Clin Endosc.  2021 Nov;54(6):939-941. 10.5946/ce.2021.243.

Hematochezia in Patient with Rectal Tumor: Consideration of Various Diagnostic Possibilities

• Jeong HM
• Bang CS
• Baik GH

• KMID: 2522720
• DOI: http://doi.org/10.5946/ce.2021.243

Figure

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  Fig. 1. (A, B) Colonoscopy demonstrating 3 cm mass covered with exudates near anal canal. (C) Endoscopic ultrasonography demonstrating heterogenous hypoechoic lesion in the submucosal layer.

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  Fig. 2. Histopathological findings of the biopsy specimens. Small malignant oval-shaped cells with high nuclear-to-cytoplasmic ratio with poor differentiation (normal glandular structure was not observed) (hematoxylin and eosin stain ×200).

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  Fig. 3. (A, B) Contrast-enhanced computed tomography demonstrating 3.5 cm enhancing lesion involving distal rectum and anorectal junction.

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  Fig. 4. (A, B) Positron emission tomography demonstrating 3-3.5 cm mass with increased FDG uptake (SUVmax=10.79) in the distal rectum.

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  Fig. 5. Surgical specimen demonstrates an ill demarcated ulcerative and fungating mass, measuring 3.3×2.7 cm extending to the pericolic soft tissue.

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  Fig. 6. Histopathological findings of the surgically resected specimen. (A, B) Round cells with a high nuclear-to-cytoplasmic ratio without macronucleoli which invaded whole mucosal layer (hematoxylin and eosin stain ×100). (C) Diffuse brown colored pigmentation (hematoxylin and eosin stain ×200)

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  Fig. 7. Immunohistochemistry findings of the surgically resected specimen. (A, B) The tumor cells are diffusely positive for HMB-45 and S-100 (hematoxylin and eosin stain ×100).

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