Pancoast Syndrome Characteristics
The correct answer is D (or E, as they are identical): Only B and C are correct. Pancoast syndrome results from superior sulcus tumors located in the apex of the lung—not the right middle lobe—and characteristically involves the C8, T1, and T2 nerve roots with shoulder pain radiating in an ulnar distribution 1, 2.
Anatomic Location and Pathophysiology
Pancoast tumors arise in the apical lung, not the right middle lobe, making statement A incorrect 2, 3. These tumors:
- Are defined as lung cancers arising in the apical lung that invade thoracic wall structures at the level of the first rib or above 2
- Frequently invade the brachial plexus, subclavian vessels, or spine through direct tissue contiguity 3
- Account for less than 5% of all bronchogenic carcinomas 3
Nerve Root Involvement
Statement B is partially correct but imprecisely worded. The syndrome involves:
- The eighth cervical (C8) and first and second thoracic (T1, T2) nerve roots—not "right cervical" nerves 1
- The lower portion of the brachial plexus through direct invasion 1, 3
- The stellate ganglion and paravertebral sympathetic chain 4
The term "right cervical" in option B is anatomically imprecise, though the intent to reference C8-T2 nerve roots is correct 1.
Clinical Presentation
Statement C is correct. The characteristic presentation includes 1, 2:
- Shoulder pain radiating along the ulnar distribution of the arm and hand (medial forearm and hand)
- Pain radiating toward the axilla and scapula 3
- Weakness and atrophy of hand and arm muscles, particularly the hypothenar eminence 5
- Paresthesias in the C8-T1 distribution 1
Complete Pancoast-Tobias Syndrome
The full syndrome encompasses 1, 3:
- Horner syndrome (unilateral ptosis, miosis, and anhidrosis) from stellate ganglion infiltration
- Severe shoulder and arm pain from brachial plexus invasion
- Neurological deficits in the ulnar nerve distribution
- Weakness and muscle atrophy of the hand
Key Clinical Pitfall
Respiratory symptoms are often completely absent because of the peripheral location of these tumors 1. The distribution of pain outside the chest frequently delays consideration of lung cancer as the primary etiology 1. Many patients are initially misdiagnosed and treated for osteoarthritis due to the predominant shoulder pain 6.
Diagnostic Approach
When Pancoast syndrome is suspected 1, 2:
- Obtain tissue diagnosis via CT-guided transthoracic needle biopsy before initiating treatment
- Perform MRI of the thoracic inlet and brachial plexus to characterize vascular and neural invasion
- Complete mediastinal staging and extrathoracic imaging (brain CT/MRI plus PET or abdominal CT plus bone scan)