case_images: PMC10830151_01
case_images: Ultrasound of the bladder: post-micturition, longitudinal view. An 18-mm mass was noted at the anterior bladder wall.
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case_images: FIG1
case_images: He was referred for an ultrasound of the urinary tract, which demonstrated a 14 x 15 x 18mm lesion on the right anterior bladder wall, associated with gross thickening of the bladder wall, and an elevated postvoid residual of 106 cm with no hydroureter or hydronephrosis (Figure 1).
case_images: Multiparametric magnetic resonance imaging of the prostate: 30mm PI-RADS 5 lesion with characteristic T2 hypointensity involving the right peripheral zone and transition zone from base to apex.
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case_images: PMC10830151_01_cureus-0016-00000051481-i02.jpg
case_images: FIG2
case_images: Multiparametric magnetic resonance imaging of the prostate found a non-enlarged prostate measuring 23.4cc and a 30mm PI-RADS 5 (prostate imaging reporting and data system) lesion, extending from base to apex across the right peripheral zone and transition zone, with no overt extraprostatic extension or seminal vesicle invasion (Figure 2).
case_images: Histopathology and immunoperoxidase stain (IHC) of small cell carcinoma of the bladder in this patient. (A) Hematoxylin and eosin. Sheets to nests of high-grade tumor cells with neuroendocrine differentiation invading muscle. (B) CD56 IHC-positive. (C) Synaptophysin IHC is positive. (D) GATA3 IHC is negative.
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case_images: FIG3
case_images: The small cell component showed archetypal immunoperoxidase staining for neuroendocrine differentiation, with strong expression of neuroendocrine markers CD56 and synaptophysin and a lack of expression of GATA3, a marker for urothelial differentiation (Figures 3A-3D).
case_images: Histopathology and immunoperoxidase stain (IHC) of high-grade papillary urothelial carcinoma of the bladder in this patient. (A) Hematoxylin and eosin. Malignant cells with classic "mosaic tile" urothelial differentiation, organized around a fibrovascular core. (B) CD56 IHC is negative. (C) Synaptophysin IHC is negative. (D) GATA3 IHC positive.
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case_images: FIG4
case_images: The muscle-invasive high grade papillary urothelial carcinoma lacked expression of both neuroendocrine markers and expressed GATA3 strongly (Figures 4A-4D).
case_images: Histopathology of prostate core biopsies, hematoxylin, and eosin: a mix of pattern 5 and 4 prostate acinar adenocarcinomas, with no neuroendocrine differentiation.
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case_images: FIG5
case_images: One month later, a transrectal ultrasound-guided core biopsy of the prostate demonstrated high-grade acinar adenocarcinoma, Gleason 5+4=9 in 11 out of 13 cores, ISUP (International Society of Urological Pathology) Grade Group 5, with perineural invasion and intraductal carcinoma, but no evidence of neuroendocrine differentiation (Figure 5).
case_images: Staging positron emission tomography (PET) scans. (A) Fludeoxyglucose-PET uptake in the prostate primary, SUV max 6. (B) Fludeoxyglucose-PET uptake in a right external iliac lymph node, SUV max 4.2, PET, and co-registered computer tomography scans presented side by side. (C) Gallium-68 prostate-specific membrane antigen-PET uptake in the prostate primary, SUV max 27.
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case_images: FIG6
case_images: Staging fludeoxyglucose positron emission tomography (FDG-PET) showed intense right-sided prostatic uptake from base to apex, SUV max 6.0 (Figure 6A). Prostate-specific membrane antigen positron emission tomography (PSMA-PET) also showed intense right-sided prostatic uptake from base to apex, SUV max 27.0 (Figure 6C). A right external iliac lymph node was moderately FDG-PET avid, SUV max 4.2 (Figure 6B), but demonstrated minimal PSMA-PET avidity (SUV max 1.8).
case_images: Prostate magnetic resonance imaging is used for radiotherapy planning. A hyperintense T2 signal is seen in the spaceOAR barrier gel inserted between the rectum and prostate. (A) Axial view. (B) Sagittal view.
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case_images: FIG7
case_images: He underwent prostate fiducial seed and barrier gel placement and an MRI prostate for radiotherapy planning (Figures 7A-7B).
case_images: Dose distribution and target volumes of the treatment plan employing Volumetric Modulated Arc Therapy. Pink line: High risk planning target volume. Yellow line: Low risk planning target volume. Green line: Bladder. Red line: Prostate. Isodoses are presented in dose-wash. (A) Axial slice at the level of the prostate. Absolute dose (Gy) of isodose lines is displayed on the left. (B) Coronal slice. (C) Sagittal slice.
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case_images: FIG8
case_images: Dose distribution and target volume contours are represented in Figures 8A-8C.