Key clinical trials

Here are several examples of key clinical trials funded completely or in part by the Canadian Cancer Society through the NCIC Clinical Trials Group. Each one has led to important changes in how cancer is treated.

Please note: These trials are completed and are no longer taking patients.

New results from clinical trial shows letrozole benefits even more women

Further analysis of the clinical trial involving the drug letrozole (Femara) found that women with hormone-sensitive early breast cancer who began taking the drug up to five years after completing tamoxifen therapy had a 69% reduced risk of recurrence compared to women who never took letrozole after completing tamoxifen. This finding is changing how breast cancer survivors around the world are treated.

San Antonio Breast Cancer Sympoisum, December 2005

Chemotherapy after surgery improves survival for lung cancer patients

Surgery was once the only treatment option for patients with non-small cell lung cancer but these patients may now benefit from chemotherapy. A clinical trial found that chemotherapy following surgery for patients with early-stage non-small cell lung cancer increased the five-year survival rate by 15%. There was also a significant reduction in the rate of cancer recurrence among patients. The findings have had an immediate impact on how patients with non-small cell lung cancer are treated around the world. This discovery was recognized by an international group of cancer doctors as one of the world’s most important cancer breakthroughs in 2005.

New England Journal of Medicine, 2005; 352:2589-2597, Jun 23, 2005

Reducing risk of breast cancer recurrence

A clinical trial found that post-menopausal survivors of early stage breast cancer who took the drug letrozole (also called Femara) after completing an initial 5 years of tamoxifen therapy had a 43% reduced risk of cancer recurrence compared to women taking a placebo. The research is significant because more than half of women who develop recurrent breast cancer do so more than 5 years after their original diagnosis. Prior to this research, there was no treatment to reduce the risk of recurrence after 5 years of tamoxifen. Just over half of women with breast cancer are potentially eligible for this new treatment.

New England Journal of Medicine, 329(19): November 6, 2003

Relieving lung cancer symptoms?

In its advanced stages, lung cancer can cause painful symptoms, including coughing, shortness of breath and chest pain. Radiation therapy is often used as a palliative measure to help relieve these symptoms rather than as a way to treat the disease. In a recent clinical trial, researchers found that a longer, milder course of treatment worked best for patients with non-small cell lung cancer (the most common form of lung cancer). The trial found that 5 days of radiation therapy offered more symptom relief than a single, higher dose of radiation. This treatment also extended the patients? life span by almost 2 months on average. Because of this trial, most Canadian patients with advanced non-small cell lung cancer now receive 5 radiation therapy treatments.

International Journal of Radiation Oncology, Biology, Physics: 54(3); 719-28, November 1, 2002

Improving treatment for colon cancer

In some cases, giving anti-cancer drugs after colon cancer surgery can improve the cure rate by 5 to 10%. An international clinical trial proved that a combination drug therapy which included the vitamin folic acid was the most effective and beneficial approach. This specific combination of drugs is now the most widely used treatment method for patients with colon cancer.

Journal of Clinical Oncology, 17(5), 1356-63, 1999

Improving breast cancer treatment

When breast cancer spreads to the lymph nodes, doctors know malignant cells may have spread elsewhere in the body. Because of this, surgery in patients with malignant lymph nodes is usually followed by chemotherapy. In a landmark clinical trial completed in 1998, researchers discovered that, compared to standard treatment at the time, an intense drug regimen that included a high dose of a drug called pharmorubicin (also called Epirubucin) improved survival and reduced the rate of cancer recurring. The regimen is now widely used across Canada to treat women whose breast cancer might recur.

Journal of Clinical Oncology, 16(8): 2651-8, August 1998

Controlling nausea associated with chemotherapy

Researchers continue to search for more powerful anti-cancer drugs. But patients must be able to tolerate chemotherapy, which usually causes unpleasant side effects such as nausea. A series of 9 studies, conducted from 1982 to 1995, established a new treatment practice aimed at reducing the nausea and vomiting caused by cancer treatment. The trials found that the best approach combined corticosteroids with a newer class of drugs called 5HT3 antagonists. These drugs control nausea by acting on a receptor in the brain associated with this symptom.

Journal of Clinical Oncology, 15(8): 2966-2973, 1997

Helping ovarian cancer patients

In the past, the drug paclitaxel (Taxol) was administered to women with ovarian cancer over a 24-hour time period. But a clinical trial involving Canadian and European patients found that the drug was more effective and just as safe when given over a much shorter 3-hour span. A more recent clinical trial has proven that not only is this shorter drug regimen more comfortable and convenient for patients, it actually helps delay the recurrence of ovarian cancer and prolongs the life of women with this disease.

Journal of Clinical Oncology, 12(12), 2654-66, 1994.

Last modified on: 10 December 2009