Imaging of the Pediatric Thymus and Thymic Disorders

Part of the Medical Radiology book series (MEDRAD)


Imaging of the thymus can prove challenging for the radiologist. The purpose of this chapter is to provide a broad overview of the thymus, its role in normal physiology and pathologic processes. After a brief discussion of the history of the thymus, the embryology, anatomy, and histology of the thymus are reviewed. The normal appearance of the thymus using the various imaging modalities available to the radiologist is then discussed, followed by an overview of congenital thymic variants and benign pathologies involving the thymus, including thymolipoma, thymoma, and thymic rebound. The chapter concludes with a summary of thymic malignancies, with a primary focus on leukemia and lymphoma.


Standardize Uptake Value Hodgkin Lymphoma Superior Vena Cava Anaplastic Large Cell Lymphoma Mediastinal Mass 


  1. Abramson SJ, Price AP (2008) Imaging of pediatric lymphomas. Radiol Clin North Am 46:313–338, ixGoogle Scholar
  2. Ackman JB, Wu CC (2011) MRI of the thymus. Am J Roentgenol 197:W15–W20CrossRefGoogle Scholar
  3. Adam EJ, Ignotus PI (1993) Sonography of the thymus in healthy children: frequency of visualization, size, and appearance. Am J Roentgenol 161:153–155CrossRefGoogle Scholar
  4. Anastasiadis K, Ratnatunga C (2007) The thymus gland: diagnosis and surgical management. Springer, BerlinGoogle Scholar
  5. Arthur R (2000) Interpretation of the paediatric chest X-ray. Paediatr Respir Rev 1:41–50PubMedGoogle Scholar
  6. Attias D, Hodgson D, Weitzman S (2009) Primary mediastinal B-cell lymphoma in the pediatric patient: can a rational approach to therapy be based on adult studies? Pediatr Blood Cancer 52:566–570PubMedCrossRefGoogle Scholar
  7. Bae YA, Lee KS (2010) Cross-sectional evaluation of thoracic lymphoma. Thorac Surg Clin 20:175–186PubMedCrossRefGoogle Scholar
  8. Balcom RJ, Hakanson DO, Werner A et al (1985) Massive thymic hyperplasia in an infant with Beckwith-Wiedemann syndrome. Arch Pathol Lab Med 109:153–155PubMedGoogle Scholar
  9. Bale PM, Sotelo-Avila C (1993) Maldescent of the thymus: 34 necropsy and 10 surgical cases, including 7 thymuses medial to the mandible. Pediatr Pathol 13:181–190PubMedCrossRefGoogle Scholar
  10. Buckley RH (2006) Primary immunodeficiency or not? Making the correct diagnosis. J Allergy Clin Immunol 117:756–758PubMedCrossRefGoogle Scholar
  11. Connolly LP, Connolly SA (2003) Thymic uptake of radiopharmaceuticals. Clin Nucl Med 28:648–651PubMedGoogle Scholar
  12. Costa NS, Laor T, Donnelly LF (2010) Superior cervical extension of the thymus: a normal finding that should not be mistaken for a mass. Radiology 256:238–242PubMedCrossRefGoogle Scholar
  13. Cronin CG, Swords R, Truong MT et al (2010) Clinical utility of PET/CT in lymphoma. Am J Roentgenol 194:W91–W103CrossRefGoogle Scholar
  14. Even-Sapir E, Israel O (2003) Gallium-67 scintigraphy: a cornerstone in functional imaging of lymphoma. Eur J Nucl Med Mol Imaging 30(Suppl 1):S65–S81PubMedGoogle Scholar
  15. Friedmann AM, Wolfson JA, Hudson MM et al (2013) Relapse after treatment of pediatric Hodgkin lymphoma: outcome and role of surveillance after end of therapy. Pediatr Blood Cancer 60:1458–1463PubMedCrossRefGoogle Scholar
  16. Gartner LA, Voorhess ML (1993) Adrenocorticotropic hormone—producing thymic carcinoid in a teenager. Cancer 71:106–111PubMedCrossRefGoogle Scholar
  17. Gawande RS, Khurana A, Messing S et al (2012) Differentiation of normal thymus from anterior mediastinal lymphoma and lymphoma recurrence at pediatric PET/CT. Radiology 262:613–622PubMedCrossRefGoogle Scholar
