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P Genest

Publications and source records attributed to P Genest.

At least 19 recordsLinked to original sources
PubMed2006

The preferred treatment for stage I seminoma: a survey of Canadian radiation oncologists.

AIMS: To evaluate the preferences of radiation oncologists for managing stage I seminoma. MATERIALS AND METHODS: An electronic survey evaluating the management of stage I seminoma patients was sent to Canadian radiation oncologists to determine their treatment recommendations and preferences. RESULTS: The survey completion rate was 74% among eligible respondents (78/105). Most (56%) felt that surveillance was the preferred treatment for patients, whereas 31% thought that adjuvant radiotherapy was best, 1% chose adjuvant chemotherapy as being the preferred option and 12% were unsure. Most would choose the same treatment for themselves if they were diagnosed with stage I seminoma. A previously published survey found that most respondents considered radiotherapy as the best option. CONCLUSIONS: Most Canadian radiation oncologists now favour surveillance for most stage I seminoma patients.

Canada↗
PubMed2003

A consensus development approach to define national research priorities in bone metastases: proceedings from NCIC CTG workshop.

AIMS: A 1-day workshop was conducted to gather interested Canadian radiation oncologists to identify priority research questions that could be answered through clinical trials under the auspices of the National Cancer Institute of Canada--Clinical Trials Group (NCIC-CTG) Symptom Control committee. MATERIALS AND METHODS: In preparation for the workshop, a survey of Canadian radiation oncologists resulted in four research areas in symptom control, including radiation-induced mucosal reactions, fatigue, radiotherapy for brain metastases and radiotherapy for bone metastases. The first half of the workshop consisted of plenary sessions where the research setting and perspective was defined for each area. This was followed by deliberations by a subgroup of researchers with special interest in the topic area. The bone-metastases subgroup deliberated the clinical context, the scientific merits and the required methodology of research questions related to the role of radiotherapy in early treatment of bone metastases, the role of re-irradiation, the role of systemic radiotherapy and patient selection for different fractionation schedules. A list of prioritised clinical studies was proposed. RESULTS: The question of single vs multi-fraction re-irradiation for symptomatic bone metastases was identified as most pertinent to the Canadian radiation oncologists present. A multi-centre, international intergroup study is undergoing protocol development. Other study concepts, such as an alternative dose-schedule of 17 Gy/2 fractions/1 week for intermediate-prognosis patients, and early referral for radiation oncologist assessment of early or mildly symptomatic bone metastases for good-prognosis patients, require further methodological development before a clinical trial can be proposed. CONCLUSION: An NCIC-CTG workshop provided an update on current evidence-based knowledge in palliative radiotherapy for bone metastases. New trial concepts were discussed among practitioners and clinical investigators to promote dialogue and collaboration. The proposal of an international intergroup randomised trial of single vs multiple fraction re-irradiation for painful bone metastases received the most support among participants.

Bone Neoplasms↗
PubMed2002

Outpatient total body irradiation as a component of a comprehensive outpatient transplant program.

Outpatient total body irradiation (TBI) as part of a comprehensive outpatient transplant program was delivered to 142 of 167 (85%) consecutive patients receiving TBI-based conditioning therapy. Outpatients received either a single fraction of 500 cGy (110 patients) or 1200 cGy in six fractions over 3 days (32 patients). Patients were assessed daily and were administered oral ondansetron and dexamethasone for prophylaxis of nausea and vomiting as well as i.v. hydration. Accommodation during outpatient TBI-based conditioning was either the patient's home if within 30 min of the hospital, a hotel on the hospital grounds or on a closed hospital ward. None of the 142 patients required admission to the inpatient program during their TBI. There was no difference in 100-day mortality between those receiving TBI as an outpatient (9%) vs as an inpatient (16%). Of four deaths occurring within the first 14 days post transplant, none could be attributed to receiving TBI as an outpatient. Two hundred and six inpatient days were saved through the delivery of outpatient TBI. A comprehensive outpatient program, appropriate patient selection, daily hydration, the use of prophylactic 5HT3 antagonist anti-emetic therapy all contribute to the safe delivery of outpatient TBI.

