Chemotherapy For Ovarian Cancer

Overview

Ovarian cancer is a type of cancer that is found in the ovaries. It is an abnormal overgrowth of cancerous cells that rapidly grow and start to damage healthy tissue. This type of cancer affects people assigned female at birth (AFAB) and it can be hard to detect because symptoms develop at a later stage.

Both surgery and chemotherapy are the mainstays of treating ovarian cancer and your doctor will help you decide which course of treatment is best suited for you. Chemotherapy consists of drugs, which can destroy cancer cells and they are used at various stages of treatment. 

It can be quite distressing to learn that you or someone you know has been diagnosed with ovarian cancer. However, there are multiple different treatment options available for this diagnosis and this article will aim to equip you with all the information relevant to this type of cancer. 

Understanding Ovarian Cancer 

Ovaries are two, small glands which are found in AFAB individuals and they are located on either side of your uterus, in your lower abdomen. The  eggs (ovum) in AFAB individuals are made and stored in the ovaries, and these ovarian glands also produce the AFAB sex hormones which play an important role in maintaining the menstrual cycle and supporting pregnancy. Each menstrual cycle, one ovary will release an ovum, which may or may not be fertilised by a sperm to result in pregnancy. This process will continue until the person reaches menopause. 

There are three different types of ovarian cancer; epithelial ovarian cancer, stromal cell tumour and germ cell tumour. Epithelial ovarian cancers are the most common and they can quickly spread to the abdomen. They are often detected in the later stages of the disease. Stromal cell ovarian cancers are the least common and they are generally detected quite early on due to abnormal vaginal bleeding. Germ cell tumours mostly affect younger AFAB individuals and carry a slightly better prognosis.¹  

When someone is diagnosed with cancer, the cancer is staged, using diagnostic tests, according to the size of the cancer and how much it has spread in the body. Ovarian cancer is classified into four stages with the first stage indicating the cancer is localised to the ovaries. The fourth stage indicates the cancer has spread to important organs, for example, the lungs and liver. Your treatment will be decided based on what stage your cancer is at. 

Role of Chemotherapy in Ovarian Cancer Treatment 

Basics of Chemotherapy 

Chemotherapy is the administration of drugs in order to destroy cancer cells. Depending on which stage of ovarian cancer you have, chemotherapy might be used on its own, or paired with surgery. It is often given before surgery (neoadjuvant therapy) in order to shrink the growing cancer cells which can make it easier to remove. Or it might be given after surgery (adjuvant therapy) to destroy any tumour cells that might be left behind or to prevent cancer cells from returning. At times, if your ovarian cancer is caught early enough, you might not even need to receive any chemotherapy and just surgery alone may suffice. 

Chemotherapy is usually administered through your vein (intravenously) and it is given once every three weeks with a period of rest following the administration. This three week period is known as one cycle of chemotherapy. How many cycles you will need will depend on what stage your cancer is at, but usually, six cycles are conducted.²

The drugs given during chemotherapy enter your bloodstream and are circulated all over the body and can attack and destroy cancer cells anywhere in the body. A cancerous tumour is made up of rapidly dividing cells that form a mass. Drugs given during chemotherapy target and destroy these dividing cells as they multiply much quicker than normal cells, which are usually at rest.³ 

Combination Therapies

Sometimes you might be given a combination of different chemotherapy drugs. These different drugs will attack cancer cells at various stages of cell division and hence, it will increase the chances of destroying more cancer cells. 

In ovarian cancer, taxane-based and platinum-based chemotherapy drugs are used often. Platinum-based drugs will contain platinum as a core ingredient and they destroy cancer cells by hindering their division and growth. Taxane-based drugs are chemically produced and they also prevent division and growth of cancer cells. 

Chemotherapeutic Agents Used in Ovarian Cancer

The most common platinum-based drugs used in ovarian cancer are carboplatin and cisplatin. However, it has been proven that whilst both these drugs are equally effective, carboplatin shows lesser toxicity and side effects and is therefore preferred in ovarian cancer.⁴ 

Platinum-based drugs can be used in combination with a taxane-based drug for a better response. The most commonly used are paclitaxel and docetaxel and they are often used alongside carboplatin.⁵ 

In addition, there is a class of drugs known as targeted cancer drugs that specifically target the proteins that cause cancer cells to divide and multiply. These drugs are used in ovarian cancer for a more precise treatment and some examples are bevacizumab and PARP inhibitors. 

