Biomedical subjects

L Stitt

Publications and source records attributed to L Stitt.

At least 19 recordsLinked to original sources

PubMed2006

Assessing the prognostic significance of transrectal ultrasound extracapsular extension in prostate cancer.

AIMS: To determine the prognostic value of transrectal ultrasound (TRUS)-detected extraprostatic disease for prostate cancer in patients receiving radical external-beam radiation therapy (EBRT). MATERIALS AND METHODS: A chart review of 181 patients treated with radical EBRT for prostate cancer was conducted. All patients underwent TRUS assessment by one radiologist. The median radiation dose delivered to the prostate was 66 Gy (range 53-70 Gy) in 33 fractions (range 20-39 fractions). Median follow-up time for all patients was 6.5 years. Sixty-four (35%) out of 181 patients were found to have extracapsular disease on TRUS. Clinical relapse was defined as the first occurrence of either salvage hormonal therapy administration by the treating oncologist or clinical, radiological, and/or pathologic evidence of recurrent or progressive disease. In terms of biochemical failure, two prognostic variable analyses were carried out using both the American Society for Therapeutic Radiology and Oncology (ASTRO) consensus guidelines and the Houston definition of biochemical failure. The primary end point for the prognostic variable analyses was time to first clinical or biochemical failure (CBF). RESULTS: For time to CBF using the ASTRO consensus guidelines for biochemical failure, univariable analysis revealed that the prostate-specific antigen (PSA) (P = 0.018), clinical T stage (P = 0.002), Gleason score (P = 0.021), adjuvant hormonal therapy (P = 0.032) and TRUS T staging (P = 0.0001) were statistically significant prognostic factors. On multivariable analysis, clinical T stage (P = 0.051) was of borderline statistical significance, whereas PSA (P = 0.036), TRUS T stage (P = 0.0002) and adjuvant hormonal therapy (P = 0.015) were found to be independent prognostic factors. For time to CBF using the Houston definition of biochemical failure, univariable analysis revealed that PSA (P = 0.001), Gleason score (P = 0.026) and prostate volume (P = 0.013) were statistically significant prognostic factors. On multivariable analysis, PSA (P = 0.002), Gleason score (P = 0.012), and adjuvant hormonal therapy (P = 0.041) were found to be independent prognostic factors. TRUS T staging was not found to be independently significant. CONCLUSIONS: A clear role for TRUS staging as an independent prognostic factor, in the setting of other more established variables, such as Gleason grade, PSA, and digital rectal examination (DRE) T stage, was not confirmed in this study, population.

Aged↗

PubMed2006

Early outcomes of coronary artery bypass with and without cardiopulmonary bypass in octogenarians.

BACKGROUND: Off-pump coronary artery bypass (OPCAB) surgery has been successfully used in diverse patient populations and has been postulated to be safer than conventional coronary artery bypass (CCAB) surgery in some high-risk patients, including the elderly. OBJECTIVE: To compare the safety of OPCAB surgery versus CCAB surgery in the octogenarian population of two large southwestern Ontario cardiac surgical units. RESULTS: Two hundred thirty-six consecutive octogenarians underwent primary isolated coronary artery bypass surgery from November 2000 to March 2005. Patients undergoing OPCAB surgery tended to have higher Parsonnet scores, while patients undergoing CCAB surgery had a greater number of emergent operations. The Canadian Cardiovascular Network predicted that mortality risk was similar in both groups. In-hospital mortality was similar between groups, as was postoperative myocardial infarction and new onset of renal dysfunction. However, in the OPCAB group, there was a decreased incidence of postoperative neurological dysfunction (2.3% in the OPCAB group versus 10.5% in the CCAB group, P=0.01), in particular cerebrovascular accidents (1.5% in the OPCAB group versus 7.6% in the CCAB group, P=0.05), and a decreased incidence of prolonged intubation (5.3% in the OPCAB group versus 13.3% in the CCAB group, P=0.04). Multivariable analysis found that cardiopulmonary bypass had no significant impact on mortality or length of stay. CONCLUSIONS: In octogenarian patients, OPCAB surgery is as safe as CCAB surgery in terms of mortality and major morbidity. Furthermore, a significant reduction in neurological dysfunction and prolonged intubation was seen in the OPCAB group compared with the CCAB group.

