Clinical Applications of Brachytherapy - Essay Example

? Clinical Applications of Brachytherapy Brachytherapy is an advanced method for treating cancer. Radioactive seed or sourcesare placed in or near the tumor. This gives a high radiation dose to the tumor. The radiation given shrinks the tumor and kills the cancerous cells. There are two types of Brachytherapy treatment. They include interstitial and contact. In interstitial brachytherapy, radioactive sources are placed directly into the tissues of the affected organ while in contact brachytherapy the radioactive sources are placed in a space next to the targeted tissues. Brachytherapy works by having small catheters or applicators placed in the tumor. The catheters are connected to a high-dose rate offloader machine. This machine contains a very high radioactive iridium pellet at the end of a wire. The radioactive pellets under computer control are pushed inside the catheters or applicators. The computer controlled machine controls the period the pellets stay inside the catheters and at what position inside the catheter should the pellets release their radiation. With accurate placing of catheters inside the tumor, brachytherapy provides a very precise method for treating cancer (Fischer, 2011). Once treatment has being accomplished, the catheters or applicators are removed. This ensures that there are no radioactive seeds left in the patient’s body. The exact treatment depends on the size, location and shape of the tumor. Brachytherapy is used to treat the following types of tumors. They include prostate cancer, breast cancer, lung cancer, cervical cancer, head and neck cancer and sarcomas. This therapy enables the application of high radiation dose in a small affected area. This reduces the risk of exposing the adjacent healthy tissues to radiation. This reduces the side effect experienced by the patient after treatment. One of the advantages of this therapy is that the recovery period is short and the patients resume their daily activities after a few days (Fischer, 2011). Prostrate brachytherapy is used in the treatment of prostate cancer. Prostate gland is located under the bladders and in front of the rectum. It is important to focus the radiation on the prostate gland to avoid exposing radiation to the nearby healthy cells. There are two methods used for prostrate brachytherapy. They include; permanent seed implantation and high-dose rate temporary brachytherapy. Permanent seed implantation is used in early-localized prostate cancer. To carry out the procedure an ultrasound probe is inserted through the rectum. This probe captures images that show the size and shape of the patient’s prostate gland. This is done to determine how to deliver the right radiation dose.100 radioactive seeds are then injected directly in to the prostrate. An ultra sound probe helps guide the oncologist in inserting the radioactive seeds into the right position (Langley et al., 2008). These radioactive seeds release radiation at a low dose rate for a given period and remain in the prostate gland permanently. The radiation released by the seeds kills the cancerous cell in the prostate gland. Due to radioactive decay, these radioactive seeds disintegrate over time and become safe to stay in the prostate gland (Mason & Moffat,2010). This procedure requires no incision and is carried out on as a day-case procedure. It also has a good side effects profile therefore its safer compared to other methods of treatment (Fischer, 2011). When the seeds are active the patients must take some precautionary measures such, staying away from children to avoid exposing them to radiation and using a condom during sexual intercourse as there is a possibility of a seed being expelled on ejaculation (Lucas, 2004). High-dose, rate temporary brachytherapy involves placing very tiny catheters into the prostate gland and then giving a series of radiation treatment through the catheters (Mason & Moffat, 2010).A computer-controlled machine pushes the radioactive seeds one by one into the catheters. The oncologist is able to control the dosage each part of the prostate gland receives, since the computer controls how long the radioactive materials remain in the catheters. The tumor receives