Approach to Mediastinal Mass

1. Approach to Mediastinal Mass
Presenter:
Dr. Dharmendra Joshi (DJ)
Phase B Resident
Department of Thoracic Surgery
Dhaka Medical College & Hospital
1

2. A Quick Glance at our Department
(01/12/2017-30/11/2018)
Bullectomy
2%
Decortication
15%
Diaphragmatic
Operations
4%
Enucleation of
Hydatid Cyst
3%
Esophageal
Operations
29%
Excision of
Chest wall
tumor
5%
Excision of
Mediastinal
Mass
7%
Lobectomy
15%
Miscellaneous
15%
Pneumonectomy
5%
ROUTINE OPERATION DONE UNDER G/A
• Total no of operations
done under G/A: 131
• Excision of Mediastinal
Mass: 7%
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3. Contents
1. Mediastinal Anatomy
2. Mediastinoscopy
3. Anterior Mediastinal Masses
4. Middle Mediastinal Masses
5. Posterior Mediastinal Masses
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4. Mediastinal Anatomy
Four-Compartment Model Three-Compartment Model
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5. 5

6. 6

7. Contents of Anterior Compartment
a. Thymus
b. Internal Mammary Vessels
c. Areolar and Adipose Tissues
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8. Contents of Middle Compartment
• Majority of mediastinal structures:
a. Heart and Great vessels
b. Pericardium
c. Trachea
d. Proximal mainstem bronchi
e. Vagus and Phrenic nerve
f. Esophagus
g. Thoracic duct
h. Descending aorta
i. Azygos venous system 8

9. Contents of Posterior Compartment
a. Sympathetic chain
b. Proximal portions of the
intercostal neurovascular
bundles
c. Thoracic spinal ganglia
d. Distal azygos vein
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10. Mediastinal
Lymph Node
Anatomy
Mountain-Dresler Chart
adopted by American Joint
Committee on Cancer and the
Union for International
Cancer Control showing
Regional lymph node stations
for lung cancer staging
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11. Approach to mediastinal mass in general:
1. Is the mass actually in the mediastinum or is it in the lung?
2. If in the mediastinum, then in which compartment?
3. What is the differential diagnosis for the mass?
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12. Which Compartment???
1. Cervicothoracic sign
2. Thoracoabdominal sign
3. Hilum overlay and convergence signs
4. Effect on adjacent structures
• Trachea
• Ribs
• Heart
12

13. 13

14. Approach to mediastinal mass in general:
1. Evaluation with history and physical examination.
2. History is very important. Chills and night sweats more consistent
with lymphoma than thymoma or germ cell tumor.
3. Physical examination, including a good systemic examination.
4. Laboratory examination: Alpha-fetoprotein and Beta HCG (Anterior
Mediastinal tumors) and Catecholamine and Urinary VMA
(Posterior mediastinal Tumors)
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15. Approach for tissue assessment
• Percutaneous needle aspiration;
• Mediastinoscopy;
• Anterior mediastinotomy (Chamberlain procedure)
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16. Mediastinal Lymph Node Assessment
INDICATIONS:
1. Non-small cell lung cancer (NSCLC)
2. Mediastinal lymphadenopathy of unknown etiology
3. Mediastinal masses
4. Primary tracheal tumors
5. Esophageal tumors
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17. Complications of Mediastinoscopy
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1. Major vessel haemorrhage
2. Esophageal perforation
3. Stroke
4. Recurrent laryngeal nerve injury (L > R)
5. Pneumothorax
6. Wound infection
7. Tumor seeding of the neck incision

18. Anterior Mediastinal Masses
1. Thymic Tumors
2. Germ Cell Tumors
3. Lymphoma
4. Substernal Goiter
5. Hyperfunctioning
Mediastinal
Parathyroid Adenoma
18

