Transcript Mediastinum

MEDIASTINAL
DISEASES
University Hospital in Łódź
Clinic of Thoracic Surgery,
General Surgery and Oncology
Author: dr n.med. Sławomir Jabłoński
Mediastinum-
anatomical borders:
 from the top: superior aperture of the thorax,
 from the bottom: superior surface of the diaphragm,
 from the front: posterior surface of the sternum,
 from the back : front surface of the spine and ribs,
 from the side : plaques of the mediastinal pleura.
Topographically mediastinum is divided into three parts,
which include given organs:
 upper-anterior: thymus, large vessels,
 central: tracheal bifurcation, main bronchi, heart,
 posterior: oesophagus, aorta, vagus nerve, sympathetic trunks,
lymphatic vessels, azygos vein system.
MEDIASTINAL TUMORS
As for histogenesis mediastinal tumors come from different tissues.
„ In no other part of human body there are not as many
different tumors on such a small space ”.
Benszny’ak I. I wsp. Wyd. Akademiai Kiado, Budapest, 1984
Primary mediastinal tumors come from connective tissue, blood and
lymphatic vessels.
Approximately 55% of tumors are located in an upper-anterior part,
25% in posterior mediastinum and 20% in central mediastinum.
Benign tumors of mediastinum are about 60-75% of all tumors.
A part of these tumors is located in a characteristic way in this anatomical
area.
Histopathologic classification of
mediastinal tumors - Davis - 1987r.
 1. Neurogenic tumors (p.m.),
 2. Thymic tumors (a.m.),
 3. Lymphomas (c.m),
 4. Embrional tumors (a.m),
 5. Mesenchymal tumors (a.m. c.m.),
 6. Endocrine tumors (a.m.),
f.m – anterior mediastinum
c.m- central mediastinum
p.m- posterior mediastinum
Histopathologic classification of
mediastinal tumors - Davis - 1987r.
 7. Primary cancers (c.m.),
 8. Other unclassified tumors,
 9. Cysts:
a/ pericardial (c.m.),
b/ bronchial (c.m.),
c/ from alimentary tube (p.m.),
d/ others.
Davis R.D.: Ann. Thorac. Surg. 1987, 44, 229.
Mediastinal pseudotumors
 Aortic aneurysm,
 Heart tumors,
 Oesophageal tumors,
 Retrosternal goitre,
 Inborn Morgagni – Larrey diaphragmatic
hernias,
 Neoplastic metastases to mediastinal
lymphatic nodes.
Frontal mediastinum
Frontal mediastinum tumors:
 retrosternal and mediastinal goitre
 thymomas
 embrional tumors
(dermatoid cyst, teratomas)
 mesenchymal tumors
 lymfadenopathies (Hodgkin disease,
non-Hodgkin lymphomas
 aneurysms
LOCATION OF MEDIASTINAL TUMORS AND CYSTS
UPPER-ANTERIOR
MEDIASTINUM
CENTRAL
MEDIASTINUM
POSTERIOR
MEDIASTINUM
cysts
lymphomas
neurogenic tumors
teratomas
bronchial cysts
lymphomas
persistent thymus
pericardial cysts
thymal tumors
oesophageal cysts
retrosternal goitre
hydatid cyst
Hodgkin’s disease
lymphangiomas
T lymohomas
fibromas
carcinoid
chondromas
germinal tumors
sarcocarcinomas
metastases
carcinomas
thymomas
choristoma
granulomas
retrosternal goitre
Mediastinal tumors – clinical picture
 80 % of benign tumors – asymptomatic course until the
tumor is large and presses other mediastinal structures,
 80% of malign tumors – clinical symptoms reveal early in
connection to aggressive course of the disease
The lack of clinical symptoms is observed most frequently in
cysts and benign tumors of posterior mediastinum.
Anterior mediastinum tumors due to their location close to
different organs cause pressure symptoms quite early.
Mediastinal tumors – clinical picture
Most mediastinal tumors cause similar clinical
symptoms:
TOPICAL SYMPTOMS:
GENERAL SYMPTOMS:
 cough,
 stridor,
 displacement of trachea,
 superior caval vein syndrome,
 thoracic pain,
 pleural exudate,
 dysphagia
 Horner syndrome,
 hoarsness
 fever
 muscle strain
 cutaneous rash
 pruritus
 cancerous cachexia
Mediastinal tumors - diagnosis
Diagnostic procedures must provide
answers to three basic questions:
Isn’t the observed shadow a vascular
structure?
 Will a complete surgical treatment be
possible ?
 Is the surgical treatment necessary?