a high dosage while the rectum and urethra receive low dosage. The ability to modify the dosage after the catheters have being inserted is one of the advantages of this method. The catheters are then removed ensuring that there are no radioactive seeds left in the prostate. Some of the side effects of high dose-rate Prostate Brachytherapy include difficulty in urinating and erectile dysfunction (Toye et al., 2010). Breast brachytherapy is performed after the tumor has being removed. It is used to give radiation therapy to the breast. There are two methods used for breast Brachytherapy. The first method involves placing multiple catheters into the breast, which surrounds the area where the tumor was removed. The use of multiple catheters offers more flexibility and is more targeted form of administering radiation into the breast. These catheters are carefully placed to allow maximum targeting of radiation to the treatment area while sparing then surrounding healthy breast tissues (Chadha et al., 2009). The catheter are attached to an off loader machine which delivers a radiation dose through the multiple catheters. The second method involves placing a single catheter in the breast, which has a balloon that inflates once inside the breast in the cavity where the tumor existed. The single catheter is connected to an off loader machine which delivers the radiation dose through the catheter and into the balloon (Arthur et al., 2011). In both methods, radioactive pellets are inserted in the catheters twice daily for five days. The radioactive pellets are inserted using a high dose-rate offloading machine then the catheters are removed (Dickler et al., 2009) Breast brachytherapy is considered safer than the standard external radiation since it is more targeted (Ravi et al., 2011). Using breast brachytherapy treatment is completed within one week while treatment using the standard external radiation takes up to six weeks. Therefore, most workers and the elderly prefer the breast brachytherapy since the survival chances are the same. Women with early breast cancer are mostly eligible for breast brachytherapy. This therapy also requires that the tumor is small which clear surgical margins after lumpectomy. It is also preferable that there are no lymph nodes containing cancer (Njeh et al., 2010). One of the advantages the methods is that radiation is focused on the part of the breast where the tumor was removed. This allows a small region to be radiated hence less radiation affects the heart, lungs, ribs muscles and skin. Some of the possible long-term side effects of this form of treatment are fibrosis and Fat necrosis. Fibrosis involves the change in texture in breast tissue making the breast to be harder. The risk of developing fibrosis depends on the radiation dose that the patient received during treatment. Fat necrosis involves the breakdown of some breast tissue causing local irritation of the tissue. Fat necrosis affects small proportion of the patients treated using breast brachytherapy. Cervical brachytherapy is used to treat early-localized cervical cancer. Cervical cancer occurs when malignant tissues form in the tissues of the cervix. Cervical cancer can either be treated with; Low dose rate (LDR), medium dose rate (MDR) and high dose rate (HDR) brachytherapy (Atara et al., 2010).LDR brachytherapy uses radioactive sources that emit low radiation. To deliver the required dose of radiation the radioactive sources remain near the tumor for an extended period. In contrast, in HDR brachytherapy the radioactive sources used deliver higher radiation emissions giving the radiation dose in a short period. This enables the patient to receive treatment on outpatient basis. To perform the procedure a various scans are carried out to establish the size and location of the malignant tumor (Petric et al., 2011). This enables the oncologist to determine the amount of radiation dose required to destroy the cancerous cells and which tissues in the cervix to be targeted .The oncologist then places applicators into the cervix. The applicators are connected to a computer-controlled machine referred to as the offloader machine (Dimopoulos et al., 2008). The offloader then sends small radioactive sources though