19. Thymic Tumors
Approx. 50% of anterior mediastinal masses
1. Thymoma
2. Thymic Carcinoma
3. Neuroendocrine Tumors of Thymus
4. Others: Thymic Hyperplasia, Thymo-lipoma, Thymic Cysts etc.
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20. Thymoma:
• Most Common Anterior Mediastinal Mass.
• 95% located in anterior mediastinum
• Types:
- Predominantly lymphocyte
- Predominantly epithelial
- Mixed
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21. Classification
Schemes for
Thymoma
Masaoka and colleagues in 1981
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22. Presentation of Thymoma
• Age > 40 years
• M = F
• 50% asymptomatic
• C/F:
 Local symptoms (pain, dyspnea, cough, hoarseness) from locally
invasive tumors.
 Systemic symptoms from associated systemic diseases
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23. Systemic Diseases most commonly associated
with Thymoma
Myasthenia Gravis
Cytopenia (most commonly red
cell hypoplasia)
Non-thymic malignancies
Hypogammaglobulinemia
SLE
Polymyositis
RA
Thyroiditis
Sjogren Syndrome
Ulcerative Colitis
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24. Thymoma and Myasthenia Gravis (MG)
a. 5% to 15% of patients with MG have Thymomas
b. 30% to 50% of thymomas are associated with clinical MG
c. MG may develop later, even after thymoma resection
d. Require medical optimization before surgery
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25. Investigations:
1. CXR
2. CT Scan of chest (contrast
and non contrast)
3. MRI
4. PET
5. Serum Alpha Feto-Protein,
Beta hCG, LDH
6. Biopsy
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26. Noninvasive thymoma: well
circumscribed, solid anterior
mediastinal mass
Thymoma. Enormous soft-tissue mass in the anterior
mediastinum with posterior displacement of other
mediastinal structures. No difference in density can
be seen between the mass and the heart behind it. 26

27. Treatment of Thymoma
 Complete Surgical
resection along with
complete thymectomy
 Neoadjuvant
chemotherapy for
aggressive thymomas
 Neoadjuvant and
adjuvant radiotherapy
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28. Outcome of patient with Thymoma
It is stage specific.
Completely resected Masaoka Stage I thymoma: best prognosis.
 As the stage increases, recurrence rates increase and survival
decrease.
Historically, the presence of thymoma was believed to affect the
outcome adversely after thymectomy for MG but NOT true now.
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29. Thymic Carcinoma
1. Rare invasive epithelial
malignancies.
2. 5 years survival: 33%
3. Treatment:
Multimodality approach
 Induction Therapy
 Resection (if possible)
 Postoperative radiation (if
not done preoperatively)
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30. Neuroendocrine Tumors of the Thymus
Thymic carcinoid
1. M > F
2. 1/3rd present with Cushing
syndrome
3. Treatment: Complete excision
4. Outcome: poor
Small cell carcinoma of the thymus
1. Very uncommon
2. Extremely aggressive
3. Treatment:
Chemotherapy and/or
Radiotherapy
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31. Germ Cell Tumors (GCTs)
1. Benign Mediastinal Teratoma
2. Malignant Mediastinal Germ Cell Tumors
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32. TERATOMA
Mature Teratoma
• Well defined, smooth, cystic
• Teeth and bone rare
• Fluid in 90%; fat in 75%;
calcification in 50%
Immature Teratoma
• Malignant teratoma
• Nodular or poorly defined
• Fat in 40%
• Compression or invasion of
mediastinal structures
• Enhancing capsule
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33. Benign Mediastinal Teratoma
- 60% of mediastinal GCTs.
C/F:
a. Asymptomatic in adult or cough and discomfort/pain when large.
b. Children: symptoms of airway compression.
Investigation:
• CXR
• CT scan of chest
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34. Benign Mediastinal Teratoma (Investigations)
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35. Benign Mediastinal Teratoma (Investigations)
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36. Benign Mediastinal Teratoma
Treatment:
a. Complete excision
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37. Malignant Mediastinal Germ Cell Tumors
• Diffuse Anterior Mediastinal Masses
• Frequently invade surrounding structures
• M > F
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38. Malignant Mediastinal Germ Cell Tumors
• Types:
1. Seminomatous (40%)
2. Non seminomatous (60%)
Embryonal Cell Carcinoma
Choriocarcinoma
Yolk Sac Tumors
Teratocarcinomas
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39. Malignant Mediastinal Germ Cell Tumors
Physical examination: testicular examination in male patients
Investigations:
USG of Testicles in male
CT scan of the chest, abdomen and pelvis
Serum B-hCG, AFP and LDH
Needle biopsy
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40. Malignant germ-cell tumour. The CT shows a lobular
asymmetrical mass with low attenuation areas corresponding
to necrotic tumour intersected by neoplastic septation.
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41. Malignant Mediastinal Germ Cell Tumors
• Treatment:
1. Pure mediastinal seminomas: extremely radiosensitive.
But today primary treatment is cisplatin based chemotherapy.
2. Non seminomas: Three drug chemotherapy
- etoposide
- ifosfamide
- cisplatin
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42. Lymphoma
Both Hodgkin disease and
non-Hodgkin lymphomas
may appear as anterior
mediastinal masses
Diagnosis:
1. Clinical history
2. CT scan
3. Biopsy (Surgical rather
then needle biopsy)
4. Flow cytometry
42

