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G G Duncan

Publications and source records attributed to G G Duncan.

At least 19 recordsLinked to original sources
PubMed2000

Report on the quality of life analysis from the phase III trial of pion versus photon radiotherapy in locally advanced prostate cancer.

This report examines the quality of life (QOL) of 215 patients entered into a randomised trial between pion and photon radiotherapy for prostate cancer at a single institution. The survival and local control results of the trial were equivalent in both arms. A modification of the Rotterdam Symptom Checklist (RSCL) was used to assess QOL. Global QOL, toxicity and physical scores were found to be worse in pion-treated patients at the end of treatment (P<0.001, P<0.001, and P=0.02 respectively). There are no long-term differences in the QOL of pion- versus photon-treated patients. Sexual function was a concern for patients even at baseline. There was a progressive loss of sexual interest and erectile function. There was a significant impact from hormonal therapy at relapse. Hormonal treatment produced a stepwise significant worsening in global QOL, particularly for physical and psychological domains.

Adenocarcinoma↗
PubMed1999

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. RESULTS: Median follow-up was 42 months (range 2-90). Acute bladder toxicity was worse in the pion arm, p = 0.2, but other acute toxicity did not differ. Late grade 2 toxicity was significantly less in the pion arm (29% at 5 years versus 48%, p = 0.002), but late grade 3 or 4 toxicity did not differ. Clinical local control was not significantly different between treatment arms (64% after 5 years with photons, 56% with pions, p = 0.6). Cause-specific and overall survival also did not differ (p = 0.7). There was a significant delay in time to first failure in the photon arm, largely as a result of decreased biochemical relapse, p = 0.01. A multivariate analysis is presented. CONCLUSION: Pion therapy was well tolerated, with increased acute toxicity and significantly decreased late tissue injury. This contrasts with the late toxicity observed with higher LET particle therapy such as neutron therapy. No improvement in local control with pion therapy was observed.

Adenocarcinoma↗
PubMed1997

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 (33-34.5 Gy pi), or conventional photon irradiation (60 Gy). Entry criteria included astrocytoma (modified Kernohan high Grade 3 or Grade 4), age 18-70, Karnofsky performance status (KPS) > or = 50, ability to start irradiation within 30 days of surgery, unifocal tumor, and treatment volume < 850 cc. The high-dose volume in both arms was computed tomography enhancement plus a 2-cm margin. The study was designed with the power to detect a twofold difference between arms. RESULTS: Eighty-one eligible patients were equally balanced for all known prognostic variables. Pion patients started radiation 7 days earlier on average than photon patients, but other treatment-related variables did not differ. There were no significant differences for either early or late radiation toxicity between treatment arms. Actuarial survival analysis shows no differences in terms of time to local recurrence or overall survival where median survival was 10 months in both arms (p = 0.22). The physician-assessed KPS and patient-assessed quality of life (QOL) measurements were generally maintained within 10 percentage points until shortly before tumor recurrence. There was no apparent difference in the serial KPS or QOL scores between treatment arms. CONCLUSION: In contrast to high linear energy transfer (LET) therapy for central nervous system tumors, such as neutron or neon therapy, the safety of pion therapy, which is of intermediate LET, has been reaffirmed. However, this study has demonstrated no therapeutic gain for pion therapy of glioblastoma.

Adult↗
PubMed1996

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.

Administration, Inhalation↗
PubMed1995

Polymorphic human specific Alu insertions as markers for human identification.

Alu sequences represent the largest family of short interspersed repetitive elements (SINEs) in humans with 500 000 copies per genome. Recently, one Alu subfamily was found to be human specific (HS). We originally described the use of polymorphis HS Alu insertions as a tool in population studies and recently as tools in DNA fingerprinting and forensic analysis. In this report, we will use this simple polymerase chain reaction (PCR) base technique for the detection of HS Alu insertion polymorphisms. We will test the resolving power of this DNA profiling approach in both population genetics and paternity assessment. At the population level, we will describe the genotypic distribution of five polymorphic Alu insertions among 3 populations from the American continent, one of African origin, the other two Amerindians. Insight into their relationships will be provided. At the family level, we will examine one European American family of seven individuals and the same pedigree will also be characterized by way of the two systems currently and widely used to ascertain paternity: PCR-sequence specific oligonucleotide probe hybridization (PCR-SSO) and PCR-restriction fragment length polymorphism (PCR-RFLP) of human leucocyte antigen (HLA) class II molecules, and a standard RFLP protocol used in forensic casework and paternity studies. The importance and strengths of the methods as well as its perspectives for future use in filiation studies will be evaluated.

Forensic Medicine↗
PubMed1992

The treatment of adult supratentorial high grade astrocytomas.

From 1 January, 1982 until 31 December, 1987 260 adult patients were referred to the Cancer Control Agency of B.C. with high grade supratentorial astrocytomas. Multifocal disease on presentation was present in 17 cases (6.5%). Their survival is poor and whole brain radiotherapy is required. All other cases had unifocal disease, but eight did not receive radiotherapy. The 235 cases who received radiotherapy were subject to univariate and multivariate analyses according to extent of surgery, age, Kernohan and WHO grading, Karnofsky performance status, whole brain treatment, partial brain treatment, total dose and neuroret. Age is an extremely important predictor of survival (P approximately equal to 0). The pathologic appearance of glioblastoma (WHO grade) as well as the Karnofsky performance status were also important independent factors in predicting survival (P = 0.016, 0.027 respectively) on Cox multivariate analysis. Dose and neurorets were significant factors only in cases where the performance status was not recorded, suggesting that dose was selected according to the patient's condition and age. In this analysis it was found that localized radiation fields may be used rather than whole brain without jeopardizing survival.

Adult↗