Diagnostic Imaging for Thoracic Surgery pp 223-234 | Cite as
Imaging and Staging of Thymic Tumors
Abstract
The thymus is a primary lymphoid organ located in the upper prevascular mediastinum. A number of masses arise in relation to the thymus. Accurate knowledge of anatomy and imaging features is essential for the differentiation between non-tumoral thymic pathology and malignant thymic tumors. In general, a benign hyperplasia of the thymus occurs in children and young adults, while in adults thymoma is the most common tumor. Furthermore imaging is of great importance in the preoperative staging and (oncological) follow-up. Computed tomography (CT) is the imaging modality of choice to assess the mediastinal structures, including the thymus. Medical imaging is essential to further characterize those lesions that warrant further workup. Surgery is the gold standard for the treatment of thymoma with the aim of complete resection. We provide an overview of thymic masses with typically imaging features: thymic hyperplasia, thymic cyst, thymolipoma, thymoma, thymic carcinoma, and thymic carcinoid. Lymphoma will be discussed in Chapter 15: Imaging of Non-thymic Mediastinal Tumors.
Keywords
Prevascular mediastinum Thymus Thymic hyperplasia Thymic cyst Thymolipoma Thymoma Thymic carcinoma Thymic carcinoid Staging thymic epithelial tumors ImagingReferences
- 1.Rezzani R, Nardo L, Favero G, Peroni M, Rodella LF. Thymus and aging: morphological, radiological, and functional overview. Age (Omaha). 2014;36(1):313–51. https://doi.org/10.1007/s11357-013-9564-5.CrossRefGoogle Scholar
- 2.Suster S, Rosai J. Histology of the normal thymus. Am J Surg Pathol. 1990;14(3):284–303. http://www.ncbi.nlm.nih.gov/pubmed/2407143.
- 3.Peters R, Peters O, Braak S, Verschakelen J. Pictorial essay. Pathology of the thymus on CT-imaging. J Belgian Soc Radiol. 2012;95(5):281. https://doi.org/10.5334/jbr-btr.648.CrossRefGoogle Scholar
- 4.Lele SM, Lele MS, Anderson VM. The thymus in infancy and childhood. Embryologic, anatomic, and pathologic considerations. Chest Surg Clin N Am. 2001;11(2):233–53. http://www.ncbi.nlm.nih.gov/pubmed/11413754.
- 5.Safieddine N, Keshavjee S. Anatomy of the thymus gland. Thorac Surg Clin. 2011;21(2):191–5. https://doi.org/10.1016/j.thorsurg.2010.12.011.CrossRefPubMedGoogle Scholar
- 6.Carter BW, Benveniste MF, Madan R, et al. ITMIG Classification of mediastinal compartments and multidisciplinary approach to mediastinal masses. Radiographics. 2017;37(2). https://doi.org/10.1148/rg.2017160095.
- 7.Nasseri F, Eftekhari F. Clinical and radiologic review of the normal and abnormal thymus: pearls and pitfalls. Radiographics. 2010;30(2):413–28. https://doi.org/10.1148/rg.302095131.CrossRefPubMedGoogle Scholar
- 8.Walter E, Willich E, Webb WR. The thymus : diagnostic imaging, functions, and pathologic anatomy. Berlin, Heidelberg: Springer; 1992.CrossRefGoogle Scholar
- 9.TAUSEND ME, STERN WZ. Thymic patterns in the newborn. Am J Roentgenol Radium Ther Nucl Med. 1965;95:125–30. http://www.ncbi.nlm.nih.gov/pubmed/14344350.
- 10.Mulvey RB. The Thymic “Wave” Sign. Radiology. 1963;81(5):834–8. https://doi.org/10.1148/81.5.834.CrossRefPubMedGoogle Scholar
- 11.Takahashi K, Al-Janabi NJ. Computed tomography and magnetic resonance imaging of mediastinal tumors. J Magn Reson Imaging. 2010;32(6):1325–39. https://doi.org/10.1002/jmri.22377.CrossRefPubMedGoogle Scholar
- 12.Lee YM, Koh MT, Omar A, Majid A. Hyperplasia of thymic gland. Singapore Med J. 1996;37(3):288–90. http://www.ncbi.nlm.nih.gov/pubmed/8942232.
- 13.Hansell DM. Imaging of Diseases of the Chest: Mosby; 2010.Google Scholar
- 14.Chertoff J, Barth RA, Dickerman JD. Rebound thymic hyperplasia five years after chemotherapy for Wilms’ tumor. Pediatr Radiol. 1991;21(8):596–7. http://www.ncbi.nlm.nih.gov/pubmed/1667681.