43. Lymphoma
Both Hodgkin disease and
non-Hodgkin lymphomas
may appear as anterior
mediastinal masses
Diagnosis:
1. Clinical history
2. CT scan
3. Biopsy (Surgical rather
then needle biopsy)
4. Flow cytometry
43

44. Substernal Thyroid and Ectopic Thyroid Tissue
Substernal Thyroid
Enlarged thyroid may be
palpable in most cases
CXR may show deviation of
trachea
CT scan without contrast is
the single most useful test
Substernal goiter treatment:
Thyroid Resection by cervical
approach or partial sternal
split.
44

45. Hyperfunctioning mediastinal parathyroid adenoma
Patients exhibit primary hyperparathyroidism after unsuccessful neck exploration.
Localization studies should be performed before mediastinal exploration.
CT and MRI may reveal well defined mass.
Technetium 99m-sestamibiscintigraphy is the most useful study.
Treatment: Resection via
transcervical approach via
median sternotomy or by
thoracoscopy
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46. Biopsy for Anterior Mediastinal Mass
Indications for resection:
1. CT or MRI shows features pathognomonic of teratoma
2. Patient is older than 40 years, without clinical signs or symptoms of
lymphoma and with normal AFP and BHCG
3. The mass is associated with MG
*** In most other instances, biopsy is indicated.
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47. Approach to Middle Mediastinal Masses
• Signs/Symptoms:
1. Often asymptomatic
2. Common symptoms:
Cough
Dyspnea
Chest pain
47

48. Approach to Middle Mediastinal Masses
• Imaging:
1. CXR
2. CT scan of chest
3. MRI
4. PET
5. Endobronchial ultrasonography (EBUS)
6. Transesophageal ultrasonography (EUS)
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49. Diseases of Middle
Mediastinum
1. Mediastinal Infections
2. Mediastinal lymphadenopathy
3. Tracheal Disorders
Primary tumors: SCC and Adenoid
Cystic Carcinoma
Bronchogenic cysts (80%)
4. Pericardial Disorders
Pericardial cysts (1:1,00,000)
Pericardial neoplasms
49

