Prostate cancer: Prostate cancer is the most commonly diagnosed cancer in men within the United States, with 200,000-300,00 new cases being detected annually. The term cancer generally refers to the abnormal growth of certain cells within the body. Unlike normal cells, the body cannot stop the growth of cancerous cells. If untreated, these cells grow and cause problems within the area they originated from, and/or they spread to other parts of the body and cause a multitude of symptoms. Historically, the treatment for prostate cancer has relied on three modalities: surgery, radiotherapy, and hormonal therapy. A summary of the pros and cons of each are presented below. Treatment options: Surgery Surgical therapy involves complete removal of the prostate gland ("radical prostatectomy") with or without taking samples of the adjacent lymph nodes. Although newer techniques such as nerve sparing have improved the side effects of surgery, many men are still left with erectile difficulty or urinary leakage. The side effects associated with surgery are very much dependent on the experience and expertise of the urologist performing the prostatectomy. Regardless of the urologist however, many men with "locally advanced" prostate carcinoma (elevated PSA, Gleason, or T-stage) have prostate cancer cells that have crept outside prostate gland itself; removal of the prostate gland alone often leaves these cancer cells behind. Following surgery, studies that have examined the prostate glands of men who showed high risk features (PSA above 10, Gleason score 7 and/or T3/T4 disease) indicate that "positive margin" and "extracapsular extension" rates are at least 35%. This increases the change of a tumor recurrence. Radiation therapy Radiation therapy, which has been used to treat cancer since approximately 1900, has also proven to be an effective means of treating and curing prostate cancer. Radiation therapy is used to help cure most known cancers by using X-rays to destroy cancer cells. The radiation damages the DNA of cells, leading to cell death. Fortunately, the radiation oncologist designs the treatment in such a way that the X-rays preferentially damage the DNA of cancerous cells rather than those of normal tissues, thus allowing the eradication of cancers while minimizing damage to the surrounding normal organs. There are two different types of radiation therapy used to treat prostate cancer: 1) external beam radiation therapy (see details below); and 2) prostate seed implant (will be discussed in a separate section). Hormonal therapy Hormonal therapy in prostate cancer refers to medications given to patients that reduce testosterone levels. These can be given either in the form of pills or injections. The side effects generally associated with hormone therapy, if given for six months or less, include hot flashes, moodiness, loss of libido and impotence. The vast majority of these symptoms are temporary and will resolve after the hormone therapy is discontinued. While effective in temporarily slowing the growth of prostate cancer cells and shrinking the prostate gland as a whole, hormone therapy by itself does not cure the disease. Studies have shown that hormone therapy given before and during radiation therapy significantly improves cure rates in certain patients, especially those men with advanced prostate carcinoma. Studies have not shown, however, any benefit to giving hormone therapy to men before radical prostatectomy. Modern Radiation Therapy: The radiation that most cancer patients receive is created by machines called linear accelerators. Radiation is created when these machines produces high voltages, which gives the necessary energy to electrons to produce a beam of radiation. There is ample evidence--both clinically and biologically--to suggest that increasing the radiation dose to the tumor leads to a greater likelihood of killing the cancer cells. Prior to the introduction of so-called "conformal radiotherapy", increasing doses to the tumor meant increasing doses to the surrounding normal organs as well. Nowadays, conformal radiotherapy allows the radiation oncologist to deliver higher doses to tumors, while also keeping doses to surround tissues to a minimum. Simply stated, patients can now enjoy improved rates of cure with a minimal chance of side effects. Conformal Radiotherapy The techniques used to deliver radiation to the prostate have dramatically changed over the past decade. Instead of using plain, diagnostic X-rays to estimate the location the prostate, CT scans (performed before any radiation is delivered) are now used to accurately determine the location of the prostate, seminal vesicles, bladder, rectum, and penile bulb. This information is crucial since the size and shape of the prostate, along with its anatomic relationship to the bladder and rectum, can differ greatly between individuals. This allows the radiation oncologist to design a three-dimensional ("3-D") treatment plan specifically designed for each individual patient. Using special software designed at The University of North Carolina Department of Radiation Oncology, the pelvic