PGLNext

PGLNextTM is a next generation sequencing panel that simultaneously analyzes 12 genes associated with an increased risk of developing paragangliomas (PGLs) and/or pheochromocytomas (PCCs).

PrintPrint

PGLNextTM is a next generation sequencing panel that simultaneously analyzes 12 genes associated with an increased risk of developing paragangliomas (PGLs) and/or pheochromocytomas (PCCs).

Ambry utilizes next generation sequencing (NGS) to offer a comprehensive hereditary PGL/PCC panel.  Genes on this panel include FH, MAX, MEN1, NF1, RET, SDHA, SDHAF2, SDHB, SDHC, SDHD, TMEM127, VHL. Full gene sequencing and gross deletion/duplication analysis is performed for all 12 genes. Specific Site Analysis is available for individual gene mutations identified in a family.

Disease Name 
Hereditary cancer
Hereditary paraganglioma-pheochromocytoma syndrome
Neuroendocrine tumors
Paraganglioma
Pheochromocytoma
Disease Information 

Paragangliomas (PGLs) are often benign, neuroendocrine tumors of the autonomic nervous system originating from the external ganglia. Pheochromocytomas (PCCs) are paragangliomas that are confined to the adrenal medulla. PGLs are further subdivided into sympathetic and parasympathetic tumors, depending upon their site of origin. Sympathetic PGLs commonly hypersecrete catecholamines and are typically located in the chest, abdomen and pelvis. Parasympathetic PGLs are primarily non-secretory and occur along the nerves in the head, the neck, and the upper mediastinum (termed head and neck PGLs or HNPGLs).1,2  The prevalence of PGLs in the U.S. is 1 in 2,500 to 1 in 6,500, although this is likely an underestimate. The average age of diagnosis is between 40-50 years.2,3  Approximately 75% of PGL/PCCs are benign; however, morbidity and mortality are associated with high levels of circulating catecholamines, which can lead to hypertension and stroke.1,3  Published population studies have found that at least 10-30% individuals with PGL/PCCs have an inherited germline mutation in one of the known susceptibility genes.1,4-6

PGLNext Genes:

FH is a gene associated with hereditary leiomyomatosis and renal cell cancer (HLRCC). HLRCC is characterized by an increased lifetime risk of developing papillary type 2 renal tumors, with a lifetime risk of up to 20% for renal cancer and nearly 98% risk of cutaneous and uterine leiomyomas/fibroids.(7) HLRCC-associated renal tumors are more likely to present as unilateral solitary lesions, with about 20% of individuals identified in their forties at an age range of 17-75 years. Almost all female HLRCC mutation carriers have uterine fibroids, with a mean age of diagnosis at 30 years, and an age range of 18-52 years.7-10  Although uterine fibroids are common in the general population, the fibroids in women with HLRCC tend to be larger and more numerous. In addition, mutations in the FH gene have recently been reported in individuals with malignant pheochromocytomas and paragangliomas.11,12

MAX is a tumor suppressor gene associated with PCC susceptibility. In one study of twelve MAX mutation carriers with PCC, 25% of patients showed metastasis, suggesting that, similar to SDHB, MAX mutations are associated with an increased metastatic potential.13  The exact PCC lifetime risk is not yet established for MAX mutation carriers. Seemingly sporadic PCCs may be due to paternal transmission of the mutant allele.1,3,13

MEN1 mutations cause multiple endocrine neoplasia type 1 (MEN1) and familial isolated hyperparathyroidism (FIHP). FIHP is defined by primary hyperparathyroidism as the sole endocrinopathy in a family.14  In contrast, MEN1 is characterized by primary hyperparathyroidism due to parathyroid adenomas (present in over 90% of affected individuals), gastro-entero-pancreatic neuroendocrine tumors (in 30-70%), pituitary adenomas (in 30-60%), adrenocortical tumors (15-50%), bronchial and thymic carcinoids (up to 10%), facial angiofibromas, collagenomas, and lipomas.15-20  The majority of patients (94%) carrying a mutation in the MEN1 gene exhibit clinical or biochemical symptoms by age 50.21

