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{{Thymoma}}
{{Thymoma}}
{{CMG}} {{AE}} [[User:K.Nouman|Khuram Nouman, M.D. [2]]]  
{{CMG}} {{shyam}} {{AE}} [[User:K.Nouman|Khuram Nouman, M.D. [2]]]  
== Overview ==
== Overview ==
Thymoma can be largely diagnosed by using radiological techniques.
Thymoma can be largely [[Diagnosis|diagnosed]] by using [[Radiology|radiological]] techniques.


== Diagnostic Study of Choice ==
== Diagnostic Study of Choice ==
Investigations:
===Study of Choice===
* Posterior-anterior (PA) and lateral [[Chest X-ray|X-ray of the chest]] are helpful in diagnosing most of thymomas.
*[[Anatomical terms of location|Posterior]]-[[Anatomical terms of location|anterior]] (PA) and [[lateral]] [[Chest X-ray|x-ray of the chest]] are helpful in [[Diagnosis|diagnosing]] most of the thymomas.


* Among the patients who present with clinical signs of [[myasthenia gravis]] (MG), the [[Computed tomography|CT Scan]] is the test of choice for the diagnosis of Thymoma.
* Among the [[Patient|patients]] who present with [[clinical]] signs of [[myasthenia gravis|myasthenia gravis (MG)]], [[Computed tomography|CT scan]] is the test of choice for the [[diagnosis]] of thymoma.
* [[Computed tomography|CT Scan]] with IV contrast and magnetic resonance imaging are helpful in determining the vascularity of the thymoma and helps in safe surgical removal of large tumors.
* [[Computed tomography|CT scan]] with [[IV]] [[contrast]] and [[Magnetic resonance imaging|MRI]] are helpful in determining the [[vascularity]] of the thymoma and helps in safe [[Surgery|surgical]] removal of large [[Tumor|tumors]].
* PET Scan is very valuable in diagnosing the cases of invasive [[malignant]] thymoma.
*[[Positron emission tomography|PET scan]] is very valuable in [[Diagnosis|diagnosing]] the cases of [[Invasive (medical)|invasive]] [[malignant]] thymoma.<ref name="pmid26273398">{{cite journal| author=Scagliori E, Evangelista L, Panunzio A, Calabrese F, Nannini N, Polverosi R et al.| title=Conflicting or complementary role of computed tomography (CT) and positron emission tomography (PET)/CT in the assessment of thymic cancer and thymoma: our experience and literature review. | journal=Thorac Cancer | year= 2015 | volume= 6 | issue= 4 | pages= 433-42 | pmid=26273398 | doi=10.1111/1759-7714.12197 | pmc=4511321 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=26273398  }} </ref>
* Thallium 201 single photon emission computed tomography is useful to distinguish normal thymic tissue from hyperplastic tissue or thymoma  
* Thallium 201 single photon emission [[computed tomography]] is useful to distinguish normal [[Thymus|thymic]] [[Tissue (biology)|tissue]] from [[Hyperplasia|hyperplastic]] [[Tissue (biology)|tissue]] or thymoma
* Ultrasonically guided core needle biopsy is used to obtain larger tissue specimens for histological examination. Annessi and colleagues were able to diagnose thymoma in all patients that had undergone anterior mediastinal core [[needle biopsy]] by ultrasonic guidance with a [[sensitivity]] and [[specificity]] of 100%.   
*[[Medical ultrasonography|Ultrasonically]] guided core [[Needle aspiration biopsy|needle biopsy]] is used to obtain larger [[Tissue (biology)|tissue]] specimens for [[histological]] [[examination]].  
*Annessi and colleagues were able to [[Diagnosis|diagnose]] thymoma in all [[Patient|patients]] who had undergone [[Anterior mediastinum|anterior mediastinal]] core [[needle biopsy]] by [[Medical ultrasonography|ultrasonic]] guidance with a [[sensitivity]] and [[specificity]] of 100%.
 
