Disease of Mediastinum and Pleura Flashcards
What are the 3 compartments of the mediastinum?
Anterior (between sternum and pericardial sac)
Middle (from anterior pericardial sac to ventral surface of spine)
Posterior (spine and costovertebral gutters)
What resides in the anterior-superior compartment of the mediastinum? (5)
Thymus gland
Aortic root and great vessels
Substernal thyroid and parathyroid tissue
Lymphatic vessels and nodes
Inferior aspect of trachea and esophagus
What resides in the middle compartment of the mediastinum? (7)
- Pericardial sac
- Heart
- Innominate veins and SVC
- Trachea and major bronchi
- Hila
- Lymph nodes
- Phrenic, upper vagus, and recurrent laryngeal nerves
What resides in the posterior compartment of the mediastinum?
- Esophagus
- Descending aorta
- Azygous and hemiazygous veins
- Thoracic duct
- Lymph nodes
- Vagus nerves (lower portion)
- Sympathetic chains
Mediastinal masses can be organized in categories of _____ or _____, and ____ or _____.
Asymptomatic or symptomatic, benign or malignant
How are asymptomatic mediastinal masses found?
Incidental finding on imaging
What are the local and systemic symptoms of mediastinal masses?
Local symptoms: Compression or invasion of adjacent structures
Systemic symptoms: Fever, anorexia, weight loss (often lymph node related). Endocrine syndromes (thymus related). Autoimmune symptoms (thymus related)
____ percent of asymptomatic masses are benign
80%
____ percent of symptomatic masses are malignant
50%
In terms of mediastinal mass location, what is most common in adults vs. children?
Adults - anterior
Children - posterior
Are adults or children more symptomatic when it comes to mediastinal masses?
Children are more symptomatic (66%)
Adults (33%)
When evaluating for mediastinal mass, what are symptoms associated with obstructions of contiguous organs?
Dysphagia (compression of esophagus)
Hoarseness (compression of recurrent laryngeal nerve)
SVC syndrome (facial/upper extremity swelling from compression of superior vena cava)
Cough, stridor, hemoptysis, shortness of breath (compression of lungs)
Horner syndrome (sympathetic chain compression resulting in miosis (a constricted pupil), ptosis (a weak, droopy eyelid), apparent anhidrosis (decreased sweating))
What are B symptoms that can be seen with mediastinal masses? (3)
- Fevers
- Weight Loss
- Drenching night sweats
For mediastinal mass evaluation, what should be checked in physical exams?
- blood pressure
- weight loss
- lymphadenopathy
- Exam of head, neck, upper extremities, and chest
What imaging is done when evaluating for mediastinal mass?
CXR (PA and Lateral)
- to localize
CT Chest
- anatomic location
- differentiate between cyst vs solid lesions
- identify fatty structures
- lympadenopathy vs. vascular structures
Which compartment is the mediastinal mass in?
Anterior compartment.
What’s the differential diagnosis for an anterior compartment mediastinal mass? (7)
The 4 Terrible T’s is to help you remember the most common differential diagnosis for anterior compartment mediastinal masses.
- Thymic neoplasm
- Teratoma (germ cell tumor)
- (Terrible) Lymphoma (hogkin’s disease or non-hodgkin’s lymphoma)
- Thyroid neoplasm
And less commonly:
- Mesenchymal neoplasm
- Diaphragmatic hernia (Morgagni)
- Primary carcinoma
Which compartment is the mediastinal mass in?
Middle compartment.
20% of middle compartment mediastinal masses are due to ____
cysts
What is the differential diagnosis for middle compartment masses? (10)
- Lymphadenopathy
- Developmental cysts
- Reactive and granulomatous inflammation
- Metastasis (going to lymph nodes)
- Lymphoma
- Pericardial Cyst
- Bronchogenic Cyst
- Enteric Cyst
- Vascular Enlargements
- Diaphragmatic hernia (hiatal)
Which compartment is the mediastinal mass in?
Posterior compartment
What is the differential diagnosis for posterior compartment mediastinal masses? (9)
- Peripheral nerve (neurinomas)
- Neurogenic tumors
- Sympathetic ganglia
- Paraganglionic tissue
- Meningocoele
- Esophageal lesions
- Carcinoma
- Diverticuli
- Diaphragmatic hernia (Bochdalek)
What kind of mass would a CBC with differential help in diagnosing?
Helpful for diagnosing lymphoma
What kind of mass would beta-HCG and alpha-fetoprotein help in diagnosing?
B-HCG and a-fetoprotein are markers associated with germ cell tumors (e.g. teratoma)
What kind of mass would anti-acetylcholine receptor antibodies lab test be helpful in diagnosing?
Thymoma (thymus tumor)
What are 3 needle aspiration techniques that can be used to biopsy a mediastinal mass?
- Transbronchial Needle Aspiration (down the trachea and through the bronchial wall)
- Percutaneous Needle Aspiration (coming from outside of the chest cavity)
- Endoscopic ultrasound guided Aspiration (through esophagus or trachea)