Transcript Slide 1

Mediastinal
Syndromes
1
• Division
Mediastinum
- Superior,
- Inferior
- Anterior,
- Middle,
- Posterior compartments.
• The mediastinum contains all of the vital
structures of the chest except the pulmonary
parenchyma.
Mediastinal Regions
Mediastinum
• The superior mediastinum lies between the
manubrium and thoracic vertebrae one to four.
• The anterior mediastinum is bounded by the
sternum anteriorly and pericardium posteriorly.
• The middle mediastinum consists of the heart
and vascular structures; anything in the middle
of the chest that is radio dense on lateral
radiograph is within the middle mediastinum.
• The posterior mediastinum lies between the
heart and the vertebral bodies.
Subdivision of mediastinum
• anterior mediastinum
• middle mediastinum
• posterior
mediastinum
Mediastinal Lesions
• Any lesion that occurs in the mediastinum –
can be focal or diffuse.
• CT scan or MRI with contrast is usually
indicated for further evaluation.
Mediastinal Lesions
Focal vs Diffuse
Anthrax
Thymoma
1. Superior Mediastinum
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Aortic Arch & its branches
Brachiocephalic and subclavian vessels
Superior vena cava upper half & tributaries
Trachea
Thyroid
Oesophagus
Thoracic duct
Phrenic ,Vagus ,Cardiac, Lt.Recurrent L nerves
2. Anterior Mediastinum
Anterior mediastinum
Anterior Mediastinal Masses
•Thymus
•Thyroid
•Ectopic Thyroid Tissue
•Parathyroid Gland
•Internal mammary vessels
•Lymph nodes
•Aortic Arch
•SVC Superior Vena Cava
•Thymic lesions (and
parathyroid masses)
•Teratomas (and other germ cell
tumors)
•‘Terrible' lymphoma
•Tortuous vessels
•Dissecting aorta, right arch
•Trauma
•Aortic aneurysm,
•Pericardial cyst,
•Epicardial fat pad
•Lymphadenopathy.
Anterior mediastinal mass
Anterior Mediastinal Mass
T-cell
Lymphoma
Mediastinal Lesions
• Anterior lesions –
thymoma, thyroid
lesions, teratoma, tcell lymphomas, and
lymphadenopathy.
• Usually seen in
retrosternal space.
anterior
lesion.
Lymphoma
Mediastinal Lesions
• Lateral view shows a
solid tissue density in
the region anterior and
superior to the heart.
• Lymphoma is the most
common anterior
mediastinal mass.
Lymphoma
3. Middle Mediastinum
Middle mediastinum
 Heart and pericardium
 Ascending aorta
 Superior vena cava
 Azygous vein
 Phrenic and vagus nerves
 Trachea
 Trachea Bifurcation and
main bronchi
 Pulmonary arteries and veins
 Hilar Lymph Node
Middle Mediastinal Mass
 lymphadenopathy due to
metastases or primary tumor.
 Other causes include
 hiatial hernia,
 aortic aneurysm,
 Thyroid mass,
 duplication cyst, and
 bronchogenic cyst.
Mediastinal Lesions
• Middle lesions –
thoracic aortic
aneurysms,
hematomas, neoplasms,
lymphadenopathy,
esophageal lesions, and
diaphragmatic hernias.
• Enlarged lymph nodes
are the most frequent
cause of a middle
mediastinal mass.
lymphadenopathy
Mediastinal Lymphadenopathy
• InfectionPneumonia, TB,
Anthrax
• Inflammation Sarcoidosis
• MalignancyLymphoma,
Metastatic
4. Posterior Mediastinum
Posterior
Posterior mediastinal
mass
•Esophagus
•Thoracic duct
•Thoracic descending
•Aorta Descending
•Azygos
•Hemiazygos vein
•Vagus nerves
•Sympathetic Chain
•Paravertebral Lymphnode
•Neurogenic lesions,
•Neoplasm ,
•Lymphadenopathy ,
•Aortic aneurysm,
•Adjacent pleural or lung mass,
•Neurenteric cyst or lateral
meningocele, and
•Extramedullary hematopoiesis
Mediastinal Lesions
• Posterior lesions –
Neurogenic lesions,
hiatal hernias,
descending aortic
aneurysm, neoplasms,
and hematomas.
• 90% of posterior
lesions are neurogenic
lesions.
Aneurysm of Descending Aorta
Posterior mediastinal masses will give double
density over left side of heart.