the applicators to the treatment area in the cervix. The radioactive sources are left in the treatment area for a predetermined period. The computer controlling the offloader machine is programmed to ensure accurate placement of the radioactive sources. Therefore, a precise and accurate dose is delivered to the tumor in the cervix. This reduces the radiation damage in neighboring tissues or organs (Cetina et al., 2009). After the predetermined time has elapsed, the radioactive sources are removed through the catheter and back into the offloader machine. Some of the possible long term effects of cervical brachytherapy include; early menopause, bowel discomfort, urinary discomfort and vaginal fibrosis (Hayat, 2010). References Arthur, D. W., Vicini, F. A., Beitsch, P. D., Kuerer, H. M., Haffty, B. G., Keisch, M., & Lyden, M. R. (October 01, 2011). Six-year Analysis of Treatment-related Toxicities by the American Society of Breast Surgeons MammoSite Breast Brachytherapy Registry Trial in Patients Treated with Accelerated Partial Breast Irradiation. International Journal of Radiation Oncology*biology*physics, 81, 2.) Atara Ntekim, Adeniyi Adenipekun, Bidemi Akinlade and Oladapo Campbell

, & Ntekim,. (2010). High Dose Rate Brachytherapy in the Treatment of Cervical Cancer: Preliminary Experience with Cobalt 60 Radionuclide Source—A Prospective Study. (Clinical Medicine Insights: Oncology, Volume: 2010, Issue: 4.) Libertas Academica. Cetina, Lucely, Garcia-Arias, Alicia, Candelaria, Myrna, Cantu?, David, Rivera, Lesbia, Coronel, Jaime, Bazan-Perkins, Blanca, ... Duen?as-Gonza?lez, Alfonso. (2009). Brachytherapy versus radical hysterectomy after external beam chemoradiation: a non-randomized matched comparison in IB2-IIB cervical cancer patients. (BioMed Central Ltd.) BioMed Central Ltd. Chadha, M., Yoon, H., Feldman, S., Shah, N., Moore, E., & Harrison, L. B. (January 01, 2009). Partial breast brachytherapy as the primary treatment for breast cancer diagnosed after mantle radiation therapy for Hodgkin's disease. American Journal of Clinical Oncology, 32, 2, 132-6. Dickler, Adam, Ivanov, Olga, & Francescatti, Darius. (2009). Intraoperative radiation therapy in the treatment of early-stage breast cancer utilizing xoft axxent electronic brachytherapy. (BioMed Central Ltd.) BioMed Central Ltd. Dimopoulos, J. C. A., De, V. V., Berger, D., Petric?, P., Dumas, I., Kirisits, C., Shenfield, C. B., ... Po?tter, R. (January 01, 2008). Inter-observer comparison of target delineation for MRI-assisted cervical cancer brachytherapy: Application of the GYN GEC-ESTRO recommendations. Radiotherapy and Oncology, 91, 2, 166-172. Fischer, L. M. (2011). Brachytherapy: Types, dosing, and side effects. Hauppauge, N.Y: Nova Science Publishers. Hayat, M. A. (2010). Ovarian cancer, renal cancer, urogenitary tract cancer, urinary bladder cancer, cervical uterine cancer, skin cancer, leukemia, multiple myeloma and sarcoma. Dordrecht: Springer. Langley, S. E. M., Laing, R. W., & Shah, J. (2008). Prostate brachytherapy in clinical practice. London: Springer. Lucas, J. N. (2004). Trends in prostate cancer research. New York: Nova Biomedical Books. Mason, M., & Moffat, L. E. F. (2010). Prostate cancer. Oxford: Oxford University Press Njeh, Christopher F, Saunders, Mark W, & Langton, Christian M. (2010). Accelerated Partial Breast Irradiation (APBI): A review of available techniques. (BioMed Central Ltd.) BioMed Central Ltd. Petric?, P., Hudej, R., & Marolt-Mus?ic?, M. (January 01, 2009). MRI assisted cervix cancer brachytherapy pre-planning, based on insertion of the applicator in para-cervical anaesthesia: Preliminary results of a prospective study. Journal of Contemporary Brachytherapy, 1, 3, 163-169. Ravi, Akkamma, Lee, Susan, Karsif, Karen, Osian, Adrian, & Nori, Dattatreyudu. (2011). MammoSite multilumen catheter: Dosimetry considerations. (Journal of Cancer Research and Therapeutics (ISSN: 0973-1482) Vol 7 Num 1.) Medknow Publications on behalf of the Association of Radiation Oncologists of India (AROI Toye, W, Das, R, Kron, T, Franich, R, Johnston, P, & Duchesne, G. (n.d.). An in vivo investigative protocol for HDR prostate brachytherapy using urethral and rectal thermoluminescence dosimetry. Elsevier Ireland Ltd. Read More