Mediastinal tumors - diagnosis
Mediastinum is difficult to be examined phisically and poor clinical
symptoms cause that almost 2/3 of all tumors may be difficult to
differenciate:
Methods of describing the location of tumor in the
mediastinum:
1. Chest X-ray,
2. Computer tomography with contrast,
3. NMR examination,
4. Transesophageal echography (TEE),
5. Conventional and transesophageal ultrasound
examination,
6. Angiography ( exclusion of aneurysms and inborn
malformations of vascular system),
Mediastinal tumors - diagnosis
Methods of describing histopathological type of tumor:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Transcutaneous biopsy (controlled by CT or ultrasound – difficult to reach
the tumor, no possibility of recognition of proliferation from lymphatic
system),
Open biopsy,
Parasternal mediastinotomy,
Carlens’ mediastinoscopy,
Transbronchial biopsy,
Biopsy from above scalene muscle ( Daniels)
Small thoracotomy,
Videothoracoscopy,
Sternotomy with direct histopathological examination,
Mediastinal tumors - diagnosis
Examination of neoplastic markers:
1.
2.
3.
4.
S-100 (neurogenic tumors),
CLA, L26, MT1, UCHL1 (lymphomas),
Leu M1 (granulomatosis),
Alphafetoprotein (AFP)
Choriongonadotropin (HCG)
(embrional tumors).
Mediastinal tumors - treatment
THE AIMS OF SURGICAL TREATMENT:
1. Removal of the tumor (complete operation),
2. Partial removal of the tumor (cytoreductive
procedure – lessening of pressure symptoms)
3. Histopathological diagnosis, assessment of
possible methods of combined treatment
Mediastinal surgery - history
 Sauerbruch – 1912 r excision of thymus from cervical
approach

Blalock - 26.05.1936r
- first excision of thymic tumor
from approach by sternotomy
 Manteuffel, Bross, Rzepecki, Dębicki creators of modern Polish thoracic surgery.
First operations of thymus excisions from approach by sternotomy burdened
high mortality rate - 30%, that is why cervical approach was used for many
years.
Mediastinal tumors – surgical treatment
OPERATIVE APPROACHES TO MEDIASTINUM:

Cervical approach ( benign thymomas, retrosternal goitre)

Longitudinal sternotomy and partial upper sternotomy (anterior
mediastinum tumors, part of anterior mediastinum tumors)

Thoracotomy (posterior and central mediastinum tumors)

Little invasive approach without division of sternum
( cervical-substernal-videothoracoscopic)
DIAGNOSTIC APPROACHES:




mediastinoscopy
parasternal mediastinotomy
videothoracoscopy
cervical approach
Mediastinal tumors – surgical tactics
1.
X-ray, CT, NMR, ultrasound examinations  possibility of total
removal of anterior or posterior mediastinum tumors:
Operative treatment (even without histopathological examination)
2.
X-ray, CT, NMR, ultrasound examinations  non-operative
mediastinal tumor no matter where located or central mediastinum
tumors matching enlarged lymphatic nodes:
Detailed histopathological examination giving a chance for
oncological treatment (chemotherapy, radiotherapy).
3.
Operation reducing the mass of the tumor (cytoreduction) –
in some tumors enables application of morw effective combined
treatment in less toxic doses.
Non-operative methods of treatment of
mediastinum tumors
In the past few years there has been an important progress in
treatment of many neoplasms including mediastinal
tumors with non-surgical methods (chemotherapy,
radiotherapy). Assessment of the histopathological type of
tumor enables choosing the best method of treatment
-
Hodgkin’s disease ( from 15% to 75%),
Embryonal tumors ( from 15% to 80%),
Embryonal neurinoma (about 50%).
odsetek
5-letnich
przeżyć
Operative treatment of
mediastinal tumors in Poland
 200 operations per year.
 Perioperative mortality = 0-3%.
 78% - radical operations,
[0,8%].
 10% - non-radical operations, [5,7%].
 12% - exploratory operations, [3,4%].
Neurogenic mediastinal tumors
They are the most frequent mediastinal neoplasms (about 20-30%) –
benign tumors prevail.
Main histopathological types:
Tumors originating from neurilemmas:
 schwanoma
 neurofibroma
Tumors originating from ganglion:
 neuroblastoma
 paraganglioma
Neurogenic mediastinal tumors