===Staging===
* The thymic epithelial tumor [[Cancer staging|staging]] system was initially proposed by Bergh and his colleagues in 1978, modified by Wilkins and Castleman in 1979, and further developed by Masaoka et al. in 1981.<ref name="Wilkins-1979">{{Cite journal  | last1 = Wilkins | first1 = EW. | last2 = Castleman | first2 = B. | title = Thymoma: a continuing survey at the Massachusetts General Hospital. | journal = Ann Thorac Surg | volume = 28 | issue = 3 | pages = 252-6 | month = Sep | year = 1979 | doi =  | PMID = 485626 }}</ref><ref name="Bergh-1978">{{Cite journal  | last1 = Bergh | first1 = NP. | last2 = Gatzinsky | first2 = P. | last3 = Larsson | first3 = S. | last4 = Lundin | first4 = P. | last5 = Ridell | first5 = B. | title = Tumors of the thymus and thymic region: I. Clinicopathological studies on thymomas. | journal = Ann Thorac Surg | volume = 25 | issue = 2 | pages = 91-8 | month = Feb | year = 1978 | doi =  | PMID = 626543 }}</ref><ref name="Masaoka-1981">{{Cite journal  | last1 = Masaoka | first1 = A. | last2 = Monden | first2 = Y. | last3 = Nakahara | first3 = K. | last4 = Tanioka | first4 = T. | title = Follow-up study of thymomas with special reference to their clinical stages. | journal = Cancer | volume = 48 | issue = 11 | pages = 2485-92 | month = Dec | year = 1981 | doi =  | PMID = 7296496 }}</ref><ref name="Kondo-2005">{{Cite journal  | last1 = Kondo | first1 = K. | title = Invited commentary. | journal = Ann Thorac Surg | volume = 80 | issue = 6 | pages = 2000-1 | month = Dec | year = 2005 | doi = 10.1016/j.athoracsur.2005.08.053 | PMID = 16305832 }}</ref>
* Modified Masaoka staging grouped with [[TNM classification]] is the most widely adopted system for thymic epithelial tumors currently in use.
 
====Modified Masaoka Clinical Staging of Thymoma====
 
{| style="border: 0px; font-size: 90%; margin: 3px;" align="center"
|+ <SMALL>'''''Modified Masaoka Clinical Staging of Thymoma (1994)'''''<ref name="Masaoka-1994">{{Cite journal  | last1 = Masaoka | first1 = A. | last2 = Yamakawa | first2 = Y. | last3 = Niwa | first3 = H. | last4 = Fukai | first4 = I. | last5 = Saito | first5 = Y. | last6 = Tokudome | first6 = S. | last7 = Nakahara | first7 = K. | last8 = Fujii | first8 = Y. | title = Thymectomy and malignancy. | journal = Eur J Cardiothorac Surg | volume = 8 | issue = 5 | pages = 251-3 | month =  | year = 1994 | doi =  | PMID = 8043287 }}</ref></SMALL>
! style="background: #4479BA; color:#FFF;" | '''Stage'''
! style="background: #4479BA; color:#FFF;" | '''Description'''
|-
| style="background: #F0F0F0;" align="center" | '''I'''
| style="background: #F0F0F0;" |
* [[Macroscopic|Macroscopically]] and [[Microscopic|microscopically]] completely encapsulated
|-
| style="background: #F0F0F0;" align="center" | '''II'''
| style="background: #F0F0F0;" |
* '''A:''' [[Microscopic]] transcapsular [[Invasive (medical)|invasion]]
* '''B:''' [[Macroscopic]] [[Invasive (medical)|invasion]] into surrounding [[Fat tissue|fatty tissue]] or [[Gross|grossly]] adherent to but not through <BR> [[mediastinal pleura]] or [[pericardium]]
|-
| style="background: #F0F0F0;" align="center" | '''III'''
| style="background: #F0F0F0;" |
* [[Macroscopic]] [[Invasive (medical)|invasion]] into neighboring [[organs]] ([[pericardium]], [[great vessels]], [[lung]])
** '''A:''' Without [[Invasive (medical)|invasion]] of [[great vessels]]
** '''B:''' With [[Invasive (medical)|invasion]] of [[great vessels]]
|-
| style="background: #F0F0F0;" align="center" | '''IV'''
| style="background: #F0F0F0;" |
* '''A:''' [[Pleural]] or [[pericardial]] dissemination
* '''B:''' [[Lymphatic system|Lymphogenous]] or [[Blood|hematogenous]] [[metastasis]]
|-
|}
 
