ASCO – What's New in GU?

Prevalence and Clinical Outcomes of Advanced Prostate Cancer Patients with Inherited DNA-Repair Mutations

DNA Helix_NCI Collaborative work has shown that approximately 12% of men with advanced prostate cancer have inherited, or germline, DNA-repair mutations that disrupt the normal function of the genes involved in repairing damaged DNA. Somatic alterations in DNA-repair pathways are also common in prostate cancer, particularly in late-stage disease. Somatic alterations affect only tumor cells, but are not inherited or passed on. Inherited mutations in DNA-repair genes – such as BRCA2, ATM, and CHEK2 – are associated with an increased risk of several other cancers as well as prostate cancer, including breast, ovarian, and pancreatic cancer. In particular, mutations in BRCA2, associated with 1.8% of overall prostate cancer cases, have been associated with more aggressive prostate cancer characteristics and worse outcomes, including increased risk of recurrence and poorer overall survival rates.

As a result of the increasing number of men with these types of mutations, the National Comprehensive Cancer Network (NCCN) guidelines have recently changed, now recommending genetic testing for all men with metastatic prostate cancer.

Weill Cornell Medicine

“Genetic testing for inherited mutations may provide some men with prognostic information about their prostate cancer risk,” says Dr. Scott Tagawa, Director of the Weill Cornell Medicine and NewYork-Presbyterian Genitourinary (GU) Oncology Program. “Even more importantly, genetic testing can also be used to inform screening of family members and may increasingly inform precision-medicine based approaches to manage the disease using specific molecular features such as DNA-repair genes,” says Dr. Tagawa.

How do Inherited Mutations Impact Treatment?

Clinical research studies are continually being conducted to investigate new ways to treat advanced prostate cancer patients with germline DNA-repair mutations since these patients comprise a unique subset of patients. Currently, little has been known about whether DNA-repair mutation status impacts benefit from standard therapies for the disease and this is just one area that needs to be researched in order to specifically tailor treatment options for this subset of patients.

Weill Cornell Medicine and NewYork-Presbyterian’s Drs. Himisha Beltran, Scott Tagawa and David Nanus, along with collaborators from around the globe, address this in research published today in the high impact factor journal European Urology and simultaneously presented at the American Society of Oncology (ASCO) 2018 Genitourinary (GU) Cancers Symposium by Dr. Misha Beltran. The researchers reviewed 390 medical records of patients who previously participated in a New England Journal of Medicine (NEJM) study examining men with advanced prostate cancer with known germline DNA-repair mutations and those without these mutations. The goal of the research was to determine whether germline mutations in DNA-repair genes impact the benefit of standard therapies for metastatic prostate cancer, such as docetaxel chemotherapy and androgen receptor signaling inhibitors abiraterone acetate and enzalutamide. Results showed that all patients appeared to benefit from standard therapies similarly to other metastatic prostate cancer patients, regardless of germline mutation status.

“The data suggest that metastatic prostate cancer patients with inherited mutations in DNA damage repair genes, including those with BRCA2 mutation, derive similar benefit from standard of care therapies in terms of both response rate and progression-free survival,” says Dr. Scott Tagawa. “While we continue to investigate additional agents thought to preferentially benefit those with DNA repair alterations, current evidence indicates that detection of any of these mutations should not prevent metastatic prostate cancer patients from receiving standard therapies including taxanes, abiraterone and enzalutamide, as standard of care treatment.”

Additionally, sophisticated genetic analysis and testing may be performed by genetic counselors and widely-available commercial testing is also available to physicians and patients. Dr. Panagiotis Vlachostergios, fellow and medical oncologist at Weill Cornell Medicine and NewYork-Presbyterian, presented research at ASCO Genitourinary (GU) Cancers Symposium focused on using a commercial 30-gene panel to test men with localized prostate cancer and advanced prostate cancer for the presence of inherited gene mutations. Out of the 17 men with localized disease and 35 men with metastatic prostate cancer, eight of 52 (15%) were found to have a germline alteration. A higher percentage of men with an inherited mutation had localized (23.5%) versus advanced disease (11.4%), though testing might have been biased towards those with family history of cancer or those diagnosed with high-grade cancer at earlier age.

