Many of us are aware of the risk of tumor lysis syndrome (TLS) when we commence treatment, particularly with venetoclax and that the purpose of the venetoclax ramp-up, is to reduce the risk of TLS occurring. TLS can also occur with other CLL treatments, especially when they are fast acting, rapidly killing CLL cells, such as can occur with obinutuzumab and rituximab. Having poor renal function and/or a large CLL tumour burden; such as an enlarged spleen, large lymph nodes, and/or a high lymphocyte count, also increases your risk.
Many may not be aware that three brave CLL patients lost their lives in an early phase venetoclax clinical trial, halting that trial until the FDA was satisfied that the trial could safely continue with the ramp up which was introduced to mitigate that risk. So now have the venetoclax/Venclexta prescribing information, which includes the legacy of a TLS assessment risk. The starting pack accordingly includes the 10, 20, 50, 100, 200, 400mg dose per week ramp-up packs. From the venetoclax prescribing information venclextahcp.com/cll/dosing...
Considerations for TLS with VENCLEXTA (venetoclax tablets)
- VENCLEXTA can cause rapid reduction in tumor and thus poses a risk for tumor lysis syndrome (TLS) at initiation and during the ramp-up phase in all patients, and during reinitiation after dosage interruption (see dose modification and interruption information)
- Changes in blood chemistries consistent with TLS that require prompt management can occur as early as 6 to 8 hours following the first dose of VENCLEXTA and at each dose increase
- The risk of TLS is a continuum based on multiple factors, particularly reduced renal function (CLcr <80 mL/min) and tumor burden; splenomegaly may also increase the risk
- Consider all patient comorbidities before final determination of prophylaxis and monitoring schedule
- The risk of TLS may decrease as tumor size decreases
Further down in the venetoclax prescribing information, you'll find the Tumor Burden Assessment Tutorial
venclextahcp.com/cll/dosing...
For those interested in thorough detail about TLS and how it is treated, this is covered in this week's The Bloodline with LLS - A Podcast for Patients and Caregivers
Tumor Lysis Syndrome: What Patients Need to Know
In certain blood cancers, an urgent condition called tumor lysis syndrome (TLS) can develop. Dr. Tina Bhatnagar of the West Virginia University Cancer Institute joins us in this episode to explain why tumor lysis syndrome occurs and how it is treated. Although considered a medical emergency, Dr. Bhatnagar reviews how prevention and treatment can be successful in the treatment of TLS.
:
And what it essentially amounts to is a tumor breakdown. As cancer cells are dying off, either spontaneously or in response to chemotherapy, a number of electrolytes, including phosphate and uric acid end up in the bloodstream and can end up precipitating in the kidneys and ultimately causing a lot of organ dysfunction.
Primarily, we see it in the kidneys; but in it's most severe forms, it can cause neurologic issues like seizures or altered mental status, or it can also cause heart rhythm disturbances if left untreated. And so, it is something to be very aware of, and it has to be monitored aggressively because it's very treatable and something that can eventually lead to significant side effects and morbidity if it's left untreated.
The interview transcription is available here: thebloodline.org/TBL/wp-con...
Of note. the requirement to drink more fluid than you may be used to, prior to and throughout the venetoclax ramp-up phase is to help protect your kidneys. Just keep in mind that more is not necessarily better; drinking excessive amounts disrupts your sleep, which your body needs for repair/recovery during treatment. It's also possible to make yourself very ill if you overdose on water/fluids, when you can develop potentially fatal hyponatremia (too dilute blood sodium). mayoclinic.org/diseases-con... Again, from the venclexta dosing and administration information, with my emphasis:-
*1.5-2 L of water (~56 ounces) should be consumed every day starting at least 2 days before the first dose and throughout the ramp-up phase, especially the first day of each dose increase. Administer intravenous hydration for any patient who cannot tolerate oral hydration.
†Start allopurinol or xanthine oxidase inhibitor 2 to 3 days prior to initiation of VENCLEXTA.
‡Evaluate blood chemistries (potassium, uric acid, phosphorus, calcium, and creatinine); review in real time.
§For patients at risk of TLS, monitor blood chemistries at 6 to 8 hours and at 24 hours at each subsequent dose ramp-up.
Note that you don't need to continue with the high fluid intake after you have completed ramp-up. Also, while the dosing information doesn't specifically note this, all fluid intake, not just water should be counted in achieving the 1.5 to 2 litres. The slight diuretic effect of caffeine in tea, coffee and energy drinks, isn't considered to make any difference. Per this advice from Mayo Clinic "Water is the best liquid you can drink to stay hydrated. But caffeinated drinks can help meet your daily fluid needs." mayoclinic.org/healthy-life...
Given the importance of knowing about TLS, this is an unlocked post, so any replies can be read by people finding this post via Google, etc.
Neil