anatomy of a patient can be reconstructed in 3-D based on the CT scan. This becomes an integral part of the conformal radiation treatment planning. By knowing the specific anatomy of the individual patient, the radiation oncologist and physicist will know the amount of radiation delivered to the prostate, seminal vesicles, bladder, rectum, and penile bulb. This information will allow your UNC physicians to more accurately deliver radiation to the cancer while decreasing the dose to the surrounding organs. Conformal radiation therapy allows patients to safely receive higher doses of radiation than are typically offered at other cancer centers (typically 72 Gy or less; the unit of radiation dose is the Gray, abbreviation: Gy). At UNC, we routinely treat patients with prostate cancer to 78 Gy. These higher doses have not only lead to excellent cure rates in early stage prostate cancer, but also much improved cure rates in patients with locally advanced prostate cancer, many of whom are considered "incurable" by surgery. Using advanced planning and delivery techniques, we target the radiation to the prostate while avoiding the adjacent organs. Because radiation doses to the bladder and rectum are minimized, side effects are likewise minimal. Patients may experience mild discomfort on urination, a slight increase in the frequency of urination, and a loosening and increased frequency of bowel movements. These special techniques also limit radiation doses to areas that are thought to result in erectile dysfunction. We now expect 60-70% of patients to retain their potency status after conformal radiotherapy. Of the remainder who do experience erectile dysfunction after radiation, 65-75% regain full potency with the use of Viagra. Intensity Modulated Radiation Therapy Intensity modulated radiotherapy is commonly known by its acronym "IMRT". IMRT is a more advanced form of 3-D conformal radiation therapy. The general goal of IMRT is to give a large dose of radiation to the tumor while sparing the adjacent normal tissues. Because radiation doses to the surrounding structures (such as the bladder and rectum) are limited, higher doses can be directed to the prostate, thus allowing a better chance of cure. IMRT involves two unique components, which together allow unprecedented accuracy of dose delivery. The first component involves what is called "inverse dose planning". Prior to the availability of IMRT, physicians had only limited options with respect to the kinds of treatment plans that could be used. With IMRT, the radiation oncologist "tells" the treatment planning system to create a plan that can deliver the total radiation dose that he or she feels can be tolerated safely by the patient while still maintaining the desired high dose to the prostate. The computer planning system then goes through millions of calculations and possibilities in an attempt to design an "ideal" treatment plan. The best of these plans are then presented to the radiation oncologist, who, together with the physicist, choose the best plan for the individual patient. The second major component to IMRT is the actual delivery of the chosen treatment plan. In order to deliver such complex plans, proper equipment is required. At minimum, this equipment should include a newer generation linear accelerator that minimizes treatment errors. A special attachment that is placed on the head of the linear accelerator is also essential. These special attachments are called multi-leaf collimators ("MLC"). The MLC's contain multiple small leaflets that both shape the beam to the desired specifications, and control the intensity of the beam. Intensity Modulated Radiation Therapy at UNC: A typical course of radiation therapy for prostate cancer at the UNC Department of Radiation Oncology consists of seven weeks of daily treatments, five days per week. The following is a summary of what you, the prostate cancer patient, can expect when you receive a radiation therapy consultation: 1) Consultation with the radiation oncologist - The radiation oncologist will perform a history and physical examination. Your medical records and radiologic studies will be reviewed and interpreted. During this appointment, your treatment options (observation, surgery, IMRT, seed implantation, and hormones), and prognosis, will be discussed. An anatomical overview of the prostate and the surrounding organs will be shown. The risks and benefits of the different treatment options will also be presented. Your case will also be discussed at the UNC Genitourinary Multidisciplinary Conference, which is held every Thursday afternoon in the Department of Radiation Oncology. During the conference, a UNC pathologist will review your biopsy results, a UNC radiologist will review your films, and your history will be review by radiation oncologists, urologists, and medical oncologists. This multidisciplinary approach to prostate cancer helps ensure accurate diagnosis and staging, as well as allow each type of cancer specialist from UNC to have a voice in your treatment options. 