Cooking Up the Truth: Heat-Damaged RBC Imaging in a Case of Suspected Lymphoma

Area of Science:

• Urology
• Nuclear Medicine
• Pathology

Background:

• Elevated prostate-specific antigen (PSA) levels can indicate prostate cancer but may also be associated with other conditions.
• Pelvic masses require thorough investigation to differentiate between malignant and benign etiologies.
• Splenosis, the ectopic splenic tissue, can mimic other pathologies, particularly in the abdomen and pelvis.

Purpose of the Study:

• To present a case of pelvic splenosis initially misdiagnosed as lymphoma based on imaging and biopsy.
• To highlight the diagnostic challenges in differentiating pelvic splenosis from other pelvic masses.
• To emphasize the importance of comprehensive pathological review in establishing an accurate diagnosis.

Main Methods:

• Prostate Magnetic Resonance Imaging (MRI) to evaluate the pelvic mass.
• Biopsy for initial pathological assessment.
• Fluorine-18 fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (¹⁸F-FDG PET/CT) for staging and assessing metabolic activity.
• Heat-damaged red blood cell scintigraphy to confirm splenic tissue.
• Review of outside pathology to re-evaluate initial findings.

Main Results:

• Prostate MRI revealed a mass between the prostate and rectum.
• Initial biopsy suggested low-grade B-cell lymphoma.
• ¹⁸F-FDG PET/CT showed a mildly avid pelvic mass and abdominal splenosis.
• Heat-damaged red blood cell scintigraphy confirmed pelvic splenosis.
• Re-evaluation of pathology ruled out lymphoma, confirming splenosis.

Conclusions:

• Pelvic splenosis can present as a pelvic mass mimicking malignancy, such as lymphoma.
• Integrated diagnostic approaches combining MRI, PET/CT, scintigraphy, and meticulous pathology review are crucial.
• Accurate diagnosis of pelvic splenosis prevents unnecessary treatment for misdiagnosed conditions like lymphoma.