Case ReportRathke Cleft Cyst with Entirely Ossified Cyst Wall and Partially Solid Cyst Content: A Case Report and Literature Review
Introduction
Rathke cleft cysts (RCCs) are non-neoplastic, epithelial-lined cysts located in the sellar and suprasellar regions, which are known to be derived from the remnants of the Rathke pouch at 3–4 weeks' gestation.1, 2, 3 RCCs are diagnosed with histologic verification of a single layer of cuboidal or columnar epithelium, including cilia and goblet cells, which secret mucus into the cyst cavity.2, 4 RCCs are usually asymptomatic and can be found in 13%–22% of unselected autopsy studies.1, 2, 5 Inflammation spread by the cyst contents and the effects of the cyst compressing on the surrounding structures infrequently induce headaches, endocrinologic insufficiency, and visual function disturbance.6, 7, 8
Although calcification of the cyst wall in RCC is rare, ossification occurs even less frequently, as only four cases have been reported.4, 9, 10, 11 Because calcification is commonly found in craniopharyngioma, its presence plays an important role in distinguishing the 2 disorders.12, 13 Although, it is believed that calcification can arise from chronic inflammation of the wall, the detailed mechanism of ossification in RCC remains unknown. In this case, the developmental mechanism of an extremely rare case of ossified RCC was explored with an immunohistochemistry (IHC) study.
Section snippets
Case Description
A 60-year-old woman complaining of headaches, fatigue, and weight loss consulted the local hospital in May 2013. Computed tomography showed a round cyst in the sellar region and calcification on the cyst wall (Figure 1A). Magnetic resonance imaging (MRI) revealed an oval mass in the sellar region with suprasellar extension. The mass had two different parts of anterior hypointensity with heterogeneous contrast enhancement and of homogeneous posterior hyperintensity on T1-weighted imaging (
Discussion
Although ossification of the sellar lesion is usually found in craniopharyngioma, it is extremely rare in RCC and, to our knowledge, only 4 cases have been reported.4, 9, 10, 11 In craniopharyngioma, the ossification is presumed to be caused by metaplasia owing to chronic inflammation. Sato and Kubota13 proposed the mechanism of ossification based on a study using light and electron microscopy. They observed that keratinized cell masses in craniopharyngioma sometimes came into direct contact
Conclusion
Long-term of chronic inflammation induced by the RCC content could promote mature bone formation, an elastically solid nodule, and old and new phases of hemorrhage possibly from granulation tissue. This metaplastic ossification of the wall strongly suggested unusual, extreme, and complex process of persistent inflammation.
References (30)
- et al.
Clinicopathological analysis of primary lung carcinoma with heterotopic ossification
Lung Cancer
(2009) - et al.
Low-grade fibromyxoid sarcoma with prominent giant rosettes and heterotopic ossification
Pathol Res Pract
(2012) - et al.
Osseous metaplasia in ovarian papillary serous cystadenocarcinoma
Gynecol Oncol
(1990) - et al.
Extensive diffuse pulmonary ossification
Chest
(1992) - et al.
Surgical treatment of symptomatic Rathke cleft cysts: clinical features and results with special attention to recurrence
J Neurosurg
(2004) - et al.
Symptomatic Rathke's cleft cysts. Report of two cases
J Neurosurg
(1982) - et al.
Neoplasms of the sellar region
- et al.
A partially ossified solid and cystic Rathke cleft cyst
J Neurosurg
(2010) The incidence and distribution of cilia in the human pituitary with a distribution of micro-follicular cysts derived from Rathke's cleft
Acta Anat
(1951)- et al.
Rathke cleft cyst: MR and biomedical analysis of cyst content
J Comput Assist Tomogr
(1999)
Pure lymphocytic infundibuloneurohypophysitis caused by the rupture of rathke's cleft cyst: report of 2 cases and review of the literature
Turk Neurosurg
Computed tomography in intra- and suprasellar epithelial cysts (symptomatic Rathke cleft cysts)
AJNR Am J Neuroradiol
Atypical Rathke's cleft cyst associated with ossification
AJNR Am J Neuroradiol
Large ossified Rathke's cleft cyst—a case report and review of the literature
J Korean Neurosurg Soc
Ossified Rathke cleft cyst: a rare variant
Neurol India
Cited by (1)
Sellar Pathologies Mimicking Pituitary Tumors
2020, Neurology India
Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.