Learning Objectives: On successful completion of this activity, participants should be able to describe (1) the advantages and disadvantages of PET/MRI in oncologic applications in comparison to conventional imaging methods and PET/CT; (2) the limitations of PET/MRI compared with invasive staging procedures (biopsy); and (3) the metabolic-anatomic imaging procedure of choice (PET/MRI vs. PET/CT) based on tumor entity and location.Financial Disclosure: The authors of this article have indicated no relevant relationships that could be perceived as a real or apparent conflict of interest. CME Credit: SNM is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to sponsor continuing education for physicians. SNM designates each JNM continuing education article for a maximum of 1.0 AMA PRA Category 1 Credit. Physicians should claim only credit commensurate with the extent of their participation in the activity.For CE credit, participants can access this activity through the SNM Web site (http://www.snm.org/ce_online) through June 2013.In oncology, staging forms the basis for prognostic consideration and directly influences patient care by determining the therapeutic approach. Cross-sectional imaging techniques, especially when combined with PET information, play an important role in cancer staging. With the recent introduction of integrated whole-body PET/MRI into clinical practice, a novel metabolic-anatomic imaging technique is now available. PET/ MRI seems to be highly accurate in T-staging of tumor entities for which MRI has traditionally been favored, such as squamous cell carcinomas of the head and neck. By adding functional MRI to PET, PET/MRI may further improve diagnostic accuracy in the differentiation of scar tissue from recurrence of tumors such as rectal cancer. This hypothesis will have to be assessed in future studies. With regard to N-staging, PET/MRI does not seem to provide a considerable benefit as compared with PET/CT but provides similar N-staging accuracy when applied as a whole-body staging approach. M-staging will benefit from MRI accuracy in the brain and the liver. The purpose of this review is to summarize the available first experiences with PET/MRI and to outline the potential value of PET/MRI in oncologic applications for which data on PET/MRI are still lacking.

Learning Objectives: On successful completion of this activity, participants should be able to describe (1) the advantages and disadvantages of PET/MRI in oncologic applications in comparison to conventional imaging methods and PET/CT; (2) the limitations of PET/MRI compared with invasive staging procedures (biopsy); and (3) the metabolic-anatomic imaging procedure of choice (PET/MRI vs. PET/CT) based on tumor entity and location.Financial Disclosure: The authors of this article have indicated no relevant relationships that could be perceived as a real or apparent conflict of interest. CME Credit: SNM is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to sponsor continuing education for physicians. SNM designates each JNM continuing education article for a maximum of 2.0 AMA PRA Category 1 Credit. Physicians should claim only credit commensurate with the extent of their participation in the activity.For CE credit, participants can access this activity through the SNM Web site (http://www.snm.org/ce_online) through August 2013.With integrated whole-body PET/MRI, a novel metabolicanatomic imaging technique recently has been introduced into clinical practice. This review addresses PET/MRI of bone tumors, soft-tissue sarcoma, melanoma, and lymphoma. If PET/ MRI literature is not yet available for some types of tumors, potential indications are based on available PET/CT and MRI data. PET/MRI seems to be of benefit in T-staging of primary bone tumors and soft-tissue sarcomas. With regard to N-staging, PET/MRI can be considered similarly accurate to PET/CT when applied as a whole-body staging approach. M-staging will benefit from MRI accuracy in the brain, the liver, and bone. Imagi ng plays a key role in diagnosis and staging in oncology. Evaluation of local tumor extent and detection of potential locoregional lymph node or distant metastases according to the periodically revised standardized TNM cancer staging system (1) directly affects patient care by defining the most suitable therapy. With integrated wholebody PET/MRI, a new metabolic-anatomic imaging modality has been introduced into clinical practice. Despite the fact that the solution of basic problems, such as adequate MRI-based attenuation correction, is still a work in progress (2), reports on initial clinical experiences with PET/MRI in oncology are already available. In this second part of our review on PET/MRI in oncologic applications, we summarize the available first experiences with PET/ MRI in bone tumors, soft-tissue sarcoma, melanoma, and lymphoma. In fields where PET/MRI data are lacking, we outline the potential role of PET/MRI on the basis of the PET/CT and MRI literature. To provide further information on PET/MRI, we refer to our own unpublished experiences with PET

Integrated PET/MRI does not provide diagnostic advantages for local tumor staging of breast cancer patients in comparison to MRI alone. Positron emission tomography/MRI and MRI enable an improved determination of the local tumor extent in comparison to PET/CT, whereas all 3 imaging modalities offer a comparable diagnostic performance for the identification of axillary disease.