Here are answers to the internet's most frequently googled questions about cancer, focusing on treatment.

How is cancer treated?

The three most common types of cancer treatment are surgery, radiation, and chemotherapy. However, research has made several more available in recent years. Here are all the major forms:

Surgery

Surgery works best on solid cancers that haven't spread. It's used to remove an entire tumor, parts of a tumor, or even just to remove tumors that are causing pain. Surgeons usually try to be as minimally invasive as possible to minimize the damage that could be done to the area surrounding a cancerous tumor. There are several specialized types of surgery beyond traditional methods of removal with a scalpel:

• Cryosurgery: Extreme cold is used to destroy abnormal tissue. This kind of surgery is commonly used to treat early-stage skin cancer, retinoblastoma, and precancerous growths on the skin and cervix.
• Lasers: Laser beams are used to focus on tiny areas and very precisely remove tumors or other growths. This is commonly used to treat basal cell carcinoma, cervical, vaginal, esophageal, and non-small cell lung cancer.
• Hyperthermia: Extreme heat is used to kill cancer cells or make them more sensitive to other treatments. This kind of surgery is still being studied and isn’t commonly used.
• Photodynamic therapy: Drugs are taken that react to certain kinds of light, which is then shone on the tumor so the drugs become active and kill the cells. This is commonly used for skin cancer and non-small cell lung cancer.

Radiation therapy

This technique uses high doses of radiation in an attempt to slow the growth of cancer cells--or even kill them--by destroying their DNA. This takes several treatments and doesn't begin working immediately, but cancer cells continue dying after treatment ends--for weeks or even months afterward. Radiation is often combined with surgery and can be done before, after, or even during a surgical procedure. There are two types of radiation:

• External beam: A large machine moves around the patient treating a specific area with radiation.
• Internal radiation: A solid or liquid radiation source is put inside a patient's body to treat cancer from within. This is common with head and neck cancers, breast, cervix, prostate, eye, and thyroid cancers.

Chemotherapy

Again, this method of treatment is used to slow or stop the growth of cancer. Some people might only have chemotherapy, but it's commonly combined with other forms of treatment like surgery and radiation. It can be done orally, through injection or IV, via a topical cream and several other ways--but IV is probably most common. Lots of different drugs are used for chemotherapy, depending on the type of cancer a patient has and other medical history information.

Immunotherapy

This form of cancer treatment is very new, and very hopeful for many cancer researchers. Immunotherapy isn't as common as the previous three treatments, and many drugs in this family of treatment are still in clinical trials or under early research.

The immune system normally helps the body fight disease, but cancer is very good at evading it. Immunotherapy aims to increase the system’s ability to attack cancer cells. There are several types of immunotherapy:

• Checkpoint inhibitors: Drugs are used to decrease cancer’s ability to evade the immune system.
• Adoptive cell transfer: Immune cells are taken from a patient’s tumor and the most effective are grown in a lab for a few weeks. The cells are then reinjected into the patient’s bloodstream.
• CAR T-cell therapy is a type of adoptive cell transfer. It has advanced the furthest of all the methods of immunotherapy. The first two treatments were FDA approved in 2017 (one for a type of children’s leukemia and another for adult lymphoma). These treatments have had very good results in clinical trials and drawn a lot of attention in the media.
• Monoclonal antibodies: Immune system proteins are made in a lab and designed specifically to attach to cancer cells. Some “mark” them so the immune system can better attack the cells. Others slow or kill tumors.
• Treatment vaccines: Unlike vaccines that prevent diseases, these treat cancer that’s already present by helping the immune system target cancer cells

Targeted therapy

This type of treatment specifically targets the things that make cancer fast growing and spreading. Often, biopsy is used to determine whether these drugs will be helpful. They could have several functions:

• Help the immune system
• Stop cancer cells from growing, or kill them
• Prevent cancer cells from forming blood vessels to feed themselves, or otherwise starve them
• Take toxins to cancer cells

Hormone therapy

Hormone therapy works by either preventing the body from creating hormones or by stopping hormones already inside the body from working. The aim is to slow or stop the growth of cancer, make tumors smaller before surgery, or make cancer less likely to return after surgery. It can also ease or prevent symptoms for men with prostate cancer.

This treatment is administered by orally taking pills, injections, or by completely removing hormone-producing organs like the ovaries or testicles.

Stem cell transplant

This usually isn't used to directly treat cancer, but to help patients recover from other forms of treatment that do. An IV is used to inject healthy blood-forming cells in an effort to replace those killed as a side-effect of other cancer treatments. The stem cells could come from the patient or a donor.

However, in the case of multiple myeloma and some types of leukemia, stem cell transplants can be used to directly fight cancer.