50. Diseases of Middle
Mediastinum
1. Mediastinal Infections
2. Mediastinal lymphadenopathy
3. Tracheal Disorders
Primary tumors: SCC and Adenoid
Cystic Carcinoma
Bronchogenic cysts (80%)
4. Pericardial Disorders
Pericardial cysts (1:1,00,000)
Pericardial neoplasms
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51. Approach to Middle Mediastinal Masses
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52. Approach to Middle Mediastinal Masses
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53. Pericardial Cyst Bronchogenic Cyst
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54. Pericardial Cyst Bronchogenic Cyst
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55. Approach to Middle Mediastinal Masses
• Invasive Techniques to obtain tissue for diagnosis:
1. CT-guided Percutaneous Biopsy
2. EUS and EBUS guided biopsy
Fine-needle biopsy
Core needle biopsy
3. Cervical mediastinoscopy and anterior mediastinotomy
4. VATS
5. Thoracotomy or sternotomy
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56. Approach to Posterior Mediastinal Masses
• Posterior Mediastinal Masses:
1. Neurogenic Tumors
2. Esophageal masses
3. Cysts
4. Others
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57. Approach to Posterior Mediastinal Masses
• Diagnosis:
1. Symptomatic: Adult: 50-60%. Children: 60-80%
2. Incidence of symptoms parallels to incidence of malignant lesions.
3. Detail history and physical examination
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58. Approach to Posterior Mediastinal Masses
• Investigations:
1. CT scan is the imaging modality of choice.
2. MRI (dumbbell tumors, cyst etc.)
3. Serum epinephrine and norepinephrine, Urinary VMA levels
4. Mediastinal sonography NOT useful.
5. Biopsy (CT guided FNAC, thoracoscopic, limited posterolateral
thoracotomy)
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59. Neurogenic Tumors
• Common in young adults and children
• 15% of all mediastinal masses in adults
• Types: Benign and Malignant
> Benign: Neurilemoma (Schwannoma) or Neurofibroma
> Malignant: Neurogenic sarcomas or malignant schwannomas rare.
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60. Origin of Neurogenic Tumors in Posterior Mediastinum
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61. Neurilemomas (Schwannomas)
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62. Neurilemomas (Schwannomas)
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63. Neurilemomas (Schwannomas)
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64. Ganglioneuroma
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65. Ganglioneuroma
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66. Ganglioneuroma
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67. Ganglioneuroma
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68. Ganglioneuroma
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69. Ganglioneuroma
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70. Ganglioneuroma
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71. Treatment of Neurogenic Tumors
• Surgical intervention is the standard of care
Posterolateral Thoracotomy
VATS
• Biopsy should be performed only if the results will alter therapy.
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72. Esophageal Masses
• Neoplasm
• Esophageal cysts
• Diverticula
• Hiatal hernias
• Megaesophagus
• Esophageal varices
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73. Cysts of Posterior Mediastinum
• Bronchogenic Cysts
• Gastroenteric Cysts
• Neuroenteric Cysts
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74. Bronchogenic Cysts
 60% of all mediastinal cysts.
 It may be located in the lung
parenchyma or mediastinum
 Observation is advocated for
preoperatively diagnosed
asymptomatic bronchogenic cysts.
 Symptoms including pain, cough
or hemoptysis suggests resection.
 Resection is done if suspicious of
malignant transformation,
positive cytology or evidence of
enlargement or recurrence.
74

75. Gastroenteric Cysts
 Esophageal duplication cysts
 Periesophageal lesions
 May involve both middle or posterior
mediastinum
 Asymptomatic or respiratory
compromise and chest pain uncommon
 Presence of gastric mucosa may
perforate esophagus
 Esophageal USG, CT chest or contrast
study helps diagnosis
 Resection is therapy of choice
 Observation may be best approach for
asymptomatic clearly cystic lesion
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76. Gastroenteric Cysts
 Esophageal duplication cysts
 Periesophageal lesions
 May involve both middle or posterior
mediastinum
 Asymptomatic or respiratory
compromise and chest pain uncommon
 Presence of gastric mucosa may
perforate esophagus
 Esophageal USG, CT chest or contrast
study helps diagnosis
 Resection is therapy of choice
 Observation may be best approach for
asymptomatic clearly cystic lesion
76

77. Gastroenteric Cysts
 Esophageal duplication cysts
 Periesophageal lesions
 May involve both middle or posterior
mediastinum
 Asymptomatic or respiratory
compromise and chest pain uncommon
 Presence of gastric mucosa may
perforate esophagus
 Esophageal USG, CT chest or contrast
study helps diagnosis
 Resection is therapy of choice
 Observation may be best approach for
asymptomatic clearly cystic lesion
77

78. Gastroenteric Cysts
 Esophageal duplication cysts
 Periesophageal lesions
 May involve both middle or posterior
mediastinum
 Asymptomatic or respiratory
compromise and chest pain uncommon
 Presence of gastric mucosa may
perforate esophagus
 Esophageal USG, CT chest or contrast
study helps diagnosis
 Resection is therapy of choice
 Observation may be best approach for
asymptomatic clearly cystic lesion
78

79. Neuroenteric Cysts
 Occurs in Infants
younger than 1 year
 Uncommon in adult
 Usually associated
with congenital
defects of spine
 CT scan is choice of
imaging modality
79

80. Other Posterior Mediastinal Masses
• Primary or metastatic Spine tumors,
• Lymphomas,
• Infection (TB) may result paravertebral mass,
• Descending thoracic aneurysm,
• Castleman disease (giant lymph node hyperplasia)
• Angiomyolipoma
• Extra lobar pulmonary sequestration
• Neuroendocrine carcinoma etc.
80

81. Video Demonstration
(VATS excision of Mediastinal Mass)
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82. 82