June 1, 2010
Fox Chase Researchers To Present At American Urological Association
Fox Chase Cancer Center researchers will present three abstracts at the 2010 annual meeting of the American Urological Association (AUA) that demonstrate progress in the use of the R.E.N.A.L. Nephrometry Scoring to characterize renal mass anatomy and allow standardization of surgical decision-making and comparison of outcomes in patients with kidney cancers.
Alexander Kutikov, M.D., working with Robert G. Uzzo, M.D., F.A.C.S., chairman of surgical oncology at Fox Chase Cancer Center, will present the findings at the AUA meeting May 29- June 3, 2010 in San Francisco.
Currently, renal oncologic surgeons have individual approaches for evaluating patient tumors to determine the course of treatment, and report tumor size as the principal variable when sharing patient history and outcomes. The Nephrometry Score, however, captures additional information, providing physicians and researchers "“ for the first time "“ a classification system that can be used to objectify surgical decision making. In fact, the Nephrometry Score not only affords a tool that is clinically useful, but also provides an index by which investigators can measure surgical performance and make meaningful performance comparisons between surgeons and institutions.
The Nephrometry Scoring system describes renal masses based on critical anatomical features: Radius/diameter; Exophytic/endophytic properties; Nearness of the tumor to the collecting system or sinus; Anterior or Posterior; Location relative to the polar lines; and Hilar location, abutting the main artery or vein.
"In a field where there are no standards of practice and no current reproducible tools for evaluating subjective decisions such as what type of surgery to perform and when, a system like Nephrometry can put renewed power in both physicians' and patients' hands," says Kutikov.
Standardization of Practices
To investigate the full capabilities of Nephrometry, researchers retrospectively applied R.E.N.A.L. Nephrometry Scores to patients that were treated between the years 2000-2009 from Fox Chase's Kidney Cancer Database "“ one of the world's largest kidney cancer databases with clinical information from more than 700 surgical patients. Researchers then compared the decisions surgeons made in choosing treatment for those tumors with tumor complexity as captured by the Nephrometry Score. The study showed those tumors with lower R.E.N.A.L. Scores (specifically due to the tumor's anatomical attributes) were more often placed on active surveillance compared to those with higher Scores, which were treated with immediate surgery. Such data provide evidence that Nephrometry is an accurate means of capturing the subjective thought process of determining treatment strategy.
"We're showing through these studies that physicians have always been making decisions based on the anatomy of tumors, but now we have a way of quantifying that process," says Kutikov. "And that allows us to effectively share information from institution to institution, opening doors and facilitating the kinds of conversations that lead to improved patient care."
Objective Surgical Decision-Making
Patients with renal masses have a variety of surgical options available to them based on the complexity of their tumors. In a second recent study, Daniel Canter, M.D., working with Uzzo, and their colleagues analyzed the surgical treatment of tumors in the Kidney Cancer Database for which Nephrometry Scores were available. Surgeries on those tumors included minimally-invasive partial, open partial, minimally-invasive radical, and open radical nephrectomies. Again, the team observed that the Nephrometry Score properly reflected which procedure was best for each tumor, suggesting that the system can help standardize surgical procedure selection. This key learning comes as a response to a growing interest in the field to incorporate quantifiable data into surgical practice to promote optimal patient outcomes.
With the advent of improved imaging, oncologists are diagnosing an increasing number of kidney tumors, which is leading to a growing number of surgeries. However, the mortality rate of kidney cancer "“ one of the deadliest cancers "“ is still slightly increasing, suggesting that a number of patients are not benefiting from today's practices. The incongruity of the two trends suggests an overtreatment of patients. In fact, 20% of the kidney tumors currently being removed from patients are benign and would not have required surgery.
"Imaging, as it stands now, does not allow a physician to predict the pathology of a tumor, which is why we are unnecessarily removing so many benign masses," says Kutikov. "While data suggest differences in pathology occur based on tumor size, depth and location, without the Nephrometry Score investigators are not able to quantify those variables. In our third study, we verified that Nephrometry can be used to give physicians insight into a tumor's pathology, specifically its grade and histology. Such information is very powerful."
Learning a tumor's pathology can allow doctors to move toward a predictive model for shaping renal oncology care. A surgeon can input the data gathered on the five characteristics the R.E.N.A.L. Nephrometry Score measures and compute an overall risk-factor for benign or high risk disease.
"Similar to what the Gleason Score has done for prostate cancer, the R.E.N.A.L. Nephrometry Score can gauge severity and guide therapy for kidney cancer," says Kutikov. "It's even possible we could develop this system to the point where a patient could ask, 'What's my Nephrometry Score?' and seek care at an institution with a particular expertise of handling cases in the same range."
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