Screening Agent Helps Detect Prostate Cancer Recurrence Earlier
A study conducted by researchers at Duke University and Johns Hopkins Medical Centers and published in the journal Cancer (94:987-996) found that the use of indium-111-capromab pendetide (ProstaScint), a radiolabeled monoclonal antibody imaging agent, allowed identification of recurrent prostate cancer earlier than conventional imaging methods, such as the computed tomography (CT) scan. Prostate cancer recurs in nearly 40% of patients, and about 11% are at high risk for metastatic spread of the disease. Conventional imaging methods are often only able to detect a more advanced stage of prostate cancer.
A study conducted by researchers atDuke University and Johns Hopkins Medical Centers and published in the journal Cancer (94:987-996) found that the use of indium-111-capromab pendetide(ProstaScint), a radiolabeled monoclonal antibody imaging agent, allowedidentification of recurrent prostate cancer earlier than conventional imagingmethods, such as the computed tomography (CT) scan. Prostate cancer recurs innearly 40% of patients, and about 11% are at high risk for metastatic spread ofthe disease. Conventional imaging methods are often only able to detect a moreadvanced stage of prostate cancer.
These findings could have a significant effect on treatment.For example, patients whose cancer is localized might be able to avoidundergoing a full course of chemotherapy. If the cancer has metastasized, somepatients could avoid unnecessary surgery or radiation therapy as well as theside effects that often accompany these treatments, such as incontinence anderectile dysfunction.
Study Protocol
The multicenter study led by Ganesh V. Raj, MD, PhD, from theDivision of Urology, Duke University Medical Center, involved 255 men, who,after undergoing a radical prostatectomy, received no additional therapy andsubsequently had an increase in their prostate-specific antigen (PSA) levels asthe only indication that their cancer had recurred. These patients, whose PSAlevels ranged from 0.1 to 4.0 ng/mL, then underwent capromab pendetideimmunoscintigraphy to localize their disease.
The scan identified recurrent disease in 72% of patients witha PSA ≤ 4.0 ng/mL. Of 151 patients who underwent additional studies, boneand/or CT scans identified recurrence in 12% (16/139) and 16% (15/92) ofpatients, respectively.
"In most instances, conventional imaging modalities such as a CT scandetect a recurrence of prostate cancer only when a volume of cancer effectschanges to normal anatomic structures, which also indicates a significantadvance in disease progression," said Dr. Raj. "This study suggeststhat a ProstaScint scan may detect and localize recurrent prostate cancerearlier than previously thought possible for patients with a low serum PSA afterradical prostatectomy."