Adolescent↗
PubMed1998

A randomized trial of granulocyte colony-stimulating factor (Neupogen) starting day 1 vs day 7 post-autologous stem cell transplantation.

The purpose of the study was to evaluate the effect of delayed granulocyte colony-stimulating factor (G-CSF) use on hematopoietic recovery post-autologous peripheral blood progenitor cell (PBPC) transplantation. Patients were randomized to begin G-CSF on day +1 or day +7 post transplantation. Thirty-seven patients with lymphoma or myeloma undergoing high-dose therapy and autologous PBPC rescue were randomized to daily subcutaneous G-CSF beginning on day +1 or day +7 post-transplant. Patients < or =70 kg received 300 microg/day and >70 kg 480 microg/day. All patients were reinfused with PBPCs with a CD34+ cell count >2.0 x 10(6)/kg. Baseline characteristics of age, sex and CD34+ cell count were similar between the two arms, the median CD34+ cell count being 5.87 x 10(6)/kg in the day +1 group and 7.70 x 10(6)/kg in the day +7 group (P=0.7). The median time to reach a neutrophil count of >0.5 x 10(9)/l was 9 days in the day +1 arm and 10 days in the day +7 arm, a difference which was not statistically significant (P=0.68). Similarly, there was no difference in median days to platelet recovery >20000 x 10(9)/l, which was 10 days in the day +1 arm and 11 days in the day +7 arm (P=0.83). There was also no significant difference in the median duration of febrile neutropenia (4 vs 6 days; P=0.7), intravenous antibiotic use (7 vs 8 days; P=0.54) or median number of red blood cell transfusions (4 vs 7 units; P=0.82) between the two arms. Median length of hospital stay was 11 days post-PBPC reinfusion in both groups. The median number of G-CSF injections used was 8 in the day +1 group and 3 in the day +7 group (P < 0.0001). There is no significant difference in time to neutrophil or platelet recovery when G-CSF is initiated on day +7 compared to day +1 post-autologous PBPC transplantation. There is also no difference in number of febrile neutropenic or antibiotic days, number of red blood cell transfusions or length of hospital stay. The number of doses of G-CSF used per transplant is significantly reduced with delayed initiation, resulting in a significant reduction in drug costs. For patients with an adequately mobilized PBPC graft, the initiation of G-CSF can be delayed until day +7 post-PBPC reinfusion.

Adult↗
PubMed1995

Interstitial brachytherapy for penile carcinoma: an alternative to amputation.

From 1987 to 1994, 15 patients with penile saquamous cell carcinoma were referred to the Ottawa Regional Cancer Centre. Seven had already been managed surgically. The other eight were treated with interstitial implantation. Mean age was 58 years (range 39-80). Two patients had previous incomplete local excision and six had biopsy only, with tumor from 1.5 to 4 cm in diameter. Six tumors were located on the glans, one on the corona and one at the base. All were clinically node negative. Six patients were implanted using a rigid technique with a fixed array of steel needles in pre-drilled plexiglass templates, and two with flexible nylon tubing. Implants were manually afterloaded with Iridium-192 wire. The prescribed dose of 60-65 Gy was delivered in 2.5-5.5 days. Local tumor control is 100% at a mean follow-up of 37 months (range 6-64). One patient died of metastases at 15 months with the primary controlled. The remaining seven patients are alive without evidence of disease. Six who were sexually active, continue to be so. One patient has a urethral stricture requiring dilatations. Cosmesis is generally good: mild to moderate hypopigmentation, telangiectasia and fibrosis may develop at the implant site. Intersititial brachytherapy for T1 or minimally invasive T2 penile squamous cell cercinoma up to 4 cm in diameter provides excellent local control with preservation of function and is a viable alternative to amputation.

Journal Article↗
PubMed1994

A pilot study of intra-arterial carboplatin in patients with recurrent carcinoma of the cervix, postradiation.

