Central abdominal uptake of indium-111 capromab pendetide (ProstaScint) predicts for poor prognosis in patients with prostate cancer

Diagnostic performance of In-111 capromab pendetide SPECT/CT in localized and metastatic prostate cancer

PURPOSE

To determine the diagnostic performance of In-111 capromab pendetide single photon emission computed tomography/computed tomography (SPECT/CT), in the prostate gland, seminal vesicles, and lymph nodes via correlation to a gold standard of histopathology.

MATERIALS AND METHODS

In this study, we retrospectively reviewed all In-111 capromab pendetide SPECT/CT acquired at our institution for dedicated histopathology within a 4-month period. Statistical measures of performance were calculated in terms of glandular, seminal vesicle, and lymph node activity. The accuracies of glandular and seminal vesicle activity were then correlated to the indices of risk, including the stage, Gleason score, and prostate-specific antigen level, as well as the treatment history.

RESULTS

Of the 200 scans meeting the criteria of our study, 197 had prostate gland histopathology, 94 had bilateral seminal vesicle histopathology, and 5 had a total of 43 resected lymph nodes for comparison. The overall accuracies of the scan results were determined to be 77.7% (area under the receiver operating characteristic curve [AUC] = 0.539) for the gland, 67.0% (AUC = 0.510) for the seminal vesicles, and 93.0% (AUC = 0.787) for lymph nodes. For glandular activity alone, scan accuracy was found to significantly improve with increasing Gleason score (P < 0.0001), and in a setting prior to treatment (P = 0.0005). No statistically significant differences were found between different scan groups with regards to seminal vesicle activity.

CONCLUSIONS

The results of this study provide substantiating evidence In-111 capromab pendetide can be used to accurately diagnose lymph node metastases from primary cancers of the prostate; however, they also suggest the test may have limited utility in diagnosing tumors within the prostate gland and seminal vesicles.

A review on the clinical uses of SPECT/CT

In the era when positron emission tomography (PET) seems to constitute the most advanced application of nuclear medicine imaging, still the conventional procedure of single photon emission computed tomography (SPECT) is far from being obsolete, especially if combined with computed tomography (CT). In fact, this dual modality imaging technique (SPECT/CT) lends itself to a wide variety of useful diagnostic applications whose clinical impact is in most instances already well established, while the evidence is growing for newer applications. The increasing availability of new hybrid SPECT/CT devices with advanced technology offers the opportunity to shorten acquisition time and to provide accurate attenuation correction and fusion imaging. In this review we analyse and discuss the capabilities of SPECT/CT for improving sensitivity and specificity in the imaging of both oncological and non-oncological diseases. The main advantages of SPECT/CT are represented by better attenuation correction, increased specificity, and accurate depiction of the localization of disease and of possible involvement of adjacent tissues. Endocrine and neuroendocrine tumours are accurately localized and characterized by SPECT/CT, as also are solitary pulmonary nodules and lung cancers, brain tumours, lymphoma, prostate cancer, malignant and benign bone lesions, and infection. Furthermore, hybrid SPECT/CT imaging is especially suited to support the increasing applications of minimally invasive surgery, as well as to precisely define the diagnostic and prognostic profile of cardiovascular patients. Finally, the applications of SPECT/CT to other clinical disorders or malignant tumours is currently under extensive investigation, with encouraging results in terms of diagnostic accuracy.

Tumor biology-guided radiotherapy treatment planning: gross tumor volume versus functional tumor volume

This issue of Seminars in Nuclear Medicine deals with a watershed event in cancer treatment -- the combined use of functional and anatomical information to guide therapeutic interventions. The use of positron emission tomography/computed tomography (PET/CT) in radiation treatment planning and tumor response evaluation brings a paradigm change in the development of image-guided therapies into routine clinical practice. The implications, as seen in the following articles, are not only promising but also groundbreaking. And, as in every new scientific breakthrough, each step forward generates a myriad of additional important clinical and research questions. Functional imaging takes advantage of the subtle differences between normal and malignant tissues at the cellular level to reveal in vivo unique functional characteristics of neoplasms. The ultimate goal of the partnership between nuclear medicine physicians and radiation oncologists is to use this information with absolute clarity in target definition for radiation treatment planning and therapy, as well as response evaluation. Functional imaging can provide metabolic information and behavioral correlation along with the anatomical imaging for correlative target delineation. Additionally, as a purely diagnostic instrument, PET/CT provides a tool for oncologists to make critical decisions regarding radiation treatment planning modifications secondary to changes in tumor staging (up or down), treatment field modifications, localized control, sites of residual and/or metastatic disease and post therapy response evaluation. The articles in this issue of the seminars provide insights into the current state-of-the-art of functional imaging techniques, mostly centered on the use of (18)F-fluorodeoxyglucose PET/CT in image guided oncologic therapies. Because it is a novel science, the future of image-guided functional treatment planning is bright with technologic and biologic innovations, translational research and new clinical applications.

Indium-111 capromab pendetide in the management of recurrent prostate cancer

The provision of accurate prognostic information is a long-standing goal for effective management of prostate adenocarcinoma. Nontargeted imaging modalities are less efficient at detecting slow-growing prostate cancers. Prostate-specific membrane antigen has emerged as a superior biomarker, especially for the evaluation of metastatic spread. Advances in imaging technology have focused clinical interest on indium-111 capromab ((111)In capromab) pendetide, a radioimmunoconjugate that detects prostate-specific membrane antigen expression in vivo. Single-photon emission computed tomography capromab pendetide images, fused with those generated by computed tomography or magnetic resonance, have engendered improvements in localization accuracy by correlating high signal intensity with anatomic structures. In long-term outcomes studies, fused (111)In capromab pendetide scans have delivered significant benefits for patient selection and improved treatment of prostate cancer.