NF1 mutations cause neurofibromatosis type 1 (NF1), an autosomal dominant disorder affecting multiple body systems. It is characterized by multiple café-au-lait spots, axillary and inguinal freckling, multiple cutaneous neurofibromas, and Lisch nodules. The most common neoplasms observed in individuals with NF1 include peripheral nerve sheath tumors, gastrointestinal stromal tumors (GIST), central nervous system gliomas, leukemias, paragangliomas (PGLs) and pheochromocytomas (PCCs), and breast cancer. Multiple population-based studies have demonstrated a 3 to 5-fold increase in lifetime breast cancer risk for women with NF1, with the highest risks for those less than 50 years of age. In addition, individuals with NF1 have an estimated lifetime risk for PGLs and PCCs of up to 7%.

RET is a proto-oncogene associated with multiple endocrine neoplasia type 2 (MEN2). MEN2 is an autosomal dominant disorder characterized by the presence of benign or malignant endocrine system tumors. MEN2 is divided into three clinical subtypes: MEN2A (>90% of patients), MEN2B, and familial medullary thyroid carcinoma (FMTC). MEN2-associated PCCs are often multifocal and bilateral, with a median age of diagnosis between 30-40 years.1,3,22

SDHA, SDHB, SDHC, SDHD, and SDHAF2 are all genes associated with hereditary paraganglioma and pheochromocytoma (PGL/PCC) syndrome. Germline mutations in these genes have been associated with susceptibility to head and neck paragangliomas (HNPGLs), extra-adrenal PGLs/PCCs and, rarely, renal cell carcinoma (RCC) with gastrointestinal stromal tumors (Carney-Stratakis syndrome).23  SDHB associated RCC can be of varied histology with reported cases of clear cell, papillary, granular, and mixed.24,25  The exact lifetime risk for PCC is not yet established for SDHB mutation carriers.26  The SDHD and SDHAF2 genes are subject to the effects of imprinting (parent-of-origin effects), and cancer risk is correlated with paternal transmission.27-29  Mutations in the SDH genes have also been associated with PTEN mutation-negative Cowden syndrome.30

TMEM127 is a proposed tumor suppressor gene associated with PGL/PCC susceptibility.31 TMEM127 mutations demonstrate an autosomal dominant pattern of inheritance with unknown penetrance.1,3 TMEM127-associated PCCs can present bilaterally or unilaterally, and may also be found in patients with no family history of PCC.26,31  One study reported TMEM127 mutations in 2 of 48 patients with PGL.31

VHL mutations are associated with von Hippel-Lindau disease (VHL). VHL is an autosomal dominant cancer predisposition syndrome with about a 20% de novo mutation32 rate and an estimated incidence of 1 in 36,000.8  VHL is characterized by renal tumors, adrenal pheochromocytoma (PCC), retinal angiomas, central nervous system hemangioblastomas, pancreatic cysts, and neuroendocrine tumors. The associated lifetime risk of RCC in those with VHL is estimated at 25-70%, depending on disease subtype. VHL-associated renal tumors tend to be earlier-onset (average age of diagnoses is 39 years) and multifocal.32  Published literature supports that patients carrying a partial germline VHL gene deletion have a higher RCC risk than those carrying full-gene deletions.8,10

Testing Benefits & Indication 

Recent data and guidelines suggest that all individuals with a PGL or PCC should be offered diagnostic testing for PGL/PCC susceptibility.4  Increased surveillance and treatment is available for those found to carry a mutation.33

Common Red Flags for Hereditary Cancer

  • Cancer diagnosed at a younger age than expected for the general population (≤ 50 years, for most cancers)
  • Cancer diagnosed across generations, and in multiple generations within a family, especially when diagnosed younger than average (on the same side of the family)
  • Individual with multiple primary cancers (either in paired organs or in different organs)
  • A pattern of cancer in the family that is typical of a known cancer predisposition syndrome (e.g. PCC and renal cell carcinoma with VHL)

