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Dive into the research topics where Dorcas Fulton is active.

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Featured researches published by Dorcas Fulton.


Journal of Clinical Oncology | 2004

Abbreviated Course of Radiation Therapy in Older Patients With Glioblastoma Multiforme: A Prospective Randomized Clinical Trial

Wilson Roa; P. M.A. Brasher; G. Bauman; M. Anthes; E. Bruera; A. Chan; B. Fisher; Dorcas Fulton; Sunil Gulavita; Chunhai Hao; S. Husain; Albert Murtha; Kenneth C. Petruk; D. Stewart; P. Tai; Raul C. Urtasun; J. G. Cairncross; P. Forsyth

PURPOSE To prospectively compare standard radiation therapy (RT) with an abbreviated course of RT in older patients with glioblastoma multiforme (GBM). PATIENTS AND METHODS One hundred patients with GBM, age 60 years or older, were randomly assigned after surgery to receive either standard RT (60 Gy in 30 fractions over 6 weeks) or a shorter course of RT (40 Gy in 15 fractions over 3 weeks). The primary end point was overall survival. The secondary end points were proportionate survival at 6 months, health-related quality of life (HRQoL), and corticosteroid requirement. HRQoL was assessed using the Karnofsky performance status (KPS) and Functional Assessment of Cancer Therapy-Brain (FACT-Br). RESULTS All patients had died at the time of analysis. Overall survival times measured from randomization were similar at 5.1 months for standard RT versus 5.6 months for the shorter course (log-rank test, P =.57). The survival probabilities at 6 months were also similar at 44.7% for standard RT versus 41.7% for the shorter course (lower-bound 95% CI, -13.7). KPS scores varied markedly but were not significantly different between the two groups (Wilcoxon test, P =.63). Low completion rates of the FACT-Br (45%) precluded meaningful comparisons between the two groups. Of patients completing RT as planned, 49% of patients (standard RT) versus 23% required an increase in posttreatment corticosteroid dosage (chi(2) test, P =.02). CONCLUSION There is no difference in survival between patients receiving standard RT or short-course RT. In view of the similar KPS scores, decreased increment in corticosteroid requirement, and reduced treatment time, the abbreviated course of RT seems to be a reasonable treatment option for older patients with GBM.


Annals of Neurology | 1999

Which glioblastoma multiforme patient will become a long‐term survivor? A population‐based study

James N. Scott; N.B. Rewcastle; P.M.A. Brasher; Dorcas Fulton; J.A. MacKinnon; M. Hamilton; J. G. Cairncross; P. Forsyth

In this clinical and histopathological study, the frequency of long‐term glioblastoma multiforme (GBM) survivors (LTGBMSs) was determined in a population‐based study. The Alberta Cancer Registry was used to identify all patients diagnosed with GBM in Alberta between January 1, 1975, and December 31, 1991. Patient charts were reviewed and histology reexamined. LTGBMSs were defined as GBM patients surviving 3 years after diagnosis. Each LTGBMS was compared with 3 age‐, sex‐, and year of diagnosis–matched controls, and patient/treatment or tumor characteristics that predicted long‐term survival were determined. There were 689 GBMs diagnosed in the study period; 15 (2.2%) of these patients survived 3 years. LTGBMSs (average age, 43.5 ± 3.3 years) were significantly younger when compared with all GBM patients (average age, 53.0 ± 0.56 years). LTGBMSs had a higher Karnofsky Performance Status score at diagnosis compared with controls. LTGBMSs were much more likely to have had a gross total resection and adjuvant chemotherapy than control GBM patients. Tumors from LTGBMSs tended to have fewer mitoses and a significantly lower Ki‐67 cellular proliferation index compared with controls. Radiation‐induced dementia was common and disabling in LTGBMSs. In conclusion, conventionally treated GBM patients in an unselected population have a very small chance of long‐term survival. The use of aggressive surgical resection and adjuvant chemotherapy may make long‐term survival more likely in GBM patients if their performance status is high at diagnosis. Ann Neurol 1999;47:183–188


Canadian Journal of Neurological Sciences | 2003

Prophylactic anticonvulsants in patients with brain tumour.