2) IMRT planning - Following the consultation, your first step in beginning IMRT is scheduling a special CT scan within our Department. Several days later, a simulation based on that CT scan will be performed. The simulation and the CT scan each take approximately 30 minutes. On the day of simulation, you will be given a free parking pass--our Department offers free parking to all patients receiving radiation therapy at UNC. This special parking is located about 30-40 steps from the entrance to our Department. 3) Daily treatments - Your treatments will be delivered Monday through Friday, five days per week. Treatments are delivered from 8:00 AM until 4:30 PM, and you are able to choose a time that is most convenient for you. Once you check in at the Department's front desk, you will typically have only a 5-10 minute wait before treatment. The radiation treatment itself only takes an additional 5-10 minutes to complete. During the treatment, you are asked to keep your bladder full. In total then, you typically spend approximately 30 minutes daily in the Department of Radiation Oncology. Why Intensity Modulated Radiation Therapy? First, many doctors and patients now prefer minimally-invasive and/or non-invasive procedures since the need for incisions, major surgery, and hospitalization can be avoided. Because of advances in radiation therapy technology discussed above, surgery and radiotherapy now offer comparable prostate cancer cure rates. Second, while there are exceptions, most men diagnosed with prostate cancer are greater than 60 years of age, and may have one or more pre-existing conditions (hypertension, coronary artery disease, diabetes, asthma, etc.) that make surgery a less attractive treatment option. With IMRT, there is no need to adjust medications or worry about any adverse effects sometimes associated with anesthesia. Also, there is no need for prolonged catheterization when opting for IMRT. Finally, newer treatment techniques like IMRT can reduce the likelihood of impotence as a side effect. Of all the options for treating prostate cancer, radical prostatectomy (even with bilateral nerve-sparing procedures) is associated with the highest rate of impotence. If impotence does occur following surgery, it occurs immediately thereafter. When impotence occurs after radiation therapy, it instead tends to develop gradually over a several year period, not immediately after treatment. Also, if erectile dysfunction does develop, the response rate to Viagra is approximately 75%. Why should I receive IMRT at UNC? While many people own musical instruments, it takes well-trained, experienced musicians, composers, and conductors to create the ideal sound. In much the same way, simply choosing IMRT for the treatment of prostate cancer does not in and of itself guarantee better results. The treatment facility must have the latest technology (CT scanner, computer planning system, linear accelerators, and bi-focus multi-leaf collimators), and the physicians must have received special training in IMRT, both in terms of the designing of plans, patient treatment, and experience with follow-up care. Experienced physicists and dosimetrists who are familiar with the IMRT software planning system are also crucial. The radiation therapy technologists (medical professionals who position the patients on a daily basis and operate the machines that actually deliver the radiation) must be familiar with how to implement IMRT. Finally, the oncology nursing staff should also be experienced not only in caring for patients with prostate cancer, but also in recognizing and preventing any of the symptoms that are sometimes associated with IMRT. At UNC, a tremendous amount of research has gone into the development, planning and quality assurance of the specially-designed software for implementing IMRT. The UNC Department of Radiation Oncology was the first in the State of North Carolina to treat cancer patients using IMRT. In fact, UNC was one the first centers in the nation to use IMRT. To date, over 900 cancer patients have been treated with this state-of-the-art form of radiation therapy. UNC not only posses the most advanced equipment to design and implement IMRT, but also has the most experienced and dedicated staff (physicians, physicists, dosimetrists, radiation therapists and nurses) in the region. Summary: Before you decide on your cancer therapy, be sure to ask your treating physician about the latest data regarding intensity modulated radiation therapy. Even if you ultimately decide on surgery as your primary form of treatment, a one-hour consultation with a radiation oncologist specializing in prostate seeds and IMRT is the only way to ensure that you have weighed all the treatment options, and can make an appropriate, informed decision. Advances in the field of radiation oncology now allow unprecedented cure rates for prostate cancer with minimal side effects and without the need for any invasive procedures. To refer patients for a discussion of treatment options, prognosis, second opinion, or specialized procedures, please call the UNC Department of Radiation Oncology at (919) 966-7700.

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