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D I Hodson

Publications and source records attributed to D I Hodson.

At least 19 recordsLinked to original sources
PubMed2006

Explaining socioeconomic status effects in laryngeal cancer.

INTRODUCTION: People with lower socioeconomic status (SES) experience shorter survival times after a cancer diagnosis for many disease sites. We determined whether area-level SES was associated with the outcomes: cause-specific survival and local-regional failure in laryngeal cancer in Ontario, Canada. When we found an association we sought explanations that might be related to access to care including age, sex, rural residence, tumor stage, lymph node status, use of diagnostic imaging, treatment type, percentage of prescribed radiotherapy delivered, number of radiotherapy interruption days, treatment waiting time, and treating cancer center. MATERIALS AND METHODS: The study population consisted of 661 glottic and 495 supraglottic stage-stratified randomly-sampled patients identified using the Ontario Cancer Registry. Area-level SES quintiles were assigned using adjusted median household income from the Canadian Census. Other data were collected from patient charts. Explanations for SES effects were determined by measuring whether the effect moved toward the null value by at least 10% when an access indicator was added to a the model. RESULTS: Socioeconomic status was not related to either outcome for those with supraglottic cancer, but an association was present in glottic cancer. With the highest socioeconomic status quintile as the referent group, the relative risks for patients in the lowest socioeconomic quintile were 2.75 (95% CI 1.48, 5.12) for cause-specific survival and 1.90 (95% CI 1.24, 2.93) for local-regional failure. Disease stage as measured by T-category explained between 3% and 23% of these socioeconomic effects. None of the other access indicators met our 10% change criterion. CONCLUSION: We question why people in lower socioeconomic quintiles were not diagnosed earlier in the disease progression. Having ruled out several variables that may be related to access to care, additional biologic and social variables should be examined to further understand socioeconomic status effects.

Adult↗
PubMed2003

Phase III quality-of-life study results: impact on patients' quality of life to reducing xerostomia after radiotherapy for head-and-neck cancer--RTOG 97-09.

PURPOSE: To determine whether prevention of hyposalivation after curative radiotherapy (RT) to the head and neck improves patients' quality of life (QOL). METHODS AND MATERIALS: Patients were to receive at least 50 Gy to 50% of the volume of the major salivary glands, provide unstimulated and stimulated saliva samples, and complete the University of Washington head-and-neck QOL tool before RT and 3 and 6 months after RT. Patients were randomized to receive pilocarpine 5 mg or placebo q.i.d. RESULTS: A total of 249 patients was randomized between March 1998 and January 2000. Of these, 214 were eligible for QOL analysis. Patients were evenly distributed between arms by race, gender, tobacco use, tumor site, T stage (50% T2-T3), and salivary function. A Karnofsky performance status of 90% was more common in the pilocarpine arm. Twenty percent of the patients on the pilocarpine arm and 29% of the patients on the placebo arm were taking nutritional supplements. The placebo arm patients had greater mouth pain and chewing difficulties. Compliance for the QOL tool at 3 and 6 months was 65% and 50%, respectively. Despite statistically significant (p = 0.047 and p = 0.049, respectively) preservation of salivary function in the pilocarpine arm, patients on the pilocarpine arm reported difficulties with swallowing (75%), activity (80%), hyposalivation (64%), and taste (81%). No difference was noted between arms at 3 months in mucositis scores, with both arms demonstrating increased requirement for oral nutrients. CONCLUSION: Objective prevention of hyposalivation did not affect patients' assessment of salivary function or QOL because of the greater impact mucositis plays in QOL after RT.

Female↗
PubMed2003

Radiotherapy patterns of practice: T1N0 glottic cancer in Ontario, Canada.