Peter A. Forsyth; Susan A. Weaver; Dorcas Fulton; Penelope M. A. Brasher; Garnette R. Sutherland; Doug Stewart; Neil A. Hagen; Penny Barnes; J. Greg Cairncross; Lisa M. DeAngelis

OBJECTIVE We conducted a clinical trial to determine if prophylactic anticonvulsants in brain tumour patients (without prior seizures) reduced seizure frequency. We stopped accrual at 100 patients on the basis of the interim analysis. METHODS One hundred newly diagnosed brain tumour patients received anticonvulsants (AC Group) or not (No AC Group) in this prospective randomized unblinded study. Sixty patients had metastatic, and 40 had primary brain tumours. Forty-six (46%) patients were randomized to the AC Group and 54 (54%) to the No AC Group. Median follow-up was 5.44 months (range 0.13-30.1 months). RESULTS Seizures occurred in 26 (26%) patients, eleven in the AC Group and 15 in the No AC Group. Seizure-free survivals were not different; at three months 87% of the AC Group and 90% of the No AC Group were seizure-free (log rank test, p = 0.98). Seventy patients died (unrelated to seizures) and survival rates were equivalent in both groups (median survival = 6.8 months versus 5.6 months, respectively; log rank test, p = 0.50). We then terminated accrual at 100 patients because seizure and survival rates were much lower than expected; we would need > or = 900 patients to have a suitably powered study. CONCLUSIONS These data should be used by individuals contemplating a clinical trial to determine if prophylactic anticonvulsants are effective in subsets of brain tumour patients (e.g. only anaplastic astrocytomas). When taken together with the results of a similar randomized trial, prophylactic anticonvulsants are unlikely to be effective or useful in brain tumour patients who have not had a seizure.


Canadian Journal of Neurological Sciences | 1998

Long-term Glioblastoma Multiforme Survivors: a Population-based Study

James N. Scott; N.B. Rewcastle; P.M.A. Brasher; Dorcas Fulton; Neil A. Hagen; J.A. MacKinnon; Garnette R. Sutherland; J. G. Cairncross; Peter Forsyth

BACKGROUND Long-term glioblastoma multiforme survivors (LTGBMS) are uncommon. The frequency which these occur in an unselected population and factors which produce these unusually long survivors are unknown. OBJECTIVES To determine in a population-based study 1) the frequency of LTGBMS in a population and 2) identify which patient, treatment or tumor characteristics would predict which glioblastoma (GBM) patient would become a LTGBMS. METHODS The Alberta Cancer Registry was used to identify all patients diagnosed with GBM in southern Alberta between 1/1/75-12/31/91. Patient charts were reviewed and histology re-examined by a blinded neuropathologist. LTGBMS were defined as GBM patients surviving > or = 3 years after diagnosis. Each LTGBMS was compared to three age-, gender-, and year of diagnosis-matched controls to compare patient, treatment, and tumor factors to GBM patients without long-term survival. RESULTS There were 279 GBMs diagnosed in the study period. Five (1.8%) survived > or = three years (range, 3.2-15.8 years). Seven additional long-term survivors, who carried a diagnosis of GBM, were excluded after neuropathologic review; the most common revised diagnosis was malignant oligodendroglioma. LTGBMS (avg. age = 45 years) were significantly younger when compared to all GBM patients (avg. age = 59 years, p = 0.0001) diagnosed in the study period. LTGBMS had a higher KPS at diagnosis (p = 0.001) compared to controls. Tumors from LTGBMS tended to have fewer mitoses and a lower Ki-67 cellular proliferative index compared to controls. Radiation-induced dementia was common and disabling in LTGBMS. CONCLUSIONS These data highlight the dismal prognosis for GBM patients who have both a short median survival and very small chance (1.8%) of long-term survival. The LTGBMS were younger, had a higher performance status, and their tumors tended to proliferate less rapidly than control GBM patients. When long-term survival does occur it is often accompanied by severe treatment-induced dementia.


Journal of Neuro-oncology | 1996

Phase II study of prolonged oral therapy with etoposide (VP16) for patients with recurrent malignant glioma

Dorcas Fulton; Raul C. Urtasun; Peter Forsyth

SummaryBecause the percentage of dividing cells in malignant glioma is small, cell cycle specific drugs such as VP16 are most effective if given continuously over prolonged periods. In this study, we chose a dose of 50 mg/day to minimize therapy interruptions for myelosuppresion. VP16 was given until the neutrophil count dropped to < 1.0 × 109/L or the platelets fell to < 75 × 109/L and resumed when the counts rose to normal levels. We treated 46 patients with supratentorial malignant glioma (15 anaplastic astrocytoma, 21 glioblastoma multiforme, 9 anaplastic oligodendroglioma, l undifferentiated primary malignant brain tumor) at the time of tumor progression. All had KPS ≥ 70 at study entry. All patients had prior RT,13 with adjuvant nitrosourea. Twenty-four had prior nitrosourea chemotherapy for tumor progression, 7 had no prior chemotherapy. We treated 20 patients with VP16 at first progression and 26 at second or later progression. All patients had CT or MR scans and clinical evaluation every 8 weeks. Median time to tumor progression (TTP) was 8.8 weeks for all evaluable patients, 8.6 weeks for those treated at first progression and 8.4 weeks for those treated at second progression, 9.1 weeks for anaplastic astrocytoma, 7.5 weeks for glioblastoma multiforme and 17.1 weeks for anaplastic oligodendroglioma. There were 8 responses and 11 patients with stable disease for at least 8 weeks (R + SD = 42%). Prolonged low-dose oral VP15 is well tolerated, with minimal myelosuppression. Prolonged low-dose oral VP16 is modestly effective treatment for patients with recurrent malignant glioma and is more effective for anaplastic astrocytoma and anaplastic oligodendroglioma than glioblastoma multiforme.