Twelve patients with recurrent squamous cell carcinoma of the cervix restricted to the pelvis were treated with intra-arterial infusion of carboplatin. The initial carboplatin dose was 300 mg/m2, every 4 weeks, and the dose was escalated to 450 mg/m2. Myelosuppression was the dose-limiting toxicity at the 450 mg/m2 dose. One patient died of treatment-related febrile neutropenia at that dose level. Two patients having received one cycle at 300 mg/m2 suffered grade 3 peripheral paresthesia. There were no objective responses but five patients had a subjective improvement of pain and performance status.

Adult↗
PubMed1994

A translating-bed technique for total-body irradiation.

Total-body irradiation (TBI) is a therapy modality that is being used with increasing frequency, in conjunction with chemotherapy, for patients undergoing bone-marrow transplantation. At the Ottawa Regional Cancer Centre a technique has been developed for the delivery of TBI to patients prior to bone-marrow transplantation. In this technique patients are treated on a mobile couch at approximately 195 cm SSD with a field size of 66.5 cm wide by 57 cm long. A computer-controlled stepping motor drives the patient couch at a user-selectable speed. The total dose delivered to the patient is a function of couch velocity, field size and patient separation. Treatment times are of the order of 10 min for each of the anterior and posterior fields for a 400 cGy fraction. It has been found that the conventional central axis tissue maximum ratio (TMR) and percentage depth dose (PDD) functions are not appropriate for describing dose delivered during dynamic treatment. To this end we have developed dynamic TMR and PDD functions. Extensive measurements have been performed in an anthropomorphic water phantom to determine the dose distributions in three dimensions and the efficacy of polymethyl methacrylate (PMMA) beam spoilers as a replacement for anterior and lateral bolus. It has been found that 2.4 cm PMMA spoilers do provide full skin dose and negate the requirement for lateral bolus. This TBI procedure is simple, rapid and appears to be well tolerated by the patients. 55 patients have been treated since the introduction of this technique in 1991.

Bone Marrow Transplantation↗
PubMed1993

Phase II study of lonidamine plus radiotherapy in the treatment of brain metastases.

Twenty-nine patients received the cytotoxic radiosensitizing agent lonidamine before, during, and after cranial irradiation for brain metastases. One patient was ineligible (meningioma). In 28 eligible patients, median survival was 29 weeks (range, 2 to > 220 weeks). Nine patients (32%) survived > 1 year and 3 (11%) survived > 2 years. The major toxic effects of lonidamine were myalgias, nausea and vomiting, somnolence, and ototoxicity. There was no evidence that radiation skin toxicity or cerebral toxicity was increased by the addition of lonidamine. None of the patients experienced shrinkage of their extracerebral disease on lonidamine. Median survival duration in this study was at the upper limit of that reported in the literature for radiation alone, and the proportion of 2 year survivors was also higher than usual for radiation alone. Hence, further studies may be warranted.

Adult↗
PubMed1993

Brachytherapy of neck metastases.

Brachytherapy with iridium 192 was used in 20 patients with recurrent or persistent neck metastases from a primary head and neck carcinoma. Nine patients had intra-operative brachytherapy in combination with a neck dissection. Three patients had an implant as a boost following external beam radiotherapy. Eight patients were treated by brachytherapy alone for unresectable neck recurrence ranging from 5 to 10 cm in diameter. Nineteen patients were evaluable for neck control: 15 patients had complete clearance of tumor and 13 patients were controlled at time of death or last follow-up. There were few complications from treatment. Five patients are alive at 5, 14, 16, 22, and 27 months post-implant with two patients having developed a second primary. Seven patients died from distant metastases, four from regional disease and four from intercurrent illness. Indications are summarized for this frequently forgotten but useful last option for patients with persistent or recurrent neck metastases.

Aged↗
PubMed1990

Gallstone ileus masquerading as recurrent carcinoma of the ovary.

