Giant calcified pseudoplasm of the nerve axis of the temporal lobe: a case report and review of the literature

Calcifying pseudoneoplasms of the neuraxis (CAPNONs) are rare and can occur along the neural axis. The pathogenesis of these masses is still unknown, and they are diagnosed by histopathological analysis. We report the largest CAPNON in the temporal lobe reported to date and a review of the literature on all previously reported CAPNON cases located in the temporal lobe. According to the literature review, prior to 2020, the largest CAPNON in the temporal lobe that had ever been reported measured 30 × 30 × 20 mm (Mohapatra et al.). However, we report a larger temporal lobe CAPNON (45 × 35 × 35 mm) in a female patient admitted to our hospital. In addition, among 22 patients with CAPNONs aged from 6 to 62 years, 45.5% were female and 54.5% were male. A total of 72.8% of patients presented with seizures, 9.1% had pituitary dysfunction and 9.1% did not have symptoms. Of the cases in the patients with seizures, 83.2% were completely surgically resected, 5.6% were partially surgically resected, and one was treated medically; one patient refused treatment. Except for one patient who had multiple lesions, all patients who underwent surgery exhibited improved or the disappearance of symptoms of epilepsy. The patient in whom epilepsy resolved had undergone total resection. CAPNON is a rare benign lesion that occurs throughout the nervous system, and the pathogenesis remains unclear. Although the hardness of these lesions vary, surgery is still the preferred treatment and yields good results, and total resection is recommended for patients with epilepsy in the temporal lobe.