Pion conformal radiation of prostate cancer: results of a randomized study.

Purpose: To compare the efficacy of pion radiation therapy with conventional external beam photon therapy, for the treatment of locally advanced stage T3/4, N0, M0 adenocarcinoma of the prostate.

Methods And Materials: Two hundred seventeen eligible patients were randomly allocated to either photon or pion therapy. No adjuvant hormone therapy was used.

The relative biological effectiveness of the modulated proton beam at TRIUMF.

Purpose: The purpose of this study was to determine the relative biological effectiveness (RBE) of proton beam and to study its dependency on fraction number.

Methods: The relative biological effectiveness (RBE) of fractionated protons compared with 60Co gamma-rays was investigated for the acute mouse skin reaction. The 80 MeV protons generated at the TRIUMF cyclotron were spread out from 7 to 25 mm to irradiate entire legs.

Watchful waiting or watchful progression?: Prostate specific antigen doubling times and clinical behavior in patients with early untreated prostate carcinoma.

Background: Prostate specific antigen doubling time (PSAdt) is a dynamic model of prostate tumor biology. It predicts aggressive disease and subsequent clinical recurrence after radical treatment. However, as yet there is only limited evidence for its validity in the watchful waiting population.

Impact of nicotinamide on human tumour hypoxic fraction measured using the comet assay.

Background And Purpose: Nicotinamide has been shown to reduce hypoxia in experimental tumours, but there are no data that measure the hypoxic fraction at the time of irradiation in humans. This study investigates whether nicotinamide with radiation can reduce human tumour hypoxia.

Materials And Methods: Twenty-two patients undergoing palliative radiotherapy for treatment of accessible metastatic tumours were exposed to two doses of radiation (3.

Four-week arc radiotherapy for B2-C prostate cancer: the need for prospective evaluation of short fractionation schemes.

A retrospective review of 173 men with clinical stage B2-C prostate cancer treated by small-volume arc radiotherapy to 5200 cGy in 16 fractions over 4 weeks was undertaken. At 5 years, clinical local failure rates were 14% for stage B2 and 18% for stage C. Five-year survival rates were 81 and 61%, respectively.

Pion radiation for high grade astrocytoma: results of a randomized study.

Purpose: This study attempted to compare within a randomized study the outcome of pion radiation therapy vs. conventional photon irradiation for the treatment of high-grade astrocytomas.

Methods And Materials: Eighty-four patients were randomized to pion therapy (33-34.

Tolerance of nicotinamide and carbogen with radiation therapy for glioblastoma.

Nineteen patients with glioblastoma were treated with nicotinamide and carbogen and radiotherapy. Eight patients did not complete the protocol because of hepatic toxicity from phenytoin/nicotinamide drug interactions, persistent nausea or vomiting with nicotinamide, intolerance of the carbogen breathing apparatus, or other reason. In addition, early radiation neurotoxicity appeared increased.

Early skin response to fractionated doses of pions for determining therapeutic gain factors.

This study concerns the biological effectiveness of fractionated doses of pions on early skin reactions near the implanted tumor, to evaluate the therapeutic gain factors of pions. The C3H mouse limbs bearing microscopical SCCVII tumors were irradiated with pions (9.6-38.

Postoperative radiotherapy for stage pT3 carcinoma of the prostate: improved local control.

Purpose: We determined whether radiotherapy after radical prostatectomy leads to improved results in patients with stage pT3 carcinoma of the prostate.

Materials And Methods: In a prospective nonrandomized study of 203 patients with clinical stage T2 prostate cancer treated with radical prostatectomy 88 underwent surgery alone, 89 received early postoperative radiotherapy generally because of pathological stage T3 disease and 26 received delayed radiotherapy for local recurrence. The disease was stage pT3N0/X in 135 patients.

Radiosensitizing effect of nicotinamide and carbogen combined in fractionated pions or x-rays in SCCVII tumors.

Well-known radiotherapeutic strategies for hypoxic cells include hypoxic radiosensitizers, heavy particles, and fractionated irradiation. This study attempted to obtain the ultimate effectiveness of these strategies by combining nicotinamide plus carbogen (N + C) as a hypoxic radiosensitizer with fractionated pions. In addition, the influence on the N + C effect of X-ray dose rate used as a reference radiation was evaluated.

Biological effectiveness of fractionated dose of pions in microscopic SCCVII tumors: comparison between tumor control dose and tumor growth time assays.

The relative biological effectiveness (RBE) of fractionated pions for tumor growth time (TGT) assay changes with the endpoints, so it is essential to determine the RBE for tumor control dose (TCD) assay. For this purpose, the TCD50 of fractionated pions was compared with that of photons, and the RBEs for TGT and TCD assays were concurrently compared as a function of the effect level. A "convenient" RBE (cRBE) was substituted for the RBE when the comparison was made between similar fractionation schedules with different dose per fraction.

Pions--the potential for therapeutic gain in locally advanced prostate cancer: dose escalation and toxicity studies.

Since 1982, 49 patients with locally advanced carcinoma of the prostate have been treated with pion radiotherapy in tolerance and tumor response studies. The relative biological effectiveness (RBE) was confirmed as 1.5 for both acute and late effects, a figure expected on the basis of animal and human studies.

4-hydroxyandrostenedione--further clinical and extended endocrine observations.

4-Hydroxyandrostenedione (4-OHA) was administered (250 mg intramuscularly 2-weekly) in a phase 2 clinical trial to 20 postmenopausal patients with advanced breast cancer, who had failed other endocrine therapy. Seven out of 18 assessable patients (39%) responded with minimal toxicity. Endocrine studies demonstrated that the drug produced significant initial falls in oestradiol and oestrone levels, but that these levels rose toward pretreatment levels as the study progressed.