2021 Archives

PCa Commentary | Volume 160 – December 2021

Posted by Edward Weber, MD | Dec 2021

This Commentary looks at gene mutations in the BRCA Family and PARP inhibition therapy for advanced prostate cancer.

Emerging Role of PSMA Imaging

Posted by Steven P. Rowe, MD, PhD | Dec 2021

Steven P. Rowe, MD, PhD, Associate Professor of Radiology and Radiological Science at Johns Hopkins University in Baltimore, Maryland, discusses the emerging role of prostate-specific membrane antigen (PSMA) imaging. He defines PSMA as a transmembrane carboxypeptidase highly expressed in prostate cancer cells. This expression has been observed in over 95 percent of prostate cancer tumors, with a direct correlation between expression levels and tumor aggressiveness. Due to this, Dr. Rowe asserts that PSMA is an excellent target for molecular imaging of prostate cancer. Dr. Rowe displays a PSMA structure and activity diagram and explains that PSMA positron emission tomography (PET) has moderate sensitivity and very high specificity for pre-operative nodal staging, high detection efficiency for sites of biochemical recurrence (BCR), and can effectively guide focal therapy for oligometastases and is effective in selecting patients for endoradiotherapy. He then discusses each of these in more detail, highlighting data from a study that evaluated the diagnostic performance of PSMA-targeted 18F-DCFPyL PET/computerized tomography in the preoperative staging of men at high risk for harboring metastatic prostate cancer. Dr. Rowe shows data on PSMA-based therapy and points out that for patients with more widespread metastatic disease, treatment may include PSMA inhibitors such as lutetium-177. Dr. Rowe expects that lutetium-based PSMA therapy will be approved by the FDA and become part of the standard of care for patients with widespread metastatic disease. Dr. Rowe then outlines lingering questions about PSMA PET imaging, including how prognostic findings may look for different patient populations, how doctors should follow response to therapy given that decreasing androgen signaling leads to increase in PSMA expression, and what role artificial intelligence (AI) is going to play. Dr. Rowe illustrates data from the Observation vs. Stereotactic Ablative Radiation for Oligometastatic Prostate Cancer (ORIOLE) trial results for oligometastatic disease, pointing out that patients who had all lesions visible on a PSMA scan treated had better outcomes than those who only had a subset of their PSMA-positive lesions treated. Dr. Rowe predicts that in the near term, AI will provide lesion classification, whole-body tumor burden assessments, and prognostication and decision-making based on scan findings and clinical data. In conclusion, Dr. Rowe explains that, based on existing studies, there are already multiple indications for diagnostic PSMA-based imaging, with the caveat that researchers are just starting to understand PSMA-targeted PET findings as imaging biomarkers, and currently there are still questions about the interface of PSMA PET with AI.

The Latest Dope on Medical Marijuana

Posted by Neil H. Baum, MD | Dec 2021

Grand Rounds in Urology Contributing Editor Neil H. Baum, MD, Professor of Urology at Tulane Medical School, discusses the latest research on medical marijuana, noting that it is increasingly popular with patients and that almost all physicians, including urologists, should expect questions about it. He gives a brief history of cannabis, from its use as an herbal medicine in 500 BCE, to its criminalization in 1937 and, eventually, to its legalization for both medical and recreational uses over the last few decades. Dr. Baum then defines several terms, explaining the difference between cannabidiol (CBD), which is not psychoactive and has anti-inflammatory properties, and tetrahydrocannabinol (THC), which is psychoactive and increases appetite. He lists the conditions marijuana is purportedly beneficial for including chronic pain, alcohol and drug addiction, insomnia, depression, post-traumatic stress disorder, social anxiety, nausea and vomiting associated with chemotherapy, gastrointestinal disorders, multiple sclerosis, and certain forms of epilepsy. Dr. Baum notes that while there is some evidence supporting marijuana’s benefits for several of these conditions, randomized controlled trials are needed to substantiate many claims.

