sábado, 18 de enero de 2020

Genetics of Endocrine and Neuroendocrine Neoplasias (PDQ®)–Health Professional Version - National Cancer Institute

Genetics of Endocrine and Neuroendocrine Neoplasias (PDQ®)–Health Professional Version - National Cancer Institute

National Cancer Institute



Genetics of Endocrine and Neuroendocrine Neoplasias (PDQ®)–Health Professional Version

Carney-Stratakis Syndrome

Clinical Description

Carney-Stratakis syndrome (CSS; also known as Carney-Stratakis dyad) was first described in 2002. Although similarly named, this syndrome is distinctly different from Carney complex and Carney triad (refer to Table 6). CSS is characterized by an autosomal dominant germline pathogenic variant in the succinate dehydrogenase (SDH) subunit BC, or D (SDHxgenes that demonstrates incomplete penetranceAffected individuals develop multifocal, locally aggressive gastrointestinal stromal tumors (GISTs) and multiple neck, intrathoracic, and intra-abdominal paragangliomas (PGLs) at relatively early ages.[1-3] CSS-associated GISTs and PGLs display phenotypes that differ from their sporadically occurring, more-common counterparts; as a result, it is important to understand the unique features of imaging, treatment, and surveillance in patients with CSS.
Table 6. Comparison of Carney-Stratakis Syndrome, Carney Triad, and Carney Complex
ENLARGE
SyndromeInheritance PatternMean Age at Onset (y)Affected SexAssociated LesionsPathogenic VariantsTumor Behavior
AD = autosomal dominant; GIST = gastrointestinal stromal tumor; F = female; M = male.
Carney-Stratakis syndrome [1,3,4]AD23M, FParaganglioma, stomach epithelioid GISTGermline SDHx pathogenic variants common; no KIT or PDGFRA pathogenic variantsGIST metastasis but protracted course; paraganglioma aggressive
Carney triad [4-6]None<30>95% FLung chondroma, paraganglioma, stomach epithelioid GISTNo KIT or PDGFRA pathogenic variants; rarely, SDHx pathogenic variants (9.5% in one series) [7]GIST metastasis but protracted course
Carney complex [8,9]AD20M, FLentigines, myxomas, schwannoma, thyroid follicular adenomas or carcinoma, primary pigmented nodular adrenocortical disease, pituitary adenomasGermline PRKAR1A pathogenic variantsN/A

Genetics, Inheritance, and Genetic Testing

The tumorigenesis of CSS-associated GISTs appears to involve succinate dehydrogenase deficiency rather than gain-of-function mutation in the KIT or PDGFRA gene, as is seen in the vast majority of GISTs.[10] SDH deficiency is also a characteristic finding of pediatric-type GISTs; CSS-associated GISTs display clinical findings similar to these tumors, including young age at onset (median age, 19 y), specificity to the stomach, multifocality, and resistance to imatinib.[3,11-13] Furthermore, tumor size and mitotic rate do not accurately predict metastatic potential or survival, as SDH-deficient GISTs frequently metastasize to regional lymph nodes, the peritoneal cavity, and the liver; however, long-term survival is common.[6,14]
Refer to the Genetics, Inheritance, and Genetic Testing section in the Familial Pheochromocytoma and PGL Syndrome section of this summary for more information about genetic testing for the genes involved in CSS.

Surveillance

Although the natural history of CSS is poorly understood, experts recommend that ongoing surveillance include the following: close patient follow-up with annual history that focuses on symptoms of anemia and catecholamine excess, physical exam, biochemical analysis with plasma metanephrine level and chromogranin A to detect recurrent PGLs, and cross-sectional imaging. Although many PGLs do not secrete catecholamines, chromogranin A has been found to be elevated in PGLs and may be a useful marker for tumor recurrence. The appropriate screening imaging modality is unknown at this time, but fluorine F 18-fludeoxyglucose positron emission tomography–computed tomography (18F-FDG PET-CT) is highly sensitive at identifying extra-adrenal PGLs and GISTs. Because of the risks of ionizing radiation exposure from CT, some suggest using MRI for annual surveillance.[15,16]

