Happy February. Hope you are seeing the early signs of spring in the longer daylight hours already.
Earlier this month I had the pleasure of attending GU ASCO conference as a kidney cancer patient advocate. (ASCO = American Society of Clinical Oncology; GU = Genitourinary). This conference focuses specifically on cancers of the prostate, testes, bladder, and kidney. With this update, I hope to summarize some of the key highlights for members of Kidney Cancer Canada. As always, if you have questions, please post a question and I’ll do my best to look things up. Full details and abstracts are also available on the ASCO website on the ASCO website here.
Genetic Screening for Kidney Cancer
Dr. Brian Schuch of the National Cancer Institute (NIH) presented his paper on “Defining Early-Onset Kidney Cancer: Implications for Genetics Testing). Key notes:
- While it is commonly thought that hereditary kidney cancer makes up only 3-4% of rcc cases, that number may be as high as 5-8%
- Diagnosis of a hereditary kidney cancer is not only important to the individual, but to all family members. Known management strategies can be applied early for siblings, offspring.
- Difficulty with recognition of hereditary rcc often stems from physicians’ unfamiliarity with the rare syndromes (e.g., what is and isn’t relevant in family and personal health history)
So, who should be screened for hereditary kidney cancer?
The NCI (Urologic Oncology Branch) studied 608 patients with a hereditary form of kidney cancer. The average age of onset was in the range of 37-39 years (much younger than non-hereditary rcc which tends to occur in the later decades of life).
According to the ASCO 2003 statement regarding genetic testing, testing should be done when there is a 10% likelihood of positive result. Using this guideline, the 10% likelihood of finding a hereditary kidney cancer occurs when the diagnosis of rcc is made at less than or equal to 46 years of age.
What does this mean to you?
If you were diagnosed at age 46 or younger (and if you have any other reason to believe you may have hereditary kidney cancer such as bilateral tumours (both kidneys), or non-clear cell rcc), you should ask your oncologist about genetic screening. You will need to be referred to a genetics counsellor and will need to understand all of the insurance implications, not just for yourself, but for your children as well.
Note: The Kidney Cancer Research Network of Canada (KCRNC) — with support from KCC — is developing specific guidelines and hereditary screening protocols for Canadian patients.
Surveillance as a Strategy for Small Renal Masses
You may have seen some media news about these findings recently. In the U.S., approximately 2/3 of kidney tumours are found at less than 4 cm. Dr. William Huang discussed how surgical intervention for many of these tumours may be unncessary and that instead, surveillance may be a reasonable option. For patients older than 66, surveillance vs. surgery shows a survival advantage, perhaps because with surveillance, patients have a 49% reduced risk of a cardiovascular event. (With reduced kidney function, especially after a Radical Nephrectomy, older patients face increased risk of cardiovascular issues.)
Dr. John Core presented that, in the elderly population, two considerations should be surveillance or partial nephrectomy (noting a concern that the partial nephrectomy is not used enough).
Treatment Updates for Advanced Kidney Cancer
For advanced patients, we have three unmet needs: to improve patient outcomes, to reduce off-target toxicity, and to develop a biologic rationale for patient response (biomarkers).
- In some cases, observation as an initial strategy is perfectly valid. A small percentage of tumours will regress on their own or grow very slowly over time.
- Adequate dosing of any chosen drug is critical, whether that drug be sunitinib, pazopanib, axitinib. “Pick a drug and use it well”. There is renewed interest in alternative scheduling (for example, a schedule of sunitinib of 2 weeks on, 1 week off has significantly less Grade 3 toxicity, therefore patients may be able to stay at a higher dose and stay on longer.
- Aggressive toxicity management (expertise in managing side effects) helps to maintain an adequate dose.
- Rising stars in the pipeline for kidney cancer include: tivozanib, dovitinib, nivolumab, and cabozantinib.
Specific to Clinical Trials:
- Newer trugs such as nivolumab (BMS) require a different way of thinking about disease progression. Dr. Brian Rini reported that tumours may appear to swell (from lymphocyte invasion) and then shrink over a longer period of time (e.g, 10-20 weeks). Means that patients on trials with these agents will need to be managed differently. Trials have been designed to allow patients to continue beyond “apparent progression” versus strict RECIST criteria with measurements at 8 week intervals.
- Cabozantinib (XL 184) has shown an impressive 28% response rate in patients treated with up to 4 prior treatments. Trials are ongoing (currently in U.S. only).
- Tivozanib is currently before the FDA in the U.S. (Not yet clear whether the manufacturer will file with Health Canada for approval here).
- Dovitinib (aka TKI258) trials are complete. We are hopeful to see this trial report later this year and to see access in Canada in the 3rd line setting.
One thing is very clear. Without clinical trials, we would have no treatments whatsoever. Each and every researcher makes a point of thanking the patients and families who enrolled in these studies.
Thanks to all of the patients and their families for participating in the research that leads us forward. When you have a treatment decision to make, please ask your oncologist whether there are any clinical trials that you might be able to participate in. Thank you.
Has this Blog report been helpful? If you can support the work we do for kidney cancer patients in Canada, please consider making a personal donation to our charity. We are the only Canadian charity whose mission is to focus exclusively on kidney cancer. To make a donation, please click here.