Administration and Side Effects of Chemotherapy

Methods of administration

The most commonly used method of administering chemotherapy is through a vein in your arm or hand via a cannula. At times, a central line might be needed; a central line is a thin tube that administers the drugs directly into a large vein, usually in the chest. This central line has to stay in for the entire duration of treatment which might last a few months. 

Chemotherapy can also be given through a long, narrow tube (catheter) inserted into your stomach and this is known as intraperitoneal chemotherapy. It might be considered in patients with advanced ovarian cancer that has spread inside the abdominal area. 

Side Effects

Some side effects you may experience are: 

• Nausea and vomiting
• Loss of appetite and weight loss
• Fatigue 
• Frequent infections 
• Easy bruising and bleeding 
• Hair loss
• Headaches and muscle aches
• Constipation or diarrhoea

It is not necessary that you experience all these side effects as everyone reacts to chemotherapy differently. Though these side effects may be quite upsetting, they are temporary and will stop once you are done with chemotherapy. 

Less commonly, some long-term side effects can occur such as infertility and permanent damage to the nerves, kidneys or bone marrow. Again, these side effects do not happen in everybody and largely vary depending on the type and duration of the chemotherapy you are receiving.  

Patient Management and Support

Getting diagnosed with cancer can be life-altering and you will need immense physical and physiological support to help cope with this disease. Apart from your close friends and family, your healthcare team will also offer various forms of support. 

In the beginning, your doctor will sit down and explain to you what exactly this disease is and what treatment plan has been drawn up. They will obtain your full informed consent about any procedures and you will be able to ask them about any concerns or queries you might have. Your GP can also refer you to various community services which are available in your area or a community nurse which may be available to you in your own home. You can read more about this here. There are also websites where you can seek financial or emotional support such as Macmillan Cancer Support. 

In addition, there is also an NHS service available, Enhanced Supportive Care (ESC), which aims to provide comprehensive support to people who are living with cancer. This support starts from diagnosis and is also available during the treatment duration, as well as post-treatment care. It can provide you with help to manage both physical and psychological side effects from chemotherapy as well as improve the quality of life for patients who have reached the end of their treatment options. 

There are certain things that you can do yourself to manage your side effects. Daily, gentle exercise and nutritious meals in small quantities can help as well as remembering to stay hydrated. Also, try to avoid getting cuts/scrapes and avoid people or places where you might contract an infection such as a cold or flu. Some people benefit from yoga or meditation to help with relaxation. Nausea and vomiting are also a common side effect and you can ask your doctor to prescribe anti-emetic medication to help combat this. 

Response Assessment and Follow-up

Your doctor will follow how you are responding to the chemotherapy you are receiving by taking blood samples and doing scans. The blood samples are used to check for an ovarian cancer protein known as CA 125.⁶ Not all women with ovarian cancer have high levels of CA 125, but if you do, your levels should fall after a treatment of chemotherapy.

Scans such as computed tomography (CT) and magnetic resonance imaging (MRI) can also be done to check if the chemotherapy has succeeded in reducing the size of the cancer or to check if the spread of the cancer has receded. This shows that the treatment is working.

Summary

Ovarian cancer is a cancer of the ovaries, which is found in people assigned female at birth. Cancer is abnormal and rapid growth of cells and it is treated with surgery or chemotherapy. 

Once ovarian cancer has been diagnosed, it will be staged and this staging can help to form an appropriate treatment plan. Both chemotherapy and surgery can be done for this type of cancer, depending on what stage the cancer is at. Chemotherapy might be offered on its own or in combination with surgery or sometimes, it might not even be needed. 

Chemotherapy for ovarian cancer uses platinum-based drugs or taxane-based drugs. Both these drugs can target rapidly dividing cancer cells and they might even be used in combination in order to destroy more cancer cells. In this type of cancer, usually, 6 cycles of chemotherapy are needed. It is commonly administered through your veins, or sometimes directly into your stomach.

There are several side effects to chemotherapy but these are only temporary. There are lots of support groups available to patients both within the NHS and in the community services which depend on your location. There is ongoing research being conducted into ovarian cancer in order to provide better and more targeted treatment for all patients afflicted by this condition.