[Classification of Clinical Syndromes Associated with Skull-Base Metastasis in the MR Era]

Abstract

Background: Skull-base metastases frequently cause progressive ipsilateral disturbances of cranial nerves or pain, resulting in poor quality of life in patients with cancer. Magnetic resonance(MR)imaging is the method to detect skull-base metastases, which demonstrates focal lesions of low-intensity signal and enhancement on T1-weighted MR images.

Methods: We reviewed clinical data and MR images from 127 patients with skull-base metastases diagnosed at Shizuoka Cancer Center Hospital between August 2012 and November 2017.

Results: The most common primary site was the lung(44 patients), followed by the breast(34), colon(8), and prostate(8). The interval from diagnosis of the primary tumor to skull-base metastasis ranged from 0 to 276 months(median, 9 months). The interval was shortest with lung cancer(median, 0 month), and longest with carcinoma of the liver(median, 81 months). The most commonly affected site was the clivus(74%), followed by the petrous(35%), and the occipital condyle(18%). We classified 55 symptomatic patients into 6 clinical syndromes: orbital(18%), parasellar(7%), middle cranial fossa(24%), jugular foramen(7%), and occipital condyle(15%), described by Greenberg, and a new entity "clivopetrosal" syndrome presenting diplopia due to abducens palsy(20%). Of 47 patients who underwent irradiation, 29 patients(62%)achieved relief of their symptoms. Median overall survival after diagnosis of a skull-base metastasis was 7 months. Male sex and colon cancer were associated with poor prognosis.

Conclusion: When a cancer patient presents with new-onset cranial nerve palsies or craniofacial pain, physicians need to identify skull-base metastases for prompt radiotherapy.