AIMS: To describe the variation in the delivery of radiation therapy to patients with T1N0 glottic cancer who were diagnosed in Ontario, Canada, between 1982 and 1995. MATERIALS AND METHODS: The patient population consisted of a random sample of 461 patients treated with curative intent from the nine cancer centres that administer radiation therapy in the province. Abstracted variables included prescribed dose (Gy) and fractionation (f), beam energy and arrangement, set-up, field size, beam modifiers, positioning and treatment interruptions. RESULTS: Thirteen prescribed dose-fractionation schemes (> or = four cases each) were identified, including 50.0-53.0 Gy/20 f (54.5%), 55.0-61.0 Gy/25 f (30.3%), and 60.0-66.0 Gy/30-33 f (7.7%). All regimens used one fraction per day, 5 days per week. An isocentric set-up was used (94.3%), with megavoltage (MV) beam energies of Cobalt-60 (87.9%), 6 MV (6.1%) and 4 MV (6.1%). A lateral parallel-opposed pair of beams was the predominant technique (76.4%) versus an anterior oblique pair (17.2%) or angle-down pair (caudally directed fields to achieve shoulder clearance, 5.7%). Wedging (96.3%) and bolus (11.8%) were used as beam-modifying devices. Predominant field-width dimensions were 5.0-6.0 cm (43.4%) and 6.5-7.0 cm (43.1%), and field length dimensions were 5.0-6.0 cm (49.5%) and 6.5-7.0 cm (35.0%). Head, neck or chin immobilisation was used in 86.9% of the cases, with 94.6% of these being custom-made. We found that radiotherapy practice was stable over time, except for a trend of increasing field size and increasing use of immobilisation. In contrast, we found practice variations among the province's cancer centres. On the basis of our findings, we defined a predominant technical practice consisting of Cobalt-60 (reflecting machine availability during the period of the study), an isocentric set-up, a lateral parallel-opposed pair technique with wedging, and supine-head neutral positioning with custom immobilisation. Forty-two per cent of the cases had one or more components of treatment that differed from this definition. CONCLUSIONS: Description of practice variation can provoke discussion about unrecognised differences in practice policies, perhaps identifying the need for better evidence, treatment guidelines, or both.

Canada↗
PubMed2001

The role of computed tomography in the T classification of laryngeal carcinoma.

BACKGROUND: The objectives of this study were 1) to describe patterns of use of computed tomography (CT) in laryngeal carcinoma, and 2) to characterize the contribution of CT to the T classification of laryngeal carcinoma. METHODS: The study population comprised 1195 patients with laryngeal carcinoma diagnosed from 1982 through 1995 chosen randomly from the Ontario provincial cancer registry. A chart review was conducted to obtain data on each case. Patient-related, tumor-related, and health-system-related factors were analyzed to identify factors associated with the use of CT. Descriptions of clinical exams and CT reports were reviewed to see how CT information modified T classification. Actuarial local control and cause specific survival curves were plotted by clinical T classification without and with CT to evaluate stage migration. The percentage of the variance in outcome explained by T classification in a Cox analysis was used to evaluate whether the prognostic accuracy of T classification was improved with the use of information from CT. RESULTS: Patients with glottic (20.1%) and supraglottic (41.7%) carcinoma underwent CT. The use of CT increased over time in glottic and supraglottic carcinoma combined from 17.2% in 1982-5 to 33.9% in 1991-5. Computed tomography was used less often in older patients with a 16% (95% confidence interval, 5-27%) decrease in the odds of having CT with each 10-year age increment. Computed tomography use varied considerably across the cancer center regions in Ontario. Computed tomography altered the T classification in 20.2% of those patients who had CT, with most being "upstages." Stage migration due to CT was demonstrated. Using information from CT in the assignment of T classification for 27.8% of this study population did not make a significant contribution to the ability of T classification to predict outcome over the entire group. CONCLUSIONS: There is large variation in the use of CT among different age groups and regions. The ability to compare outcomes by stage across geographic areas is compromised when the use of CT varies.

Analysis of Variance↗
PubMed2001

Choosing a concomitant chemotherapy and radiotherapy regimen for squamous cell head and neck cancer: A systematic review of the published literature with subgroup analysis.