====TNM Classification of Thymic Epithelial Tumors====
 
{| style="border: 0px; font-size: 90%; margin: 3px;" align="center"
|+ <SMALL>'''''TNM Classification of Thymic Epithelial Tumors by Yamakawa and Masaoka (1991)'''''<ref name="pmid3621939">{{cite journal| author=Sinha Hikim AP, Hoffer AP| title=Quantitative analysis of germ cells and Leydig cells in rat made infertile with gossypol. | journal=Contraception | year= 1987 | volume= 35 | issue= 4 | pages= 395-408 | pmid=3621939 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3621939  }} </ref></SMALL>
! colspan="2" style="background: #4479BA; color:#FFF;" | '''T/N/M Stage'''
! style="background: #4479BA; color:#FFF;" | '''Description'''
|-
| rowspan="4" style="background: #F0F0F0; width:75px;" align="center" | '''T'''  || style="background: #F0F0F0; width: 50px;" align="center" |'''T1'''
| style="background: #F0F0F0;" |
* [[Macroscopic|Macroscopically]] completely encapsulated and [[Microscopic|microscopically]] no [[Capsule (anatomy)|capsular]] [[Invasive (medical)|invasion]]
|-
| style="background: #F0F0F0;" align="center" | '''T2'''
| style="background: #F0F0F0;" |
* [[Macroscopic]] adhesion or [[Invasive (medical)|invasion]] into surrounding [[Fat tissue|fatty tissue]] or [[mediastinal pleura]], <BR> '''or''' [[microscopic]] [[Invasive (medical)|invasion]] into the [[Capsule (anatomy)|capsule]]
|-
| style="background: #F0F0F0;" align="center" | '''T3'''
| style="background: #F0F0F0;" |
* [[Invasive (medical)|Invasion]] into neighboring [[Organ (anatomy)|organs]], such as [[pericardium]], [[great vessels]], and [[lung]]
|-
| style="background: #F0F0F0;" align="center" | '''T4'''
| style="background: #F0F0F0;" |
* [[Pleural]] or [[pericardial]] dissemination
|-
| rowspan="4" style="background: #F0F0F0;" align="center" | '''N'''  || style="background: #F0F0F0;" align="center" |'''N0'''
| style="background: #F0F0F0;" |
* No [[lymph node]] [[metastasis]]
|-
| style="background: #F0F0F0;" align="center" | '''N1'''
| style="background: #F0F0F0;" |
* [[Metastasis]] to the [[Anatomical terms of location|anterior]] [[mediastinal lymph nodes]]
|-
| style="background: #F0F0F0;" align="center" | '''N2'''
| style="background: #F0F0F0;" |
* [[Metastasis]] to the [[intrathoracic]] [[Lymph node|lymph nodes]] except [[Anatomical terms of location|anterior]] [[mediastinal lymph nodes]]
|-
| style="background: #F0F0F0;" align="center" | '''N3'''
| style="background: #F0F0F0;" |
* [[Metastasis]] to [[Thoracic|extrathoracic]] [[Lymph node|lymph nodes]]
|-
| rowspan="4" style="background: #F0F0F0;" align="center" | '''M'''  || style="background: #F0F0F0;" align="center" |'''M0'''
| style="background: #F0F0F0;" |
* No [[Blood|hematogenous]] [[metastasis]]
|-
| style="background: #F0F0F0;" align="center" | '''M1'''
| style="background: #F0F0F0;" |
* [[Blood|Hematogenous]] [[metastasis]]
|-
|}
 
