case_images: PMC10467173_01
case_images: A contrast-enhanced computed tomography (CT) scan in a 63-year-old man with protruding anal lesion diagnosed with melanoma of the rectum shows on coronal (a) axial (b) and sagittal (c) images a heterogeneous, irregular endophytic rectal tumor without extension into peri rectal fat (red arrow).
case_images: 10.1177_2050313X231194150-fig1.jpg
case_images: PMC10467173_01_10.1177_2050313X231194150-fig1.jpg
case_images: fig1-2050313X231194150
case_images: There was a mesorectal lymphadenopathy but no distant metastasis (Figure 1).
case_images: MRI of the pelvis of the same patient demonstrates an intermediate signal lobulated rectal mass on sagittal T2w images (a) (red arrow), T1 hyperintense (b), restrictive in diffusion sequences (c), and strongly enhancing in post-enhanced and subtracted images (e, f). This mass extends to anal sphincters but respects the peri-rectal fat. Mesorectal lymphadenopathy is also found (f) (white arrow).
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case_images: PMC10467173_01_10.1177_2050313X231194150-fig2.jpg
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case_images: T1 hyperintense, intermediate signal in T2W, restrictive in diffusion sequences, strongly enhancing after GADOLINIUM administration, extending to anal sphincters, respecting the mesorectum but spreading to a mesorectal node (Figure 2). These findings are conclusive of a stage 2 anorectal melanoma and T2N1M0.
case_images: Extemporaneous anatomopathological study of the mesorectal lymph node showed an infiltrated lymph node parenchyma by a melanoma of cordal and massive architecture, composed of epitheloid or spindle-shaped cells of large size endowed with oval nuclei with nucleolated heterogeneous chromatin.
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case_images: fig3-2050313X231194150
case_images: Squamous (anal) type mucosa. In the lamina propria, with tumoral proliferation of fusiform cells arranged in bundles and epitheloid cells arranged in thecae.
case_images: 10.1177_2050313X231194150-fig4.jpg
case_images: PMC10467173_01_10.1177_2050313X231194150-fig4.jpg
case_images: fig4-2050313X231194150