BACKGROUND: A systematic review was conducted to develop clinical recommendations for concomitant chemotherapy (CT) and radiotherapy (RT) in patients with locally advanced squamous cell head and neck cancer (SCHNC). METHODS: Results of published randomized controlled trials (RCTs) were pooled using Meta-analyst(0.988) software. RESULTS: A pooled analysis of 18 RCTs (20 comparisons) involving 3,192 patients detected a reduction in mortality for concomitant therapy compared with RT alone (odds ratio [OR], 0.62; 95% confidence interval [CI], 0.52-0.74; relative risk, 0.83; risk reduction, 11%; p < .00001). Platinum-based regimens involving 1,514 patients from nine trials (10 comparisons) were most effective (OR, 0.57; 95% CI, 0.46-0.71; p < .00001; risk reduction, 12%). Concomitant therapy produced more acute adverse effects than RT alone. CONCLUSION: Platinum-based concomitant CT and RT is superior to conventional RT alone in improving survival in locally advanced SCHNC. Subgroup analyses can be used to help in choosing the most appropriate concomitant regimen.

Carcinoma, Squamous Cell↗
PubMed2001

Glottic cancer in Ontario, Canada and the SEER areas of the United States. Do different management philosophies produce different outcome profiles?

We compared the management and outcome of glottic cancer in Ontario, Canada to that in the Surveillance, Epidemiology and End Results (SEER) Program areas in the United States to determine whether the greater use of primary radiotherapy with surgery reserved for salvage in Ontario was associated with similar survival and better larynx retention rates than the U.S. approach where primary surgery is used more often. Electronic, clinical and hospital data were linked to cancer registry data and supplemented by chart review where necessary. Initial treatment and survival in patients diagnosed in the SEER areas from 1988 through 1994 were compared to patients from Ontario diagnosed from 1982 through 1995. Actuarial laryngectomy rates were compared for patients over 65 at diagnosis in the two regions. Analyses were conducted over all cases and stratified by disease stage. In localized disease (T1 or T2), conservative treatment was the most common initial treatment in both regions, although total laryngectomy was used more often in SEER than Ontario (6.2% vs. 0.2%, respectively, P <.001). In advanced disease (T3 or T4), total laryngectomy was more commonly used as initial treatment in SEER (62.9% vs. 21.0% in Ontario, P < or =.001). Over all cases, the relative survival rate was 80% in Ontario at 5 years compared to 78% in SEER (P =.33). In localized disease, the relative survival rates were 4 to 5% higher in Ontario from the second year on, while in advanced disease 2 to 3% higher rates in SEER did not approach statistical significance. Actuarial laryngectomy rates at 3 years differed between the two regions, with a 4% higher rate in SEER (P =.01). In localized disease, 12.6% of Ontario patients had a laryngectomy by 3 years postdiagnosis compared to 17.9% in SEER (P =.05). In advanced disease, the rates were 63.3% and 79.2%, respectively (P =.07). There are large differences in the management of glottic cancer between the SEER areas of the U.S. and Ontario and no evidence that a policy emphasizing radiotherapy with surgery reserved for salvage is associated with worse survival. Ultimate laryngectomy rates are lower in Ontario for localized disease and may be lower for advanced disease. Conservation treatment should be used for localized disease while the treatment decision in advanced disease may be especially sensitive to patient values for voice retention versus initial cure.

Aged↗
PubMed1998

Progress of clinical oncology guidelines development using the Practice Guidelines Development Cycle: the role of practitioner feedback.