Both the results published in European Urology and research presented at the 2018 ASCO GU Cancer Symposium underscore the importance of genetic testing to determine what, if any, mutations may be present in prostate cancer in order to determine the best possible treatment options. While the published data supports the use of standard therapies in those with metastatic prostate cancer who have germline DNA-repair mutations, not all patients respond to these types of treatment, demonstrating the need for alternate treatment options for this patient population. Weill Cornell Medicine and NewYork-Presbyterian are in the process of opening several clinical trials to include men with prostate cancer in need of different lines of therapy. Clinical trials testing PARP inhibitors, a drug target for cancer therapy that appears to be more effective in prostate cancer patients with DNA-repair mutations, are ongoing and may offer additional therapy options for this group of patients in the near future.

ASCO 2017: Genitourinary (GU) Oncology Highlights

Each year, the American Society of Clinical Oncology (ASCO) Annual Meeting brings together more than 30,000 oncology professionals. At this year’s meeting in Chicago, physicians and scientists presented the latest research findings in an effort to bring the best cancer treatments to patients across the United States and the world. We’ve outlined some of the genitourinary (GU) oncology highlights, broken down by disease type.

At this year’s meeting, there was also some important research presented related to communication, quality of life and survival. In a study that involved patients with GU cancers, as well as those with other types of tumors, patients were randomized to two groups: 1) a control group of standard care 2) a group to utilize a web-based patient-reported outcome questionnaire between visits. Results from any answers completed in the online system were sent to the treatment team in real time. In this study, the patients that were randomized to the online questionnaire group experienced better quality of life. In addition, these patients lived longer, with a 17% improvement in survival simply by using the online tracker reporting symptoms to their treatment team between visits. While the study was only conducted at a single institution, it underscores the importance of communicating and relaying any symptoms to your treatment team members responsible for your medical care (generally physicians, nurses and advanced practitioners).

Prostate Cancer:

The results from two large phase 3 clinical trials will lead to a change in the standard of care treatment for men with advanced prostate cancer. The LATITUDE and STAMPEDE trials investigated the addition of abiraterone and low dose prednisone to standard androgen deprivation therapy (ADT) for men with advanced prostate cancer. Similar to the unprecedented results presented at ASCO in 2014 (CHAARTED) and 2015 (STAMPEDE) with the use of docetaxel chemotherapy, a major improvement in overall survival was demonstrated, improving length of life by nearly 40%. The results from these studies will provide an additional treatment option for men presenting with advanced prostate cancer.

For men with metastatic castration-resistant prostate cancer (mCRPC), a randomized phase 2 trial demonstrated no significant differences in the efficacy, or effectiveness, of abiraterone or enzalutamide, two of the leading treatments for prostate cancer that is resistant to hormonal therapy. This research finding was consistent with most clinicians’ belief that either drug may be utilized, allowing physician and patient choice. Importantly, the study incorporated a number of interesting biomarkers using circulating tumor cell (CTC) DNA from a liquid biopsy, and the data gleaned from the DNA revealed prognostic insights about disease aggressiveness and biology. Another study showed a lack of utility to continue enzalutamide after disease progression, confirming the current practice of switching treatments after cancer growth.

Interesting data using the PARP inhibitor veliparib was presented. In a randomized phase 2 trial, the combination of veliparib and abiraterone was not better than abiraterone alone overall, but for tumors with DNA damage repair defects, there was a difference. This adds to the anticipation of results from the many ongoing randomized trials that are testing PARP inhibitors in molecularly selected patients.

Additional data was presented on genomic signatures from prostate tissue, which in combination with clinical data, are more powerful in indicating prognosis in men who receive treatment for clinically localized (low stage / early) prostate cancer.

Prostate cancer acquires resistance to systemic treatment as a result of tumor evolution and selection, but repeat biopsies to study how cancers evolve are challenging, invasive, and may be confounded by tumor heterogeneity. Dr. Himisha Beltran evaluated a non-invasive approach: whole exome sequencing of circulating tumor DNA in the blood. Additional data utilizing circulating tumor cell (CTC) counts as an early indicator of response may speed drug development. Clinical trials are currently evaluating measuring circulating tumor cell counts as a biomarker for whether or not treatments are working. This may be a better indicator than measuring levels of prostate specific antigen (PSA), the current indicator for response.

ASCO_Tagawa_Poster_PSMA — Dr. Scott Tagawa presents an update on the 177Lu-PSMA-617 clinical trial for men with metastatic prostate cancer.

Dr. Scott Tagawa presented a trial-in-progress update about the clinical trial he is leading at Weill Cornell Medicine and NewYork-Presbyterian utilizing the small molecule lutetium 177Lu-PSMA-617 to target prostate-specific membrane antigen (PSMA). PSMA is a protein abundantly expressed in 85-90 percent of metastatic prostate cancer cells, and this is the first U.S. trial of its kind. Learn more about this radionuclide therapy-based clinical trial and the eligibility criteria.

