Comparison of hyperfractionated conformal photon with conformal mixed neutron/photon irradiation in locally advanced prostate cancer.
In an attempt to improve the probability of complication-free local control for patients with locally advanced prostate cancer, a series of dose-finding studies have been conducted at Wayne State University using conformal neutron and hyperfractionated photon irradiation. In total, 96 patients with locally advanced prostate cancer (T3/T4 N0/N1 M0, and/or Gleason score > or = 8) were treated in two prospective studies. Forty-seven patients received conformal neutron/photon (15 NGy + 18 PhGy) and 49 patients were treated in a dose-escalation study using conformal photons (25 patients/78 Gy and 24 patients/83 Gy minimum dose). The median follow-up for both studies was 20 months (range 6-36 months). There was no significant difference in the rate of chronic gastrointestinal (GI) or gastrourinary (GU) morbidity between the two groups. However, the neutron treated patients had a significantly higher rate of moderate (14%) and severe (12%) hip stiffness. The rates of prostate-specific antigen (PSA) decline and 12-month negative biopsy were comparable. In conclusion, the therapeutic gain of neo-adjuvant hormonal therapy in combination with photon hyperfractionation to 83 Gy appears identical to that seen with the mixed neutron-photon dose of 15 NGy + 18 PhGy. Further efforts at improving the therapeutic ratio of radiotherapy for patients with locally advanced prostate cancer should be undertaken.
Forman
J D
JD
Department of Radiation Oncology, Wayne State University, Detroit, MI 48201, USA.
Shamsa
F
F
Maughan
R L
RL
Duclos
M
M
Orton
C
C
D000230:Adenocarcinoma / Q000097:blood / Q000473:pathology / Q000532:radiotherapy*; D000368:Aged; D000369:Aged, 80 and over; D004064:Digestive System / Q000528:radiation effects; D005214:Fast Neutrons; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D017785:Photons; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy / Q000009:adverse effects / Q000379:methods; D014566:Urogenital System / Q000528:radiation effects
D017430:Prostate-Specific Antigen