PURPOSE: To present an update on the development of oncology practice guidelines (PGs) using the Practice Guidelines Development Cycle (Cycle), and to present the results of surveys of oncologists on the first 10 guidelines from the Cancer Care Ontario Practice Guidelines Initiative. METHODS: Practitioners' opinions about guidelines in development were sought using a mail survey method with systematic follow-up. Practitioners were identified by cancer center representatives. Survey packages included evidence-based recommendations (EBRs) and a one-page, nine-item feedback questionnaire. Data were collected between February 1995 and February 1996. RESULTS: Nine hundred fourteen surveys that pertained to 10 guidelines were mailed to 423 practitioners in Ontario. Practitioners included 112 medical oncologists/hematologists, 34 radiation oncologists, 195 surgeons, and 82 practitioners from other medical specialities. One hundred practitioners were located in cancer centers and 323 had community-based practices. The overall response rate by practitioner was 72% and by survey questionnaire, 70%. For the five questionnaire items that assessed guideline quality, approval ratings ranged from 86% to 92%. For the 10 recommendations, 77% ( 63% to 82%) of respondents agreed that the EBR could be approved as a PG. Response and approval rates were consistent across medical specialities and locations of practice. CONCLUSION: The process of obtaining practitioner feedback in the development of PGs is both feasible and useful. The high response rates to the survey indicate that it is possible to obtain broad participation in evidence-based guidelines development throughout Ontario. The changes made to the EBRs in response to feedback suggest that practitioners' opinions can be valuable in shaping evidence-based guidelines.

Evidence-Based Medicine↗
PubMed1996

The role of palliative radiotherapy in advanced head and neck cancer.

The role of radiotherapy in the palliation of patients with advanced cancer of the head and neck is not clear. Several distinctive characteristics of advanced head and neck cancer contribute to the complexities in the choice of appropriate palliative management strategies. Palliative treatment may be the appropriate management for a proportion of patients with advanced disease, but the current stage groupings of head and neck cancer are not sufficient for use in the reliable identification of such a patient group. Controversy arises because of the difficulties in distinguishing patients who should be offered conventional treatment with curative intent from those appropriate for treatment with palliative intent. A structured review of the cancer and quality of life literature identified 298 references pertaining to palliative radiotherapy in head and neck cancer, 26 of which met the criteria for inclusion in this review. An expert panel discussed the literature, and concluded that insufficient information precluded estimations of the frequency, degree of, or duration of symptomatic relief that radiation offered to those patients not cured of their disease. Moreover, the currently available literature does not address the toxicity or appropriate dose and fractionation of palliative radiotherapy in this setting. Further studies are necessary to evaluate clinical endpoints appropriate to the use of radiotherapy in the palliative management of patients with advanced head and neck cancer. Studies are also needed to refine the current clinical classification of patients, allowing the identification of patients suitable for palliative management.

Clinical Trials as Topic↗
PubMed1994

Prognosis with newly diagnosed mycosis fungoides after total skin electron radiation of 30 or 35 GY.

PURPOSE: To determine the prognosis of new patients with T1-4N0-1B0M0 mycosis fungoides treated with total skin electron beam radiation. METHODS AND MATERIALS: 25 consecutive patients received 30 Gy with 3 or 4 MeV electrons in 1977-1980; 121 received 35 Gy with 4 MeV in 1980-1992. Response rates, relapse-free survival, and overall and cause-specific survivals were assessed by explicit criteria. The relationships of T, N, gender, age, and radiation technique to prognosis were investigated by regression statistics. RESULTS: The average age was 55 years and the male:female ratio was 1:4. Forty-four percent were T1N0 and 34% were T2N0. The overall complete response rate was 82%, and lower T status, more radiation, and female gender were independently and positively associated with response. Median follow-up was 5.2 years. T1 patients who entered remission had a higher relapse-free survival compared to T2 through T4 patients. Thirty-four percent of T1 patients remained relapse-free at 6 years, compared to fewer than 20% of T2-4 patients. For all 146 patients the median overall survival was not reached at 15 years. Only 8 of 29 deaths were related to mycosis fungoides and these were significantly associated with higher T. The 54 T1N0 patients who had 35 Gy had a 10-year mycosis fungoides-specific survival of 100%. CONCLUSION: Total skin electron beam radiation gives good results with T1N0B0M0 disease. T3-4 disease is less likely to respond, it relapses more quickly, and it implies a poorer survival, but radiation offers palliation. T2 responds like T1, but relapses like T3-4. T2 also implies an intermediate survival. These results have implications for staging, informed consent, optimizing radiation treatment, and clinical trials.

