Background: Carcinoids are neuroendocrine tumors involving the
gastrointestinal tract, lungs and bronchi. They are usually benign with slow
growth, but they can be malignant (metastasizing to liver, lungs, bones,
skin, etc). Endocrine activity results in carcinoid syndrome: Intestinal
carcinoid [5-hydroxytryptamine (serotonin) to portal circulation]:
abdominal cramps, diarrhoea, bronchospasm, face/chest cyanotic flushes,
right-sided stenotic cardiac lesions. Lung carcinoid (histamine and
5-hydroxytryptophan to systemic circulation): red facial flush/oedema,
salivation, lachrymation, potentially tachycardia, fever, anxiety, tremor,
hypotension, left-sided cardiac lesions). We present an extremely rare case
of primary lung carcinoid presented with paraparesis.
Patient and methods: A 69 year old man developed progressively
deteriorating bilateral proximal muscular weakness of the legs that
within 6 months led to paraparesis (inability to stand up and walk) with
preserved sensation. Electromyography showed polyneuropathy. History,
clinical and laboratory data excluded diabetis mellitus, hypothyroidism,
renal/liver failure, cachexia, alcohol abuse, chemotherapy, drug or other
toxicity. Magnetic resonance imaging excluded spinal cord or spinal nerve
root compression. Computed tomography revealed a small peripheral
paracardiac right-middle lobe tumor (maximal diameter:1.8cm).
Thoracoscopic wedged resection was performed (endo-stappler).
Histology revealed lung carcinoid of low mitotic index (1-2%).
Results: The patient had an uneventful recovery, was discharged on
the 5th postoperative day to a rehabilitation centre, where he remained
for 3 months. Progressive motor function improvement was noted;
paraparesis resolved completely within 6 months. At 1-year follow-up
normal respiratory and neurological status was noted, in the absence of
carcinoid recurrence or metastasis.
Conclusions: Myopathy is common in endocrine disease and cancer
can have endocrine and metabolic activities and cause neurological
complications. Encephalopathy, myelopathy, and more often motor and
sensory neuropathy, myopathy, or neuromyopathy of central distribution
may occur in paraneoplastic syndromes. Neuromyopathy has been reported
in 14% of lung cancer patients. There are reports of recurrent facial palsy
in metastatic thymic carcinoid, proximal muscle weakness in ACTHreleasing
thymic carcinoid, an ACTH-releasing bronchial carcinoid, and
paraparesis 40 years after pneumonectomy for carcinoid adenoma induced
by inflammatory contents of the pneumonectomy cavity. To the best of our
knowledge there is no report of paraparesis induced by primary pulmonary
carcinoid. Complete resolution after excision suggests “paraneoplastic”