The High Coast of Smoking: An Interesting Case of Pancoast Syndrome

CASE

A 52 year-old male presented to the emergency department with a chief complaint of right shoulder pain. In fact, the patient endorsed several years of shoulder pain, which he attributed to being right hand dominant, and the physical demands of his work as a contractor. One month prior to his presentation, the patient had also seen an orthopedic surgeon, who diagnosed him with a paralabral cyst, and subsequently drained it. After the procedure, the patient’s pain improved, but the effect was short lived.

Upon arrival, the patient complained of 10/10 pain in his right shoulder that radiated to his elbow. He described the pain as not only “dull,” but also “sharp” and “stabbing.” He had no relief with home ibuprofen or diazepam, which had been prescribed by the orthopedic surgeon. Any movement of the arm made the pain worse.

There was no significant family history of medical problems. The patient endorsed a 40 pack year history and daily marijuana use, but denied IV drug use.

Vital signs were normal. Physical exam was significant for tenderness to palpation over the right deltoid and trapezius. There was also noticeable atrophy of the deltoid and bicep. Interestingly, during the course of the musculoskeletal exam, the patient was noted to have ptosis of the right eye, as well as anisocoria, with his right pupil measuring 2 mm and the left pupil measuring 4 mm. A complete neurologic exam was done, which showed 4/5 strength throughout the right arm, but was otherwise reassuring. The patient had normal cardiovascular and abdominal exams.

Laboratory testing, including a CBC, CMP, ESR, CRP, coagulation studies, and a troponin were within normal limits.

A chest x-ray was performed and read as no acute cardiopulmonary process. Given the patient’s neurologic symptoms, a CTA of the neck was performed. This study showed a left ICA bulb, but no other acute findings that could explain the patient’s symptoms. An MRI of the C-spine was then performed:

Figure 1. MRI showing paraspinous soft tissue mass.

The MRI showed a right-sided infiltrative paraspinous soft tissue mass, which involved the vertebral bodies at C7 through T4, including neural foraminal infiltration at those levels.

DIAGNOSIS

Horner syndrome, secondary to malignancy with high suspicion for Pancoast tumor.

DISCUSSION

Horner Syndrome

Horner syndrome is the triad of unilateral miosis, ptosis, and anhidrosis; however, the anhidrosis is often not apparent to both the clinician and the patient. Horner syndrome is caused by injury to the sympathetic chain, a paired bundle of nerve fibers that run from the skull to the coccyx, just lateral to the vertebral bodies. It provides autonomic innervation to the organs, as well as the structures of the eye, hence the observed ptosis and miosis.[1]

In fact, there are three types of Horner syndrome: central, preganglionic, and postganglionic. Central lesions affect the sympathetic tracts of the brainstem or cervicothoracic spinal cord, and may be the result of trauma, strokes, tumors, or demyelinating diseases. Preganglionic lesions affect the spinal cord, thoracic outlet, or lung apex, often due to trauma, surgery, or malignancy. Postganglionic lesions often affect the internal carotid artery, and can be due to dissection, thrombosis, or iatrogenic (caused by endarterectomy or stenting, for example).[1]

Importantly, when Horner syndrome is present, other concurrent neurologic symptoms may be useful in localizing the location of the pathologic lesion. Diplopia, vertigo, and ataxia are suggestive of a brainstem lesion, whereas weakness, a sensory level, or bowel or bladder impairment portend cervicothoracic cord involvement. Pathology affecting the brachial plexus, often arising in the lung apex, can cause arm pain and weakness. Associated extraocular muscle paresis raises concern for cavernous sinus involvement. Isolated head or neck pain in the setting of Horner syndrome suggests carotid dissection.[1]

In this case, the patient had pain, weakness, and atrophy of his right arm, but no signs or symptoms concerning for a brainstem, cavernous sinus, or carotid lesion. In a patient with a 40 pack-year smoking history, presenting with Horner syndrome and symptoms concerning for cervicothoracic cord and brachial plexus involvement, a Pancoast tumor affecting the lung apex is a significant concern.

Pancoast Tumor

A Pancoast tumor is a tumor of the pulmonary apex. They are most often non-small cell cancers, either squamous cell or adenocarcinoma, and have a significant predilection to spread to surrounding tissues, such as the ribs or vertebrae.[2,3]

Figure 2. Anatomy of a Pancoast (superior sulcus) tumor. (Physiopedia; physio-pedia.com)

In fact, Pancoast tumors that invade the brachial plexus may result in Pancoast syndrome, which includes arm pain, weakness, and paresthesias, most commonly in the ulnar distribution, as well as Horner syndrome due to invasion of the stellate ganglion.[2]

If suspected, a chest x-ray is often the first step in diagnosis, although the sensitivity is low. If present, a Pancoast tumor may appear as a subtle soft tissue mass. CT scan is the primary modality for diagnosis, being very sensitive for identification of lung lesions. MRI, however, provides the best assessment of soft tissue involvement, as well as extension into the vertebral bodies, neural foramina, and spinal cord.[3-5]

CASE RESOLUTION

This patient was admitted to the hospital, and a biopsy performed two days later confirmed a diagnosis of non-small cell lung cancer. His hospital course was complicated by pneumonia, but he was discharged eight days later after initiating treatment. He was readmitted one month later with multiple pulmonary emboli, but was again discharged with oncology follow-up. He has been followed closely by oncology and palliative care.

TAKE-AWAYS

Horner syndrome is the combination of unilateral ptosis, miosis, and anhidrosis.
Careful assessment of other neurologic deficits may assist in localization of the lesion responsible for the Horner’s syndrome, and inform the subsequent imaging strategy.
CT scans are sensitive for lung lesions, but MRI is better for evaluation of the soft tissues, as well as vertebral, foraminal, and spinal cord involvement.

FACULTY REVIEWER

Dr. Gita Pensa

REFERENCES

Kedar S, Biousse V, Newman NJ. Horner Syndrome. Wilterdink JL (Ed.), UpToDate. Updated June 19, 2018. Accessed August 18, 2019.
Bruzzi JF, Komaki, R, Walsh GL et al. Imaging of non-small cell lung cancer of the superior sulcus: part 1: anatomy, clinical manifestations, and management. Radiographics. 2008; 28(2): 551-60.
Villgran VD, Cherian SV. Pancoast Syndrome. StatPearls. Updated March 3, 2019. Accessed August 23, 2019.
Bruzzi JF, Komaki, R, Walsh GL et al. Imaging of non-small cell lung cancer of the superior sulcus: part 2: initial staging and assessment of resectability and therapeutic response. Radiographics. 2008; 28(2): 561-72.
Manenti G, Raguso M, D’Onofrio S et al. Pancoast Tumor: The Role of Magnetic Resonance Imaging. Case Rep Radiol. 2013. DOI: 10.1155/2013/479120.