What is the most likely explanation for his symptoms?

Author

Dr. Shoaib Ahmad Baig
December 30, 2024

🔍 Question of the day

A 69-year-old man presents with worsening pain under his right scapula and along his right arm for several months, which now disrupts his sleep. The pain is accompanied by numbness in his right forearm, extending to the fourth and fifth fingers. He also reports a persistent dry cough, recently with blood-streaked sputum. His medical history includes hypertension, gastroesophageal reflux disease, and osteoarthritis. He has a significant smoking history, consuming two packs daily for over 40 years, though he has recently reduced to a few cigarettes daily.

What is the most likely explanation for his symptoms?

A. Abnormal hormone secretion

B. Airway obstruction

C. Anterior mediastinum mass

D. Autoimmune disease

E. Pericardial effusion

F. Pleural effusion

G. Superior sulcus tumor

Correct Answer 🎯: G. Superior sulcus tumor

⚙️

Long History of Smoking (2 packs/day for 40+ years)

⬇

Chronic exposure to carcinogens

⬇

↑ Risk of bronchogenic carcinoma (e.g., superior sulcus tumor)

Superior Sulcus Tumor (Pancoast tumor) 🧠

⬇

Compression/Invasion of:

• Brachial plexus (C8-T1 roots)

⬇

Nerve compression

⬇

• Pain beneath right scapula → radiates to right arm

• Numbness → 4th & 5th fingers

⬇

Motor and sensory nerve dysfunction

• Sympathetic chain involvement

⬇

May lead to Horner’s syndrome (not noted in this patient but possible):

• Ptosis

• Miosis

• Anhidrosis

Persistent Nonproductive Cough + Hemoptysis

⬇

Tumor invasion into bronchial structures

⬇

• Bronchial irritation

• Vascular invasion → Hemoptysis (streaks of blood)

How Symptoms Work 🪛 

Tumor Compression/Spread → ⚖️ Compare Differential Pathways

• Brachial Plexus (C8-T1) 🧠

Tumor compresses nerves ⬇

⚙️ Neuropathic effects:

• Pain beneath scapula → arm.

• Numbness in 4th/5th fingers.

• Bronchial Structures

Tumor irritates airways ⬇

⚙️ Local effects:

• Persistent cough.

• Hemoptysis (streaks of blood) due to vascular invasion.

• Sympathetic Chain

⚙️ Potential spread:

• Horner’s syndrome (ptosis, miosis, anhidrosis) if chain affected (absent here).

How To Approach this Question? 🏗️

• Key Clues 🧠:

• Chronic smoker (2 packs/day for 40+ years).

• Pain and sensory changes localize to brachial plexus (C8-T1 roots).

• Hemoptysis → suggestive of malignancy.

⚖️ Explanation of Other Differentials

Differential ⚖️

Mechanism ⚙️

Why Incorrect? 🔴

Abnormal Hormone Secretion

Paraneoplastic syndromes = systemic effects (e.g., Cushing’s).

No localized nerve compression as seen here.

Airway Obstruction

Expect dyspnea, wheezing

Not nerve dysfunction.

Anterior Mediastinum Mass

Think thymomas 🪙 (immune effects like myasthenia gravis)

Not brachial plexus involvement.

Autoimmune Disease

Typically systemic (rash, joint issues)

Not focused nerve symptoms.

Pericardial Effusion

Expect signs of tamponade (hypotension, muffled sounds)

Not hemoptysis or nerve issues.

Pleural Effusion

Presents with dyspnea, decreased breath sounds

Not neuropathic pain.

📝 Flashcards

Stay Hungry, Stay Curious!

Your Brother In This Struggle

Dr. Shoaib Ahmad

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