For the past half a century, chemotherapy has played a crucial role in the ongoing battle against cancer, providing doctors and oncologists with the means to fight cancer at the cellular level. But despite chemotherapy's importance as a vital medical advancement, myths and misunderstandings abound. Indeed, most of us have very little knowledge of how the process works. For some much needed clarity, we talked to Dr. Frances Shepard, a lung cancer specialist and clinical researcher, and Janice Stewart, manager of the chemo daycare transfusion unit, both of Toronto's Princess Margaret Hospital. Here they clear up the nine most prevalant chemo confusions.

1. Chemo kills cancer cells only
Chemotherapy medications are often defined as anti-cancer drugs or cancer killers, definitions that add to the confusion. The drugs that make up chemotherapy treatments are designed to inhibit rapid cellular growth by attacking cells at their core –- their DNA, or the enzymes that promote their growth. In fact, the medical community often refers to chemo as 'cytotoxic' (or cell killing) treatment. That's a far more accurate description.

The key difference between cancer cells and healthy cells is not the speed in which they regenerate, but the fact that cancer cells grow in an unregulated manner. The 'orders' from their 'headquarters' -– the DNA programmed with their job descriptions –- have become muddled. Chemotherapy drugs are designed to kill cells that grow in a specific manner, but they cannot always attack cancer cells exclusively. Hence, common side effects such as hair loss, which is an indication of the drugs harming the rapidly growing cells in our hair follicles. It is important to acknowledge that chemotherapy doesn't affect cancer cells alone and to understand how the treatments work. This way, the side effects seem less arbitrary.

2. There is only one type of chemotherapy
Chemotherapy is by no means a standardized treatment. There are a variety of drug therapies on the market, and they are used for different reasons, sometimes in tandem (called a doublet) or in combination with other drugs. "Treatments are becoming more customized," says Stewart. "It is now a different process for different individuals." Two women with breast cancer may not receive the same treatment cycle, and it should be noted that chemotherapy is not a one-size-fits all treatment. Furthermore, chemo is often used before surgery (neo-adjuvant) to reduce the size and spread of the tumour, after surgery (adjuvant), to contain the spread of any cancer cells that the procedure may have missed, or alongside radiation therapy. "There is no standard chemotherapy," notes Dr. Shepard. Each patient is treated as a separate case, and is administered the treatment option best suited for them.

3. Chemo is painful
Dr. Shepard encounters many patients who are afraid of the pain they believe chemo will cause. This is one of chemotherapy's most pervasive and inaccurate myths. "The therapy is almost never at all painful," she says. Although, as we have already noted, there are side effects, chemotherapy drugs have advanced so significantly that most patients will be treated on an outpatient basis, and are rarely admitted to hospital for an overnight stay. "Twenty-five years ago, patients would stay for two or three days following a chemo cycle," explains Stewart. "The quality of people's lives while on treatment has improved dramatically." Chemo may have its drawbacks, but pain simply is not one of them.

4. Chemo causes unbearable nausea
"Patients are very, very afraid [of nausea]," notes Dr. Shepard. While nausea can be a problem for some people, it has been limited as a major side effect in the past several years. We are now at the point where illness and nausea is a rarity. New agents such as the anti-nausea drugs Zofron and Kytril are able to very effectively control the symptoms of nausea and allow patients to leave the hospital almost directly after treatment, where previously they would require several days of recovery time. Some chemo drugs are so efficient almost no nausea is experienced. Specialists also recommend that patients eat numerous small snacks throughout the day, rather than three big meals, to counter small bouts of queasiness.

5. Immunity is compromised during chemo
Dr. Shepard notes that a great number of her patients assume their immune systems are severely compromised during treatment, and that they are in great danger from a variety of infections. "From a medical point of view, there is a reduction in the white blood cell count [during treatment]," observes Dr. Shepard. This reduction, however, is not significant enough, nor does it occur for a long enough period of time, to put a patient at a greater risk of viral infections or fevers. The drugs are powerful, and the patient may feel their effects by becoming more fatigued or lethargic than usual, but there is no hard science or data suggesting that chemotherapy weakens the immune system significantly, leading to more viral infections in patients than in the general population.

6. Everybody loses their hair
Not true. "With more and more [of the new chemo drugs], this is less and less likely," says Stewart. Although we have already learned that damage of the hair follicles at the cellular level can be a side effect of the cytotoxic properties of chemo drugs, many new medications are so targeted that this most recognizable feature of cancer treatment is no longer a given. Even with a disease like lung cancer, which was once almost impossible to treat, new drugs such as Cisplatin and Vinorelbine cause very little cellular damage other than to metastasizing cancer cells.

7. I can't get pregnant during chemo
"This is a big one," Stewart says. It is a misconception that she finds necessary to address with patients at the very beginning of their treatment cycle. Many women and their partners assume that they cannot conceive during chemotherapy, and find out how wrong they are a short time into treatment. "We really stress birth control," she adds. Pregnancy can be an enormous complication during chemo, so extra vigilance is recommended. And it's not just women who think they're infertile. Chemotherapy does not necessarily kill sperm cells, so men should not forgo regular birth control methods when they are undergoing chemo.

8. Chemo makes me toxic
We have to accept the fact that chemo drugs are powerful medications, and many have toxic properties that can be harmful if not administered with great care and expertise. But they do not make patients untouchable. "Many patients think that they need to sleep in different beds from their partners, or use different washrooms," says Stewart. This is not the case. A chemo patient cannot contaminate their family or friends with toxic excretions, so there is no issue with maintaining a regular lifestyle.

9. The cure is worse than the disease
Many people are under the impression that chemotherapy will significantly reduce their quality of life for an extended period of time. Dr. Shepard contradicts this by pointing out that "the transient negative effects are worth the goal, and the side effects usually disappear shortly after treatment."

We meet more and more cancer survivors, and encounter so many more individuals who continue working and living their lives with only a few small concessions to their treatment. Chemo can take an emotional, mental and physical toll, but it is not as devastating as many patients assume. Furthermore, treatments have become so effective that, as Ms. Stewart points out, "we have turned cancer into a chronic disease rather than acute disease that kills."

Chemotherapy can be a tough slog for those who must endure it, but the myths about the treatment engender a fear that has little basis in reality. Most of the public seems to think of chemotherapy much as it was in the '50s or '60s, and are unaware of the immense changes that the process has undergone. "It is now much easier to endure," says Stewart.