A Man With Lymphoma and Numbness in the Fingers of One Hand

A 52-year-old man with a history of non-Hodgkin’s lymphoma presented with pain of 1-month duration in the left chest that radiated to the arm with intermittent numbness in the left two fingers.

He drank approximately six beers per week and smoked one pack of cigarettes per day. Past medical history was unremarkable.

Neurologic examination revealed normal mentation and cranial nerves, except for slight droopiness of the left eyelid, and the left pupil was smaller than the right ( Fig. 12-1 ). Both pupils were reactive to light and accommodation. There was decreased sweat in the left hemiface. Extraocular movements and other cranial nerves were normal. He had weakness of the interossei muscles in the left hand and mild weakness of the thenar and finger extensor muscles of the left. There was also left interossei atrophy. No fasciculations were detected. Reflexes were equal in the arms and legs at about 1 to 2+. There were no Babinski signs. There was mildly decreased vibration sense in the toes, decreased pain sensation and two-point discrimination in the last two fingers and dorsum of the left hand, and some questionable decreased pain sensation in the inner forearm. Adson’s maneuver was negative. Coordination was normal.

What is the Differential Diagnosis?

This patient’s symptoms and clinical findings indicate a mild polyneuropathy and a focal disorder involving muscles innervated by C8 and T1 roots through the ulnar, median, and also apparently the radial nerves on the left.

The sensory findings are also suggestive of a C8 and T1 radiculopathy or a lesion in the medial cord or lower trunk of the brachial plexus. The eye findings indicate Horner syndrome, characterized by ptosis, myosis, and anhidrosis from the involvement of the sympathetic ganglia or the T1 root. The sympathetic fibers that dilate the pupils originate in the hypothalamus, extend to the spinal cord, and then exit to the sympathetic ganglia. Thereafter, they run in the wall of the carotid artery and go through the cavernous sinus and the superior orbital fissure ( Fig. 12-2 ). The parasympathetic fibers that direct the constriction of the pupil travel via the third cranial nerve.

An EMG Test was Performed

Motor Nerve Studies

Nerve and Site	Latency(ms)	Amplitude (mV)	Conduction Velocity (m/s)
Median Nerve L.	Normal ≤ 4.2	Normal ≥ 6	Normal ≥ 50
Wrist	3.7	10	–
Elbow	8.3	10	53

Ulnar Nerve L.	Normal ≤ 3.6	Normal ≥ 8	Normal ≥ 50
Wrist	2.9	9	–
Below elbow	7.7	8	51
Above elbow	9.7	8	60
Axilla	13.2	8	52
Erb’s point	17.6	7	42

Nerve and Site	Latency (ms)	Amplitude (mV)	Conduction Velocity (m/s)
Ulnar Nerve R.	Normal ≤ 3.6	Normal ≥ 8	Normal ≥ 50
Wrist	2.8	10	52
Below elbow	7.6	10	52
Above elbow	9.6	10	59
Axilla	13.0	10	53
Erb’s point	15.0	9	60

F-Wave Studies

Nerve	Latency (ms)	Normal Latency ≤ (ms)
Median nerve L.	29.8	30
Ulnar nerve L.	32.0	30
Ulnar nerve R.	28.8	30

Sensory Nerve Studies

Nerve	Onset Latency (ms)	Normal Onset Latency ≤ (ms)	Peak Latency (ms)	Normal Peak Latency ≤ (ms)	Amp (μV)	Normal Amp ≥ (μm)	Conduction Velocity (m/s)	Normal Conduction Velocity ≥ (m/s)
Median nerve L.	2.5	2.6	3.0	3.1	40	20	52	50
Ulnar nerve fifth digit L.	2.3	2.6	2.8	3.1	8	13	52	50
Dorsal ulnar cutaneous L.	1.7	1.8	2.2	2.3	4	12	59	50
Medial ante. cutaneous L.	^a	^a	2.8	2.6	6	12	^a	^a
Ulnar nerve fifth digit R.	2.4	2.6	2.9	3.1	18	13	50	50
Dorsal ulnar cutaneous R.	1.7	1.8	2.2	2.3	15	12	59	50
Medial ante. cutaneous R.	^a	^a	2.2	2.6	14	12	^a	^a