Female↗
PubMed1994

Patterns of failure following loco-regional radiotherapy in the treatment of limited stage small cell lung cancer.

PURPOSE: The probability of treatment resistant cells developing in a tumor, such as small cell lung cancer (SCLC) which has a rapid cell cycle time, is a function of the number of tumor cells present and of time. Theoretically, the development of resistance to chemotherapy and radiotherapy should be minimized by using all treatment modalities early in the treatment program. METHODS AND MATERIALS: The importance of the timing of loco-regional radiotherapy was assessed in a multi-institution randomized study. Three hundred and eight patients with limited small cell lung cancer (LSCLC) were given three cycles of cyclophosphamide, doxorubicin and vincristine alternating with three cycles of etoposide and cisplatin. In addition, patients were randomized to receive locoregional radiotherapy: 40 Gy in 15 fractions in 3 weeks with treatment planning techniques to limit the spinal cord dose to be < or = 35 Gy either with the first cycle (early) or with the sixth cycle of chemotherapy (late). Responding patients received prophylactic brain irradiation (25 Gy in 10 fractions in 2 weeks) after completion of locoregional radiotherapy and chemotherapy. RESULTS: 96% of the 155 eligible patients allocated to the "early" arm and 87% of the 153 allocated to the "late" arm received locoregional radiotherapy; 26 patients did not receive locoregional radiotherapy. The mean field sizes were similar in both arms. The mean radiation doses were significantly less in the "early" arm (p = 0.0319 Wilcoxon rank sum test). Any differences in the frequency of toxicities were minor. All patients have been followed for at least 2 years and the median follow up is 4 years. 64% had a complete response in the "early" arm compared with 56% in the "late" arm (p = 0.137). Survival was measured from the start of chemotherapy. There was a significant improvement in survival in the "early" arm; median survival was 21.2 months compared with 16.0 months in the "late" arm (p = .008 log rank test). Survival at 2, 3, and 4 years was 40%, 32%, and 25%, respectively, for the "early" arm and 33%, 22%, and 15% for the "late" arm. There were 232 (75%) recurrences among those patients whose disease recurred. The proportion who had local recurrence within the radiation field was 41% and 39% for "early" and "late" treatment arms respectively. The proportion of brain metastases in the "late" arm (28%) was significantly higher than in the "early" arm (18%) p = .0425 Fishers' exact test. CONCLUSION: We conclude that early administration of locoregional radiotherapy in a combined modality treatment is superior to late consolidative locoregional radiotherapy in limited small cell lung cancer.

Brain Neoplasms↗
PubMed1994

Variations in the management and outcome of non-small cell lung cancer in Ontario.

Prospectively gathered information in the Ontario Cancer Foundation's computerized clinical database was analysed to provide a description of the management of 12,399 patients with unresected non-small cell lung cancer (NSCLC) registered at seven regional cancer centres in Ontario between 1982 and 1991. Overall, 44% received initial thoracic radiotherapy, 19% received initial radiotherapy to metastatic sites, and 36% received no immediate radiotherapy. Of those who received thoracic radiation 41% received doses > or = 40 Gy and 59% received doses < 40 Gy. Among the seven centres, the proportion of patients receiving initial thoracic radiotherapy ranged from 41% to 56% (p < 0.001), and the proportion of those receiving doses > or = 40 Gy ranged from 30% to 68% (p < 0.001). Between 1982 and 1991, the overall proportion of patients who received initial thoracic radiotherapy decreased from 48% to 38%, the proportion of those receiving high dose treatment decreased from 55% to 28%, and the mean number of fractions given to the chest decreased from 17 to 10. Only 10% received chemotherapy at any time, and that proportion ranged from 3% to 21% (p < 0.001) among the seven centres. Between 1982 and 1991 the proportion of patients receiving chemotherapy decreased significantly from 15% to 8% (p < 0.001) across the Cancer Foundation as a whole. These wide variations in management policies were not associated with any significant differences in survival, which was similar at all seven centres, and remained constant between 1982 and 1991.