Origins of Mediastinal Mass
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Developmental
Neoplastic
Infectious
Traumatic
Cardiovascular disorders
Mediastinologists
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Thoracic Surgeon
Pulmonologist
ENT
Cardiologist
Endoscopist
Radiologist
Differentials
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Diaphragmatic lesions; eventration ,hernia
Esophageal tumours ,achalasia
Mediastinal metastasis
Mediastinal lymph nodes: lymphomas,
granulomas
Thyroid retrosternal extension
Aneurysm of aorta
Ventricular aneurysm
Tracheal , heart tumours
Incidence
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1 in 100000
Thrice more common than bronchial adenoma
1/3000 admission at large medical centre
Neural commonest 20-27%
Thymic second 19-26%
Cyst third 18-21%
Teratomas \ lymphoma fourth 12%
Neural , Thymic, developmental ,Lymphoma
:88% of all mediastinal tumours
Children
Adult
•Neural tumours 40%
•Lymphoma 20%
•Teratomas & Cysts 10-15%
•Thymic rare
•Posterior Mediastinum
•Most often benign
•2/3 of tumors symptomatic
•Neural tumours 20-27%
•Thymic 19-26%
•Cyst third 18-21%
•Teratoma \ lympho 11-12%
•Anterior Mediastinum
•Often Malignant
•1/3 of tumors are
symptomatic
•Ages 30 – 50
Malignant Tumors Invasion
Structure
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Tracheobronchial tree and lungs
Esophagus
Superior Vena Cava
Pleura and Chest Wall
Intrathoracic nerves
Primary Mediastinal Tumors
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Neural
– Nerve sheath
– Autonomic nervous
system
– Malignant peripheral
nerve sheath
– Granular cell tumour
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Thymic
Thyroid
• Germ cell tumours
– Benign
– Malignant
• Seminomatous
• Non seminomatous
• Lymphomas
• Developmental cysts
• Pleuropericardial cysts
Symptoms
• Cough often recurrent
• Shortness of Breath may
be with wheeze
• Chest pain
• Fever
• Chills
• Weight loss
• Night Sweats
• Hemoptysis
• Airway compression with
– Stridor
– Hoarseness
• Esophageal compression
– dysphagia
• SVC compression ….
– Neck vein engorgement,
– facial swelling
• Rt.ventricular outflow obstn
– Pericarditis
– Cardiac temponade
– Heart failure
Mediastinal Neural tumours
Nerve sheath t0
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Benign (neurolemmoma)
– Schwannoma
– Neurofibroma
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Malignant peripheral
nerve sheath t0
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Neurosarcoma
Neurofibrosarcoma
Neurogenic sarcoma
Malignant schwannoma
Malignant neurinoma
• Granular cell tumour
Granular cell myoblastoma
– Autonomic nervous
system (neurocyte)
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Ganglioneuroma
Ganglioneuroblastoma
Neuroblastoma
Paraganglioma
– Aorticopulmonary
– Aorticosympathetic
Large Neuroma
Ganglioneuroma
Ganglioneuroblast Neuroblastoma
oma
•Most common
•< 20 yrs age
•Posterior
mediastinum
•Rare tumour in adults
•50% in first 3 yr of age
•Majority occur in
adrenal medulla
•Sex : equal
•Equal among both sex
•Often pear shaped or
lobulated
•Majority are
encapsulated
•Must be regarded as
malignant
•Encapsulated
•Slow growing
•Benign, May
be malignant
•Adults rarely
•Within 2 yrs ,
•Posterior mediastinum
•Adrenal medulla, 20%
in thorax
•Retroperitoneal
•Equal in both sexes
•Radio-logically less
well defined
•Highly malignant
•Locally invasive
•Spontaneous
regression may occur
Intrathoracic Meningocele
Thymus of a Neonate
Thymus
– Thymic hyperplasia
– Thymoma
– Thymic cyst
– Thymic carcinoma
– Thymic carcinoid tumours
– Thymolipoma
– Germ cell tumours
– Ectopic parathyroid adenomas
– Lymphoma
– Secondary neoplastic
Thymic hyperplasia
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Nearly always infantile or childhood
Usually asymptomatic
Pronounced in HIV, SLE,Thyrotoxicosis
Indistinct from other thymic t0 on Radio or
CT
• Steroids may reduce
• Subtotal surgery
Thymoma
• Epithelial neoplasms
• most common primary neoplasms of the anterior
superior mediastinum
• Any age , rare <20, nearly all middle-aged adults.
