A friend of mine who had cancer a couple of years ago just got shingles. It piqued my interest into whether there was a link between cancer and shingles, as both conditions are associated with reduced immune function, and immune function may be further affected by cancer treatments.
I actually found a large study published just in June this year that looks at this very topic – Herpes zoster risk after 21 specific cancers. Other smaller studies had suggested such an association and this latest study looked specifically at different types of cancer, the age of the patient, and the time after diagnosis of cancer.
What is Herpes zoster/shingles?
Shingles occur when the varicella zoster virus (a herpes virus) is activated out of its usual dormant stage in the body during periods of reduced immunity. Varicella zoster is the same virus that causes chickenpox. After you recover from chickenpox, the virus can enter your nervous system and lie dormant for years, producing no symptoms. But if your immune function is reduced, it may reactivate and travel along nerve pathways to your skin — producing shingles.
Shingles appear most frequently as a rash on one side of the body. It can last for several weeks and often is very painful. The pain may start as a tingling and progress to burning and stinging.
In a small population of shingles patients, the pain persists for longer than 1-3 months after the rash has resolved. This is known as postherpetic neuralgia. These patients often report a constant burning, with even the slightest pressure from clothing or bedding or wind causing pain. These symptoms tend to abate over time, generally by 6 months post rash.
Immunosuppression and cancer
Cancer patients can experience reduced immune function or immunosuppression resulting from chemotherapy, psychological stress, or the physical trauma of surgery or radiotherapy.
Could this immunosuppression be a trigger that reactivates the Herpes zoster virus, thus increasing the risk of shingles in cancer patients? Let’s see what the study published just a couple of months ago found.
Shingles risk after cancer
The hematological cancers such as myeloma, lymphoma and leukemias and CNS cancer seem to be associated with a very large increased risk of shingles. This suggests that particularly in this population, it may be worth considering a zoster vaccination.
Which comes first? Chicken or the egg?
One of the things that surprised me from this study was the number of years after a cancer diagnosis that shingles risk continued to increase – up to 3 years after cancer diagnosis! This suggests that the weakened immune system is persisting all this time. But why doesn’t shingles occur earlier, for example just after or during chemotherapy when immunity is at its lowest? More research is needed to figure this out.
While it is unclear from these data whether both cancer and shingles occur because of a general underlying immune weakness or whether the cancer and its treatment cause an immune issue which then leads to shingles, the timing factor may help. This time line suggests that it is more likely that cancer and/or its treatment may cause the immune issue which leads to zoster. If it was a generalized immune suppression, it would be less likely to have a specific time peak and end.
What can we do?
As mentioned above, for those at high risk (e.g., blood based cancers), it may be advisable to vaccinate against herpes zoster. Being aware of increased risk may also prompt early anti-viral therapy if an outbreak occurs.
Generally, little attention is paid to rebuilding the immune system after cancer and its treatment. Yet a robust immune system is important to prevent infections like shingles, and to reduce the risk of cancer recurrence.
There are many natural approaches we can use to support the immune system through nutrition and lifestyle. These include:
- ensuring adequacy of those vitamins and minerals associated with the immune system such as vitamins A, and D, and selenium,
- looking at stress management,
- supporting the gut microbiota with probiotics, prebiotics and fermented/high fiber foods
- using specific immune and anti-viral supplements may also help such as colostrum, lactoferrin, beta-glucans, mushrooms, humic acid
- reducing toxins and allergens,
Immune system strengthening should be part of all after-cancer programs. Talk to your health care practitioner to see what you can do to enhance your immune system.