Adenocarcinoma↗
PubMed1994

Placebo-controlled randomized trial of infusional fluorouracil during standard radiotherapy in locally advanced head and neck cancer.

PURPOSE: To determine whether the addition of infusional fluorouracil (I-FU) to standard radiotherapy improves survival at acceptable toxicity in patients with locally advanced squamous cell head and neck cancer (SCHNC). PATIENTS AND METHODS: Consenting patients with an Eastern Cooperative Oncology Group (ECOG) performance status < or = 2; with stage III or IV SCHNC of the oral cavity, oropharynx, hypopharynx, or larynx; and who were recommended for radiotherapy with curative intent received 66 Gy of radiation therapy delivered in 2-Gy fractions once daily 5 days per week for 6 1/2 weeks. Those in the experimental arm received I-FU 1.2 g/m2/d, as a 72-hour infusion in the first and third weeks of radiation. Saline infusions were used in the placebo arm. RESULTS: One hundred seventy-five patients were randomized (88 to I-FU and 87 to placebo), and the treatment arms were well balanced. The complete response rate was 68% for I-FU and 56% for placebo (P = .04). The overall median survival duration was 33 months for I-FU and 25 months for placebo (P = .08). Progression-free survival also favored I-FU (P = .06). Toxicity was greater in I-FU patients, but did not interfere with the scheduled delivery or completion of radiation. CONCLUSION: The addition of I-FU to standard radiation in SCHNC improved the complete response rate and was associated with beneficial trends in progression-free and overall survival compared with radiation alone. I-FU patients also experienced greater morbidity, but this did not compromise delivery of radiotherapy.

Aged↗
PubMed1993

The Head and Neck Radiotherapy Questionnaire: a morbidity/quality-of-life instrument for clinical trials of radiation therapy in locally advanced head and neck cancer.

PURPOSE: The purpose of this study was to develop and validate an instrument for clinical trials to measure radiation-related acute morbidity and quality of life from the perspective of patients with head and neck cancer (HNC) treated with radiotherapy. METHODS: The Head and Neck Radiotherapy Questionnaire (HNRQ) was developed by a panel of health care workers and patients, was pretested in a pilot study of HNC patients, and was validated in a randomized double-blind trial of concomitant fluorouracil (FUra) infusional therapy (1.2 g/m2 per 24 hours) or saline placebo administered for 72 hours in the first and third weeks of a 6 1/2-week course of radiation therapy. The HNRQ was validated against existing toxicity and performance status indices, all of which were measured weekly for the 6 1/2 weeks of treatment and for 4 weeks posttreatment. RESULTS: There were three a priori constructs: (1) that the HNRQ scores would conform to a shallow U-shaped pattern to reflect declining quality of life (increasing morbidity) during radiation and recovery posttreatment; (2) that the HNRQ would correlate with existing toxicity indices (World Health Organization [WHO] stomatitis, Byfield stomatitis, WHO skin toxicity, Eastern Cooperative Oncology Group [ECOG] and Karnofsky performance status); and (3) that the HNRQ would discriminate between FUra and placebo groups. The HNRQ and its domain scores all showed a change from baseline reflecting increased morbidity during radiation (analysis of variance [ANOVA], P < .00001). The HNRQ correlated well with all other indices (r > or = .60), and domain scores correlated best with other indices that assess the same symptom complex (eg, HNRQ skin domain and WHO skin toxicity index, r = .77). There was a significant difference in HNRQ scores between the FUra and placebo groups during radiation (ANOVA, P = .0007), and all HNRQ domains also discriminated between the treatment groups. CONCLUSION: The HNRQ is a valid measure of acute morbidity due to radiation therapy in patients with locally advanced HNC, and may be useful as an outcome measure for future clinical trials of radiation treatment strategies.

Carcinoma, Squamous Cell↗
PubMed1991

Management of oral mucosal dysplasia with beta-carotene retinoic acid: a pilot cross-over study.