Interventions

Because multiple primary GISTs and PGLs are common with CSS, preoperative imaging is paramount to accurately identify the extent of disease before surgical planning. Most patients will present having already undergone imaging with CT or magnetic resonance imaging (MRI). Both methods have excellent sensitivity for identifying PGLs, but additional functional imaging is recommended because of the diffuse nature of these tumors. 18F-FDG PET-CT is superior to iodine I 123-metaiodobenzylguanidine at identifying SDHx-associated PGLs and, because of the high metabolic activity of GISTs, has excellent sensitivity in identifying them.[15,17] Thus, in patients with SDHx pathogenic variants, including those with CSS, 18F-FDG PET-CT is the preferred functional imaging modality to optimally detect and stage all GISTs and PGLs.[16] Some evidence suggests that 18F-fluoro-L-dihydroxyphenylalanine (18F-FDOPA) PET-CT is superior at identifying the primary PGL, while 18F-FDG PET-CT is superior at identifying metastases.
There are no prospective treatment studies involving patients with CSS; therefore, recommendations are based on limited clinical experience, single case series, and extrapolations from genetically-similar tumors with similar clinical behavior. The mainstay of treatment for CSS-associated GISTs and PGLs is complete surgical resection of the tumor. The timing of the operation correlates with the presentation of the tumor. Surgical resection can be accomplished with laparoscopic or open techniques. For PGLs, vascular reconstruction is uncommon. Although PGLs are commonly present in the paraaortic region, the need for major vascular reconstruction is uncommon. GIST tumors can be resected with wedge resection and primary closure and re-anastomosis. Ensuring negative margins is important, as patients for whom a complete resection is accomplished experience the longest survival.[18] In the rare setting of synchronous disease, combined resection is appropriate if tolerable by the patient. More commonly, tumors develop metachronously, with GISTs arising first; individual resection occurs at the time of diagnosis of each tumor.
A thorough preoperative endoscopy and complete surgical exploration of the stomach are essential, as multiple separate GISTs are frequently encountered. The high frequency of multifocality and the likelihood of tumor recurrence do not justify a prophylactic total gastrectomy because of its substantial associated morbidity. Furthermore, a total gastrectomy is generally only performed when the current disease burden precludes a lesser resection. To this end, gastric wedge resection with gross negative margins is the surgical goal.[19] Sampling of any suspicious nodes at the time of resection is commonly performed. Evidence suggests that locally advanced CSS-associated GISTs demonstrate a rather indolent course;[20] thus, the concern for nodal involvement based on preoperative imaging or abdominal exploration need not deter resection of the primary tumor. While a role for neoadjuvant imatinib in locally advanced adult-type GISTs has been widely described to improve resectability or reduce the burden of resection, it is unlikely to have any effect in locally advanced SDH-deficient GISTs.[21] Evidence suggests that for these tumors, the second-line targeted agents, including sorafenib, sunitinib, dasatinib, and nilotinib, may be beneficial in the adjuvant setting.[22,23] No data support using these agents in the neoadjuvant setting at this time.
Regarding treatment of CSS-associated PGLs, patients are commonly initiated on alpha-blockade preoperatively to minimize perioperative cardiac morbidity and mortality. PGLs typically occur in the para-aortic chain from the urinary bladder and the aortic bifurcation to the superior mediastinum and head and neck. As in the treatment of GISTs, the operative goal is resection of all known disease. Preoperative imaging and intra-operative exploration are essential to achieving this goal. Multiple tumors are common; when disease is present in the bilateral adrenal glands, the surgeon faces the possibility of rendering a patient steroid dependent with a lifelong risk of a fatal Addisonian crisis. In this setting, a surgeon proficient in performing a cortical-sparing adrenalectomy may be consulted.
References
  1. Carney JA, Stratakis CA: Familial paraganglioma and gastric stromal sarcoma: a new syndrome distinct from the Carney triad. Am J Med Genet 108 (2): 132-9, 2002. [PUBMED Abstract]
  2. McWhinney SR, Pasini B, Stratakis CA, et al.: Familial gastrointestinal stromal tumors and germ-line mutations. N Engl J Med 357 (10): 1054-6, 2007. [PUBMED Abstract]
