Posts Tagged ‘nuclear’

New diagnostic, therapeutic techniques show potential for patients with metastasized melanoma

Malignant melanoma is the fifth most common cancer in men and the sixth most common cancer in women, and its incidence rate is increasing rapidly. It accounts for nearly 80 percent of all deaths related to cutaneous cancer. When discovered early, localized melanoma can be cured by surgical removal. However, this cancer displays a strong tendency to metastasize and has very low survival rates for patients, with fewer than five percent surviving longer than five years.

In the study "123I-BZA2 as a Melanin-Targeted Radiotracerfor the Identification of Melanoma Metastases: Results and Perspectives of a Multicenter Phase III Clinical Trial," researchers developed a specific single photon emission computed tomography (SPECT) radiopharmaceutical for malignant melanoma — 123I-BZA2. Imaging of patients with metastasized melanoma was then performed with both 18F-FDG positron emission tomography/computed tomography (PET/CT) and 123I-BZA2 SPECT to compare the accuracy in staging and restaging.

Eighty-seven patients were examined with a total of 86 metastatic lesions. In the analysis of lesions, the sensitivity for 18F-FDG for diagnosis of melanoma metastases was higher than that of 123I-BZA2 (80 percent vs. 23 percent). The specificity of 18F-FDG, however, was lower than 123I-BAZ2 (54 percent vs. 86 percent). The sensitivity and specificity of 123I-BAZ2 for the diagnosis of melanin-positive lesions were 75 percent and 70 percent, respectively.

"We have demonstrated that 123I-BZA2 tumor accumulation was clearly correlated to melanin content of the melanoma metastases. Thus, 123I -BZA2 could be theoretically used for the diagnosis of melanoma metastases," said Florent Cachin, MD, PhD, lead author of the study. "However, given its low sensitivity due to the high proportion of non-pigmented lesion in the natural course of metastatic melanoma, 123I- IBZA2 cannot be used for melanoma staging. Such results could appear discouraging, but the concept of melanin targeting may offer a real opportunity for therapy."

In the study "Radiopharmaceutical Therapy of Patients with Metastasized Melanoma with the Melanin-Binding Benzamide 131I-BA52," the first use of a melanoma-seeking agent for therapeutic application was analyzed. Researchers used a theranostic approach in which the same molecule was given first as a diagnostic isotope (123I-BA52) to identify the patients possibly profiting from therapy, and then as a therapeutic radiopharmaceutical (131I-BA52) for those patients who would benefit. Twenty-six patients were imaged with 123I-BA52, and nine patients were selected for therapy with 131I-BA52.

Some of the patients treated with 131I-BA52 were found to have a survival rate of more than two years. Researchers also found that higher treatment doses would have been tolerated in these patients, as only moderate side effects were observed. "We believe that the tracer could be useful in the setting of a combination therapy in patients with metastasized melanoma, especially when applied in earlier stages of the disease where the melanin production is higher as compared to later stages of the disease," noted Uwe Haberkorn, MD, lead author of the study.

Even though new treatments are now available, the prognosis for patients with metastatic melanoma remains very poor. "Innovative strategies are necessary to improve patients’ survival. Research focused on innovating targeted-therapy reflects modern oncology, as new theranostic concepts. This strategy nicely illustrates the future of nuclear medicine oncology," said Cachin.

source : http://www.sciencedaily.com/releases/2014/01/140107170905.htm

Nuclear medicine therapy increases survival for patients with colorectal cancer, liver metastases

Colorectal cancer is the third most commonly diagnosed type of cancer worldwide in men and the second in women, and it is also the third most common cause of death. In approximately 50 percent of patients, metastases to the liver are present at diagnosis or during follow-up, which account for a large portion of morbidity and mortality in patients.

A structured review was performed by researchers to gather all available evidence on radioembolization for the specific group of patients with colorectal cancer liver metastases. "Although quite some reviews are printed on the subject of radioembolization, we felt that a structured and comprehensive review on survival and response data for these patients was lacking," said Charlotte E.N.M. Rosenbaum, PhD, lead author of the study "Radioembolization for Treatment of Salvage Patients with Colorectal Cancer Liver Metastases: A Systemic Review."

Researchers reviewed a total of 13 articles on Y-90 radioembolization as a monotherapy and 13 articles on Y-90 radioembolization as a combined with chemotherapy. Among the studies, disease control rates (i.e., complete response, partial response and stable disease) ranged from 29-90 percent in the monotherapy studies, which involved 901 patients. In the studies in which Y-90 radioembolization was combined with chemotherapy, involving 472 patients, disease control rates ranged from 59-100 percent.

"From the studies included in this systematic review, survival proportions of approximately 50 percent were found. Therefore, in this group of salvagecolorectal cancer liver metastases patients who otherwise have no regular treatment options and a life expectancy of less than six months, Y-90 radioembolization seems to be a hopeful treatment option," noted Rosenbaum.

She continued, "Our paper shows all published data on this subject from the first randomized trial onwards. Furthermore, we have determined 12-month survival proportions for all included articles to provide a better overview and to better allow for comparisons. Finally, this overview of the literature shows which topics have not been the focus of much research and may thus be interesting for further work."

source : http://www.sciencedaily.com/releases/2013/11/131106132029.htm