Chemotherapy

Normally, cells grow and die naturally in a controlled way. However, cancer cells grow continuously without forming a mass (tumor). A benign mass does not usually spread (metastasize) and does not pose a threat. On the other hand, malignant cancer cells can metastasize and cause new tumors to grow throughout the body.

Chemotherapy is the general term for any cancer treatment involving the use of chemical agents to stop cancer cells from multiplying. A chemotherapy regimen (a treatment plan and schedule) usually includes specific drugs designed to kill cancer cells. These drugs may be administered through a vein (intravenously), injected into a body cavity (such as the pleural space) through a shunt or tube, or delivered orally in the form of a pill.

Because chemotherapy agents cannot distinguish between cancer cells and healthy cells, it destroys not only the fast-growing cancer cells but also other fast-growing cells in your body, including hair and blood cells. Additionally, vital organs such as the brain, kidneys, lungs, and liver may also be subject to the lethal components of chemotherapy, so it is important for your doctor to continuously monitor your body’s response to the treatment dosage. Doctors will often perform several tests before administering chemotherapy to ensure that patients are healthy enough to undergo the selected regimen.

Malignant mesothelioma has “slow-growing” cancer cells, called epithelial type, and “fast-growing” cancer cells, called sarcomatoid type. The biphasic cell type of mesothelioma has mixed characteristics of the epithelial and sarcomatoid type. As a result, different types of chemotherapy drugs target the growth patterns of these two types of mesothelioma.

Each chemotherapy drug works differently and are effective at a specific time in the life cycle of the cells it targets. Patients may get treatment every day, every week, or every month. Sometimes patients may have breaks between treatments so that their bodies have a chance to build new healthy cells. Your doctor will determine the chemotherapy drug that is right for you.

Is Chemotherapy Right For Me?

Every patient responds differently to chemotherapy for reasons not completely known. Sometimes mesothelioma patients may develop a resistance to a chemotherapy agent. Other times, if a tumor has already developed to a large extent, chemotherapy may not be able to sufficiently treat the tumor. For these reasons, mesothelioma patients often undergo several treatment options to combat their cancer, including surgery which can physically reduce tumor size and enables chemotherapy to be more effective. Patients should get second opinions from surgeons before undergoing chemotherapy as a first line of treatment.

When chemotherapy is used, it is often administered as a combination of two or more agents (protocols). Cancer cells use various pathways in order to multiply (replicate). A single agent can only impede one specific pathway that a cancer cell uses to replicate. This allows some cancer cells using different pathways to continue multiplying unimpeded. Combination treatment such as Alimta with Cisplatin work together to impede more cancer cells from multiplying.

Chemotherapy protocols have changed and continue to change quickly. Multimodality treatment employing surgery, with Gemcitabine (Gemzar) Cisplatinum, Carboplatinum and other chemotherapies are now being adapted to use monoclonal antibodies like Iressa and Tarceva as well as anti-angiogenesis drugs like bevacizumab and endostatin as well as new targeted drugs like deacetylase inhibitor SAHA, to attack the tumor from multiple directions at once. Drugs like Interferon, Thalidomide and Cox2 inhibitors like Celebrex are being tried in various combinations to boost the effectiveness of chemotherapies.

Side Effects

During chemotherapy patients may have no side effects or just a few. There are two broad categories of chemotherapy side effects. The first and most familiar category consists of side effects that you are aware of if they occur (often called "patient-felt toxicities"). Some common examples are fatigue, nausea, vomiting, pain, and hair loss.

There is another group of side effects, such as changes in your blood cells that you may not be aware of if they occur (often called "paper toxicities"). This second category of side effects will be monitored through laboratory tests and managed by your physician. The kind of side effects a patient may have depends on the type and dose of chemotherapy. Both types of side effects could be serious if not treated.

Though a few side effects can be permanent, many are temporary. Healthy cells usually recover after chemotherapy, so most side effects gradually go away after treatment is stopped.

ALIMTA

Treatment options for non-small cell lung cancer and mesothelioma differ depending upon type of cancer, stage, size, and location of the tumor. ALIMTA as a single-agent is indicated for the treatment of patients with locally advanced or metastatic non-small cell lung cancer after prior chemotherapy.

ALIMTA, when given with Cisplatin, is the first and only chemotherapy drug to be approved by the Food and Drug Administration (FDA) for the treatment of patients with malignant pleural mesothelioma (MPM) when surgery is not an option. In the clinical studies for MPM, patients also received Cisplatin (a platinum agent), another widely used chemotherapy drug.

Information on Treatment with Alimta

Treatment Cycles with Mesothelioma

The arrival of Alimta, the first drug that showed a significant response in mesothelioma as a single agent is now being tested in clinical trials looking at combination therapies.

Ifosfamide

The ifosfamide chemotherapy drug, Ifex, has been used in to treat such cancers such as testicular cancers, sarcomas, lung cancer, and bladder cancer. Recently, it has shown promise in treating sarcomatoid mesothelioma, as well. Ifosfamide is a cell-cycle non-specific alkylating agent that inhibits the cellular division process of tumor cells, causing them to die. Ifosfamide may be able to better target sarcomatoid mesothelioma versus the FDA approved Alimta and Cisplatin combination that may be better geared towards epithelial mesothelioma.  Patients should discuss ifosfamide chemotherapy options with their treating physicians.

Treatment Info: Distributed by Bristol-Myers Squibb Company, Ifex is used in combination with a prophylactic agent called mesna to combat potential bladder damage.  Over a thirty minute time period, ifosfamide is given intravenously at a dose of 1.2 g/m² for five days. Treatment is given in three-week cycles. Ifosfamide may also be administered with doxorubicin, cisplatin, or other chemotherapy agents.  Side effects may include hair loss, nausea, poor appetite, and blood in the urine (hemorrhagic cystitis). Less common side effects are central neural toxicity, such as sleepiness, confusion, or hallucinations; and blood and fertility problems.

Cisplatin

Cisplatin is a chemotherapy drug distributed by Bristol-Myers Squibb as the brand name Platinol-AQ. It has been used to treat several types of cancers, including non-small lung cancer, and is one of the common choices for the chemotherapy treatment of malignant pleural mesothelioma. The drug is a cell cycle non-specific alkylating agent that attacks the DNA of tumor cells and inhibits the growth process, causing them to die.

Treatment Info: As a single agent, or in combination with other chemotherapy drugs, cisplatin is administered intravenously every three or four weeks. Dosage is determined on a case by case basis and can range from 20 mg/m2 per cycle to 100 mg/m2 per cycle usually calculated by bodily surface area.  Common side effects are nausea and kidney problems. More rarely, this drug may also damage hearing or cause allergic-type reactions.

Carboplatin

The chemotherapy drug, carboplatin (brand name Paraplatin) is distributed by Bristol-Myers Squibb. It has primarily been used to treat ovarian cancer but is used for other types of cancers as well. For mesothelioma patients who do not tolerate Cisplatin chemotherapy well, carboplatin may be substituted. Associated with lower toxicity levels, carboplatin is a metal salt alklating agent that damages tumor cell DNA and causes them to die.

Treatment Info: As a single agent, this drug may be administered intravenously at a dosage of 360 mg/m² on Day One of a four week cycle. Common side effects may include nausea, hair loss, taste changes, and weakness. Less commonly, patients may experience abdominal pain, diarrhea, mouth sores, numbness in the extremities, dizziness or confusion, kidney problems, hearing loss, or cardiovascular problems.