A new clinical trial has started to look at the effectiveness of using erlotinib in conjunction with adjuvant chemotherapy in hopes that it will prove to be an effective treatment protocol for non-small cell lung cancer.
Erlotinib is sold under the trade name "Tarceva." It is usually used to treat non-small cell lung cancer that has metastasized and not improved with chemotherapy. It is also used to treat advanced pancreatic cancer, and trials are under way to test Erlotinib's effectiveness against other cancers.
This particular clinical trial regarding non-small cell cancer treatment entered phase 3 earlier this year.
What is lung cancer?
More than 1.2 million cases of lung cancer are diagnosed each year worldwide. Lung cancer causes one death every three seconds and is responsible for nearly 30 percent of cancer deaths in the United States.
Lung cancer is actually a group of cancers that affect the lungs and the two large airways in the lungs (the bronchi). There are two major classes of lung cancer: non-small cell, which is the most common, and small cell.
There are three major sub-types of non-small cell lung cancer (NSCLC) which have earned their names because of how they look under a microscope:
Adenocarcinoma - Approximately 40 percent of all NSCLC cases are adenocarcinoma making it the most common type of NSCLC. This cancer is usually found on the outer surface of the lungs and varies in size and rate of growth. Women and non-smokers who develop this kind of cancer usually get "bronchioloalveolar" carcinoma, which counts for 5 percent of lung cancers.
Squamous cell carcinoma - This type of cancer usually arises in one of the two airways in the lungs (the bronchi) and grows relatively slowly compared to other cancers.
Large cell carcinoma - This type of cancer can appear in any area of the lungs and is known to grow and spread rapidly.
"Approximately 55 to 65 percent of lung cancers are non-squamous NSCLC" (www.radiantlungstudy.com).
Researchers have found that NSCLC has four stages:
Stage 1 - The tumor is located in only one lung and has not spread to the lymph nodes or areas outside the lungs.
Stage 2 - The tumor is located in one lung and may involve lymph nodes on the same side of the chest.
Stage 3 - There is more extensive involvement of the lymph nodes and/or the primary tumor has spread to other areas of the chest.
Stage 4 - The tumor has spread to other sites in the body - outside the chest.
Survival Rates for NSCLC Patients
The average survival rate of patients at all stages of NSCLC over five years in the United States is 15 percent. As with most cancers, the earlier the detection, the earlier the initiation of treatment and the better the chances of survival.
If a person is found to be at Stage 1 when they are diagnosed there is a 47 percent chance of survival; Stage 2, 26 percent; Stage 3, 8 percent; and Stage 4, 2 percent.
The Risk Factors
Cigarette smoking is the leading risk factor. Combined with exposure to secondhand smoke, cigarette smoking accounts for an estimated 87 percent of lung cancer cases.
Other risk factors include:
- Exposure to arsenic, radon, benzene, asbestos, radiation therapy to the chest, or a history of tuberculosis
- Family history of lung cancer (due to shared environmental and genetic factors)
- A person with more than one risk factor is at a significantly higher risk of developing lung cancer.
Treatment for NSCLC
NSCLC is treated with four methods - surgery, radiation therapy, chemotherapy, and targeted therapies. These treatments may be used in conjunction with one another or on their own.
Erlotinib or Tarceva is a pill that is meant to be used following surgery. The current clinical trial is looking at how effective Tarceva is when used on its own and following chemotherapy in EGFR-Positive tumors.
EGFR stands for "epidermal growth factor receptors". "Many cells, including cancer cells, have receptors on their surfaces for epidermal growth factor (EGF), a protein that is normally produced by the body and that promotes the growth and multiplication of cells. When EGF attaches to epidermal growth factor receptors (EGFRs), it causes an enzyme called tyrosine kinase to become active within the cells. Tyrosine kinase triggers chemical processes that cause the cells, including cancer cells, to grow, multiply, and spread" (www.medicinenet.com).
Studies have shown that Erlotinib attaches to these EGFRs and keeps the EGFs from attaching themselves to the cancer cells. This stops cancer cells from growing and multiplying.
Erlotinib treatment is usually offered to patients who have already completed one round of chemotherapy. So far, patients who have received Erlotinib survived an average of 6.7 months compared to 4.7 months for those who received the placebo.
To find out how you can participate in the clinical trial of this drug visit www.radiantlungstudy.com for more information about study locations in Canada and the United States and to find out if you are eligible to participate.
Sources: www.radiantlungstudy.com; www.nlm.nih.gov (U.S. National Library of Medicine and the National Institutes of Health); www.cancer.gov (National Cancer Institute); www.medicine.net.com; www.tarceva.com; www.pubmed.gov (U.S. National Library of Medicine and National Institutes of Health)