Benefits of Testing
Identifying patients with an inherited susceptibility for PGL/PCC can help with medical management and risk assessment. For example, this information can:

  • Modify surveillance options and age of initial screening
  • Suggest specific risk-reduction measures 
  • Clarify and stratify familial cancer risks, based on gene-specific associations
  • Offer treatment guidance 
  • Identify at-risk family members
  • Provide guidance with new gene-specific treatment options and risk reduction measures as they emerge
Test Description 

PGLNext analyzes 12 genes (listed above). All genes are evaluated by next generation sequencing (NGS) or Sanger sequencing of all coding domains, and well into the flanking 5’ and 3’ ends of all the introns and untranslated regions. Clinically significant intronic findings beyond 5 base pairs are always reported. Intronic variants of unknown or unlikely clinical significance are not reported beyond 5 base pairs from the splice junction. Additional Sanger sequencing is performed for any regions missing or with insufficient read depth coverage for reliable heterozygous variant detection. Reportable small insertions and deletions, potentially homozygous variants, variants in regions complicated by pseudogene interference, and single nucleotide variant calls not satisfying 100x depth of coverage and 40% het ratio thresholds are verified by Sanger sequencing.34  Gross deletion/duplication analysis is performed for the covered exons and untranslated regions of all 12 genes using read-depth from NGS data with confirmatory multiplex ligation-dependent probe amplification (MLPA) and/or targeted chromosomal microarray.

Mutation Detection Rate 

PGLNext can detect >99.9% of described mutations in the included genes listed above, when present (analytic sensitivity).

Specimen Requirements 

Complete specimen requirements are available here or by downloading the PDF found above on this page.

Turnaround Time 
TEST CODE TEST NAME TURNAROUND TIME (days)
5504 PGLNext 14 - 21

 

