Breast and Prostate Cancer Detection Enhancements
The U.S. National Institutes of Health (NIH) are funding new research that aims to develop novel imaging techniques to detect both breast and ovarian cancers early and more accurately. Cancer is typically difficult or even impossible to see, which is why cancer detection as well as diagnosis (let alone treatment) has historically proven to be so challenging. A separate study has already been published in Radiology covering the amalgamation of synthetic 2-D imaging and digital breast tomosynthesis (DBT), and it observes measurably improved rates of cancer detection in comparison to the usual, full-field digital mammography (FFDM).
As it so happens, “This is an exciting time in radiology,” according to Heidelberg University researcher and professor Frederik Giesel in Germany. New agents used for prostate imaging are expected to drastically enhance the ability to detect cancerous legion locales, and Giesel anticipates, as do many others in the field today, that this will make radiotherapy much more precise in its targeting in the very near future. One of these new agents is 18F-PSMA-1007, which is markedly different from other agents currently used in prostate imaging processes.
Giesel explained in early December during his presentation at the Radiological Society of North America 2017 in Chicago—a conference that summits annually—that three different studies demonstrate this. “[18F-PSMA-1007] has a longer shelf life than the others and minimal kidney clearance, meaning that urinary excretion of it is minimal,” Giesel explained. “18F-PSMA-1007 is the first traer that has a different elimination route, which I would say is an advantage” and a rather significant one at that.
Even more important than this is the fact that 18F-PSMA-1007 has a greater tumor tissue uptake than other tracers. It has a tumor-to-background ratio that greatly improves the detection of lymph node metastases in comparison to other agents. “We see advantages of diagnostic performance in this tracer,” Giesel says. He published a study earlier this year that had already illustrated 95 percent sensitivity to small lymph node metastases on the part of 18F-PSMA-1007. In a newer study, though, Giesel and his team analyzed its diagnostic use value, scrutinizing biodistribution across tumors and normal organs in seven different patients.
The participants in the study had recurring prostate cancer, and the study took stock of the sizes of their lesions. They administered 18F-PSMA-1007 to patients and put those participants through PET-CT scanning twice—once only an hour after injecting them with 18F-PSMA-1007 and again three hours after injection. They successfully detected local recurrence in two patients with prostate-specific antigen (PSA) levels of 3.6 and 1.9 ng/mL. They also detected lymph node metastases in two others with PSA levels of 2 and 0.16 ng/mL, and they found bone metastases in another participant whose PSA level was 3.8 ng/mL.
“Everyone is excited,” said Stanford University’s Andrei Iagaru, a researcher at Stanford’s medical college. “We are now able to identify prostate cancer early and accurately.” That’s what doctors and engineers in St. Louis, Missouri (U.S.) at Washington University have been aiming to accomplish for breast cancer since last year. They tested imaging-based techniques in 2016 to see if those techniques could bring a more in-depth scan of cancer because it would empower women so that they can make more informed decisions about treatment options from the very beginning. It’s expected to make all the difference for prostate cancer patients based on the advantages afforded by 18F-PSMA-1007, and the same advantages are just as necessary for breast and ovarian cancers as they are for prostate cancer.
Lots of cancers remain undetected until they reach late stages, which makes it very hard to successfully treat patients. This makes patients much more vulnerable, and lots of the testing methods currently employed lead to risky surgeries predicated on false positives. This is particularly detrimental for breast cancer patients, as referenced in a study recently published in Annals of Surgery, which found rates of contralateral prophylactic mastectomy more than tripled between 2002 and 2012; that’s the full removal of both breasts. This trend was especially concerning because it was observed among younger women, which indicates that many women may have undergone these surgeries unnecessarily given that only a third or so of women in the study actually showed high-risk factors for breast cancer.
The study published in Radiology came out in the middle of this month, and its authors studied over 16,000 different, asymptomatic women between the ages of 50 and 69, all of whom underwent both synthetic 2-D mammography and DBT in recent history (as early as April 2015 and as late as March 2016). They compared the resultant data with over 14,000 women who, in roughly the same segment of time, received full-field digital mammographies (FFDMs). Ultimately, they found cancer detection rates for the combined efforts of DBT and synthetic 2-D imaging to be 9.3 for every 1,000 exams. FFDMs, on the other hand, proved to only manage 5.41 per 1,000 exams.
“There was evidence of improved cancer detection with DBT plus synthetic 2-D imaging across age groups, with significant differences for women older than 55 years, further highlighting the effectiveness of DBT in terms of cancer detection for women in this age group,” according to Francesca Caumo, lead author from Ospedale di Marzana in Verona, Italy. She and her team added, “DBT plus synthetic 2-D imaging also significantly improved cancer detection in all density-stratified analyses.”
[리서치페이퍼=Cedric Dent 기자]