These Popular Cancer Treatments Have the Most Dangerous Side Effects

It seems like every day researchers are finding a new and improved way to combat cancer. Even so, there were still over a million new cases of cancer in 2016 alone, says the National Cancer Institute, with over half a million people killed by the disease. It’s one of the leading causes of death worldwide, with these numbers steadily on the rise.

While there are several life-saving treatments available for those who develop cancer, there are still the side effects to consider. Let’s take a quick look at how types of treatments can severely complicate your health, including cancer vaccines (No. 7).

1. Radiation therapy can give you skin lesions

Doctor posing in doctors office

Radiation therapy patients often experience serious side effects. | Jovanmandic/iStock/Getty Images

This type of treatment can be harsh on your body, as it works to totally destroy cancer cells, explains the American Society of Clinical Oncology. Radiation therapy doesn’t just target the harmful cells — it also kills the healthy ones. Though it’s more precise now than it’s ever been, you can still develop skin blisters, rashes, fatigue, and specific issues related to the treatment area. There’s also a slim chance the treatment can cause you to develop a second cancer.

Next: Chemotherapy can ruin these vital body parts.

2. Chemotherapy can ruin your reproductive organs

An IV drip seen in front of LED lights.

Chemotherapy is among the most popular cancer treatments. | Zlikovec/iStock/Getty Images

You’ve definitely heard of this common treatment before. The American Cancer Society explains chemotherapy involves fast-acting drugs that kill cancer cells — but like radiation, healthy cells also take a hit. The chemo most often harms cells in your bone marrow, hair follicles, digestive tract, mouth, and reproductive system, but everyone reacts differently. Nerve pain, issues with fertility, and infections are all common side effects.

And if you or a loved one takes chemo, you’ll definitely want to be careful of other medications. Even over-the-counter drugs and herbal supplements can have life-threatening interactions.

Next: Surgery may not seem as harsh, but …

3. Surgery can cause a loss of function in other organs

Close-up of surgeons hands holding surgical scissors and passing surgical equipment, motion blur background.

Surgery definitely has its own risks. | Xmee/iStock/Getty Images

If cancer runs in your family, you may opt to remove certain tissue or an organ before the disease has the chance to develop. Surgery is also helpful for those who have cancer localized in one tumor, Mayo Clinic says. While it may not seem as harsh as chemo or radiation, it can still come with a wealth of risks, like infection near the surgery site or loss of function in another organ that wasn’t removed. There are also bleeding and an increased chance of blood clots to consider.

Next: This can give you horrible flu-like symptoms.

4. Immunotherapy can give you horrible flu-like symptoms

Young depressed cancer patient standing in front of hospital window.

Immunotherapy might lead to other illnesses. | Prudkov/iStock/Getty Images

Not all cancer treatments involve wiping out the cells — immunotherapy actually works by boosting your immune system, the National Cancer Institute explains. But even boosting your body’s natural ability to fight disease can have consequences. Flu-like symptoms are common, and they can involve nausea, trouble breathing, and dangerous blood pressure changes. You can also expect heart palpitations and swelling from fluid retention.

Next: Here’s what can cause new cancer to develop.

5. Hormone therapy can cause new cancer to develop

Doctor talking to a patient.

Hormone therapy is a treatment with many serious side effects. | Minerva Studio/iStock/Getty Images

Women with breast cancer or men with prostate cancer are likely candidates for this treatment, as hormones in the blood affect these cancer types. It’s often used after surgery or to treat returning cancer, the American Cancer Society says. Unfortunately, hormone therapy can actually increase the chances of developing uterine cancer. There’s also an increased risk of blood clots and heart attack.

Next: A stem cell transplant can lead to this life-threatening issue.

6. A stem cell transplant can cause life-threatening infection

A stem cell shown in pink.

Stem cell research has long been a controversial treatment. | iLexx/iStock/Getty Images

Stem cell transplants are typically used to treat blood cancers. After chemotherapy or radiation, you can have healthy stem cells injected into your blood, which then work to produce normal blood cells days to weeks later. ASCO says there are a lot of side effects to consider, however. Transplants raise your risk of infection considerably, especially when performed after chemotherapy. Infertility, lung or bone damage, thyroid problems, and early menopause can also occur.

Next: A look at cancer vaccines

7. Cancer vaccines can cause breathing difficulties

Nurse fills syringe from injection vial.

Are cancer vaccines too dangerous to consider? | Khuntapol/iStock/Getty Images

Thanks to treatments like the HPV and hepatitis-B vaccines, certain types of cancer are preventable. And other types of vaccines are available to boost immunity and fight existing cancer. They do have some undesirable side effects though, according to the National Cancer Institute. These include flu-like symptoms, low blood pressure, and occasional breathing difficulties. A small number of people developed certain autoimmune diseases following the vaccine, but the correlation hasn’t been proven.