A Potential Concomitant Sellar Embryonic Remnant-Associated Collision Tumor: Systematic Review

Abstract

Background: Diagnosing the well-known concomitant Rathke's cleft cyst (RCC) and differentiating it from other sellar lesions are difficult because RCC is and other sellar lesions are closely related and represent a continuum from simple RCCs to more complex lesions. The purpose of this study is to better understand the adeno- and neurohypophysis adjacent to the par intermedia remnants and their role in the origin of the coexistence of these two distinct tumor neoplasias; to assess the incidence in different age groups; to categorize the pathohistological subtype, which can be incorporated in predictive/prognostic models; and finally, to evaluate the current evidence on collision tumors of the sellar embryonic remnant tract in terms of their biological behavior and pathology.

Methods: Utilizing the PubMed database, data were collected from 1920 to 2019. Information about demographics, clinical characteristics, and age was summarized and analyzed by using univariable and multivariable models. The same cell type was observed regardless of whether the tumor was only one type or mixed types, and their histologic patterns were assessed.

Results: The incidence rates were similar among patients stratified into three age subgroups: 40-49 years (24.57%), 50-59 years (19.54%), and older than 60 years (22.98%). We found that various types of sellar lesions, namely, squamous metaplasia (SM) + goblet cells (GC) (HR 46.326), foamy macrophages (FM) (HR 39.625), epithelial cells and multinucleated giant cells or cholesterin (EM) (HR 13.195), a cavernous portion of the right internal carotid artery (CP-ICA) (HR 9.427), epithelial cells with ciliated cuboidal (EC-CC) (HR 8.456), were independently associated with RCC pathological status. These divergent AUCs (0.848 for Hypo as RCC, 0.981 for RCC co PA, 0.926 for CD and CP co RCC) and subtypes of PA (HR 4.415, HR 2.286), Hypo (HR 3.310), CD and CP (HR 2.467), EC and DC and PG and SGR (HR 1.068), coexisting with the risk of a comorbid RCC lesion, may reflect the etiologic heterogeneity of coderivation and the different effects of some risk factors on tumor subtypes. Our analyses suggested that the greatest accuracy was observed for the pituitary adenoma subtype, with an AUC of 0.981 (95% confidence interval [CI]: 0.959-1.005), while the poorest accuracy was observed for aneurysms, with an AUC of 0.531 (95% CI: 0.104-0.958). We separately analyzed and confirmed the above results. Sensitivity analysis revealed no evidence of systematic bias due to missing data.

Conclusion: This study showed that the histopathological changes in patients with sellar embryonic remnant-associated collision tumors showed highly consistent epithelial cell replacement (renewal) (ciliated columnar epithelium to ciliated squamous epithelium to squamous epithelium) or accumulation, and the RCC cyst wall was similar in structure to the tracheobronchial airway epithelium, with progenitor cell characteristics. The collision accuracy between RCC and other tumors (PAs, craniopharyngioma, chordoma, etc.) is different; these characteristics constitute the theoretical basis for the postmigration development of the pharyngeal bursa.

Keywords: Rathke cleft cyst; collision sellar lesions; cystic sellar lesions; sellar embryonic-remnants lesions; solid sellar lesion.

Figure 1

Forest plot for the subgroup analysis of various population-based age groups and risk of age graph. This graph compares the risk of various subgroups (represented by combined RCC with sellar lesion) in each age group and the degree of merger risk within the age group (30–39 y, 50–59 y) calculated using our predictive model.

Figure 2

AUC determination using receiver operating characteristic (ROC) curves. (A) Information on the results of age group value markers and RCC coexisting with pituitary adenoma subtype, assessed by the AUC. (B) Information on the age group value markers and RCC coexisting with hypophysitis, assessed by the AUC. (C) Information on the age group value markers and RCC coexisting with aneurysm, assessed by the AUC. (D) Information on the age group value markers and RCC coexisting with other sellar lesions, assessed by the AUC. (E) RCC and various sellar lesions in 118 patients classified into five groups according to different sellar lesions. Total ROC plot.

Figure 3

Kaplan-Meier plot for overall survival (OS) (A) and relapse-free survival (RFS) (B) in patients with RCC coexisting with various sellar lesions. (A, 1): Kaplan-Meier plot for overall survival in patients. The solid blue line represents patients with the coexistence of RCC and PA (n = 67). The solid green line represents patients with the coexistence of RCC and somatotroph adenoma (acromegaly) (n = 20). The solid yellow line represents patient with the coexistence of RCC and hypophysitis (n = 16). The solid purple line represents patients with the coexistence of RCC and aneurysm (n = 4). The solid yellow line represents patients with the coexistence of RCC and chordoma and craniopharyngioma (n = 5). The solid red line represents patients with the coexistence of RCC and other sellar lesions (n = 6) (epidermoid cyst, dermoid cyst, pituitary granulomatosis, salivary tumor, salivary gland remnants). There was no significant difference in OS and RFS between the six subgroups of patients (P = 0.231). (B, 2): Kaplan-Meier plot showing the relapse-free survival (RFS) of patients. There was no significant difference in OS and RFS among the six subgroups of patients (P = 0.664). The P-values were obtained by the log-rank (Mantel-Haenszel) test.

Figure 4

Review author's judgements about each risk of bias item for each included case series /case-control.

Figure 5

Histological feature of Aneurysm with Rathke’s cleft cyst, H&E stained section. (A) Shows the histological features of simple partial covered squamous epithelium with fibrous connective tissue presents acute and chronic inflammation (×150). (B) Squamous epithelial mucosa (×300). (C) The keratin in the cyst wall. (D) cystic wall lined by a squamous epithelium (×400). (E) Groups of inflammation cells (400×). (F) cuboidal ciliated epithelium cells(arrows) (×400).

Figure 6

Histological features of Human bronchial epithelium and Rathke’s cleft cyst epithelium, H&E stained section. (A) Ciliated bronchial epithelium (arrows) (×100). (B) Cuboidal ciliated epithelium (arrows) (×400).