{| style="border: 0px; font-size: 90%; margin: 3px;" align="center"
|+ <SMALL>'''''Combined Masaoka Staging/TNM Classification (1994)'''''<ref name="pmid7921194">{{cite journal| author=Tsuchiya R, Koga K, Matsuno Y, Mukai K, Shimosato Y| title=Thymic carcinoma: proposal for pathological TNM and staging. | journal=Pathol Int | year= 1994 | volume= 44 | issue= 7 | pages= 505-12 | pmid=7921194 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=7921194  }} </ref></SMALL>
! style="background: #4479BA; color:#FFF;" | '''Masaoka Stage'''
! style="background: #4479BA; color:#FFF;" | '''T'''
! style="background: #4479BA; color:#FFF;" | '''N'''
! style="background: #4479BA; color:#FFF;" | '''M'''
|-
| style="background: #F0F0F0;" align="center" | '''Stage I'''
| style="background: #F0F0F0;" align="center" | T1
| style="background: #F0F0F0;" align="center" | N0
| style="background: #F0F0F0;" align="center" | M0
|-
| style="background: #F0F0F0;" align="center" | '''Stage II'''
| style="background: #F0F0F0;" align="center" | T2
| style="background: #F0F0F0;" align="center" | N0
| style="background: #F0F0F0;" align="center" | M0
|-
| style="background: #F0F0F0;" align="center" | '''Stage III'''
| style="background: #F0F0F0;" align="center" | T3
| style="background: #F0F0F0;" align="center" | N0
| style="background: #F0F0F0;" align="center" | M0
|-
| style="background: #F0F0F0;" align="center" | '''Stage IVa'''
| style="background: #F0F0F0;" align="center" | T4
| style="background: #F0F0F0;" align="center" | N0
| style="background: #F0F0F0;" align="center" | M0
|-
| rowspan="2" style="background: #F0F0F0;" align="center" | '''Stage IVb'''
| style="background: #F0F0F0;" align="center" | Any T
| style="background: #F0F0F0;" align="center" | N1, N2, or N3
| style="background: #F0F0F0;" align="center" | M0
|-
| style="background: #F0F0F0;" align="center" | Any T
| style="background: #F0F0F0;" align="center" | Any N
| style="background: #F0F0F0;" align="center" | M1
|-
|}
 
====Previously Reported Staging System====
 
{| style="border: 0px; font-size: 90%; margin: 3px;" align="center"
|+ <SMALL>'''''Masaoka Staging (1981)'''''<ref name="Masaoka-1981">{{Cite journal  | last1 = Masaoka | first1 = A. | last2 = Monden | first2 = Y. | last3 = Nakahara | first3 = K. | last4 = Tanioka | first4 = T. | title = Follow-up study of thymomas with special reference to their clinical stages. | journal = Cancer | volume = 48 | issue = 11 | pages = 2485-92 | month = Dec | year = 1981 | doi = | PMID = 7296496 }}</ref></SMALL>
! style="background: #4479BA; color:#FFF;" | '''Stage'''
! style="background: #4479BA; color:#FFF;" | '''Description'''
|-
| style="background: #F0F0F0;" align="center" | '''I'''
| style="background: #F0F0F0;" |
* Macroscopically completely encapsulated and microscopically no capsular invasion
|-
| style="background: #F0F0F0;" align="center" | '''II'''
| style="background: #F0F0F0;" |
* '''1.''' [[Macroscopic]] [[Invasive (medical)|invasion]] into the surrounding [[Fat tissue|fatty tissue]] or [[mediastinal pleura]]
* '''2.''' [[Microscopic]] [[Invasive (medical)|invasion]] into the [[Capsule (anatomy)|capsule]]
|-
| style="background: #F0F0F0;" align="center" | '''III'''
| style="background: #F0F0F0;" |
* [[Macroscopic]] [[Invasive (medical)|invasion]] into the neighboring [[Organ (anatomy)|organs]] ([[pericardium]], [[great vessels]], or [[lung]])
|-
| style="background: #F0F0F0;" align="center" | '''IVa'''
| style="background: #F0F0F0;" |
* [[Pleural]] or [[pericardial]] dissemination
|-
| style="background: #F0F0F0;" align="center" | '''IVb'''
| style="background: #F0F0F0;" |
* [[Lymphatic system|Lymphogenous]] or [[Blood|hematogenous]] [[metastasis]]
|-
|}
 
