TLDR- Ask your doctor to test for DPD deficiency prior to beginning chemotherapy.
As Rebekah entered her third week of chemo pills and radiation, things took a hard left turn. She had moved into her closet to be close to the bathroom and became nearly vegetative. I would come over daily after work with food, trying all kinds of recipes from the Cancer-Fighting Kitchen cookbook that she might be able to tolerate, but not only could she not eat anything, she was hardly awake. When I visited her in the closet, she would barely register my presence, stuck in a halfway state between consciousness and unconsciousness. We were all naturally very worried, but since we had no frame of reference and things seemed okay at doctors’ visits, we thought, well, this is the reality of cancer.
However, when she reached the point where she said she wanted to stop treatment and asked us to call hospice when she was ready, something was clearly very, very wrong. I had gone with her to her doctor appointment earlier that week and voiced my concern that something wasn’t right. But the numbers all looked fine and cancer is brutal, so they agreed to give her a few more days’ rest but insisted she needed to push through and finish treatment. Less than 48 hours later, I was taking her to the ER. She was admitted to the hospital and ended up staying there for the remainder of the month, our version of summer vacation at the Rex-Carlton, as we jokingly call it.
In the meantime, despite the break from chemo, she was not getting better. While hospitalized, they ran every test imaginable and finally got an answer—she had DPD deficiency.
What is DPD Deficiency?
After spending a few days in the hospital, Rebekah’s oncologist, Dr. B., made a special visit after hours to inform her that they had identified she had DPD deficiency. The nurses on the floor gathered around Rebekah’s room to witness the unusual occurrence of an oncologist visiting a patient after hours. None of them were familiar with DPD deficiency. Dr. B. mentioned that Rebekah was only the second patient he had encountered with this condition.
In response, my family delved into researching DPD deficiency to gain a deeper understanding. We discovered its rarity, affecting less than 5% of the population (which reinforced our belief in Rebekah’s uniqueness). Despite its low prevalence, DPD deficiency is profoundly serious. Due to its rarity, it is not standard procedure in the US to test for this deficiency before beginning chemotherapy.
DPD (dihydropyrimidine dehydrogenase) deficiency is a condition where the body lacks enough of the enzyme needed to break down certain chemotherapy drugs, such as 5-FU (fluorouracil) and capecitabine. This deficiency can lead to severe toxicity because the drugs are not metabolized properly, causing them to build up in the body to dangerous levels. This is what was happening to Rebekah- she was experiencing severe toxicity.
This meant changing her dosage of pills, adjusting her treatment timeline, and changing the dosage for infusion chemo. Finally, with an answer, we could move forward. But it left us feeling uncertain. How do you know when you don’t feel well because of treatment, and how do you know when it is dangerous? She had the most amazing team of doctors, PAs, and nurses, but even still, it’s really important to ask questions, speak up, and advocate for yourself when you think something isn’t right. Healthcare professionals will do all they can, but knowing your body is also important. And it’s really important to have people around you who can help advocate when you can’t do it for yourself.
Hindsight is 20/20. If we knew then what we know now, Rebekah could have advocated for herself more, and her caretakers could have advocated for her.