case_images: PMC5346921_01
case_images: Computed tomography scan of the abdomen/pelvis showing cecal mass (a) and enlarged prostate (b). The scan shows a prostatic space-occupying lesion with unclear rectal boundaries and an absence of the bladder seminal vesicle angle.
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case_images: A computerized tomography scan of the neck, chest, abdomen, and pelvis revealed diffuse urinary bladder wall thickening and an enlarged prostate, as well as a 2.4-cm soft tissue mass within the cecum involving the ileocecal valve, and no evidence of obstruction (Fig. 1).
case_images: Positron emission tomography scan showing increased uptake in the prostate prior to therapy (a) and decreased metabolic activity following treatment (b) and 12 months after therapy (c).
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case_images: A positron emission tomography (PET) scan showed significantly increased metabolic activity in the cecum and prostate gland (Fig. 2a) and mild 18F-fluorodeoxyglucose avidity within the distal esophagus. Posttreatment PET scans (Fig. 2b, c) showed complete remission, and the patient has been disease free for the past 2 years with continuing surveillance in our clinic.
case_images: A The prostate transurethral resection specimen was remarkable for a diffuse infiltrate of large atypical lymphoid cells and background small mature lymphocytes (a). The large atypical cells consisted of a mixture of immunoblast-like and centroblast-like cells that replaced the normal prostate parenchyma (b). (Hematoxylin and eosin at 200x magnification.) B Immunohistochemical staining of the large atypical lymphoid cells showed diffuse positivity with CD20 (a) and BCL-6 (b). Overall, the immunohistochemical staining patterns were consistent with a diagnosis of diffuse large B-cell lymphoma. (Both images at 200x magnification.)
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case_images: The large atypical cells were pleomorphic with irregular nuclear contours and occasional cleaved nuclei, and prominent nucleoli were also identified (Fig. 3A). The atypical cells expressed CD20, BCL-6 (Fig. 3B), and BCL-2 (variable positivity), while lacking expression of CD5, CD10, AE1/3, EMA, P501S, and PAP. The Ki-67 proliferation index accounted for approximately 30-40% of the atypical lymphocyte population. The overall morphology and immunohistochemistry profile was noted to be diagnostic of diffuse large B-cell lymphoma (DLBCL) (Fig. 3).