{| style="border: 0px; font-size: 90%; margin: 3px;" align="center"
|+ <SMALL>'''''Clinical Staging by Bergh (1978) and Wilkins (1979)'''''<ref name="Bergh-1978">{{Cite journal  | last1 = Bergh | first1 = NP. | last2 = Gatzinsky | first2 = P. | last3 = Larsson | first3 = S. | last4 = Lundin | first4 = P. | last5 = Ridell | first5 = B. | title = Tumors of the thymus and thymic region: I. Clinicopathological studies on thymomas. | journal = Ann Thorac Surg | volume = 25 | issue = 2 | pages = 91-8 | month = Feb | year = 1978 | doi =  | PMID = 626543 }}</ref><ref name="Wilkins-1979">{{Cite journal  | last1 = Wilkins | first1 = EW. | last2 = Castleman | first2 = B. | title = Thymoma: a continuing survey at the Massachusetts General Hospital. | journal = Ann Thorac Surg | volume = 28 | issue = 3 | pages = 252-6 | month = Sep | year = 1979 | doi =  | PMID = 485626 }}</ref></SMALL>
! style="background: #4479BA; color:#FFF;" | '''Author'''
! style="background: #4479BA; color:#FFF;" | '''Stage'''
! style="background: #4479BA; color:#FFF;" | '''Description'''
|-
! rowspan="3" style="background: #F0F0F0;" align="center" | Bergh et al.
| style="background: #F0F0F0;" align="center" |'''I''' ||
* Intact [[Capsule (anatomy)|capsule]] or [[growth]] within the [[capsule]]
|-
| style="background: #F0F0F0;" align="center" | '''II''' ||
* [[Capsule (anatomy)|Pericapsular]] [[growth]] into the [[mediastinal]] [[fat tissue]]
|-
| style="background: #F0F0F0;" align="center" | '''III''' ||
* [[Invasive (medical)|Invasive]] [[growth]] into the surrounding [[Organ (anatomy)|organs]] and/or [[intrathoracic]] [[Metastasis|metastases]]
|-
! rowspan="3" style="background: #F0F0F0;" align="center" | Wilkins et al.
| style="background: #F0F0F0;" align="center" |'''I''' ||
* Intact [[capsule]] or [[growth]] within the [[capsule]]
|-
| style="background: #F0F0F0;" align="center" | '''II''' ||
* [[Capsule|Pericapsular]] [[growth]] into the [[Mediastinum|mediastinal]] [[fat tissue]] or adjacent [[pleura]] or [[pericardium]]
|-
| style="background: #F0F0F0;" align="center" | '''III''' ||
* [[Invasive]] [[growth]] into the surrounding [[Organ (anatomy)|organs]] and/or [[intrathoracic]] [[Metastasis|metastases]]
|-
|}


==References==
==References==
<references />
{{reflist|2}}
 
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Latest revision as of 17:00, 21 August 2019

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Shyam Patel [2] Associate Editor(s)-in-Chief: Khuram Nouman, M.D. [2]

Overview

Thymoma can be largely diagnosed by using radiological techniques.

