Prostate cancer is the fourth most common cancer in inIndia, with a median age of 72 years at diagnosis. The inU.S. the range of 265,000 new cases each year, with 36,000 deaths annually. The treatment of radiation and radio curability of prostate cancer depends on the radiation dose delivered to the prostate. In a meta-analysis of 22 trials covering 11,927 patients, it appears that a dose of 70 Gy of radiation resulted in a better response. Increasing the dose beyond this increases the rate of clinical response, pathological and biochemical.
Kupelian et al (IJROBP, 61, 415-9, 2005) published data on the nine institutions in 1325 patients with T1 and T2 lesions of the prostate. Disease-free survival of 8 years PSA (PSADFS) was 62% and 72 Gy dose was an independent predictor of outcome. Dose-response curves for conformal radiotherapy is a sigmoid curve which means that higher doses must be submitted to obtain a higher cure rate. If you look at the PSA nadir is a serum PSA level of less than 1.oo ng / ml was observed in 90% of patients who received more than 75 Gy. The rate of positive biopsies after 5 years in patients who received 80 Gy of 4% only. So the dose escalation in carcinoma of the prostate 3D CRT leads to a medium risk and high profit after 70 Gy in response and toxicity as well. Zietman et al, in 2005 published a comparison between the high-dose compared with conventional 3D-CRT, 393 patients were randomized between conventional (n = 197) and 3D CRT (n = 196). Determined by the study of disease-free survival at 5 years (DFS) was 80.4% compared with 61.45 3D CRT in patients receiving 70 Gy. I LOE 3D CRT displays without increasing the dose to reduce gastrointestinal complications and improve 70-78/79.2 Gy radiation dose reduces the failure rate.
According to a paper published by the RTOG Ryu JK et al (IJROBP 54, 1036-1046) seminal vesicle Prostate irradiation ads or no increase in gastrointestinal morbidity gastrourinary later. PD Hinduja National Hospital, 51 patients were treated from 1997 to 2002 with an average dose of 72 Gy, acute rectal toxicity was found to be grade 0 (4 patients), 1 (31 patients) class, and 2 (16 patients) class, while late toxicity class 0 (41 patients), 1 (3 patients) and grade 2 class (2 patients) was observed. Thus the evidence is that the rate of increase in the radiation dose of 70 Gy over increased rectal pain.
IMRT in prostate cancer indicate a change in the radiation field intensity beamlets. It also includes a high-level structure of the target dose conformality, automatic selection of files – inverse treatment planning and the concept of field homogeneity across. So people with IMRT can increase the radiation dose does not increase the side effects that may improve local control of the disease. However, remember that with the increasing amount of exposure to moderate doses of radiation increase the radiation on the cancer can occur in the long term.
Before starting IMRT for prostate cancer after the basic steps required (i) the preparation of this pelvicst (restriction), (ii) the damaged part CECT IRIS 5 mm (iii) restrictions on the amount of tissue targeting of risk, and (iv) evaluation of the dose distribution ( v) generate DRRs (digital radiography reconstruction) (vi) generation portal imaging. Clinical target volume (CTV) for prostate cancer, including prostate and seminal vesicles. The seminal vesicles can be removed from the CTV after 50 Gy the number of shares less than 10%. The volume of the treatment plan (CTV PTV0 taken as a margin of 10 mm in the direction of the skull-posterior and 7 mm in the other direction. Positions on your back with knees treating rectal suppository inserted and fixed 15 minutes before RT. Patient requires 750 ml of water 1 hour before the start of RT and 300 ml immediately before RT portal images. often taken to improve the position of the patient. using 18 MV photon beam gantry 116 and 224 degrees and firing techniques. every day treatment period of less than 8 minutes usually 285 monitor units delivered dose. should be kept under 60 Gy maximum anal.
Hypofractionated IMRT fraction when the number was reduced to 28, and a total dose of 70 Gy was delivered. It is seen that the rectal and bladder complications of hypo-fractionated IMRT, but long-term follow-up results were not available.
To conclude IMRT prostate carcinoma is a well-established treatment modality. It helps to increase the amount of radiation delivered to the tumor and ensure a lower dose reaches the normal structure.