Date: 30th September 2024 | Issue #2
‘Nimekuja kuchomwa’ This is a very common statement in most cancer centres across the country with patients undergoing radiation therapy. Most new patients still have not come to terms with their various diagnoses and are very apprehensive, with fear written all over their faces. They are always in the company of relatives who appear sicker than the patients. Patients go through various psychological stages after a cancer diagnosis. Others even have their daily lives changed completely. The role of stakeholders involved in the patient journey cannot be ignored and specifically the support from relatives and friends. In Kenya, where Swahili is the national language, most patients will be heard referring to radiotherapy as ‘kuchomwa’ a Swahili word directly translated to being burnt. As a result, patients are usually frightened of the whole process. It is not ‘kuchomwa’. There is a need for people to have a better understanding of this modality in cancer management and an overview of what it entails.
Radiotherapy uses ionizing radiation delivered at high energies to either treat or control the symptoms of a disease, including cancer. The radiation may be from photons (X-rays) or particles such as protons, electrons and gamma radiation. Radiation is energy in transit that is neither seen nor felt hence, the treatment process is completely painless. Radiotherapy may be used to debulk a tumor before surgery, reduce recurrence of a disease after surgery or chemotherapy, suppress the immune system before organ transplant or to control the symptoms of a disease in the case of metastasis. It can also be used in emergency conditions such as spinal cord compression, airway obstruction, superior vena cava obstruction, bleeding and brain metastasis.
Radiotherapy can be delivered from outside the body by a machine that rotates around the patient as in external beam radiation therapy. It may also be delivered from a source placed on or near the tumor (brachytherapy) or can be ingested (radionuclide therapy). The choice of the modality depends on the tumor type, stage at diagnosis, the patient’s general health, availability of the treatment modalities and the patient’s preferences. Radiotherapy can be applied as an individual treatment or it can also be combined with radiosensitizers such as radionuclides and chemotherapy.
Before administering radiotherapy, the patient receives a general explanation of the procedure and expected outcome and side effects. In addition, any arising concerns by the patient are addressed. Radiotherapy involves three major steps, including simulation, treatment planning and actual treatment delivery.
Simulation is a mock treatment process and involves obtaining images for treatment planning. With improved technology, 4-D images are preferred but 3-D images are the most commonly used. These images are obtained using a CT scanner. The patient is placed in the treatment position and accurate documentation is done to ensure reproducibility, accuracy and precision during the actual dose delivery. Special customized immobilization devices are used to ensure patient comfort. Semi-permanent marks and tattoos are made on the patient’s skin to help in positioning. The images obtained in simulation are forwarded to the treatment planning system.
During treatment planning, dedicated computer systems are used to guide the machine on how to direct the radiation to the target. The healthy organs in the beam’s path are delineated together with the target. Margins are given around the target organ to account for clinically obscure disease and a margin for error during daily treatment. Various body organs have different tolerance levels of radiation. A multidisciplinary radiotherapy team consisting of a radiation oncologist, dosimetrist, radiation therapist, and a medical physicist work jointly to ensure that a tumoricidal dose is delivered to the target organ and as low as reasonably achievable radiation reaches the surrounding healthy tissue. Once the best plan has been agreed upon by the team, the patient is scheduled to start treatment.
Before the actual treatment delivery, the patients’ details are confirmed. The machine’s performance status is confirmed by quality checks to ensure proper functioning, precision and accuracy during dose delivery. The patient assumes the same position as in the simulation throughout their course of treatment. The radiation therapists are guided by the skin marks made during the simulation. This procedure takes about 20 minutes from the time the patient walks into the room to discharge. Treatment sessions are usually five (5) times a week, allowing the patient to rest on weekends.
Follow-up on patients undergoing radiotherapy is done during weekly appointments with their oncologists. Lab works are ordered to monitor the prognosis and the patient’s general health. Patients may experience some side effects, which are both patient- and site-specific. The common ones include fatigue, loss of appetite, unintentional weight loss, pain, and discomfort. Appropriate advice is usually given on managing the various side effects, medications may be prescribed, and in extreme cases, treatment may be suspended. After completing the full course of radiotherapy, patients are seen periodically for up to 5 years, with the first appointment after three (3) months. Imaging tests may be ordered together with lab work to monitor recurrence and prognosis.
Radiation therapy may also be indicated in other benign conditions such as blood irradiation to prevent transfusion associated with graft versus host disease, treatment of keloid scars, gynecomastia, and acoustic schwannomas among others.
Christine is a member of the Outreach Division at ICRF Kenya and a final year Bachelor of Radiography (Radiation therapy option) student at Jomo Kenyatta University of Agriculture and Technology.