Mucosal dysplasia in the head and neck region is recognized to be a precancerous lesion. Between January 1983 and December 1987, a pilot study was conducted at the Manitoba Cancer Treatment and Research Foundation to determine the effects of beta-carotene and cis-retinoic acid on mucosal dysplasias. Eighteen patients were treated with a "cross-over" regimen. The overall response to treatment was 61%, with 33.3% complete responses. Patients who smoked had a significantly better response than nonsmokers. The response rate for 9 of 11 smokers was 81.2%, and 2 of 7 nonsmokers or 28.6% responded to this protocol. The beneficial effect of these drugs should be established by prospective, randomized trial in high risk populations.

Adult↗
PubMed1990

Physical aspects of external beam radiotherapy for the treatment of malignant pleural mesothelioma.

The optimization of radiotherapy for the treatment of malignant mesothelioma highlights many of the currently outstanding problems in clinical radiation physics. The experimental investigation of an intuitively attractive irradiation technique with combined photon and electron beams using a specially constructed phantom has established that, due to the penetration in low density material of both primary electrons and those secondary to photon irradiation, the normal lung tissue is not spared to any significant degree by such a technique. Furthermore, great care needs to be exercised in the treatment planning calculations for this approach if absolute dosimetry errors as large as 50% are to be avoided.

Electrons↗
PubMed1990

Quantitative computed tomography of the brain with xenon enhancement: a phantom study with the GE9800 scanner.

A recently proposed application of quantitative computed tomography is in the study of cerebral blood flow and partition coefficient using stable xenon as a freely diffusible, radio-opaque tracer. Central to the method is the calibration factor describing the relationship between CT number and xenon concentration in the brain. In this paper we examine the influence of temporal fluctuations, kVp, radial position and beam hardening on this calibration factor through the analysis of a series of phantom measurements. We conclude that under clinically realistic conditions and with correlations for temporal fluctuations, the error associated with the calibration factor is less than 2%. Furthermore, errors of this magnitude translate into errors of less than 3% in derived blood flow and partition coefficient values obtained using xenon-enhanced computed tomography.

Brain↗
PubMed1988

Chemotherapy can prolong survival in patients with advanced non-small-cell lung cancer--report of a Canadian multicenter randomized trial.

The survival benefit of combination chemotherapy to patients with advanced non-small-cell carcinoma of the lung (NSCLC) is controversial. To study this question, the National Cancer Institute of Canada (NCIC) Clinical Trials Group conducted a prospective randomized trial comparing best supportive care (BSC) to two chemotherapy regimens, vindesine and cisplatin (VP), and cyclophosphamide, doxorubicin, and cisplatin (CAP). Between February 1983 and January 1986, 23 centers across Canada entered 251 patients on study. Eighteen centers participated in the three-arm schema (150 patients); centers choosing not to participate in a study with a no-chemotherapy arm followed a two-arm schema comparing VP with CAP (101 additional patients). Altogether, 233 patients were eligible. Patients had measurable or evaluable disease, with either distant metastases (82.5%) or bulky limited disease considered inoperable or unsuitable for radical radiotherapy. The treatment groups were comparable in terms of age, sex, performance status, histology, disease extent, and weight loss. The overall response rates (complete response [CR] plus partial response [PR]) on the chemotherapy arms were CAP, 15.3%, and VP, 25.3% (P = .06). Patients on the three-arm portion of the trial had a median survival of 32.6 weeks when treated with VP, 24.7 weeks with CAP, and 17 weeks with BSC. The significance of the differences in survival, adjusted for prognostic factors, is as follows: chemotherapy v BSC, P = .02; VP v BSC, P = .01; and CAP v BSC, P = .05. Toxicity on the chemotherapy arms was significant, with leukopenia of severe or greater degree occurring in 37.8% (CAP) and 40.0% (VP), severe vomiting in 12.2% (CAP) and 23.3% (VP), and severe neurotoxicity in 15.6% (VP).

Antineoplastic Combined Chemotherapy Protocols↗