This form of treatment is commonly used with patients who have leukemia, lymphoma, neuroblastoma, and multiple myeloma.

Can cancer spread while on chemotherapy?

Yes. If chemotherapy isn’t working, this could happen. This could be the case for several reasons.

What is the life expectancy of cancer without treatment?

There are almost infinite possible scenarios here. What kind of cancer? Has it spread or was it caught early? What kind of medical history does the patient have? We’ll focus on three different examples.

In 2005, a Swedish study found that women who refused treatment for breast cancer were 2.1 times more likely to die as a result of their cancer than those who were treated with surgery (usually the most important part of breast cancer treatment).

Another study of Canadian breast cancer patients in 2012 found that women who received standard treatment had an 81.9% 5-year survival rate while those who refused standard treatment had a 46.2% 5-year survival rate. A 5-year survival rate is a number researchers use to quantify survivability of cancer. It's the percentage of patients who are alive 5 years after the date they were diagnosed or started treatment.

Lung cancer is one of the most deadly forms of cancer. For most early stage lung cancers, the best treatment is surgery. 5-year survival for such patients is in the 50-70% range, and average survival following surgery is approximately 46.2 months (or 3.85 years). Some patients do not qualify for surgery due to other factors in their medical history. They are typically treated with radiation and have a 5-year survival rate between 13 and 23%. Researchers found an average survival time after treatment to be 19.9 months (or 1.66 years). Some patients, however, are ineligible for either treatment and sometimes go completely untreated. A 2005 study in the U.S. found that these patients survive, on average, for about 11.9 months (or approximately one year) after diagnosis.

However, part of the reason lung cancer is so deadly is because it’s usually not found in the early stages of the disease when it’s more treatable and thus more survivable. Overall, lung cancer has a 5-year survival rate of about 16% and is considered a terminal illness. A 2012 U.S. study found that untreated lung cancer patients, without regard to stage, live for 7.15 months on average.

Having said all this, these rates are based on many people to give a general idea about what cancer usually looks like, but some people are unique. They may live shorter or longer than any of these figures. For example, someone who was in perfect health before they developed cancer could potentially live longer than these numbers would suggest. The opposite could also be true. What’s clear is that cancer patients should be consulting closely with their doctors about treatment, and that the treatments we use today do make a difference.

 Sources

Cancer survival statistics: What they can and can't do. (2018, February 21). Retrieved from https://www.mayoclinic.org/diseases-conditions/cancer/in-depth/cancer/art-20044517 

CAR T Cells: Engineering Immune Cells to Treat Cancer. (2017, December 14). Retrieved from https://www.cancer.gov/about-cancer/treatment/research/car-t-cells 

Chemotherapy. (2015, April 29). Retrieved from https://www.cancer.gov/about-cancer/treatment/types/chemotherapy 

Hormone Therapy. (2015, April 29). Retrieved from https://www.cancer.gov/about-cancer/treatment/types/hormone-therapy 

Immunotherapy. (2018, May 24). Retrieved from https://www.cancer.gov/about-cancer/treatment/types/immunotherapy 

Joseph, K., Vrouwe, S., Kamruzzaman, A., Balbaid, A., Fenton, D., Berendt, R., . . . Tai, P. (2012). Outcome analysis of breast cancer patients who declined evidence-based treatment. World Journal of Surgical Oncology,10(1), 118. doi:10.1186/1477-7819-10-118

Precision Medicine. (2017, October 3). Retrieved from https://www.cancer.gov/about-cancer/treatment/types/precision-medicine 

Radiation Therapy. (2017, July 19). Retrieved from https://www.cancer.gov/about-cancer/treatment/types/radiation-therapy 

Stem Cell Transplant. (2015, April 29). Retrieved from https://www.cancer.gov/about-cancer/treatment/types/stem-cell-transplant 

Surgery. (2015, April 29). Retrieved from https://www.cancer.gov/about-cancer/treatment/types/surgery 

Survival in early-stage non-small cell lung cancer. (2005). International Journal of Cancer Research and Treatment,25(5), 3517-3520. doi:25: 3517-3520

Targeted Therapy. (2014, August 15). Retrieved from https://www.cancer.gov/about-cancer/treatment/types/targeted-therapies 

Verkooijen, H. M. (2005). Patients’ Refusal of Surgery Strongly Impairs Breast Cancer Survival. Annals of Surgery. doi:10.1097/01.sla.0000171305.31703.84

Wao, H., Mhaskar, R., Kumar, A., Miladinovic, B., & Djulbegovic, B. (2013). Survival of patients with non-small cell lung cancer without treatment: A systematic review and meta-analysis. Systematic Reviews,2(1). doi:10.1186/2046-4053-2-10