Additionally, there were many research updates presented in the area of neuroendocrine prostate cancer (NEPC), an aggressive subtype of prostate cancer that is resistant to many traditional treatment types. Dr. Loredana Puca received a Merit Award from the Conquer Cancer Foundation for her research examining the potential use of antibody-drug conjugate rovalpituzumab tesirine for treatment of NEPC. View the abstract and learn more about our open clinical trial using this antibody-drug conjugate. Dr. Himisha Beltran highlighted the significance of the loss of tumor suppressor ZFP36 in prostate cancer patients.

Prostate cancer was the first tumor type to have a cancer vaccine (sipuleucel-T) lead to longer survival, but the drug’s activity may be limited on its own. In a randomized phase 2 trial, receiving sipuleucel-T in combination with indoximod – a drug with the potential to improve immune response – kept the cancer at bay more than twice as long compared to those who received sipuleucel-T plus a placebo. This was an exciting research update showing promise for patients with prostate cancer.

New research using tumor and liquid (blood-based) biopsies demonstrated that a majority of tumors and circulating tumor cells in men with metastatic castration-resistant prostate cancer express a protein called Trop-2, justifying a targeted treatment approach. With this knowledge, we are now evaluating the safety and efficacy of IMMU-132, an immunotherapy-based drug that targets Trop-2, in an open clinical trial for men with prostate cancer.

Bladder Cancer and Other Urothelial Cancers:

ASCO_Bishoy Faltas_Talk — Dr. Bishoy Faltas presents on “Unlocking the Genome: Insights Into Risk and Response in Bladder Cancer” at the ASCO 2017 Clinical Science Symposium.

Dr. Bishoy Faltas was invited to present at the ASCO Clinical Science Symposium entitled “Expanding the Actionable Landscape: Bladder Cancer Genomics — Unlocking the Genome: Insights Into Risk and Response in Bladder Cancer.”

During this session, Dr. Faltas discussed the genomics of urothelial cancer, and highlighted the latest research describing new data on the frequency of inherited (germline) mutations as well as tumor (somatic) genomics and relationship to response to chemotherapy and immunotherapy. Patients with “upper tract” urothelial cancer (tumors arising in the kidney or ureter) in particular have a higher chance of harboring an inherited mutation. Different genomic alterations in the tumors may be separated into groups that are associated with better responses to chemotherapy and immunotherapy. This is becoming more clinically relevant as we can test for these genes and the number of treatment options is expanding.

Additionally, updated results of the KEYNOTE-045 study confirmed the overall survival benefit of the anti-PD1 immune checkpoint inhibitor pembrolizumab (Keytruda) compared to second-line chemotherapy in patients with prior platinum-based chemotherapy. Importantly, this was the first head-to-head trial to demonstrate the superiority of immunotherapy over chemotherapy in urothelial cancer.

Dr. Scott Tagawa contributed to the investigation of a novel oral targeted chemotherapeutic agent called RX-3117 in advanced bladder cancer patients. Learn more about our open clinical trial with RX-3117.

Kidney Cancer (Renal Cell Carcinoma):

Several different combination studies for the treatment of advanced renal cell carcinoma (RCC) were presented at the 2017 ASCO Annual Meeting. While some studies demonstrated promising response data, significant toxicity of some combinations underscored the importance of clinical trials and the recommendation to avoid combinations outside of the research setting, which is regulated and in which these types of side effects can be monitored. Several randomized phase III trials testing combination therapy are ongoing with results anticipated to lead to changes in standard of care.

Unfortunately, despite imaging that indicates no evidence of cancer metastases (spread), many patients are not cured with surgery alone. Treatment of many cancers incorporate the use of systemic (medical) therapy in addition to surgery to increase cure rates. For the most part, this strategy has not been overwhelmingly successful in the setting of renal cell carcinoma (RCC). Unfortunately, another “negative” phase III trial showed that the addition of pazopanib (Votrient) to surgery did not improve cure rates for patients with RCC. Additional data was presented utilizing either clinical or genomic biomarkers that may assist physicians in choosing patients that might benefit from the addition of the oral drugs following surgery. We continue to await the results of additional completed studies and some currently enrolling studies utilizing immunotherapy before/after surgery.

2017 Genitourinary Cancers Symposium Day 3

gu_symposium_2017_img_3054 The third day of the 2017 Genitourinary Cancers Symposium started with a Best of Journals session on renal cell carcinoma (the most common form of kidney cancer) and the early poster sessions focused on renal cell, testicular, penile, and urethral cancers.