Located in posterior mediastinum (80-95%),

6-10% are malignant tumors requiring combined
treatment,

Benign hourglass tumors: posterior access
micro-neuro-surgical + anterior access
videothoracoscopic.
Thymomas
Thymomas – tumors originating from epithelial
tissue of thymus ( do not include tumors such
as theratomas, lymphomas and carcinoid).
Location: anterior mediastinum
We identify:
-
In some cases they co-exist
with (myasthenia gravis)
benign hypertrophy of thymus
thymic cysts
thymic carcinoma
Non-invasive thymus tumors have a distinct capsule. An important criteria of
diagnosing aggressive tumors is infiltration of the capsule. This is the basis of
IV-stage classification of topical progression of thymomas according to Masaoka).
Radical excision of tumor is possible in stage I and II and rarely is III.
MYASTHENIA GRAVIS
An autoimmunological disease.
Pathomechanism of myasthenia involves creating antibodies against
acethylocholin receptor (AchR) located on the membrane of neuromuscular
plaque, which leads to disorders in conduction of nerve impulses to the
muscles and as a result weakening of muscle strength.
The main threat for the patient is respiratory insufficiency due to respiratory
muscles disorders.
The main part in creating the antibodies against AchR plays the thymus.
Myasthenia in thymic tumors:
 thymomas are responsible for about 9%-16% of all cases of
myasthenia
 myasthenia accompanies about 30%-61% of all diagnosed
thymomas
Clinical classification of myasthenia according to OSSERMAN and GENKINS
TYPE
Form
Symptoms
TYPE I
( 15%-20%)
OPHTALMICAL
Limited to eyeball muscles and external eye muscles.
Papebral drop, squint, blurred speech.
In 40% of patients there is a generalization of the disease.
TYPE II A
( 30%)
GENERAL MILD
Concerning cranial, limb and trunk muscles.
Respiratory muscles function properly. Good response to
anticholinergic treatment. Low mortality rate.
TYPE II B
( 20%)
GENERAL
MODERATE
Intensive ophthalmic symptoms. Bulbar symptoms present
(dysarty, dysphagy, choking, aspiration pneumonia).
Distinct weakening of muscle strength of limbs
TYPE III
( 11%)
SEVERE
ACUTE
Sudden beginning. Severe dysfunction of bulbar, limb and
trunk muscles. Respiratory insufficiency, application of
respirator necessary (myasthenic crisis). Poor reaction to
medications. High mortality rate.
TYPE IV
(9%)
SEVERE
LATE
Progression from mild forms of myasthenia after over 2
years of the disease. Frequent occurrence of thymomas.
Unfavorable prognosis.
MYASTHENIA GRAVIS
DIAGNOSIS:
ASSESSMENT OF NEUROMUSCULAR
CONDUCTION:
 clinical symptoms of muscle strain
 test with intravenous injection of Tensilon
 examination of neuromuscular conduction
(electrophysiological tests)
 marking antibodies against AchR receptors
METHODS OF THYMUS ILLUSTRATION:
 classic and stratified chest X-rays
 computer tomography
 magnetic resonance
MYASTHENIA GRAVIS
PRESERVATIVE TREATMENT:
 anticholinesterase medicines (Mestinon, Polstigminum, Metylase)
 glucocorticosteroids
 immunosuppressive medicines (Cyklofosfamid, Azatiopryna,
Cyklosporyna)
 immunoglobulins
 plasmapheresis
OPERATIVE TREATMENT:
The procedure of excision of the thymus is called thymectomy.
The presence of thymoma or other thymic tumor is an indication to operative
treatment.
Patients in stage II A and II B with high AchR antibody ratio are qualified to
operation.
Excision of thymus lessens the symptoms or leads to their complete
withdrawal.
METHODS OF THYMECTOMY
The aim of thymectomy is to remove the thymus and the adipose tissue of
Mediastinum and cervix with ectopic thymical focus ( Masaoki and
Jaretzki research)
Thymectomy from cervical access ( procedure of a limited completion)
 Thymectomy from longitudinal sternotomy ( good insight into the madiastinum,
disadvantage – extensive wound and operative shock)
 Maximal thymectomy from 2 accesses: cervical and through sternotomy
 Expanded cervical thymectomy according to Cooper ( application of
suspended surgical hook put on jugular incisure of sternum – better insight
into mediastinum)
 Maximal thymectomy from cervical-substernal-videothoracoscopic access (allows to remove thymus in a little invasive way without cutting
the sternum)
Thymomas – surgical treatment
 the best results in case of maximal expanded
thymectomy (complete operation) + radiotherapy of
mediastinum
 indicated even partial excision of thymomas
infiltrating neighboring organs (cytoredukctive
procedure) + radiotherapy + chemotherapy.
 prognosis depends on the type of proliferation (IoIVo).
 IIo i IIIo: 5-year survival in 23-54%.
COMPLICATIONS:
The most serious complication is respiratory insufficiency due to myasthenic crisis
( up to 20%), sporadically bleeding, infection and instability of sternum, paralysis of
phrenic and recurrent laryngeal nerve.
Operative access by longitudinal incision of the
sternum ( sternotomia longitudinalis) applied in
operative treatment of anterior mediastinum tumors
Thymectomy from longitudinal sternotomy
Medial longitudinal sternotomy as an operative access in
anterior mediastinum tumors
Germ-cell tumors
 the most frequently in young males,
 benign tumors: only surgical treatment,
 malignant tumors: treatment depends on diagnosis
( surgical treatment + combined treatment):
- carcinoma embryonale,
- teratocarcinoma,
- chorioncarcinoma.
In case of seminoma good results after radiotherapy
 neoplasmatic markers in treatment results monitoring
- HCG ( choriongonadothropin),
- AFP (alphafetoprotein)
Mesenchymal tumors
Tumors originating from connective tissue are:
- lipomas,
- fibromas,
- miomas,
- hemangiomas and lymphangiomas
- choristomas
- chondromas
- osteomas
Malignant forms of these tumors are rare.
Complete surgical excision of the tumor is a method of treatment.
Germ-cell tumors
These tumors include all germ layers’ tissues so their cells are able to
develop into different tissues and organs.
They are about 15% of mediastinal tumors.
The tumors are the most frequently solid or cystic and involve
different tissues inside (including: hair, teeth, cartilaginous and
osseous tissue and others).
These are:
 teratoma benignum
 teratoma malignum
 cystis dermoidalis
 teratocarcinoma
Complete surgical incision of the tumor is a method of treatment. In
case of malignant tumors we apply radio and chemotherapy.
Neoplasms from lympharic tissue
Lymphatic diseases are sometimes manifested as singular tumors in
anterior or medial mediastinum.
These include:




Hodgkin’s disease
Non-Hodgkin lymphomas
Lymphatic sarcomas
Castelman’s disease (hypertrophy of mediastinal lymphatic nodes)
Lymphomas are a contraindication to operative treatment.
If the diagnosis is correct the method of treatment is chemotherapy.
Mediastinal cysts
Mediastinal cysts are the effect of developmental disorders in the
prenatal period.
They are usually asymptomatic.
The forms of mediastinal cysts:




pericardial
bronchial
from alimentary tube
pseudocysts
Treatment involves surgical removal from sternotomy or
thoracotomy access, sometimes they can be removed by means of
less invasive methods (videothoracoscopy)
Definitions of ascending goitre in mediastinum
Retrosternal goitre: the type of goitre which reaches under the sternal manubrium
with its lower ends. It is an extrasternal extension of thyroid gland beginning on
the neck, where its blood vessels come from. It descends usually in front of
the trachea and the left brachiocephalic vein or laterally to the trachea, rarely
behind it and the esophagus. Approximately 10% cases may be located in the
posterior part of upper mediastinum, mainly on the right. The frequency of
occurrence is: 5%-29%.
Mediastinal goitre: it is a kind of goitre which descends its lower ends to the aortic
arch or lower, no matter where it starts. It has additional well developed vascular
supply in mediastinum. The frequency of occurrence: 0,5% - 3,5%
Ectopic goitre: ectopic thyroid tissue without connection to the right thyroid gland
Located in mediastinum or other parts of the chast having its own vessel supply.
Mediastinal goitre
In mediastinum we can find retrosternal,
mediastinal and ectopic goitre.

