case_images: PMC10219605_01
case_images: Oral examination under anesthesia. (A) Oral examination under anesthesia revealed a ring-thickened mass on the left soft palate (blue arrow) before treatment. (B) Follow-up 4 months, the soft palate mass (blue arrow) was significantly reduced on oral examination after anesthesia.
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case_images: F1
case_images: The oral examination revealed a ring-thickened mass on the left soft palate (Figure 1A). Four months after the diagnosis, before the eighth dose, the gross appearance of the tumor was significantly reduced (Figure 1B).
case_images: Transverse computed tomography (CT) images. (A, B) CT images acquired before treatment, revealing the irregular mass from pharynx (blue arrow) and the enlarged medial retropharyngeal lymph node, 3.88 x 3.01 x 3.12 cm in size (red arrow). (C, D) Images from follow-up 4 months CT examination revealing the mass and LN both reached partial remission.
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case_images: F2
case_images: And CT scan further disclosed this pharyngeal mass as irregular in shape, 6.93 x 3.63 x 2.94 cm in size, characterized by ring and heterogeneous contrast enhancement with slight enhancement in the inner band and significant enhancement in the outer band, involving soft palate, epiglottis, left tonsil, part of the cricoid cartilage and adjacent muscles such as left medial pterygoid muscle, left digastric muscle and initiation of the longus capitis muscle (Figure 2A). In addition, the left medial retropharyngeal LN was irregularly enlarged with necrosis (3.88 x 3.01 x 3.12 cm; Figure 2B). Follow-up CT re-examination demonstrated that the pharyngeal mass had almost disappeared and the left medial retropharyngeal LN was only slightly enlarged (Figures 2C, D), with no evidence of distant metastasis.
case_images: Histopathological examination of the mass. Neoplastic mass consisted of long, dense, irregularly interlaced bundles of spindle cells, and a few of them formed irregular alveoli. Hematoxylin and eosin stain. (A) x100. (B) x400.
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case_images: PMC10219605_01_fvets-10-1144869-g0003.jpg
case_images: F3
case_images: Sections (5 mum) were cut and stained with hematoxylin and eosin (Figure 3).
case_images: Immunohistochemical (IHC) staining for cytokeratin (A), PD-L1 (B), vimentin (C), and melan-A (D), respectively, the Horseradish Peroxidase (HRP) method, neoplastic cells formed the glandular appearance and were intensely positive on cytokeratin and PD-L1, and negative on vimentin and melan-A. The surrounding connective tissue cells were positive on vimentin x400.
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case_images: F4
case_images: Neoplastic cells were intensely positive on cytokeratin IHC, and they were mostly negative on vimentin and melan-A IHC (Figure 4). III oral adenocarcinoma. In order to better indicate the treatment of anti-PD-1, PD-L1 IHC (Anti-PD-L1 Recombinant Rabbit Monoclonal Antibody; Huabio, Hangzhou, China) was performed on tumor cells, and the results were cytoplasmic positive (Figure 4B).