Applications of PET-CT are expanding as is the technology's ability to improve patient care (and often at less overall cost). Educating other specialties about the impact and appropriate role of PET-CT is a priority today as is surmounting somewhat complicated reimbursement. IT is the missing link that is proving to be a challenge with many PET-CT scanners not yet talking to PACS.
PET-CT is proving its might in oncology. Approved indications have expanded from the original cache - lung, colon, esophageal and metastatic breast cancer and lymphoma - to include others such as locally advanced breast cancer, cervical, endometrial and ovarian cancer. The hybrid technology is improving patient care, facilitating more accurate staging to allow clinicians to more appropriately treat cancer. At the same time, studies show that PET-CT does save money in the long run by avoiding futile surgeries and determining whether or not a patient is responding to chemotherapy.
Later this year, the Centers for Medicare and Medicaid Services (CMS) will launch the PET Registry. Participating institutions can scan any patient with a biopsy-proven cancer. The national data collection effort will hopefully demonstrate the utility of PET and lead to an open approval for PET, similar to CT, says Medhat Osman, MD, PhD, director of PET at St. Louis University (St. Louis, Mo.).
Despite all of the positives, PET-CT faces some challenges. Reimbursement remains sticky; CMS and private payors have not yet adopted standard processes. Training of radiologists and nuclear medicine physicians also is a work-in-progress. Although oncologists have made great strides in understanding PET technology, educating referring physicians about functional imaging remains a priority, says Peter Conti, MD, PhD, president of Society for Nuclear Medicine. IT is another hurdle. Communication and integration between PET-CT scanners and other imaging and IT equipment can be problematic, and DICOM for nuclear medicine is undeveloped.
Flexing its muscles
"PET-CT offers the best of both worlds by acquiring both anatomical and functional information nearly simultaneously," poses Osman, who uses Philips Medical Systems 16-slice Gemini PET-CT for oncology imaging. PET and CT images complement each other, providing a more comprehensive picture of the extent of disease in many types of cancer. As PET-CT demonstrates its utility, PET centers have added multiple new indications such as locally advanced breast, ovarian, endometrial and cervical cancer.
"PET-CT with FDG can really help improve diagnostic and staging capabilities [for Medicaid-approved indications]. In about 30 to 40 percent of cases, PET-CT with FDG adds information that really alters patient treatment," explains Ronald Korn, MD, director of nuclear medicine and PET-CT imaging for Scottsdale Medical Imaging (Scottsdale, Ariz.). Korn has relied on GE Healthcare's Discovery LS PET-CT scanner as a functional go-to modality for three years.
A classic example of a treatment plan altered by a PET-CT scan is the advanced lung cancer patient. The current data suggest that the best treatment for advanced lung cancer (Stage III disease) is chemotherapy and radiation therapy followed by surgery. Conventional anatomic imaging has limited utility for staging lung cancer patients, but PET-CT has great sensitivity in deciding who should be a surgical candidate and who would be better served with chemotherapy and radiation first. Indeed PET-CT can alter staging in up to 30 percent of the patients and provide additional information in about 40 percent of patients compared to conventional imaging. If after therapy, a follow up PET-CT shows response to treatment then a patient can proceed to surgery. If the follow-up PET-CT scan shows little improvement then the oncologist can resort to second line drugs or palliative care.
Similarly, PET-CT can provide information to help clinicians determine the best treatment regimen for patients with locally advanced breast cancer. The nuclear medicine division at New York University School of Medicine in New York City, which relies on a Siemens Medical Solutions biograph 6 PET-CT scanner, now sees breast cancer patients earlier in the disease process, says Elissa Kramer, MD, director of the division of nuclear medicine. Kramer explains, "When a patient presents with locally advanced breast cancer, it's important to know the extent of disease, and when a patient is treated with adjunctive chemotherapy,