retrosternal goitre is usually removed from cervical access and
only 1-2% may require partial upper sternotomy,

in case of mediastinal goitre where lower ends descend under
the sternum sternotomy is necessary,

„Struma aberrans” – very rare, it is necessary to cut the
sternum.
Thyroid goitreis about 7% of mediastinal tumors. Malignant changes may occur in
about 5-15% cases of goitre located in mediastinum.
MEDIASTINAL EMPHYSEMA
Pneumomediastinum – mediastinal emphysema
(the presence of the air in the mediastinum)
Causes :
 oesephagus damage
 tracheal or bronchial damage
 complications of diseases leading to the damage of pulmona
tissue or the bronchial wall
 iatrogenic complication after diagnostic or therapeutical
puncture of mediastinal structures
MEDIASTINAL EMPHYSEMA
CLINICAL SYMPTOMS:
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pain located behind the sternum
dyspnoea
anxiety
cervical oedema
neck cracking while palpating
subcutaneous emphysema
tachypnoë
cyanosis
there may be symptoms of pneumothorax or heart
tamponade co-existing
MEDIASTINAL EMPHYSEMA
TREATMENT :
Tentative procedures:
 decompressing cervical mediastinotomy (incision
of mediastinum over jugular incision of sternum and
drainage)
 drainage of the pleural cavity with opening of the
mediastinum
Therapeutical procedures:
 debridement of the damage: trachea, bronchi, esophagus
 sometimes only mediastinal drainage in case of early
diagnosed small esophageal, tracheal or bronchial damages
MEDIASTINITIS
Mediastinitis an inflammatory state in loose tissues and mediastinal
spaces due to penetrating infection. Severe clinical course is loaded
with a high mortality rate.
Etiology of mediastinitis:
 injuries ( the most frequent cause)
 complications of surgical procedures
 inflammation descending along fascial spaces in purulent
states in oral cavity and neck (periodontal abscesses,
purulent tonsillitis, cervical abscesses)
 inflammation by circulatory or lymphatic route (rarely)
MEDIASTINITIS
DIVISIONS :
As for the part of mediastinum affected:
 Diffuse mediastinitis
 Limited mediastinitis
As for clinical course:
 Acute mediastinitis (mediastinitis acuta phlegmonosa)
 Mediastinal abscess (abscessus mediastini)
 Chronic unspecific mediastinitis
(mediastinitis chronica nonspecyfica)
 Chronic specific mediastinitis
(mediastinistis chronica specyfica)- in tuberculosis and
actinomycosis
MEDIASTINITIS
CLINICAL SYMPTOMS:
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pain behind the sternum
dyspnoe
mobile anxiety
leucocytosis
high temperature
cervical edema
neck cracking while palpating
subcutaneous emphysema
tachypnoë
cyanosis
symptoms of septic shock
MEDIASTINITIS
DIAGNOSIS :




clinical picture of mediastinitis
presence of purulent inflammation in cervix, oral cavity
widening of the mediastinal shade on the chest X-rays
leak of the contrast outside the esophagus in case of its
perforation
 identification of the place of esophagus perforation in
endoscopy
 visualization of the place of tracheal or bronchial damage
in bronchofiberoscopy
 presence of fistula in the bronchial stump after
pneumonectomy (bronchofiberoscopy)
MEDIASTINITIS
TREATMENT :
 wide spectrum or guided antibiotic therapy
 elimination of the cause of mediastinitis
(oesophageal perforatiorrhaphy or operative exclution of
oesophagus, maintenance of tracheal or bronchial damage,
incision and drainage of oral and cervical abscesses)
 effective mediastinal drainage from many access points
(cervical, infrasternal, by thoracotomy,
exstrapleurally from paravertebral access)
 best results when irrigation drainage applied (up-bottom
type) – antiseptic solution is given constantly through
drain put in the upper part of mediastinum and received
through drains in the bottom part of the pleural cavity and
under xiphoid process.