A Case of Godtfredsen Syndrome due to Nasopharyngeal Cancer Presenting as Sixth and Twelfth Nerve Palsies

Purpose: We present a case of Godtfredsen syndrome, characterized by concurrent sixth and twelfth cranial nerve palsies, in a patient with nasopharyngeal cancer.Case summary: A 74-year-old male with diplopia and headache with a duration of 3 weeks reported a weight loss of 4 kg over the preceding month. His history included smoking and moderate alcohol consumption. Ophthalmologic examination revealed esotropia with a 50 prism diopter deviation in both distant and near vision, identified through an alternating prism cover test. Additionally, a left abduction deficit was noted on duction and version tests. Cranial nerve assessment indicated tongue deviation to the left. Fundus examination and spectral-domain optical coherence tomography of the retina and optic nerve showed no abnormalities. However, a 2.3 cm mass in the left nasopharyngeal region, extending to the clivus, was detected on orbital magnetic resonance imaging. Biopsy confirmed nasopharyngeal cancer and chemotherapy was initiated.Conclusions: Godtfredsen syndrome is accompanied by paralysis of the 6th cranial nerve and ipsilateral 12th cranial nerve. This syndrome must be distinguished from isolated paralysis of the 6th cranial nerve or restricted strabismus featuring an abduction disorder. Since Godtfredsen syndrome is primarily caused by a tumor invading the clivus, patients with suspected paralysis of the 6th cranial nerve should undergo a comprehensive health assessment and a wide-ranging cranial nerve examination to allow timely identification of the tumor and prompt treatment.