International Journal of Radiation Oncology Biology Physics | 1984

Misonidazole combined with hyperfractionation in the management of malignant glioma

Dorcas Fulton; Raul C. Urtasun; Kyu H. Shin; Peter H.S. Geggie; H. Thomas; Paul J. Muller; J. Moody; Hilary Tanasichuk; Bruce Mielke; Edward S. Johnson; B. Curry

Multiple daily fractionated radiation therapy (MDF) may be more effective than conventionally fractionated radiation therapy (CF) in the treatment of malignant glioma. The hypoxic cell sensitizer misonidazole (MISO) could be more effective when employed with small fractions of radiation every 4 hours to take advantage of the long half-life of the drug. To evaluate MDF and MDF in combination with MISO, a randomized prospective trial was initiated. Between January 1981, and December 1982, patients with histologically verified astrocytoma with anaplastic foci or glioblastoma multiforme were randomized to CF (5800 cGy, 30 fractions, 6 weeks), MDF (6141 cGy, 69 fractions, 4 1/2 weeks, at 89 cGy every 4 hours 3 times daily) and MDF in combination with MISO (1.25 gm/M2 three times weekly for the first 3 weeks). In January 1983, the CF arm was dropped and a high dose MDF arm added (7120 cGy, 80 fractions, 5 1/2 weeks, at 89 cGy per fraction every 4 hours 3 times daily). CCNU chemotherapy was given at the time of tumor progression. One hundred and twenty-eight patients were evaluated (38 CF, 42 MDF, 37 MDF plus MISO, and 11 high dose MDF). Median survival was 29 weeks for CF, 45 weeks for MDF and 50 weeks for MDF plus MISO. Survival was significantly improved for patients treated with MDF compared to patients treated with CF (p less than .002). The addition of MISO to MDF did not result in further improvement in survival. Acute toxicity was acceptable. No clinically apparent delayed toxicity was observed.


Cancer Chemotherapy and Pharmacology | 1982

Intrathecal cytosine arabinoside for the treatment of meningeal metastases from malignant brain tumors and systemic tumors

Dorcas Fulton; Victor A. Levin; Philip H. Gutin; Michael S. B. Edwards; Margaret L. Seager; Julianna Stewart; Charles B. Wilson

SummaryThirty-two patients with primary or metastatic neoplasms in the ventricular system or subarachnoid space were treated with intrathecal Ara-C. Twenty patients (group I) were treated with single twice-weekly doses; the mean number of doses was 9.7, and the mean total dosage was 165 mg. Six patients received intrathecal Ara-C alone and 14 received concurrent chemotherapy. All four symptomatic patients showed clinical improvement. Malignant cells disappeared from the spinal fluid of six of the 12 patients with positive pretherapy cerebrospinal fluid (CSF) cytology. Two patients were alive with no evidence of recurrence 8 and 16 weeks after beginning therapy, two patients died without demonstrating evidence of recurrence 8 weeks and 9 weeks after starting therapy, 12 patients had recurrences an average of 13 weeks after beginning treatment, and four patients refused further investigation or treatment and died of disease after 6–52 weeks.Pharmacokinetic studies were performed in eight patients. For five patients who received 12 mg Ara-C by injection into an SC-implanted reservior connected to the ventricular system, the CSF disappearance curve was biphasic with half-times of 30 min and 3.5 h.Based on the results of the pharmacokinetic study, an additional 12 patients (group II) were treated on three consecutive days weekly. The mean number of doses was 9.7 and the mean total dosage was 189 mg. Three patients received intrathecal Ara-C alone and nine received concurrent chemotherapy. One of the five symptomatic patients showed clinical improvement. Malignant cells disappeared from the spinal fluid of two of the four patients with positive pretherapy CSF cytology. Four patients were alive with no evidence of recurrence 3–26 weeks after beginning therapy, two patients died within 10 days of beginning treatment without formal re-evaluation, four patients demonstrated progression of tumor an average of 7 weeks after beginning treatment, and two patients changed to another form of therapy because of persistent CSF abnormalities, although there was no radiographic evidence of tumor progression.There were no clear differences in response between group I and group II; however, the groups were not comparable with respect to pathological diagnosis.Intrathecal Ara-C is a promising and relatively safe treatment for malignant disease in the subarachnoid space. Further studies are needed to determine the optimum dose and administration schedule in combination with other intrathecal therapies that may be more active against noncycling G0 cells.


