An Adult Case of Sellar Atypical Teratoid/Rhabdoid Tumor Presenting with Lung Metastasis, Harboring a Compound Heterozygous Mutation in INI1

Abstract

A typical teratoid/rhabdoid tumors (AT/RT) are highly malignant embryonal tumors in children that are associated with inactivation of the integrase interactor 1 (INI1) gene. Several adult cases of AT/RT have been reported, which were characterized by the sellar occurrence and predominantly occurred in females with INI1 mutation variants. However, clinical and genetic features are poorly understood in this unusual entity. We experienced a case of a 45-year-old female with sellar AT/RT presenting diplopia, who underwent subtotal removal of the tumor by the endoscopic endonasal transsphenoidal approach. Pathological diagnosis was AT/RT with INI1 inactivation on immunohistochemistry. Subsequently, multiple lung metastases were confirmed on fluorodeoxyglucose positron emission tomography (FDG-PET). Although she received postoperative chemoradiotherapy, she died of cerebrospinal fluid dissemination. Autopsy revealed cerebrospinal dissemination and lung metastasis of AT/RT. Biallelic alterations in the INI1 gene were identified by direct sequencing, harboring on different alleles (compound heterozygous mutations) was observed, which is the potential genetic pattern in adult AT/RT. Literature review indicated that lung metastasis frequently occurs in sellar AT/RTs, which is accompanied by cavernous sinus invasion. These observations suggested that cavernous sinus invasion causes haematogenous metastasis to the lung in sellar AT/RT. We discuss clinical and pathological features in adult sellar AT/RT to improve understanding of this unique entity.

Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET)/Computed Tomography Features of Atypical Teratoid/Rhabdoid Tumors: Case Series and Review

“…As for the M staging, it is essential to conduct PET/CT examination to better evaluate the tumor progression. Similar to the reported adult case of sellar atypical teratoid/rhabdoid tumor with lung metastasis, 26 we also found metastases outside the central nervous system such as to the lung on PET/CT scan.…”

FDG PET/CT Findings of Malignant Rhabdoid Tumor Arising From a Renal Allograft

“…The presence of subcapsular fluid collection, multilobulated architecture, and calcifications may suggest a malignant rhabdoid tumor of the kidney 5–9 . A limited number of case reports demonstrate that malignant rhabdoid tumor may show intense 10–14 or low-grade 15–18 FDG uptake. FDG PET/CT findings of renal malignant rhabdoid tumor have been rarely reported 12 .…”