case_images: PMC9377515_01
case_images: Photograph of the right temporal mass (red arrows) seen the morning after the patient's first coronavirus disease 2019 vaccination (BNT162b1) (photograph taken by the patient's family member).
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case_images: PMC9377515_01_fmed-09-963393-g0001.jpg
case_images: F1
case_images: An 80-year-old Japanese woman with a medical history of hypertension, angina pectoris, mitral valve regurgitation, and ovarian tumor resection was referred for further examination of a right temporal mass (Figure 1) that suddenly appeared the morning after she received her first COVID-19 vaccine (BNT162b2) in her left deltoid muscle. The number of swollen submandibular and parotid glands had also increased from 14 glands at the last visit to >22 glands, and the maximum size of the pre-existing lymphadenopathies had enlarged from 7.5 to 13.3 mm (Figures 3E-G). 18F-fluorodeoxyglucose (FDG) positron emission tomography-CT demonstrated abnormal FDG uptake in the mass, right parotid glands, and lymphadenopathies (maximum standardized uptake value, 6.92) (Supplementary Figure 1).
case_images: Grayscale (A) and color Doppler (B) images of the right temporal mass showing a uniformly hypoechoic teardrop-shaped mass with well-defined margins (A) and decreased vascularity (B).
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case_images: PMC9377515_01_fmed-09-963393-g0002.jpg
case_images: F2
case_images: US revealed the size of the mass to be 28.5 x 5.7 mm (Figures 2A,B), and the palpable lymph nodes were <= 10.2 mm in diameter.
case_images: Axial computed tomography image obtained at the first visit shows 14 lymphadenopathies, with a maximum diameter <= 7.5 mm (red arrows) in the right parotid region (A), submandibular and jugular regions (B), and supraclavicular region (C). Measurement of the right temporal mass (68.3 x 17.1 mm) on an axial contrast-enhanced computed tomography image 9 weeks after the first visit to our institution (D). The lymphadenopathies (maximum size <= 13.3 mm, yellow arrows) in the right parotid region (E), submandibular and jugular region (F), and supraclavicular region (G).
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case_images: PMC9377515_01_fmed-09-963393-g0003.jpg
case_images: F3
case_images: CT of the neck, thorax, abdomen, and pelvis revealed 14 lymphadenopathies in the right parotid, submandibular, jugular, and supraclavicular regions, all of which were <= 7.5 mm (Figures 3A-C). The size of the right temporal mass had increased from 28.5 x 5.7 mm to 68.3 x 17.1 mm in 10 weeks (from weeks 6 week 16 after the first vaccination) (Figure 3D). The number of swollen submandibular and parotid glands had also increased from 14 glands at the last visit to >22 glands, and the maximum size of the pre-existing lymphadenopathies had enlarged from 7.5 to 13.3 mm (Figures 3E-G). 18F-fluorodeoxyglucose (FDG) positron emission tomography-CT demonstrated abnormal FDG uptake in the mass, right parotid glands, and lymphadenopathies (maximum standardized uptake value, 6.92) (Supplementary Figure 1).
case_images: Hematoxylin and eosin staining of the biopsy specimen showing diffuse proliferation of small- to medium-sized lymphoid cells with slightly enlarged round nuclei (magnification, x 200) (A). Immunohistochemical staining showing lymphoid cells positive for CD20 (x 100) (B) and bcl-2 (x 100) (C) and negative for CD5 (x 100) (D), CD10 (x 100) (E), and cyclin D (x 100) (F).
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case_images: PMC9377515_01_fmed-09-963393-g0004.jpg
case_images: F4
case_images: Pathological examination showed diffuse proliferation of small- to medium-sized lymphoid cells with slightly enlarged round nuclei (Figure 4A).