- 15.Nishino M, Ashiku SK, Kocher ON, Thurer RL, Boiselle PM, Hatabu H. The Thymus: A Comprehensive Review. Radiographics. 2006;26(2):335–48. https://doi.org/10.1148/rg.262045213.CrossRefPubMedGoogle Scholar
- 16.Araki T, Sholl LM, Gerbaudo VH, Hatabu H, Nishino M. Imaging Characteristics of Pathologically Proven Thymic Hyperplasia: Identifying Features That Can Differentiate True From Lymphoid Hyperplasia. Am J Roentgenol. 2014;202(3):471–8. https://doi.org/10.2214/AJR.13.11210.CrossRefGoogle Scholar
- 17.Priola AM, Priola SM. Imaging of thymus in myasthenia gravis: From thymic hyperplasia to thymic tumor. Clin Radiol. 2014;69(5):e230–45. https://doi.org/10.1016/j.crad.2014.01.005.CrossRefPubMedGoogle Scholar
- 18.Brown LR, Aughenbaugh GL. Masses of the anterior mediastinum: CT and MR imaging. AJR Am J Roentgenol. 1991;157(6):1171–80. https://doi.org/10.2214/ajr.157.6.1950860.CrossRefPubMedGoogle Scholar
- 19.Kornstein MJ, DeBlois GG. Pathology of the thymus and mediastinum. W.B. Saunders; 1995.Google Scholar
- 20.Santana L, Givica A, Camacho C. Best Cases from the AFIP. Radiographics. 2002;22(Suppl 1):S95–S102. https://doi.org/10.1148/radiographics.22.suppl_1.g02oc12s95.CrossRefPubMedGoogle Scholar
- 21.Lewis JE, Wick MR, Scheithauer BW, Bernatz PE, Taylor WF. Thymoma. A clinicopathologic review. Cancer. 1987;60(11):2727–43. http://www.ncbi.nlm.nih.gov/pubmed/3677008.
- 22.Lee H-S, Kim ST, Lee J, et al. A single institutional experience of thymic epithelial tumours over 11 years: clinical features and outcome and implications for future management. Br J Cancer. 2007;97(1):22–8. https://doi.org/10.1038/sj.bjc.6603833.CrossRefPubMedPubMedCentralGoogle Scholar
- 23.Masaoka A, Monden Y, Nakahara K, Tanioka T. Follow-up study of thymomas with special reference to their clinical stages. Cancer. 1981;48(11):2485–92. http://www.ncbi.nlm.nih.gov/pubmed/7296496.
- 24.Koga K, Matsuno Y, Noguchi M, et al. A review of 79 thymomas: modification of staging system and reappraisal of conventional division into invasive and non-invasive thymoma. Pathol Int. 1994;44(5):359–67. http://www.ncbi.nlm.nih.gov/pubmed/8044305.
- 25.Marx A, Ströbel P, Badve SS, et al. ITMIG Consensus Statement on the Use of the WHO Histological Classification of Thymoma and Thymic Carcinoma: Refined Definitions, Histological Criteria, and Reporting. J Thorac Oncol. 2014;9(5):596–611. https://doi.org/10.1097/JTO.0000000000000154.CrossRefPubMedGoogle Scholar
- 26.Rosai J, Sobin LH. Histological typing of tumours of the thymus. Berlin, Heidelberg: Springer; 1999. https://doi.org/10.1007/978-3-642-60157-6.CrossRefGoogle Scholar
- 27.Okumura M, Miyoshi S, Fujii Y, et al. Clinical and functional significance of WHO classification on human thymic epithelial neoplasms: a study of 146 consecutive tumors. Am J Surg Pathol. 2001;25(1):103–10. http://www.ncbi.nlm.nih.gov/pubmed/11145244.
- 28.Kondo K, Monden Y. Lymphogenous and hematogenous metastasis of thymic epithelial tumors. Ann Thorac Surg. 2003;76(6):1859–64. https://www.ncbi.nlm.nih.gov/pubmed/14667600CrossRefPubMedGoogle Scholar
- 29.Kondo K. Tumor-Node Metastasis Staging System for Thymic Epithelial Tumors. J Thorac Oncol. 2010;5(10):S352–6. https://doi.org/10.1097/JTO.0b013e3181f20f3b.CrossRefPubMedGoogle Scholar
- 30.Benveniste MFK, Rosado-de-Christenson ML, Sabloff BS, Moran CA, Swisher SG, Marom EM. Role of Imaging in the Diagnosis, Staging, and Treatment of Thymoma. Radiographics. 2011;31(7):1847–61. https://doi.org/10.1148/rg.317115505.CrossRefPubMedGoogle Scholar
- 31.Tomaszek S, Wigle DA, Keshavjee S, Fischer S. Thymomas: review of current clinical practice. Ann Thorac Surg. 2009;87(6):1973–80. https://doi.org/10.1016/j.athoracsur.2008.12.095.CrossRefPubMedPubMedCentralGoogle Scholar
- 32.Safieddine N, Liu G, Cuningham K, et al. Prognostic factors for cure, recurrence and long-term survival after surgical resection of thymoma. J Thorac Oncol. 2014;9(7):1018–22. https://doi.org/10.1097/JTO.0000000000000215.CrossRefPubMedGoogle Scholar
- 33.Marom EM. Advances in thymoma imaging. J Thorac Imaging. 2013;28(2):69–83. https://doi.org/10.1097/RTI.0b013e31828609a0.CrossRefPubMedGoogle Scholar
- 34.Lee JD, Choe KO, Kim SJ, Kim GE, Im JG, Lee JT. CT findings in primary thymic carcinoma. J Comput Assist Tomogr. 15(3):429–33. http://www.ncbi.nlm.nih.gov/pubmed/2026804.