Diagnostic Study of Choice

Study of Choice

Staging

  • The thymic epithelial tumor staging system was initially proposed by Bergh and his colleagues in 1978, modified by Wilkins and Castleman in 1979, and further developed by Masaoka et al. in 1981.[2][3][4][5]
  • Modified Masaoka staging grouped with TNM classification is the most widely adopted system for thymic epithelial tumors currently in use.

Modified Masaoka Clinical Staging of Thymoma

Modified Masaoka Clinical Staging of Thymoma (1994)[6]
Stage Description
I
II
III
IV

TNM Classification of Thymic Epithelial Tumors

TNM Classification of Thymic Epithelial Tumors by Yamakawa and Masaoka (1991)[7]
T/N/M Stage Description
T T1
T2
T3
T4
N N0
N1
N2
N3
M M0
M1
Combined Masaoka Staging/TNM Classification (1994)[8]
Masaoka Stage T N M
Stage I T1 N0 M0
Stage II T2 N0 M0
Stage III T3 N0 M0
Stage IVa T4 N0 M0
Stage IVb Any T N1, N2, or N3 M0
Any T Any N M1

Previously Reported Staging System

Masaoka Staging (1981)[4]
Stage Description
I
  • Macroscopically completely encapsulated and microscopically no capsular invasion
II
III
IVa
IVb
Clinical Staging by Bergh (1978) and Wilkins (1979)[3][2]
Author Stage Description
Bergh et al. I
II
III
Wilkins et al. I
II
III

References

  1. Scagliori E, Evangelista L, Panunzio A, Calabrese F, Nannini N, Polverosi R; et al. (2015). "Conflicting or complementary role of computed tomography (CT) and positron emission tomography (PET)/CT in the assessment of thymic cancer and thymoma: our experience and literature review". Thorac Cancer. 6 (4): 433–42. doi:10.1111/1759-7714.12197. PMC 4511321. PMID 26273398.
  2. 2.0 2.1 Wilkins, EW.; Castleman, B. (1979). "Thymoma: a continuing survey at the Massachusetts General Hospital". Ann Thorac Surg. 28 (3): 252–6. PMID 485626. Unknown parameter |month= ignored (help)
  3. 3.0 3.1 Bergh, NP.; Gatzinsky, P.; Larsson, S.; Lundin, P.; Ridell, B. (1978). "Tumors of the thymus and thymic region: I. Clinicopathological studies on thymomas". Ann Thorac Surg. 25 (2): 91–8. PMID 626543. Unknown parameter |month= ignored (help)
  4. 4.0 4.1 Masaoka, A.; Monden, Y.; Nakahara, K.; Tanioka, T. (1981). "Follow-up study of thymomas with special reference to their clinical stages". Cancer. 48 (11): 2485–92. PMID 7296496. Unknown parameter |month= ignored (help)
  5. Kondo, K. (2005). "Invited commentary". Ann Thorac Surg. 80 (6): 2000–1. doi:10.1016/j.athoracsur.2005.08.053. PMID 16305832. Unknown parameter |month= ignored (help)
  6. Masaoka, A.; Yamakawa, Y.; Niwa, H.; Fukai, I.; Saito, Y.; Tokudome, S.; Nakahara, K.; Fujii, Y. (1994). "Thymectomy and malignancy". Eur J Cardiothorac Surg. 8 (5): 251–3. PMID 8043287.
  7. Sinha Hikim AP, Hoffer AP (1987). "Quantitative analysis of germ cells and Leydig cells in rat made infertile with gossypol". Contraception. 35 (4): 395–408. PMID 3621939.
  8. Tsuchiya R, Koga K, Matsuno Y, Mukai K, Shimosato Y (1994). "Thymic carcinoma: proposal for pathological TNM and staging". Pathol Int. 44 (7): 505–12. PMID 7921194.