Dural metastasis of nasopharyngeal carcinoma: rare, but worth considering

Abstract

Metastasis of nasopharyngeal carcinoma (NPC) to the dura, an extremely rare condition, can be symptomatically silent and mistaken for a benign entity radiographically. Missed diagnosis can lead to serious consequences or prove immediately fatal. We report a woman with dural metastasis of NPC that mimicked a meningioma on radiography. Craniectomy with tumour resection was performed due to rapid progression from the onset of symptoms to disability. The patient was still alive two years after surgery. This case emphasises the need to keep in mind the possibility of dural metastasis of NPC in patients with abnormal imaging features. This would not only avoid wrong and optimistic diagnosis, but also allow for appropriate treatment in a timely manner. To our knowledge, this is the first report of metastasis of NPC to the dura. We provide detailed information on the neoplastic lesion, which masqueraded as a benign entity and caused potentially fatal consequences. NPC has a propensity to develop distant metastases, with an incidence of 17%-53%, and its most common metastatic sites are the bones, lungs and liver.(3) Intracranial metastases, found in 25% of patients with malignancies, may be categorised by location as skull, dural, leptomeningeal and brain metastases. The diagnostic challenge presented by dural metastasis of NPC is not only associated with the rarity of dural metastasis from NPC but also because dural metastases can be mistaken for a benign entity both clinically and radiographically. Clinically, about 20% of dural metastases are symptomatically silent and discovered incidentally on radiological workup. (7) Radiographically, although MR imaging is useful in differentiating malignant soft-tissue tumours from benign ones, dural metastases can be mistaken for benign meningiomas that typically have a ragged border, (9) due to identical dural tail signs on MR imaging. (4) As disease progression is rapid, delayed diagnosis of dural metastasis of NPC also means that it might not be possible to perform appropriate surgical intervention in these patients in a timely manner.With the dural tail sign on follow-up MR imaging as the only clinical indicator, dural metastasis from NPC was not identified early in our patient, causing an increase in intracranial pressure and subsequent neurological complications. Although the missed diagnosis may have led to fatal consequences, tragedy was narrowly avoided in our patient through prompt treatment (i.e. craniectomy and tumour resection).In conclusion, this report highlights the diagnostic and assessment difficulties clinicians face when dealing with patients diagnosed with NPC following treatment. Clinicians need to maintain a high index of suspicion for dural metastasis in these patients when evidence such as the dural tail sign on repeat MR imaging is present. We recommend that a diagnosis of benign dural lesion be made only if a malignant lesion is excluded. R E FE R E N CE S

Long‐term recurrence and brain metastasis of nasopharyngeal carcinoma mimicking cystic radiation encephalopathy relapse: a case report

“…It is rare for NPC to metastasize to the brain through blood or cerebrospinal fluid circulation. A PubMed search revealed only a few well-described relevant cases that did not include spinal metastasis (Table 1 [5,[8][9][10][11][12]). Perhaps due to the effect of the blood-brain-barrier, the brain is not a typical site for metastasis of NPC [12].…”

Brain and frontal‐bone metastasis from nasopharyngeal carcinoma: Case report and literature review

“…A PubMed search revealed only a few well-described relevant cases and did not include spinal involvement or direct intracranial invasion. [24][25][26][27][28][29][30][31] Only brain metastasis, with/without common metastasis sites, was reported. Only two case studies have discussed isolated brain metastasis from NPC.…”

“…Kuo and colleagues reported a patient with NPC with an isolated metastasis of the frontotemporal lobe observed 2 months after completion of treatment to the primary tumor. 31 Immediate craniectomy with tumor resection was undertaken for that patient. Histopathology of the tumor revealed a differentiated nonkeratinizing carcinoma.…”

“…The blood‐brain barrier stops entry of some chemotherapy drugs. A PubMed search revealed only a few well‐described relevant cases and did not include spinal involvement or direct intracranial invasion . Only brain metastasis, with/without common metastasis sites, was reported.…”

Symptoms, warning signs, and lifestyle choices associated with head and neck cancer

“…The incidence rate of nasopharyngeal cancer in men in Taiwan is more than 10 times higher than that of men in the US and more than 20 times higher than that of men in Japan. Nasopharyngeal cancer is most prevalent in patients between the age of 40 and 50 and is more common in men than in women by a ratio of 3 to 1 [12]. The most common symptoms of nasopharyngeal cancer are neck masses.…”