ABSTRACT
Iodinated contrast media can rarely cause severe allergic reactions during nonvascular urologic imaging procedures. Alternatives like gadolinium-based contrast may help mitigate this risk in susceptible patients. A 66-year-old woman with a documented iodine allergy presented with an obstructing stone in the right ureter. To avoid the risk of an allergic reaction, the decision was made to use an alternative non-iodinated contrast agent for retrograde pyelography prior to ureteral stent placement. Gadobenate dimeglumine, an MRI contrast agent, was diluted 50:50 with saline and utilized successfully to provide adequate opacification for safe stent placement without adverse reaction. The patient underwent repeat pyelography with gadobenate dimeglumine one month later during ureteroscopy without complication. This case demonstrates that diluted gadobenate can serve as an effective alternative to iodinated contrast media in patients at high risk of reaction to iodine-containing agents. While severe reactions to iodinated contrast are uncommon in nonvascular urologic procedures, they can still occur even with premedication. Gadolinium-based agents have been reported to provide sufficient opacification for most urologic interventions, though inferior radiographically to iodinated contrast. Further study on gadolinium efficacy and safety in this setting is warranted. However the present case supports gadobenate dimeglumine as a viable option for retrograde pyelography when allergy risk precludes iodinated contrast use.
ABSTRACT
Prostate cancer (PCa) identified incidentally (iPCa) after surgical treatment for symptomatic benign prostatic hyperplasia (BPH) causing lower urinary tract symptoms (LUTS) is considered low risk by the most current guidelines. Management protocols for iPCa are conservative and are identical to other prostate cancers classified as having favorable prognoses. The objectives of this paper are to discuss the incidence of iPCa stratified by BPH procedure, to highlight predictors of cancer progression, and to propose potential modifications to mainstream guidelines for the optimal management of iPCa. The correlation between the rate of iPCa detection and the method of BPH surgery is not clearly defined. Old age, small prostate volume, and high pre-operative prostate-specific antigen (PSA) are associated with an increased likelihood of detecting iPCa. PSA and tumor grade are strong predictors of cancer progression and can be used along with magnetic resonance imaging (MRI) and potential confirmatory biopsies to determine disease management. In instances that iPCa requires treatment, radical prostatectomy (RP), radiation therapy, and androgen deprivation therapy all have oncologic benefits but may be associated with increased risk after the BPH surgery. It is advised that patients with low to favorable intermediate-risk prostate cancer undergo post-operative PSA measurement and prostate MRI imaging before electing to choose between observation, surveillance without confirmatory biopsy, immediate confirmatory biopsy, or active treatment. Subdividing the binary T1a/b cancer staging into more categories with ranging percentages of malignant tissue would be a helpful first step in tailoring the management of iPCa.