The first major morning session was focused on “novel targets and controversies in advanced testicular cancer.” Experts in the field first discussed actionable targets in testicular tumors, also referred to as germ cell tumors. This session also addressed a debate regarding treatment intensification in the subset of patients with “poor prognosis” – or germ cell tumors whose blood tumor markers do not decline optimally after initial chemotherapy. This subject remains controversial, but fortunately only affects a small number of patients, as in the current treatment era, after initial chemotherapy treatment, approximately 95% of all patients diagnosed with testicular cancer will be cured.

linehan The Keynote Lecture on renal cell carcinoma was delivered by Dr. Marston Linehan from the National Cancer Institute. He discussed the current state-of-the-art treatment which is based upon decades of research largely led by him on the genetic basis of renal cell carcinoma (RCC). Several of his discoveries about the genomics and biology of RCC have led to the current wealth of drugs available to treat this disease. One such discovery was the importance of the von Hippel Lindau gene in patients with familial cancer syndromes that also affects tumor genomics in most patients with clear cell RCC. This discovery led to investigation in targeting the VEGF pathway which is the backbone of most currently approved drugs.

The session on the diagnosis and treatment of local renal cancer (confined to the kidney) started with a presentation on the role of active surveillance or watchful observation in small renal tumors, and was followed by discussions on imaging and biopsy of renal masses. A talk about the use of ablation in small renal tumors was followed by an abstract presentation on a registry of active surveillance of patients with small renal masses. In summary, experts in the field discussed strategies and data behind the options of imaging and/or biopsy followed by either close surveillance or minimally invasive treatment strategies for patients with small renal masses.

The oral abstract scientific presentation session featured a presentation that followed up on the morning theme of small renal masses, also discussing surveillance, imaging, and circulating biomarkers. The Mayo Clinic group highlighted the success of treating carefully selected healthy patients with cryoablation in an expert center. A novel computer-assisted technique appears to be useful in assessing response to therapy compared to standard radiology assessment. A collaborative group led by Drs. Pal and Choueiri presented results of a large group of patients who had assessment of circulating tumor DNA (cfDNA) with a commercial platform prior to first-line or subsequent lines of treatment for metastatic disease. Additionally, an Italian group presented an abstract on changes in tumor burden and prognostic classification when patients with metastatic RCC utilize an active surveillance strategy rather than take medications or undergo a local procedure. This is important to realize that for carefully selected patients, just because there are metastatic (spread) tumors on scans, immediate treatment is not always necessary. Sometimes these remain stable over long periods of time without treatment and this can be discussed with experienced clinicians.

Kidneys_GU Blog_FB The final session of the conference reviewed the opportunities and challenges in systemic therapy for advanced kidney (renal) cancer. Imaging techniques to optimally evaluate one’s response to targeted therapies was discussed, highlighting examples of successful treatment with very little change in tumor measurements by traditional techniques. For example, it’s possible for a tumor to appear the same size after treatment by standard measurement, but it can be 95% necrotic (dead) tissue and in this scenario, the patient feels better and may live longer. This would be classified as non-response (or stable disease). Unfortunately, for patients with larger or more invasive tumors, many patients are not cured with surgery alone despite normal scans elsewhere in the body. Dr. Karam reviewed the results of recently presented trials utilizing targeted therapy following surgery. While these are not quite ready for primetime, the medical community is currently awaiting the results of other studies well as current studies utilizing immune checkpoint inhibitors in combination with surgery. Drs. Vaishampayan and Jonasch discussed the multiple different treatment options available to physicians and patients with advanced RCC. Physicians were reminded to consider referral to a highly experienced center for high-dose interleukin (IL)-2, a treatment which offers long-term disease-free survival off therapy in a selected subset of patients with advanced kidney cancer. Current studies are ongoing to assess different drug combinations, as well as novel agents. The last presentation of the conference was led by Dr. Powles who presented a late-breaking abstract on the randomized phase II study of atezolizumab with or without bevacizumab versus sunitinib in patients with advanced previously untreated metastatic RCC. While not definitive, the results were intriguing and support the continuing phase III study assessing the use of the combination of atezolizumanb and bevacizumab. There are multiple new studies looking at combinations of drugs and we encourage patients interested in this type of treatment to look for sites that are enrolling.

Overall, the conference was a great opportunity for both academic and community physicians from all different specialties (including medical oncology, urology, radiation oncology, radiology, and pathology) to mix with and learn from each other. We look forward to participating next February in San Francisco for the 2018 Genitourinary Cancers Symposium.

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