  18. Guillerman RP, Voss SD, Parker BR (2011) Leukemia and lymphoma. Radiol Clin North Am 49:767–797, viiGoogle Scholar
  19. Hegde KV, Suneetha P, Pradeep PV et al (2012) Asymptomatic thymic cyst appearing in the neck on valsalva: unusual presentation of a rare disease. J Clin Imaging Sci 2:11PubMedCentralPubMedCrossRefGoogle Scholar
  20. Henkelman RM, Hardy PA, Bishop JE et al (1992) Why fat is bright in RARE and fast spin-echo imaging. J Magn Reson Imaging 2:533–540PubMedGoogle Scholar
  21. Hodgson DC, Hudson MM, Constine LS (2007) Pediatric hodgkin lymphoma: maximizing efficacy and minimizing toxicity. Semin Radiat Oncol 17:230–242PubMedCrossRefGoogle Scholar
  22. Hutchinson CB, Wang E (2011) Primary mediastinal (thymic) large B-cell lymphoma: a short review with brief discussion of mediastinal gray zone lymphoma. Arch Pathol Lab Med 135:394–398PubMedGoogle Scholar
  23. Inaoka T, Takahashi K, Mineta M et al (2007) Thymic hyperplasia and thymus gland tumors: differentiation with chemical shift MR imaging. Radiology 243:869–876PubMedCrossRefGoogle Scholar
  24. Jacobs MT, Frush DP, Donnelly LF (1999) The right place at the wrong time: historical perspective of the relation of the thymus gland and pediatric radiology. Radiology 210:11–16PubMedCrossRefGoogle Scholar
  25. Johnson PW, Davies AJ (2008) Primary mediastinal B-cell lymphoma. Hematol Am Soc Hematol Educ Program 2008:349–358Google Scholar
  26. Kaufman MR, Smith S, Rothschild MA et al (2001) Thymopharyngeal duct cyst: an unusual variant of cervical thymic anomalies. Arch Otolaryngol Head Neck Surg 127:1357–1360PubMedCrossRefGoogle Scholar
  27. Kelly KM, Hodgson D, Appel B et al (2013) Children’s Oncology Group’s 2013 blueprint for research: Hodgkin lymphoma. Pediatr Blood Cancer 60:972–978PubMedCrossRefGoogle Scholar
  28. Kim OH, Kim WS, Kim MJ et al (2000) US in the diagnosis of pediatric chest diseases. Radiographics 20:653–671PubMedCrossRefGoogle Scholar
  29. Kluge R, Kurch L, Montravers F et al (2013) FDG PET/CT in children and adolescents with lymphoma. Pediatr Radiol 43:406–417PubMedCrossRefGoogle Scholar
  30. Kontny HU, Sleasman JW, Kingma DW et al (1997) Multilocular thymic cysts in children with human immunodeficiency virus infection: clinical and pathologic aspects. J Pediatr 131:264–270PubMedCrossRefGoogle Scholar
  31. MacDonald K, Mackenzie S (2009) What happens to the thymus in children who have undergone a median sternotomy? Pediatr Radiol 39:616–621PubMedCrossRefGoogle Scholar
  32. Martelli M, Ferreri AJ, Johnson P (2008) Primary mediastinal large B-cell lymphoma. Crit Rev Oncol Hematol 68:256–263PubMedCrossRefGoogle Scholar
  33. Mizuno T, Hashimoto T, Masaoka A et al (1997) Thymic follicular hyperplasia manifested as an anterior mediastinal mass. Surg Today 27:275–277PubMedCrossRefGoogle Scholar
  34. Molina PL, Siegel MJ, Glazer HS (1990) Thymic masses on MR imaging. Am J Roentgenol 155:495–500CrossRefGoogle Scholar
  35. Mong A, Epelman M, Darge K (2012) Ultrasound of the pediatric chest. Pediatr Radiol 42:1287–1297PubMedCrossRefGoogle Scholar
  36. Mortelmans A, Hermans R (2005) Thymopharyngeal duct cyst. JBR-BTR 88:99PubMedGoogle Scholar
  37. Nasseri F, Eftekhari F (2010) Clinical and radiologic review of the normal and abnormal thymus: pearls and pitfalls. Radiographics 30:413–428PubMedCrossRefGoogle Scholar
  38. Newman B (2011) Ultrasound body applications in children. Pediatr Radiol 41(Suppl 2):555–561PubMedCrossRefGoogle Scholar
