Abstract
Headaches induced by mass effect are usually continuous; however, episodic, paroxysmal short-lasting headache associated with a mass has rarely been described (1, 2). We report a patient with nasopharyngeal cancer who presented with a paroxysmal headache that was concurrent with a cough.
Case report
A 56-year-old man was admitted to our hospital for an intractable episodic headache, which began approximately 40 days prior to admission. The headache was located in the left frontotemporal area, and occurred 5–10 times a day with duration of 20 min. The explosive cough began simultaneously with the onset of his headache. He also exhibited aspiration of saliva during the headache and cough. The headache and cough ceased abruptly and concurrently. The pain was dull and aching in nature and severe enough to interrupt sleep. He also complained of nausea, blurred vision, dysphagia, and left lateral neck pain. However, he did not note any autonomic symptoms such as eye injection, lacrimation, rhinorrhea, nasal stiffness or eyelid oedema, nor photophobia/phonophobia. No specific triggering factor or preferred time of occurrence was found.
Neurological examination revealed left ptosis without anhydrosis. The pupil could not be evaluated because of a left iridocorneal adhesion due to trauma during childhood. The left soft palate elevation was mildly impaired, but there was no dysarthria or tongue deviation. The strength of the sternocleidomastoid and trapezius muscles was normal. A fixed tender palpable mass was found in the left submandibular area. He had a history of smoking 1.5 packs of cigarettes per day for 30 years and he quit smoking 2 years prior to the onset of the headaches. He was diagnosed with hypopharyngeal cancer in the left pyriform sinus with retropharyngeal node enlargement without distant metastasis 2 years prior to the visit. An excisional operation was performed at that time followed by radiation therapy and chemotherapy. Follow-up neck CTs, which were performed regularly, revealed no evidence of cancer recurrence and markedly reduced sizes of residual nodes.
A nasopharyngeal MRI performed upon admission (Figure 1) showed that the primary cancer site was stable; however, two newly developed mass lesions were found. The masses particularly encased the left internal carotid artery of the neck. The oncologic work-up revealed a metastatic mass in the lung.
Nasopharyngeal MRI of a 56-year-old man who presented with a paroxysmal cough and left unilateral headache. Metastatic lymph node enlargement due to hypopharyngeal cancer is shown in the left cervical area. The mass encased the internal carotid artery and surrounding lower cranial nerves and sympathetic chain.
Simple painkillers were not effective for treating the headache. An indomethacin trial (100 mg per day) for exclusion of an indomethacin-responsive headache also failed due to severe epigastric discomfort without response. Combination therapy with dexamethasone, codein and morphine was only transiently effective at treating both the headache and cough. Although palliative radiation and chemotherapy continued, lower cranial nerve signs such as throat pain, difficulty swallowing, ipsilateral facial palsy and vocal cord palsy were newly developed and progressed. The severe headache continued in spite of treatment and he died due to aspiration pneumonia.
Discussion
Our patient initially had a short-lasting paroxysmal hemicrania that concurred with a paroxysmal cough without autonomic symptoms. He had an underlying pathology of nasopharyngeal cancer. The well-known type of headache associated with cough is called a ‘cough headache’. However, the clinical characteristics of the cough headaches did not match well with our patient's symptoms. A cough headache is described as a ‘sudden onset, lasting from one second to 30 min, brought on by and occurring only in association with coughing, straining and/or Valsalva maneuver’ according to the ICHD-2 criteria (3). A cough is a triggering or precipitating factor in the case of a cough headache; however, the cough in this presenting patient concurrently developed with paroxysmal headache and disappeared when the headache was resolved.
The unilateral occurrence of a headache is another different characteristic from common symptomatic cough headache and it is more similar to paroxysmal hemicranias, such as chronic paroxysmal hemicrania or SUNCT (subacute unilateral neuralgiform headache with conjunctival injection and tearing) (4, 5). Arnold-Chiari malformation type I, which is the most common cause of symptomatic cough headache, usually develops in bilateral headaches (6). A unilateral cough headache, as in the case of our patient, has rarely been reported in patients with carotid artery stenosis (7, 8) and an aneurysm at the junction of the posterior communicating artery and the internal carotid artery (9).
The mechanism underlying cough headaches remains obscure. It seems intuitive that it would be associated with increased intracranial pressure (6). Cough, lifting and straining induces increased intrathoracic and intra-abdominal pressure and finally results in increased intracranial pressure. The other suspected mechanisms underlying cough headache include the stretching of a pain-sensitive structure within the posterior fossa (10), craniospinal pressure dissociation (11), heightened receptor sensitivity (12), altered vascular tone in the head by systemic infection (13), sudden increment in intracranial venous pressure (14), CSF hypervolemia (15), incompetent or absent jugular venous valves (16), and low CSF pressure (17). Concurrent development of a cough and hemicrania in our case indicated no causal relationship between the cough and the headache; therefore, the aforementioned hypothesis could not be applied to our case. The neck mass might cause both symptoms concurrently by the direct stimulation of pain-sensitive structures. The most plausible candidate structure in the patient is the vagus nerve. It is well known that the direct stimulation of the vagus nerve induces paroxysmal cough (18). One of the most common complications following vagus nerve stimulation in patients with epilepsy is a cough, which is reduced by decreasing the stimulation intensity. Moreover, the vagus nerve contains a pain-sensitive neural fibre. Although the patient did not have any autonomic symptoms or signs related to vagal stimulation, the patient's neck mass probably stimulated the vagus nerve, resulting in the concurrent development of hemicrania and cough.
In summary, our patient had a paroxysmal cough and short-lasting hemicrania, which may have been induced by the direct stimulation of the vagus nerve by a metastatic mass lesion encasing the internal carotid artery and vagus nerve.