| Abstract: |
Prostate cancer is the second most common form of cancer in American males, accounting for some 40,000 deaths per year. Accepted treatment modalities for organ-confined disease are surgery and radiation therapy. Radiation therapy can be delivered with teletherapy beams of high energy x-rays, or by permanent implantation of radioactive seeds (brachytherapy). Long-term biochemical failure in permanent prostate implants and in external beam treatments continues to occur in as many as 20% of patients. Improvements in local control via dose escalation are currently limited by normal tissue complications in the rectum, urethra, and bladder. Magnetic Resonance Spectroscopy (MRS) can identify tumor 'hot spots' within the prostate, Registration of MRS with CT images permits optimized teletherapy treatment planning by use of inverse treatment planning and 'sliding window' Intensity Modulated Radiation Therapy (IMRT) dose delivery. Similarly, registration of MRS with Trans-Rectal UltraSound (TRUS) images permits improved brachytherapy dose conformity by use of Integer Programming treatment planning and conformal I-125 or Pd-103 seed implants. Both techniques incorporate dose escalation to tumor cells and normal tissue dose sparing. |