  3. Pasini B, McWhinney SR, Bei T, et al.: Clinical and molecular genetics of patients with the Carney-Stratakis syndrome and germline mutations of the genes coding for the succinate dehydrogenase subunits SDHB, SDHC, and SDHD. Eur J Hum Genet 16 (1): 79-88, 2008. [PUBMED Abstract]
  4. Gaal J, Stratakis CA, Carney JA, et al.: SDHB immunohistochemistry: a useful tool in the diagnosis of Carney-Stratakis and Carney triad gastrointestinal stromal tumors. Mod Pathol 24 (1): 147-51, 2011. [PUBMED Abstract]
  5. Agaimy A, Pelz AF, Corless CL, et al.: Epithelioid gastric stromal tumours of the antrum in young females with the Carney triad: a report of three new cases with mutational analysis and comparative genomic hybridization. Oncol Rep 18 (1): 9-15, 2007. [PUBMED Abstract]
  6. Zhang L, Smyrk TC, Young WF, et al.: Gastric stromal tumors in Carney triad are different clinically, pathologically, and behaviorally from sporadic gastric gastrointestinal stromal tumors: findings in 104 cases. Am J Surg Pathol 34 (1): 53-64, 2010. [PUBMED Abstract]
  7. Boikos SA, Xekouki P, Fumagalli E, et al.: Carney triad can be (rarely) associated with germline succinate dehydrogenase defects. Eur J Hum Genet 24 (4): 569-73, 2016. [PUBMED Abstract]
  8. Boikos SA, Stratakis CA: Carney complex: pathology and molecular genetics. Neuroendocrinology 83 (3-4): 189-99, 2006. [PUBMED Abstract]
  9. Correa R, Salpea P, Stratakis CA: Carney complex: an update. Eur J Endocrinol 173 (4): M85-97, 2015. [PUBMED Abstract]
  10. Hensen EF, Bayley JP: Recent advances in the genetics of SDH-related paraganglioma and pheochromocytoma. Fam Cancer 10 (2): 355-63, 2011. [PUBMED Abstract]
  11. Agaram NP, Laquaglia MP, Ustun B, et al.: Molecular characterization of pediatric gastrointestinal stromal tumors. Clin Cancer Res 14 (10): 3204-15, 2008. [PUBMED Abstract]
  12. Miettinen M, Wang ZF, Sarlomo-Rikala M, et al.: Succinate dehydrogenase-deficient GISTs: a clinicopathologic, immunohistochemical, and molecular genetic study of 66 gastric GISTs with predilection to young age. Am J Surg Pathol 35 (11): 1712-21, 2011. [PUBMED Abstract]
  13. Sawhney SA, Chapman AD, Carney JA, et al.: Incomplete Carney triad--a review of two cases. QJM 102 (9): 649-53, 2009. [PUBMED Abstract]
  14. Rege TA, Wagner AJ, Corless CL, et al.: "Pediatric-type" gastrointestinal stromal tumors in adults: distinctive histology predicts genotype and clinical behavior. Am J Surg Pathol 35 (4): 495-504, 2011. [PUBMED Abstract]
  15. Ayala-Ramirez M, Callender GG, Kupferman ME, et al.: Paraganglioma syndrome type 1 in a patient with Carney-Stratakis syndrome. Nat Rev Endocrinol 6 (2): 110-5, 2010. [PUBMED Abstract]
  16. Timmers HJ, Kozupa A, Chen CC, et al.: Superiority of fluorodeoxyglucose positron emission tomography to other functional imaging techniques in the evaluation of metastatic SDHB-associated pheochromocytoma and paraganglioma. J Clin Oncol 25 (16): 2262-9, 2007. [PUBMED Abstract]
  17. Timmers HJ, Chen CC, Carrasquillo JA, et al.: Comparison of 18F-fluoro-L-DOPA, 18F-fluoro-deoxyglucose, and 18F-fluorodopamine PET and 123I-MIBG scintigraphy in the localization of pheochromocytoma and paraganglioma. J Clin Endocrinol Metab 94 (12): 4757-67, 2009. [PUBMED Abstract]
  18. Abadin SS, Ayala-Ramirez M, Jimenez C, et al.: Impact of surgical resection for subdiaphragmatic paragangliomas. World J Surg 38 (3): 733-41, 2014. [PUBMED Abstract]
  19. Demetri GD, Benjamin RS, Blanke CD, et al.: NCCN Task Force report: management of patients with gastrointestinal stromal tumor (GIST)--update of the NCCN clinical practice guidelines. J Natl Compr Canc Netw 5 (Suppl 2): S1-29; quiz S30, 2007. [PUBMED Abstract]
  20. Maki RG, Blay JY, Demetri GD, et al.: Key Issues in the Clinical Management of Gastrointestinal Stromal Tumors: An Expert Discussion. Oncologist 20 (7): 823-30, 2015. [PUBMED Abstract]
  21. Ganjoo KN, Villalobos VM, Kamaya A, et al.: A multicenter phase II study of pazopanib in patients with advanced gastrointestinal stromal tumors (GIST) following failure of at least imatinib and sunitinib. Ann Oncol 25 (1): 236-40, 2014. [PUBMED Abstract]
  22. Gill AJ, Chou A, Vilain R, et al.: Immunohistochemistry for SDHB divides gastrointestinal stromal tumors (GISTs) into 2 distinct types. Am J Surg Pathol 34 (5): 636-44, 2010. [PUBMED Abstract]
  23. Janeway KA, Albritton KH, Van Den Abbeele AD, et al.: Sunitinib treatment in pediatric patients with advanced GIST following failure of imatinib. Pediatr Blood Cancer 52 (7): 767-71, 2009. [PUBMED Abstract]

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