• Male predominance
• ½ of the patients are asymptomatic
• 25-30% of patients have symptoms related to
compression of adjacent mediastinal structures
including cough, chest pain, and shortness of
breath
Thymoma
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may have myasthenia gravis (30-40%),
pure red cell aplasia,
hypogammoglobulinemia,
endocrine disorders
can be completely encapsulated (benign) or locally
invasive without a fibrous capsule
• classified by predominant cell types:
– epithelial,
– lymphoid, or
– Biphasic , mixed or lymphoepithelial type
• one- third of thymomas are invasive and may grow into
the surrounding mediastinal structures,
Thymoma
• This is determined at surgery and is not a
histologic diagnosis,
• local invasion of the pleura occurs frequently,
• distant metastases are infrequent
• Surgical removal enmass with capsule intact
– Median sterotomy
– Thoracotomy
– Transcervical approach
• Radiotherapy usually reserved for incomplete
excission
• Chemo-sensitive (May be) : cis, doxo, vin, c-phos
Encapsulated thymoma
Invasive Thymoma
Germ cell tumours
• As a result of the proliferation of the primary
extragonadal germ cell
• Mostly found near the midline
– Adults :anterior mediastinum
– Child : sacrococcygeal area
Germ cell tumours
• Benign
– Mature cystic teratoma
• Malignant
– Seminomatous* :
– Non Seminomatous*
Anterior mediastinal mass
Teratoma
Malignant Germ
cell tumours
• Seminomatous* : Seminoma
– Exclusively young male 20-40 yrs
– 1/3 asymptomatic ,
– Chest pain, dysponea, SVC obstruction
– Radio ; lobulated , non cacified ,anterior mediastinal
– Normal serum AFP
– USG testicle discrete hypoecoic masses,with
microcalcifictions
– Treatment ; chemotherapy* , Radio or combi
• Et +cis *4 cycle or Et +cis +bleo * 3 cycles
• Highly radiosensitive radio reserved for bulky
Mediastinal Lymphoma
• Mediastinum is involved in 50% Hodgkin’s
diseases
• Most cases are of nodular sclerosing type
• Treatable and many are curable too
• Intensive chemotherapy or radiotherapy or both
• Radio alone relapse 50-74%
• Chemo alone relapse 33-50%
• “MOPP” or “DBVD” followed by radio preferred
Anterior mediastinal nodes
Lymphoma
Anterior mediastinal nodes
Lymphoma
Mediastinal Mesenchymal
tumours
Benign
Lipoma
Hemangioma
Lymphangioma
Cystic hygroma
Malignant
Liposarcoma
Leiomyosarcoma
Rhabdomyosarcoma
Hemangiosarcoma
Angiolipoma
Developmental Mediastinal cysts
• Congenital ; 16% of all mediastinal cyst
• Foregut duplication largest group
• Pleuropericardial next to it
Pleuropericardial cysts
• Synonyms
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Pericardial cyst
Coelomic cyst
Spring water cyst
Hydrocele of
mediastinum
• 1 / 100000 per year
• 70% occur in right
cardiophrenic angle
– Usually anterior
• Male : Female 1 :1
• All ages
• 5 – 25 cms
• Soft , unilocular
• Crystal clear spring
water , transudate with
acellular & little
proteins
– Asymptomatic
– Chest pain
• Radiograph
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Sharply demarcaed
Rounded
Smooth edged
Anterior mass
Middle Mediastinal Cysts
Bronchogenic Cyst
Pericardial Cyst
Aortic aneurysm
Diagnostic of mediastinal
masses
• Chest X-Rays
• CT ( Computed
Tomography)/MRI
• Radionuclide Scanning
– Goiter
• Barium studies
– Most valuable for diagnosis
– For: hernia,diverticuli,achalasia
– Done in most of cases
• Percutaneous fine needle biops
• CT guided needle biopsy
• Mediastinoscopy / ant.
mediastinotomy
– Definite diagnosis
• Mediastinoscopy/ant.
medistinotomy with biopsy
– Definite with establishing the
disease diagnosis
• endoscopic ultra sound
guided biopsy
• Video assisted thoracoscopic
removal of mass
Mediastinoscopy
Mediastinoscopy: Overused, Invasive, Limited
Applications
• Mediastinoscopy:
Invasive, requires general anesthesia.
Subcarinal and subaortic (a-p window)
nodes inaccessible.
Thoracoscopy: Limited to
inferior mediastinum
• Thoracoscopic biopsy (video-assisted
thoracoscopy)
Limited to inferior mediastinum.
Endoscopic Ultrasound:
No incision, no anesthesia
Endoscopic ultrasound guided biopsy of
mediastinal lesions has a major impact on
patient management.
• It is a safe and sensitive minimally invasive method
for evaluating patients with a solid lesion of the
mediastinum suspected by CT scanning.
• It has a significant impact on patient management
and should be considered for diagnosing the
spread of cancer to the mediastinum in patients
with lung cancer considered for surgery, as well as
for the primary diagnosis of solid lesions located in
the mediastinum adjacent to the oesophagus.
Thorax 2002 Feb;57(2):98-103
• “Endoscopic ultrasonography also
provides information helpful for clinical
staging of lung cancer and is the
procedure of choice for performing fineneedle aspiration biopsy of posterior
mediastinal and subcarinal lymph nodes.”
AJCC manual 2007
CT scan or MRI
• CT scan or MRI with contrast is always
indicated for further evaluation.
• MRI is preferred for neurogenic lesions but
obtaining a CT scan is never wrong with a
mediastinal mass.
• CT-guided transthoracic fine needle
aspiration (FNA):
Limited by surrounding vascular structures,
size of the targeted lesion.
– Pneumothorax risk.
Prognosis
• Varies depending on type of tumors
and resection.
• Benign tumors – excellent prognosis
• Malignant tumors – depends on the
type