Christopher J. Pietras, MD
There are not many randomized placebo-controlled trials investigating the use of ketamine as a palliative agent in ovarian cancer, but Christopher J. Pietras, MD, said that it can be considered in certain patients with difficult-to-treat pain symptoms. This adds to the overall message that palliative care agents should be tailored depending on patients’ symptoms.
“Treating patients’ symptoms, just like treating peoples’ cancers, is very individualized,” said Pietras. “It’s very important to involve the oncologist, the primary care physician, or a specialist in palliative care or pain so that they can assess where the symptoms are coming from and why.”
In an interview during the 2018 OncLive®
State of the Science Summit™ on Ovarian Cancer, Pietras, who is the director, Palliative Care and assistant clinical professor, University of California, Los Angeles School of Medicine, discussed the elements of palliative care for patients with ovarian cancer.
OncLive: What did you discuss in your presentation on palliative care in ovarian cancer?
: I covered end-of-life discussions and their associations with the quality of medical care, as well as their effects on caregivers and family members. Secondly, I focused on difficult-to-control symptoms and the use of ketamine for those symptoms in patients with advanced cancer. Thirdly, I spoke about the importance of treating constipation, which is a common symptom. I also discussed the use of docusate sodium for patients near the end of their lives.
What are the elements of palliative care?
Palliative care is specialized interdisciplinary care that is focused on improving the quality of life (QOL) of patients and their families. Palliative care also provides support and direction in the setting of complex medical decision making.
What medications are used to manage difficult-to-control symptoms?
For severe pain, first-line agents include opioid medications, such as morphine. If those are ineffective, other types of medications are added. Different possibilities include gabapentin and tricyclic antidepressants such as nortriptyline or amitriptyline. [These agents can be used] for neuropathic-like pain that may result from a cancer that may be touching a nerve.
If those medications are ineffective at high doses, ketamine can be considered in certain populations. Although the data for ketamine do not include a large number of placebo-controlled trials, there are smaller studies suggesting that ketamine may be beneficial when used appropriately for patients with very difficult-to-control pain symptoms. These patients would already be on very high doses of opioids and non-opioid adjuvant medicines, like gabapentin.
Ketamine can significantly improve pain scores in up to half of patients, although we still need to do larger studies and prospective trials to confirm whether these data are correct or not. Part of the presentation addressed that only 3 out of 200 papers, analyzed in the only systemic review we have, met the criteria for generalizable evidence.
Based on that evidence, we have to conclude that we do not yet know whether ketamine will result in symptom improvement. Therefore, ketamine should only be used in a select group of patients who have uncontrollable pain—despite highly escalated opioids and other medications—and in patients who do not have traits that would make them more likely to have side effects. This includes patients who might feel confused and those who have anxiety, as those are the most common side effects with ketamine.