Chemotherapy And Radiation Therapy For Feratoma Patients

Introduction to teratomas

A teratoma is a rare type of tumour which can contain different types of tissues from the three germ cell layers. Germ cells are a type of cell that develop into a reproductive cell, sperm cells and egg cells.

The different tissue types that may be found in a teratoma include muscle, hair, teeth and bone. Some teratomas have even been reported to contain complex structures, for example, organs or nerve tissues. They are typically found in the ovaries or testes, but they may occur anywhere in the body.¹ 

The cause of teratomas remains unknown, however, they are thought to arise as a result of DNA mutations (changes) in germ cells. Teratomas are most commonly benign (non-cancerous), however, occasionally they can be malignant (cancerous).

There are three main types of teratomas. They are categorised according to their characteristics and composition.

Mature teratoma 

A mature teratoma, also known as a dermoid cyst, is the most common type of teratoma. Usually, these tumours are benign and contain tissues from all three of the germ cell layers. These may include hair, bone, teeth, skin and sebaceous glands. 

Mature teratomas most frequently occur in the ovaries but may be found in other regions of the body. This type of teratoma is the most common type of ovarian germ cell tumour. 

Immature teratoma

An immature teratoma is a malignant type of teratoma containing undifferentiated cells. These types of teratomas can be aggressive and are capable of spreading to other parts of the body. Immature teratomas normally occur in children and adolescents and most commonly, but not exclusively, occur in the ovaries or testes.

Teratoma with malignant transformation

A teratoma with malignant transformation starts off as a benign teratoma. Over time, some areas of the teratoma develop cancerous characteristics and ultimately become malignant. This type of teratoma often requires a combination of surgical removal and additional therapies including radiation and chemotherapy, which can make this type of teratoma more difficult to treat.

Both chemotherapy and radiation therapy have important roles in teratoma treatment. These therapies are especially important if the teratoma exhibits malignant potential or transformation. In these cases, chemotherapy and radiation therapy are used to target and destroy any cancer cells that may have spread beyond the site of the initial tumour and any microscopic cancer cells that remain at the tumour site following surgery. Effective chemotherapy and radiation therapy can reduce the risk of recurrence and improve long-term survival rates.

Chemotherapy for teratoma patients

Explanation and goals

Following surgery to remove a malignant teratoma, there is a risk that some cancer cells may remain within your body. These can either be microscopic cells at the initial site of the teratoma or cancer cells that have spread to other areas of your body. Your oncologist or healthcare provider will be able to determine this risk based on your individual case, and may suggest chemotherapy to destroy these cells. 

Chemotherapy is defined by the National Cancer Institute as the use of drugs to stop the growth of cancer cells.

Adjuvant chemotherapy, also referred to as helper chemotherapy, is used to treat any cancer cells that may remain following your primary surgical treatment.² These cells can be difficult/impossible to detect using the currently available methods. As a result, your oncologist may recommend adjuvant chemotherapy to destroy any residual disease and therefore, reduce the likelihood of the teratoma recurring or spreading.³ However, it will also extend the length of your cancer treatment.

Common drugs used

There are many different chemotherapy drugs used to treat cancer. The specific drugs your oncologist prescribes to treat a teratoma may vary depending on the type of teratoma, specific tumour markers, the stage of the teratoma, and your overall health.

According to the American Cancer Society, most people assigned female at birth (AFAB) with germ cell cancer are treated with a combination of chemotherapy drugs. The most common drugs used in these cases include cisplatin, bleomycin, and etoposide. However, if treatment is unsuccessful or your cancer reoccurs, a different combination of drugs may be used.

Administration and duration

Your oncologist is responsible for determining the chemotherapy drug or combination of chemotherapy drugs that is best suited to your individual case. They will also consider the optimal dosage and timings of each treatment.

Side effects and management

Chemotherapy drugs target rapidly dividing cells. As a result, they harm both cancer cells and other non-cancerous cells in your body that reproduce quickly. Examples of these cell types include hair follicles, skin and mouth cells. The damage to these non-cancerous cells can lead to side effects, including:

• Constipation
• Diarrhoea
• Loss of appetite
• Hair loss
• Nausea and vomiting
• Mouth sores
• Fatigue

Individuals receiving chemotherapy are also at a higher risk of anaemia (low red blood cell levels) and neutropenia (low levels of white blood cells called neutrophils). 

Monitoring and follow-up

Teratoma patients undergoing chemotherapy require regular assessments to evaluate their response to treatment, manage side effects, and ensure their overall well-being. Key aspects of monitoring and follow-up for teratoma chemotherapy are:

• Physical examinations
• Imaging tests
• Blood tests
• Management of side effects
• Communication and patient support

The frequency and duration of monitoring and follow-up visits can vary depending on the specific treatment plan and the patient's response to chemotherapy.

Radiation therapy for teratoma patients

Explanation and goals

Radiation therapy or radiotherapy is a type of cancer treatment that uses high-energy radiation to kill or inhibit cancer cells. It works by destroying the genetic material in cancerous cells, which, in turn, prevents cell growth and division. 

Healthy cells can be damaged during radiation therapy, but they are more capable of repairing themselves than their cancerous counterparts. In addition, current radiotherapy methods can be targeted directly at the cancer and cause minimal damage to healthy surrounding tissues.⁴ Ultimately, the goal of radiotherapy is to treat the teratoma whilst minimising any side effects.