Annals of Oncology | 1999

Is primary CNS lymphoma really becoming more common? A population-based study of incidence, clinicopathological features and outcomes in Alberta from 1975 to 1996

D. Hao; L. M. DiFrancesco; Penny M. A. Brasher; C. deMetz; Dorcas Fulton; Lisa M. DeAngelis; P. A. J. Forsyth

BACKGROUND The incidence of primary CNS lymphoma (PCNSL) is believed to be increasing in immunocompetent patients but this may not be universally true. The objective of this study was to determine in a population if the incidence of PCNSL is increasing, if the histologic subtypes are changing, and to describe the clinicopathologic and outcome characteristics of PCNSL. PATIENTS AND METHODS We identified all Alberta residents with a histologic diagnosis of PCNSL from 1 January 1975 to 31 December 1996 using the Alberta Cancer Registry. Annual age-standardized incidence rates (ASIR), clinicopathologic and outcome characteristics were determined. RESULTS There were 50 immunocompetent PCNSL patients; the median age was 64 and 30 were male. Their median survival was 10.15 months. Histology was available for review in 37 (74%) patients: 19 (51%) were diffuse large cell, 16 (43%) were immunoblastic and 2 (5%) were unclassifiable malignant lymphomas. The ASIR ranged from 0.178-1.631/10(6) and no change in ASIR was found (test for trend, P = 0.26) for gender or age. The ASIR of malignant gliomas did not change either but increased for all other non-Hodgkins lymphoma (94.95-138.7610(6); test for trend, P = 0.0001) The number of brain biopsies increased from 1979-1985 (test for trend, P < 0.0001) but remained stable from 1986-1996 (test for trend, P = 0.99). CONCLUSIONS Unlike several other populations, PCNSL is not becoming significantly more common in Alberta. If this difference is real (i.e., not due to differences in cancer registry coding practices etc.) comparisons between Albertans and other populations in whom the incidence is rising may provide clues regarding the etiology of PCNSL.


Cancer | 1983

Improvement in survival produced by sequential therapies in the treatment of recurrent medulloblastoma

Victor A. Levin; Pamela Vestnys; Michael S. B. Edwards; William M. Wara; Dorcas Fulton; Geoffrey R. Barger; Margaret L. Seager; Charles B. Wilson

Thirty‐six patients with recurrent medulloblastoma were treated with various combination chemotherapy protocols after initial treatment (usually irradiation) failed. Use of systemic chemotherapy was limited by depressed bone marrow reserves secondary to previous craniospinal irradiation. Intraventricular and intrathecal therapies included cytosine arabinoside (Ara‐C), methotrexate, and thio‐tepa given as single agents. Major systemic agents used alone or in combination included CCNU, procarbazine, vincristine, and the hexitol epoxides. Patients were reirradiated with or without misonidazole when there was definite tumor progression after all other therapies failed and/or because myelosuppression was so severe that further chemotherapy was not possible. Sequential systemic or intrathecal chemotherapy and reirradiation produced median survivals of two years and 25% quartile survivals of 2.9 years. The prognosis for patients harboring recurrent medulloblastoma has improved considerably over the years because of the therapeutic approaches reported here.


International Journal of Radiation Oncology Biology Physics | 1992

RADIOSENSITIVITY TESTING OF HUMAN PRIMARY BRAIN TUMOR SPECIMENS

M. Joan Allalunis-Turner; Geraldine M. Barron; Rufus S. Day; Dorcas Fulton; Raul C. Urtasun

The inherent radiosensitivity of early passage cells derived from 22 patients with tumors of glial origin has been determined using a clonogenic assay system. The mean (+/- SD) surviving fraction at 2 Gy was 0.37 +/- 0.22 (range = 0.02-0.87). No correlation between inherent radiosensitivity and tumor cell plating efficiency or intracellular glutathione was observed. Tumor cells that were both resistant to nitrosoureas and expressed the Mer+ phenotype did not differ significantly in their radiosensitivity as compared to cells that were repair deficient (Mer-) and sensitive to nitrosoureas. Initial clinical follow-up suggests that factors in addition to inherent tumor cell radiosensitivity, such as performance status and age, continue to be the most important determinants of the response of patients with primary brain tumors to radiotherapy.

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Wilson Roa

Cross Cancer Institute

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Victor A. Levin

University of Texas MD Anderson Cancer Center

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Samir Patel

Cross Cancer Institute

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