case_images: PMC10408634_01
case_images: Coronal (a) and axial (b) views of T1-weighted magnetic resonance imaging with gadolinium showing a well-defined expansive lesion, with homogeneous enhancement in the olfactory groove topography.
case_images: SNI-14-231-g001.jpg
case_images: PMC10408634_01_SNI-14-231-g001.jpg
case_images: F1
case_images: On complementary magnetic resonance imaging investigation, a 4.0 x 3.8 cm infiltrative extra-axial lesion was observed, with contrast uptake, located at the base of the skull in the olfactory groove topography associated with intense peritumoral edema and absence of other lesions [Figures 1 and 2].
case_images: Axial view (a and b) of Fluid-attenuated inversion recovery (FLAIR) showing intense peritumoral brain edema.
case_images: SNI-14-231-g002.jpg
case_images: PMC10408634_01_SNI-14-231-g002.jpg
case_images: F2
case_images: On complementary magnetic resonance imaging investigation, a 4.0 x 3.8 cm infiltrative extra-axial lesion was observed, with contrast uptake, located at the base of the skull in the olfactory groove topography associated with intense peritumoral edema and absence of other lesions [Figures 1 and 2].
case_images: (a) 100XX - Monophasic synovial sarcoma with fibrosarcoma-like areas, spindle-shaped cells with moderate nuclear pleomorphism arranged in long and intercalated fascicles. (b) 400 XX - Hyperchromatic, fusiform nuclei cells arranged in long bundles. (c) TLE-1 400XX - Strong and diffuse nuclear expression antibody in neoplasia. (d) CD99 400XX - Cytoplasmatic and diffuse membrane expression antibody.
case_images: SNI-14-231-g003.jpg
case_images: PMC10408634_01_SNI-14-231-g003.jpg
case_images: F3
case_images: After gross total resection, the pathological examination showed MSS in the olfactory groove [Figure 3].
case_images: First-day postoperative computed tomography scan showing gross total resection of the tumor.
case_images: SNI-14-231-g004.jpg
case_images: PMC10408634_01_SNI-14-231-g004.jpg
case_images: F4
case_images: Immunohistochemical analysis is shown in Table 2, and 1st-day postoperative computed tomography scan is shows aggressive gross total resection [Figure 4].
case_images: Fractionated stereotactic radiotherapy with intensity modulated radiation therapy and localization by image-guided radiotherapy. Total dose: 2.500 cGy in 5 fractions. Daily dose: 500 cGy.
case_images: SNI-14-231-g005.jpg
case_images: PMC10408634_01_SNI-14-231-g005.jpg
case_images: F5
case_images: The patient returned to the hospital with similar symptoms to the first diagnosis (5 months after the procedure), evaluations showed that the lesion had relapsed and hence was reoperated on, in which the MSS was again gross totally resected, and the patient was further referred for oncologic adjuvant treatment with fractionated stereotactic radiotherapy [Figure 5].