  39. Park CM, Goo JM, Lee HJ et al (2009) Tumors in the tracheobronchial tree: CT and FDG PET features. Radiographics 29:55–71PubMedCrossRefGoogle Scholar
  40. Petroze R, McGahren ED: Pediatric chest II (2012) Benign tumors and cysts. Surg Clin North Am 92:645–658, ixGoogle Scholar
  41. Rathore N, Eissa HM, Margolin JF et al (2012) Pediatric Hodgkin lymphoma: are we over-scanning our patients? Pediatr Hematol Oncol 29:415–423PubMedCentralPubMedCrossRefGoogle Scholar
  42. Restrepo CS, Pandit M, Rojas IC et al (2005) Imaging findings of expansile lesions of the thymus. Curr Probl Diagn Radiol 34:22–34PubMedCrossRefGoogle Scholar
  43. Ries LAG, Smith MA, Gurney JG, Linet M, Tamra T, Young JL (1999) Cancer Incidence and Survival among Children and Adolescents: United States SEER Program 1975-1995. In: Bunin GR (ed) National Cancer Institute SEER Program. No. 99-4649, Bethesda, MDGoogle Scholar
  44. Safieddine N, Keshavjee S (2011) Anatomy of the thymus gland. Thorac Surg Clin 21:191–195, viiiGoogle Scholar
  45. Sharma P, Singhal A, Kumar A et al (2013) Evaluation of thymic tumors with 18F-FDG PET-CT: a pictorial review. Acta Radiol 54:14–21PubMedCrossRefGoogle Scholar
  46. Shepherd SF, A’Hern RP, Pinkerton CR (1995) Childhood T-cell lymphoblastic lymphoma—does early resolution of mediastinal mass predict for final outcome? The United Kingdom Children’s Cancer Study Group (UKCCSG). Br J Cancer 72:752–756PubMedCentralPubMedCrossRefGoogle Scholar
  47. Siegel MJ, Glazer HS, Wiener JI et al (1989) Normal and abnormal thymus in childhood: MR imaging. Radiology 172:367–371PubMedCrossRefGoogle Scholar
  48. Sklair-Levy M, Agid R, Sella T et al (2000) Age-related changes in CT attenuation of the thymus in children. Pediatr Radiol 30:566–569PubMedCrossRefGoogle Scholar
  49. Tateishi U, Muller NL, Johkoh T et al (2004) Primary mediastinal lymphoma: characteristic features of the various histological subtypes on CT. J Comput Assist Tomogr 28:782–789PubMedCrossRefGoogle Scholar
  50. Termuhlen AM, Smith LM, Perkins SL et al (2013) Disseminated lymphoblastic lymphoma in children and adolescents: results of the COG A5971 trial: a report from the children’s oncology group. Br J Haematol 162:792–801PubMedCrossRefGoogle Scholar
  51. Tunkel DE, Erozan YS, Weir EG (2001) Ectopic cervical thymic tissue: diagnosis by fine needle aspiration. Arch Pathol Lab Med 125:278–281PubMedGoogle Scholar
  52. Varga I, Pospisilova V, Jablonska-Mestanova V et al (2011) The thymus: picture review of human thymus prenatal development. Bratisl Lek Listy 112:368–376PubMedGoogle Scholar
  53. Voss SD, Chen L, Constine LS, Chauvenet A, Fitzgerald TJ, Kaste SC, Slovis T, and Schwartz CL (2012) Surveillance computed tomography imaging and detection of relapse in intermediate- and advanced-stage pediatric Hodgkin's lymphoma: a report from the Children's Oncology Group. J Clin Oncol 30(21):2635–2640Google Scholar
  54. Voss SD (2013) Surveillance imaging in pediatric hodgkin lymphoma. Curr Hematol Malig Rep 8:218–225Google Scholar
  55. Yaris N, Nas Y, Cobanoglu U et al (2006) Thymic carcinoma in children. Pediatr Blood Cancer 47:224–227PubMedCrossRefGoogle Scholar
  56. Yin EZ, Frush DP, Donnelly LF et al (2001) Primary immunodeficiency disorders in pediatric patients: clinical features and imaging findings. Am J Roentgenol 176:1541–1552CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Department of RadiologyBoston Children’s HospitalBostonUSA

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