- 35.Chaer R, Massad MG, Evans A, Snow NJ, Geha AS. Primary neuroendocrine tumors of the thymus. Ann Thorac Surg. 2002;74(5):1733–40. http://www.ncbi.nlm.nih.gov/pubmed/12440652.
- 36.Goto K, Kodama T, Matsuno Y, et al. Clinicopathologic and DNA cytometric analysis of carcinoid tumors of the thymus. Mod Pathol. 2001;14(10):985–94. https://doi.org/10.1038/modpathol.3880423.CrossRefPubMedGoogle Scholar
- 37.Gaude GS, Hattiholi V, Malur PR, Hattiholi J. Primary neuroendocrine carcinoma of the thymus. Niger Med J. 2013;54(1):68–71. https://doi.org/10.4103/0300-1652.108904.CrossRefPubMedPubMedCentralGoogle Scholar
- 38.Ahn S, Lee JJ, Ha SY, Sung CO, Kim J, Han J. Clinicopathological analysis of 21 thymic neuroendocrine tumors. Korean J Pathol. 2012;46(3):221–5. https://doi.org/10.4132/KoreanJPathol.2012.46.3.221.CrossRefPubMedPubMedCentralGoogle Scholar
- 39.Moran MDCA, Suster MDS. Neuroendocrine Carcinomas (Carcinoid Tumor) of the Thymus. Am J Clin Pathol. 2000;114(1):100–10. https://doi.org/10.1309/3PDN-PMT5-EQTM-H0CD.CrossRefPubMedGoogle Scholar
- 40.Teh BT, McArdle J, Chan SP, et al. Clinicopathologic studies of thymic carcinoids in multiple endocrine neoplasia type 1. Medicine (Baltimore). 1997;76(1):21–9. http://www.ncbi.nlm.nih.gov/pubmed/9064485.
- 41.Gibril F, Chen Y-J, Schrump DS, et al. Prospective Study of Thymic Carcinoids in Patients with Multiple Endocrine Neoplasia Type 1. J Clin Endocrinol Metab. 2003;88(3):1066–81. https://doi.org/10.1210/jc.2002-021314.CrossRefPubMedGoogle Scholar
- 42.Venkatesh S, Samaan NA. Carcinoid tumors of the thymus. West J Med. 1990;152(1):72–4. http://www.ncbi.nlm.nih.gov/pubmed/2309479.
- 43.Kondo K, Van Schil P, Detterbeck FC, et al. The IASLC/ITMIG Thymic Epithelial Tumors Staging Project: Proposals for the N and M Components for the Forthcoming (8th) Edition of the TNM Classification of Malignant Tumors. J Thorac Oncol. 2014;9(9):S81–7. https://doi.org/10.1097/JTO.0000000000000291.CrossRefPubMedGoogle Scholar
- 44.Nicholson AG, Detterbeck FC, Marino M, et al. The IASLC/ITMIG Thymic Epithelial Tumors Staging Project: Proposals for the T component for the Forthcoming (8th) Edition of the TNM Classification of Malignant Tumors. J Thorac Oncol. 2014;9(9):S73–80. https://doi.org/10.1097/JTO.0000000000000303.CrossRefPubMedGoogle Scholar
- 45.Detterbeck FC, Stratton K, Giroux D, et al. The IASLC/ITMIG Thymic Epithelial Tumors Staging Project: proposal for an evidence-based stage classification system for the forthcoming (8th) edition of the TNM Classification of Malignant Tumors. J Thorac Oncol. 2014;9(9):S65–72. https://doi.org/10.1097/JTO.0000000000000290.CrossRefPubMedGoogle Scholar
- 46.Bhora FY, Chen DJ, Detterbeck FC, et al. The ITMIG/IASLC Thymic Epithelial Tumors Staging Project: a proposed lymph node map for thymic epithelial tumors in the forthcoming 8th edition of the TNM Classification of Malignant Tumors. J Thorac Oncol. 2014;9(9):S88–96. https://doi.org/10.1097/JTO.0000000000000293.CrossRefPubMedGoogle Scholar