Types of radiation therapy

Several types of radiation therapy can be used to treat teratomas and other cancers. X-rays are the most commonly used form of radiation. However, other types of radiation do exist. The choice of the specific radiation therapy technique depends on factors such as the tumour's location, size, stage, and the overall treatment goals. Commonly used types of radiation therapy include:

• External beam radiation therapy (EBRT): This is the most common type of radiation therapy. It involves a machine outside the body that directs high-energy beams precisely at the tumour⁵
• Brachytherapy: In brachytherapy, radiation is delivered from radioactive sources placed directly inside or near the tumour. This technique allows for a high dose of radiation to be delivered directly to the tumour while minimising exposure to surrounding healthy tissues⁶
• Proton therapy: Proton therapy is a specialised form of radiation therapy that uses protons instead of X-rays. Protons can deliver radiation with precision, allowing for higher doses to be delivered to the tumour while reducing radiation exposure to nearby healthy tissues

The specific radiation therapy approach you will receive is determined by your radiation oncologist and healthcare team. They will take the characteristics of your individual case into consideration.

Planning and delivery process

The planning and delivery of radiation therapy involves multiple steps to ensure accurate and effective treatment.

It is important to note that the specific details of the planning and delivery process may vary based on individual circumstances and the radiation therapy technique. Your healthcare team will provide detailed instructions and guidance throughout the entire process.

Consultation and evaluation

The process begins with a consultation with a radiation oncologist who specialises in teratoma treatment. The oncologist will review your medical history, diagnostic imaging, and pathology reports to assess the tumour's characteristics, location, and stage. They will also discuss the goals of treatment and the potential benefits and risks of radiotherapy.

Simulation

A simulation session is used to precisely define the treatment area and aid in treatment planning. This may involve taking measurements, finding a comfortable treatment position, and using imaging techniques such as CT or MRI scans to identify the tumour's exact location and its relation to surrounding structures.

Treatment planning

Based on the simulation data and imaging results, a medical team develop a treatment plan. They determine the optimal radiation dose, the number and angles of radiation beams, and the shape of the treatment fields. The plan aims to deliver an effective dose to the tumour while minimising exposure to nearby healthy tissues.

Quality assurance

Before the treatment plan is finalised, it undergoes a comprehensive quality assurance process.

Treatment delivery

Once the treatment plan is approved, the scheduled radiation therapy sessions begin. The patient lies on a treatment table, and the radiation therapist positions them precisely according to the treatment plan. The treatment is painless and typically takes only a few minutes per session.

Monitoring and support

Throughout the treatment process, the patient is closely monitored by the healthcare team. Regular follow-up visits are scheduled to assess treatment response, manage side effects, and address any concerns or questions the patient may have. The healthcare team provides supportive care and adjusts the treatment plan as needed to ensure the best possible outcome.

Side effects and management

The most common side effect of radiation therapy is fatigue. Other side effects of radiation therapy can vary depending on the part of the body being treated. Possible side effects of teratoma radiotherapy can include:

• Fatigue
• Skin changes
• Hair loss
• Nausea and digestive issues

In some cases, teratoma radiation can also have long-term side effects, including fertility issues and secondary malignancies. It should be noted that not all patients will experience the same side effects.

Monitoring and follow-up

Your healthcare team will closely monitor your progress, provide the supportive care you require, and address any side effects or concerns you may have regarding the treatment. 

Combination therapy: chemotherapy and radiation

A combination therapy approach is often employed in the management of teratomas, particularly in cases where the tumour is malignant, recurrent, or has spread to other parts of the body.⁷

Rationale and timing

The rationale for using combination therapy in the treatment of teratomas is based on several factors, including the tumour's characteristics, stage, location, and the overall treatment goals. The combination of different treatment modalities aims to maximise treatment efficacy, reducing the risk of recurrence and improving patient outcomes.

In some cases, chemotherapy may be given before surgery to shrink the tumour and facilitate its removal. Radiation therapy can be administered before or after surgery, depending on factors such as tumour size, location, and the need to target specific areas at risk of recurrence.

Benefits and effectiveness

Using a combination approach to the treatment of teratomas offers several benefits. Key benefits and advantages to the use of combination therapy include:

• Enhanced treatment efficacy
• Improved tumour control
• Increased potency
• A more personalised approach
• Target micrometastasis (cancer cells that have spread from the tumour site)
• Improvement of overall survival

Side effects and management

The side effects of a combination approach to cancer treatment varies depending on specific characteristics of your treatment and health. The general side effects include fatigue, nausea and hair loss. Your healthcare team can address, provide guidance and manage your side effects throughout treatment. 

Prognosis and follow-up care

Prognostic factors

The prognosis (outlook) of teratomas can vary depending on several factors, including the tumour's location, stage, histology (malignant or benign), and the individual patient.

Outcomes and survival rates

Overall, the prognosis for teratomas is excellent, especially when diagnosed and treated early. However, the prognosis may be less favourable for malignant or advanced teratomas.

Importance of follow-ups

It is important to adhere to your recommended follow-up schedule as advised by your healthcare providers after teratoma treatment. Having a proactive approach to follow-up care is crucial for detecting any potential issues early and providing timely interventions.

Surveillance tests and imaging

Surveillance tests and imaging play an important role in monitoring teratomas after treatment and detecting any potential recurrence or spread. The frequency of surveillance tests and imaging depends on factors such as the tumour's characteristics, stage, treatment history, and individual patient factors. The healthcare provider will determine the appropriate surveillance schedule based on these factors and may adjust it as needed.

Summary

In summary, a teratoma is a rare type of germ cell tumour. The three types of germ cell tumours are mature teratomas, immature teratomas, and teratomas with malignant transformation. Treatment might include surgery, chemotherapy or radiotherapy. It is more common to use a combination of these treatments.