Specialty 
Genes 
FH
MAX
MEN1
NF1
RET
SDHA
SDHAF2
SDHB
SDHC
SDHD
TMEM127
VHL
References 
  1. Fishbein L, Nathanson KL. Pheochromocytoma and paraganglioma: understanding the complexities of the genetic background. Cancer genetics. 2012;205(1-2):1-11. 
  2. Welander J, Soderkvist P, Gimm O. Genetics and clinical characteristics of hereditary pheochromocytomas and paragangliomas. Endocrine-Related Cancer. 2011;18(6):R253-76. 
  3. DeLellis RA. Pathology and genetics of tumours of endocrine organs. Lyon, France: IARC Press; 2004.
  4. Fishbein L, et al. Inherited mutations in pheochromocytoma and paraganglioma: why all patients should be offered genetic testing. Annals of Surgical Oncology. 2013;20(5):1444-50. 
  5. Mannelli M, et al. Clinically guided genetic screening in a large cohort of italian patients with pheochromocytomas and/or functional or nonfunctional paragangliomas. J Clin Endocrinol Metab. 2009;94(5):1541-7. 
  6. Mannelli M, et al. Subclinical phaeochromocytoma. Best Prac Res Clin Endocrinol Metab. 2012;26(4):507-15. 
  7. Gardie B, et al. Novel FH mutations in families with hereditary leiomyomatosis and renal cell cancer (HLRCC) and patients with isolated type 2 papillary renal cell carcinoma. J Med Genet. 2011;48(4):226-34. 
  8. Barrisford GW, et al. Familial renal cancer: molecular genetics and surgical management. International Journal of Surgical Oncology. 2011;2011:658767. 
  9. Coleman JA, Russo P. Hereditary and familial kidney cancer. Current Opinion in Urology. 2009;19(5):478-85. 
  10. Rini BI, Campbell SC, Rathmell WK. Renal cell carcinoma. Current Opinion in Oncology. 2006;18(3):289-96. 
  11. Castro-Vega LJ, et al. Germline mutations in FH confer predisposition to malignant pheochromocytomas and paragangliomas. Hum Mol Genet. 2014;23(9):2440-6. 
  12. Clark GR, et al. Germline FH mutations presenting with pheochromocytoma. J Clin Endocrinol Metab. 2014;99(10):E2046-50. 
  13. Comino-Mendez I, et al. Exome sequencing identifies MAX mutations as a cause of hereditary pheochromocytoma. Nat Genet. 2011;43(7):663-7. 
  14. Hannan FM, et al. Familial isolated primary hyperparathyroidism caused by mutations of the MEN1 gene. Nature Clinical Practice Endocrinology & Metabolism. 2008;4(1):53-8.
  15. Machens A, et al. Age-related penetrance of endocrine tumours in multiple endocrine neoplasia type 1 (MEN1): a multicentre study of 258 gene carriers. Clinical Endocrinology. 2007;67:613-22.
  16. Thakker RV, et al. Clinical practice guidelines for multiple endocrine neoplasia type 1 (MEN1). J Clin Endocrinol Metab. 2012;97(2990-3011):2990.
  17. Carty SE, et al. The variable penetrance and spectrum of manifestations of multiple endocrine neoplasia type 1. Surgery. 1998;124(6):1106-14.
  18. Gibril F, et al. Prospective study of thymic carcinoids in patients with multiple endocrine neoplasia type 1. J Clin Endocrinol Metab. 2003;88(3):1066-81.
  19. Marx SJ, et al. Multiple endocrine neoplasia type 1: clinical and genetic topics. Ann Intern Med. 1998;129:484-94.
  20. Waldmann J, et al. Adrenal involvement in multiple endocrine neoplasia type 1: results of 7 years prospective screening. Langenbecks Arch Surg. 2007;392:437-43.
  21. Chandrasekharappa SC, et al. Positional cloning of the gene for multiple endocrine neoplasia–type 1. Science. 1997;276:404-7.
  22. Eng C, et al. The relationship between specific RET proto-oncogene mutations and disease phenotype in multiple endocrine neoplasia type 2. International RET Mutation Cnsortium analysis. JAMA. 1996;276(19):1575-9. 
  23. Carney JA, Stratakis CA. Familial paraganglioma and gastric stromal sarcoma: a new syndrome distinct from the Carney triad. Am J Med Genet. 2002;108(2):132-9. 
  24. Ricketts C, et al. Germline SDHB mutations and familial renal cell carcinoma. Journal of the National Cancer Institute. 2008;100(17):1260-2. 
  25. Vanharanta S, et al. Early-onset renal cell carcinoma as a novel extraparaganglial component of SDHB-associated heritable paraganglioma. Am J Hum Genet. 2004;74(1):153-9. 
  26. Ricketts CJ, et al. Tumor risks and genotype-phenotype-proteotype analysis in 358 patients with germline mutations in SDHB and SDHD. Hum Mutat. 2010;31(1):41-51. 
  27. Baysal BE. Mitochondrial complex II and genomic imprinting in inheritance of paraganglioma tumors. Biochim Biophys Acta. 2013;1827(5):573-7. 
  28. Hao HX, et al. SDH5, a gene required for flavination of succinate dehydrogenase, is mutated in paraganglioma. Science. 2009;325(5944):1139-42. 
  29. Kunst HP, et al. SDHAF2 (PGL2-SDH5) and hereditary head and neck paraganglioma. Clin Cancer Res. 2011;17(2):247-54. 
  30. Ni Y, et al. Germline mutations and variants in the succinate dehydrogenase genes in Cowden and Cowden-like syndromes. Am J Hum Genet. 2008;83(2):261-8. 
  31. Neumann HP, et al. Germline mutations of the TMEM127 gene in patients with paraganglioma of head and neck and extraadrenal abdominal sites. J Clin Endocrinol Metab. 2011;96(8):E1279-82. 
  32. Lonser RR, et al. von Hippel-Lindau disease. Lancet. 2003;361(9374):2059-67.
  33. Lenders JWM, et al. Pheochromocytoma and paraganglioma: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2014;99:1915-42.
  34. Mu W, et al. Sanger confirmation is required to achieve optimal sensitivity and specificity in next-generation sequencing panel testing. J Mol Diagn. 2016. 18(6):923-932.