“Routine preoperative PET imaging led to a significant reduction in unnecessary surgery for non-small cell lung cancer (NSCLC), a review of almost 1,000 cases showed.
“Overall, the rate of unnecessary operations, defined as discovery of metastatic disease during surgery, decreased by 13%, which did not achieve statistical significance, according to Steven Zeliadt, PhD, of the Veterans Affairs Medical Center in Seattle, and co-authors. After adjustment for confounding factors, however, unnecessary operations occurred almost 50% less often with preoperative PET imaging.”
Editor’s Note: PET imaging is already routinely done before many (if not most) lung cancer surgeries.
Fluorodeoxyglucose-positron emission tomography (FDG-PET) scans may be able to detect early-stage non-small cell lung cancer (NSCLC) patients who are at high risk of treatment failure after stereotactic body radiation therapy (SBRT). A retrospective study examined patients with early-stage NSCLC who were ineligible for or refused surgery and were instead treated with SBRT. Patients with lower FDG-PET readings prior to SBRT treatment survived longer, and those whose FDG-PET readings changed more after SBRT were less likely to experience treatment failure. FDG-PET scans may therefore help identify which patients are at lower or higher risk of recurrence; high-risk patients may opt for additional treatment and/or more frequent surveillance after treatment. FDG-PET has shown similar predictive value in early-stage NSCLC treated with surgery.
Accurately ‘staging’ small cell lung cancer (SCLC), that is, determining its extent and spread in a patient, is crucial in choosing treatment. One year after treatment guidelines began recommending positron emission tomography – computed tomography (PET-CT) instead of bone scans for the initial evaluation of all newly diagnosed SCLC patients, researchers confirmed that the new staging method improved outcomes. A study of SCLC patients diagnosed with limited-stage disease (ie, cancer that is confined to only one lung or its immediately surrounding tissue) showed that those who had received PET-CT staging before their treatment had higher 3-year survival rates (47% vs 19%) than those who did not.
The standard imaging practice for detecting prostate cancer that returns after treatment, called recurrent prostate cancer, combines positron emission tomography (PET) with computed tomography (CT), known as PET/CT. In a recent clinical study researchers from the Technical University Munich in Germany, compared PET/CT to PET combined with magnetic resonance (MR), known as PET/MR. The study involved 31 patients with recurrent prostate cancer and found that PET/MR detected more areas of metastatic tumors, and allowed for more precise mapping of tumors, than PET/CT. The researchers say PET/MR can be considered an alternative to PET/CT, particularly when small tumors are involved. The US FDA approved the first PET/MR device in 2011.
A recent clinical study compared two different imaging methods for detecting prostate cancer in 31 patients who had disease that returned despite treatment. The imaging systems both use positron emission tomography (PET) combined with either magnetic resonance imaging (MRI) or computed tomography (CT) to detect prostate cancer cells that have spread to different parts of the body. PET combined with MRI (PET/MRI) found more areas of metastatic prostate cancer tumors than PET combined with CT (PET/CT). The lead scientist involved in the study says PET/MRI has higher detection rates and more precisely locates recurrent tumors, which could help doctors tailor specific treatments for patients.
Stage Ia non-small cell lung cancer (NSCLC) is commonly treated with surgery alone. However, the cancer frequently recurs, and only 67% of stage Ia NSCLC patients survive for 5 years or more. Adjuvant chemotherapy (chemotherapy given as a secondary treatment in addition to surgery) may increase survival, but also has severe toxic side effects. Therefore, it is important to identify stage Ia patients with high risk of recurrence, for whom the benefits of adjuvant chemotherapy would outweigh the drawbacks. A retrospective analysis of stage Ia NSCLC patients found that those with positive results from a scanning technique called a fluorodeoxyglucose PET (positron emission tomography) scan (FDG-PET) had significantly lower rates of survival. Patients with positive FDG-PET results may, therefore, be good candidates for adjuvant chemotherapy.
A phase III study evaluated two osteoporosis drugs, denosumab and zoledronic acid, for the treatment of skeletal problems in patients with bone metastases in castration-resistant prostate cancer (CRPC). The average time to first bone-related adverse event was 20.7 months with denosumab and 17.1 months with zoledronic acid, suggesting that denosumab was more effective in this group.
New findings from two prostate cancer trials will be presented at the American Society of Clinical Oncology Annual Meeting. One trial determined that men with advanced prostate cancer who receive intermittent hormone therapy survive an average of 5.1 years compared to 5.8 years for men who receive therapy continuously. The second trial determined that abiraterone (Zytiga) in combination with prednisone (a steroid) was effective for the treatment of castration-resistant prostate cancer (CRPC) in patients who have not yet received chemotherapy. Abiraterone is currently approved for patients who have not responded to chemotherapy.
A recent study evaluated the effects of finasteride (sold as Proscar) on the usefulness of prostate-specific antigen (PSA) screening to detect prostate cancer. Researchers determined that treatment with finasteride may differentiate individuals who have a rise in PSA due to cancer from those who have a rise due to other causes, such as benign enlargement and inflammation. The combination of finasteride with PSA to detect prostate cancer may decrease the rate of unnecessary biopsies.