , Pheochromocytoma/diagnosis , Succinate Dehydrogenase/genetics , Adrenal Gland Neoplasms/genetics , Adrenal Gland Neoplasms/pathology , Cohort Studies , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/pathology , Humans , Immunohistochemistry , Mutation , Paraganglioma/genetics , Paraganglioma/pathology , Pheochromocytoma/genetics , Pheochromocytoma/pathologyABSTRACT
Forty years ago, physicians caring for the J-kindred, a 100+ member family with multiple endocrine neoplasia type 2A (MEN2A), hypothesized that early thyroidectomy based on measurement of the biomarker calcitonin could cure patients at risk for development of medullary thyroid carcinoma (MTC). We re-evaluated 22 family members with proven RET proto-oncogene mutations (C634G) who underwent thyroidectomy and central lymphadenectomy between 1972 and 1994 based on stimulated calcitonin abnormalities. Current disease status was evaluated by serum calcitonin measurement and neck ultrasound in 18 of the 22 prospectively screened patients. The median age of the cohort at thyroidectomy was 16.5 years (range 9-24). The median duration of follow-up at the time of examination was 40 years (range 21-43) with a median current age of 52 years (range 34-65). Fifteen of the 18 patients had no detectable serum calcitonin (<2 pg/mL). Three had detectable serum calcitonin measurements, inappropriately elevated following total thyroidectomy. None of the 16 patients imaged had an abnormal ultrasound. Survival analysis shows no MTC-related deaths in the prospectively screened patients, whereas there were many in prior generations. Early thyroidectomy based on biomarker testing has rendered 15 of 18 MEN2A patients (83%) calcitonin-free with a median follow-up period of 40 years. There have been no deaths in the prospectively screened and thyroidectomized group. We conclude that early thyroidectomy and central lymph node dissection is an effective prophylactic treatment for hereditary MTC.