SNMMI 2014: Sentinel lymph node SPECT/CT spots more cancer

ST. LOUIS— Society of Nuclear Medicine and Molecular Imaging (SNMMI)  leadership and a panel of experts announced today the most striking research being presented at the 2014 SNMMI Annual Meeting at the America’s Center convention center from June 7-11. This included the abstract of the year outlining how sentinel lymph node SPECT/CT imaging bests lymphoscintigraphy.

Following a range of tracks from cardiovascular imaging, instrumentation, molecular targets, neurosciences and oncology, the science presented this year represents everything from developments in PET/MR to clinical study applications ranging from Alzheimer’s to low back pain and novel biomarkers for advanced cancers.

The abstract of the year award went to a comprehensive international study that demonstrates the superiority of SPECT/CT over planar lymphoscintigraphy for the detection of sentinel lymph node malignancy in a variety of cancers. The research was conducted by Thomas N.B. Pascual, MD, from the section of nuclear medicine and diagnostic imaging and division of human health of the International Atomic Energy Agency in Vienna, Austria, and colleagues.

“We found significantly more sentinel lymph node involvement with SPECT/CT, which altered surgical planning for many of our patients—a finding that was repeated across all malignancies and clinical institutions,” Pascual said in an official statement. “These results could potentially inform new clinical practice and shape appropriate use of SPECT/CT imaging for patients selected for surgery.”

The results were replicated across cases of prostate and cervical cancer, breast carcinoma, melanoma and others. The value of improved sentinel lymph node imaging is centered on disease staging and surgical mapping. A slight change in either can significantly alter patient management.

The data showed how SPECT/CT found 13 percent more cancers in sentinel nodes (2,165 nodes detected with SPECT/CT compared to 1,892 with planar lymphoscintigraphy). Additionally, SPECT/CT caught 11.5 percent more sentinel nodes in cases of melanoma (602 nodes detected with SPECT/CT compared to 532 nodes with planar lymphoscintigraphy). For cases of pelvic cancer, hybrid SPECT spotted 29.2 percent more nodes than lymphoscintigraphy (195 compared to 138, respectively).

Altered clinical decisions as a result of SPECT/CT results were widespread. For example, 64.1 percent of surgical planning underwent a significant change and 37 percent of surgical planning for melanoma patients changed. A high mismatch, 50 percent, was found between SPECT/CT and lymphoscinitigrapy for lymphatic regions and sentinel nodes of the pelvis. This was attributed to deep lymphatic drainage and specific location of pelvic sentinel nodes.