Updates in Treatment of Renal Cell Carcinoma

Posted by Robert Dreicer, MD, MS, MACP, FASCO | Dec 2021

Robert R. Dreicer, MD, MS, MACP, FASCO, Associate Director for Clinical Research and the Deputy Director of the University of Virginia Cancer Center, discusses the challenges in picking an optimal front-line regimen for the treatment of renal cell carcinoma and the impact of adjuvant immuno-oncology (IO) therapy. He cites data from four trials (CheckMate 214, Keynote-426, CheckMate 9ER, and CLEAR) before outlining the challenges in choosing an optimal front-line regimen. Dr. Dreicer points out that there is no comparative data currently available before explaining that tyrosine kinase inhibitors (TKIs, formerly the standard of care for kidney cancers) are toxic, challenging drugs that impact a patient’s quality of life. Dr. Dreicer outlines the therapies available today, including ipilimumab plus nivolumab (IPI-NIVO) which he characterizes as challenging for the first couple of months but well-tolerated in the last ~20 months during which patients undergo a maintenance regimen of nivolumab. He points out that treatment can be stopped after two years for patients that respond well. Dr. Dreicer asserts there is no equivalent conclusion with a TKI checkpoint. Dr. Dreicer then turns his discussion to the KEYNOTE-564 study on pembrolizumab versus placebo as post-nephrectomy adjuvant therapy for patients with renal cell carcinoma. He outlines the study design and eligibility criteria before displaying the disease-free survival (DFS) data showing the adjuvant therapy resulted in a 32 percent reduction in recurrence or death. Dr. Dreicer argues that for patients who can access an IO-based regimen, IPI-NIVO should be the standard of care, advising that while there is not one “right answer” to the optimal treatment question, practitioners ought to use one regimen, figure out what it’s toxicities are, and learn how to use it well. Dr. Dreicer then outlines questions that will emerge if an adjuvant checkpoint inhibitor becomes a standard of care, citing disruption to the front-line paradigm, the role of subsequent IO therapy, progression while on adjuvant therapy, and progression following adjuvant therapy. Dr. Dreicer emphasizes the need for other trials and the need to develop therapeutics that work in immune-checkpoint resistance.

Fear and Frustration Among Women with Recurrent UTIs

Posted by Ja-Hong H. Kim, MD | Dec 2021

In conversation with A. Lenore Ackerman, MD, PhD, Assistant Professor of Urology and Director of Research in the Division of Female Pelvic Medicine and Reconstructive Surgery at the University of California, Los Angeles, Ja-Hong H. Kim, MD, Associate Professor in the Division of Pelvic Medicine and Reconstructive Surgery at the University of California, Los Angeles, and Victoria C. Scott, MD, Associate Program Director of the FPMRS Fellowship at Cedars-Sinai Medical Center, discuss a recent study of the experience of women with recurrent urinary tract infections (rUTIs). Dr. Scott explains that 29 women were recruited to participate in 1 of 6 focus group discussions to investigate the perspective of women suffering from rUTIs. She then lists some preliminary themes from the discussions with the women, including fear of development of antibiotic resistance, widespread knowledge of the collateral damage from antibiotics, concern about taking unnecessary antibiotics, anger at physicians for “throwing” antibiotics at them, a feeling that the medical profession underestimates the impact of rUTIs, a need for research on nonantibiotic options for prevention and treatment, and resentment towards the medical system for not dedicating more research efforts to providing more timely diagnosis. Dr. Scott synthesizes these themes into two emergent concepts: fear about the overuse of antibiotics and frustration at the medical system for not providing alternative treatments or taking rUTI symptoms seriously. Dr. Kim then notes that this initial study has produced two additional studies on the current management of rUTIs that take expert and personal care provider experiences into account. Dr. Ackerman highlights the importance of data capturing that patients are not seeking antibiotics necessarily in the way doctors assume they are, though Dr. Kim does add the caveat that the women in the study were a relatively homogeneous group of college-educated white women. Dr. Ackerman also muses that the attitudes expressed in this study suggest that this population may be interested in a vaccine for rUTIs. Drs. Ackerman, Scott, and Kim conclude by noting that the study made evident the importance to patients with rUTIs of focusing on their experience rather than merely the clearance of bacteria.