I knew that cancer was bad, and that it was made up of tumors and cancerous cells. Beyond this I didn’t know very much. I immediately started looking into how it was treated. I realized that in order to understand the treatment options, I needed to know more about what lung cancer is.
Most lung cancer starts in the lining of the bronchi, although it can also start in other areas of the lung. First, there are areas of precancerous changes in the lung. These eventually develop into tumors. The tumors produce signals that cause new blood vessels to grow that in turn feed the cancerous cells. Once this lung cancer occurs the cells can break away and spread to other parts of the body. The cancerous cells are actual lung cells that no longer behave in a normal way. They divide rapidly forming tumors that clog up the lung and make it stop functioning in a normal fashion. One of the reasons why it is hard to fight lung cancer is because the cancerous cells are actual lung cells, so the bodies immune system does not recognized them as foreign entities and try to destroy them.
WHAT ARE THE TREATMENTS FOR LUNG CANCER?
Having a basic understanding of what lung cancer is helps us understand how it is treated. Lung cancer is made up of the ‘rapidly dividing’ cancerous cells, tumors, and blood vessels that feed the tumors. The main treatments for lung cancer target these different areas. Surgery is used to remove tumors. Radiation Therapy kills tumors. General Chemotherapy drugs kill rapidly dividing cells (including the cancer cells). Targeted Chemotherapy drugs more specifically target lung cancer cells.
GENERAL CHEMOTHERAPY DRUGS:
These drugs kill rapidly dividing cells. They can’t differentiate between cancer cells and other rapidly dividing cells in the body (blood cells, cells in the mouth, stomach and bowels, and hair follicles) so they attack them all. This causes many of the adverse side effects. Many of these chemo drugs fall into two main categories. The first are platinum based drugs and the second are plant based.
1. Platinum based drugs
This class of chemo drugs normally produce the highest number of anticancer responses, but
may also cause more side effects, including low blood counts, kidney problems, nausea,
vomiting, and nerve problems.
a. Cisplatin
This was the first of the platinum based chemo drugs. It is usually administered as a
‘firstline’ drug in combination with with another drug with a different mechanism.
b. Carboplatin
This drug is similar to cisplatin but with significantly less side effects.
2. Plant based drugs
This class of chemo drugs also shows a high degree of effectiveness against cancer cells, but
with less side effects as compared to platinum based drugs. Side effects may include nausea,
vomiting, tingling in the hands or toes, fever, chills, dizziness, exhaustion, others.
a. Taxol (paclitaxel) derived from the Pacific yew tree
b. Abraxane is paclitaxel bonded to albumin without the solvent cremophor, so it may have less
side effects than Taxol.
c. Taxotere (docetaxel) derived from the European yew tree
d. Navelbine (vinorelbine) derived from alkaloids extracted from the rosy periwinkle
3. Other types
a. Gemzar (gemcitabine)
This drug interferes with the growth and spread of cancer cells in the body. Its side effects
may include low blood counts, and possible problems with the liver and kidney.
TARGETED CHEMOTHERAPY DRUGS:
Targeted therapy drugs are designed to treat the cancer cells and minimize damage to normal cells. This may reduce the treatment related side effects.
1. Avastin
This drug slows or stops the growth of blood vessels that deliver blood to the cancer, effectively
starving the cancer of of the oxygen and nutrients it requires to survive and grow. It is generally
used in combination with other chemo drugs.
2. Terceva (erlotinib)
This drug inhibits the growth of cancer cells by binding to EGFR (epidermal growth factor receptor).
It is often administered as a ’secondline’ drug. It seems to be most effective in women, people of
Asian decent, those with adenocarcinoma, and non-smokers. It is taken in pill form rather than through
an IV. Side effects include rashes and diarrhea. It’s side effects are generally milder than other chemo
drugs. It’s cancer fighting ability may diminish over time.
3. RhAngiostatin
This drug inhibits the formation of new blood vessels.
COMBINATION THERAPIES:
Cancer cells can conceivably mutate to become resistant to any single drug. By using different drugs in combination it should be more difficult for a tumor to develop this resistance. Research has shown that multi-drug combination’s improve survival when compared to treatments with a single drug. So most firstline treatments use more than one drug, each with a different operating mechanism, to fight cancer. It is common for these treatments to combine a platinum chemo drug, with a second newer chemo drug, and possibly even a third targeted chemo drug, to give the patient the strongest possible treatment.
POTENTIAL TREATMENTS FOR MELISSA:There are all kinds of chemotherapy drugs that can be used individually or in combination with others. What follows is a partial list of potential treatment options that have shown success. This list is intended to allow us to ask specific questions to the oncologist about Melissa’s treatment. We want to know what treatment is being recommended, why it is being recommended, and if it is not working, what will be tried next. We need to understand the potential effectiveness of each treatment option and compare that to it’s potential side effects.
1. Carboplatin / Taxol / Avastin
(proposed by Dr. Roberts)
2. Carboplatin / Taxol / Gemzar
3. Carboplatin / Taxol / RhAngiostatin
4. Carboplatin / Alimta / Avastin
(study proposed by Dr. Roberts)
5. Carboplatin / Gemzar
6. Taxotere / Gemzar
7. Tarceva
(proposed during meeting with TGEN)
Written by Melissa's friend, Steve