A case of gallstone ileus in a patient with carcinoma of the ovary is presented. A 78-year-old female with stage III carcinoma of the ovary underwent optimal debulking surgery followed by six courses of chemotherapy and a microscopically positive second-look laparotomy. She was treated by whole-abdomen pelvic radiation. She then developed progressive nausea, vomiting, abdominal distension, and eventually complete small bowel obstruction. The diagnosis of gallstone ileus was made preoperatively based on the radiological findings. The pathophysiology of gallstone ileus is discussed in the differential diagnosis of patients treated for carcinoma of the ovary.

Aged↗
PubMed1989

Obstructive ureteropathy following radiation therapy for carcinoma of the cervix.

Between January 1959 and December 1986, 10 of 328 patients (3%) treated with curative intent using primary radiation therapy for carcinoma of the cervix developed obstructive ureteropathy due to fibrosis. The mean age of the patients with obstructive ureteropathy was 45 years and the median time to obstruction was 26 months. The obstruction was unilateral in 8 cases and involved the parametrial portion of the ureter in at least 5 cases. No predisposing risk factor was found to be associated with the development of obstructive ureteropathy. After corrective surgery, renal function remained normal in 8 patients, and resolution of the hydronephrosis occurred in 4 patients.

Adenocarcinoma↗
PubMed1989

Intraarterial cisplatin and concurrent radiation for locally advanced bladder cancer.

Between 1983 and 1987 25 patients with invasive bladder cancer (16 stage tumor 3 (T3) and nine stage T4) were treated with intraarterial cisplatin and concurrent radical radiation (20/25) or intraarterial cisplatin, concurrent preoperative radiation, and cystectomy (5/25). One patient died from treatment-related toxicity. Other toxicities have been what one would expect from the individual treatment modalities except for a sensory sacral root neuropathy in 11 of 24 (46%) patients. Twenty-three of 24 (96%) patients achieved a complete response (CR) and the projected actuarial 2-year survival is 90%. Only one of the 23 complete responders has had an invasive local recurrence. The excellent complete local response and survival rates achieved warrant further study of the combination of intraarterial cisplatin and radiation as a bladder-preserving strategy.

Aged↗
PubMed1988

Brain metastases with an unknown primary: a clinical perspective.

A review of 43 patients with cerebral metastases, an unknown primary, and no other sites of metastases is presented. 27/43 (62.7%) had solitary metastases and 37.2% (16/43) had multiple metastases. Surgical treatment involved complete resection in 30.2%, subtotal resection in 37.2% and biopsy alone or no surgical procedure in the remainder. 39/43 patients underwent whole brain irradiation with the majority receiving 3,000-4,000 rads/10-20 fractions. Overall survival was 52% at six months and 20% at one year, and was significantly better in patients with solitary as opposed to multiple metastases (p less than 0.03). A failure analysis including autopsy data demonstrates that (28/41) 68.3% of patients died of progressive intracranial disease without extracerebral metastases. Implications for treatment strategies are discussed.

Actuarial Analysis↗
PubMed1988

Does parasternal irradiation reduce thoracic vertebral metastases in breast cancer?

A review of 197 patients with bone metastases from breast carcinoma was undertaken to assess the effect of adjuvant parasternal irradiation on the distribution of those metastases. A total of 128 patients (Group I) received radiation. The control group consisted of 69 patients (Group II) who did not receive adjuvant radiation. The dose absorbed by the mid-thoracic vertebrae (T3 to T8) varied from 10 Gy in 3 weeks to 20 Gy in 4 weeks. The distribution of bone metastases was analyzed at the initial development in the 197 patients. Repeat assessments (X ray/scans) were available for analysis in 132 patients. Patients in Group I had less metastases from T3 to T8: 37/128 (29%), vs 30/69 (43.5%) for patients in Group II: (chi 2 = 3.62; p less than 0.10). For the 132 patients with serial assessments, the difference at last evaluation was more significant: 45/86 (52%) in Group I, vs 36/46 (78%) in Group II: (chi 2 = 7.44; p less than 0.01). The data shows that patients receiving low-dose exit beam irradiation from the parasternal field have fewer mid-thoracic bone metastases. Potential implications are discussed.

Breast Neoplasms↗