Osteogenic factor Bmp2 may play an important role in the calcification of adamantinomatous craniopharyngioma ACP via autocrine or paracrine mechanisms. Given the presence of osteogenic markers (Runx2 and Osterix), craniopharyngioma cells could differentiate into an osteoblast-like lineage, and the process of craniopharyngioma calcification resembles that which occurs in osteogenesis/odontogenesis 1).
Radiographic detection of calcification in pituitary adenoma is relatively rare, and the clinical characteristics of pituitary adenoma with calcification remain unclear.
A total of 160 patients who underwent surgical resection of pituitary adenomas between February 2004 and December 2016 were reviewed. Eighty-one patients had hormone-secreting pituitary adenomas, and 79 patients had nonfunctioning pituitary adenoma. Among these 160 patients, cases with radiological calcifications on preoperative neuroimaging were included in this study, and clinical characteristics with intraoperative findings were analyzed, retrospectively.
Pituitary adenoma with calcification on preoperative neuroimaging was observed in only nine cases (5.6%). The study population consisted of these nine patients with nonfunctioning pituitary adenoma (n = 5), mixed growth hormone and prolactin-secreting pituitary adenomas (n = 3), and a prolactinoma (n = 1). In 89% of cases (n = 8), calcified pituitary adenoma was soft enough for suction despite the presence of a granular gritty texture intraoperatively. Besides, in a single patient (11%), evidence of hard thick capsular calcification was seen surrounding a soft tumor component; however, it did not interfere with adequate removal of the soft part, and tumor resection was possible in all cases without any complications.
Pituitary adenoma presenting with calcification is relatively rare, but should be kept in mind to avoid making a wrong preoperative diagnosis. As not all pituitary adenomas with calcification are hard tumors, preoperative radiological calcification should not affect decision-making regarding surgical indications 2).
Dementia associated with brain calcification may occur in Down syndrome and some cases of Fahr’s disease (bilateral striatopallidodentate calcinosis). Basal ganglia calcification may occur in Nasu–Hakola disease resulting from TREM2 mutations, and punctate calcification of subcortical and deep white matter may occur in adult-onset leukodystrophy with axonal spheroids and pigmented glia resulting from CSF1R mutations. Brain calcification in hypoparathyroidism or pseudohypoparathyroidism may occasionally be associated with cognitive impairment. All these diagnostic possibilities were excluded by the clinical and investigation findings.
Chance concurrence of two separate disorders (dual pathology), FTD and idiopathic brain calcification, might explain this case. However, a plausible unifying diagnosis for this phenotype is Kosaka–Shibayama disease, or diffuse neurofibrillary tangles with calcification (DNTC). This rare disorder of unknown aetiology is reported almost exclusively from Japan 3).