Single photon emission computerized tomography with capromab pendetide plus computerized tomography image set...

Area of Science:

• Oncology
• Radiotherapy
• Nuclear Medicine Imaging

Background:

• Accurate staging is crucial for localized prostate cancer treatment planning.
• Detecting occult metastatic disease can refine treatment strategies and predict outcomes.

Purpose of the Study:

• To assess the utility of pretreatment (111)Indium capromab pendetide (ProstaScint) immunoscintigraphy combined with SPECT/CT.
• To determine if this imaging modality can detect occult metastases and predict biochemical failure in prostate cancer patients undergoing radiotherapy.

Main Methods:

• A cohort of patients with localized prostate cancer referred for primary radiotherapy were evaluated.
• Pretreatment SPECT/CT scans were analyzed for metastatic disease, seminal vesicle extension, and organ-confined disease.
• Patients were followed for biochemical failure using prostate-specific antigen (PSA) nadir +2 ng/ml and ASTRO definitions.

Main Results:

• Biochemical failure rates were significantly higher in patients with extra-periprostatic metastatic disease detected on SPECT/CT (43.2%) compared to those with seminal vesicle extension (16.0%) or organ-confined disease (14.7%).
• Cox regression analysis revealed that extra-periprostatic metastases on SPECT/CT independently predicted a 4.2- to 4.5-fold increased risk of biochemical failure.
• SPECT/CT findings of seminal vesicle extension also predicted an increased risk of failure.

Conclusions:

• Pretreatment SPECT/CT immunoscintigraphy is a valuable tool for detecting occult metastatic prostate cancer.
• Findings of extra-periprostatic disease on SPECT/CT independently predict an increased risk of biochemical failure in patients with localized prostate cancer undergoing radiotherapy.