Aged, 80 and over↗

PubMed2005

Timing of ball release in overarm throws affects ball speed in unskilled but not skilled individuals.

We tested the hypothesis that variability in the timing of ball release in overarm throws affects ball speed. Nine unskilled and six skilled throwers made 30 throws fast and accurately from a sitting and standing position. Angular positions of finger and arm segments were recorded with search-coils at 1000 Hz; ball speed was measured with a radar gun. The time of ball release from the fingertips was measured with respect to seven arm kinematic reference points. Mean timing windows for ball release were 28 ms for unskilled throwers and 7 ms for skilled throwers. Mixed-model analyses of variance showed that a there was a statistically significant relationship between ball speed and the timing of ball release in unskilled throwers, but not in skilled throwers. This was presumably due to the difference in variability of the timing of ball release between the two groups. In contrast, skilled throwers showed a relationship between ball speed and peak forearm angular velocity (one measure of arm speed). We conclude that although variability in the timing of ball release can affect ball speed, this is only a major factor in unskilled throwers. When skilled throwers throw fast, variability in ball speed is due to variability in arm speed.

Adult↗

PubMed2004

The stability of utility scores: test-retest reliability and the interpretation of utility scores in elective total hip arthroplasty.

PURPOSES: Are utility scores for hypothetical health states stable over time even when the health of the patient changes dramatically? Can investigators who use scores for hypothetical states be confident about the stability of those scores? The first purpose is to assess the stability of standard gamble utility scores for three hypothetical health states describing mild, moderate, and severe osteoarthritis (OA) (test-retest reliability). How should investigators interpret utility scores? The second purpose is to provide evidence on the marker-state approach to assist in interpreting utility scores. BACKGROUND: SG scores for three hypothetical marker states and the patient's current state were obtained at multiple times in a longitudinal study of elective total hip arthroplasty (THA). SG scores for current health increased from a mean of 0.59 pre-surgery to 0.76 post-surgery. METHODS: Test-retest reliability was assessed using the intra-class correlation coefficient (ICC). The effects of time on scores were analysed using an analysis of covariance. RESULTS: At the group level the marker-state scores were stable. Mean scores for mild, moderate, and severe OA were 0.69, 0.61, and 0.41. With respect to test-retest reliability, ICCs varied from 0.49 to 0.62. In general, time did not affect the scores for the three marker states. CONCLUSIONS: Group-level standard gamble scores are stable. At the individual level scores for hypothetical health states are somewhat stable over time. The marker states assist in interpretation indicating that, on average, THA converted moderate OA to better than mild.

Analysis of Variance↗

PubMed2004

Evaluation of an osteoporosis self-referral program to enhance management outcomes.

Osteoporosis is a common but undertreated condition. While bone density is known to predict fracture risk, there is currently no economical way of measuring general population risk. This study examined whether an economical screening technique could improve diagnosis and lead to appropriate outcomes in the management of osteoporosis. A self-referral program was established to provide women with information about osteoporosis and an individualized risk assignment. A high-risk designation was provided for postmenopausal women below the lower tertile of a calcaneal broadband ultrasound attenuation (BUA) (< or = 58 db/MHz) or those with a SCORE value > or = 6. A telephone survey was conducted 6 mo after program registration to evaluate osteoporosis management outcomes. Of 271 women surveyed, 181 (67%) were postmenopausal and thus potential candidates for estrogen replacement, and 21% and 63% were assigned a high-risk profile by either calcaneal ultrasound or SCORE, respectively. Women at higher risk were significantly more likely to discuss osteoporosis with their family physician (p < 0.001), and to undergo further testing with dual X-ray absorptiometry measurement (p < 0.005). Utilization of estrogen replacement by postmenopausal women at time of survey was significantly increased compared to registration (p = 0.01). The self-referral program positively impacted decisions women made about preventing osteoporosis, particularly if they considered themselves at higher risk.

Absorptiometry, Photon↗

PubMed2001

Results of a policy of surveillance alone after surgical management of pediatric low grade gliomas.

PURPOSE: To document the incidence of tumor progression in pediatric patients with low-grade gliomas (LGGs), with particular emphasis on those patients who did not receive postoperative chemotherapy or radiotherapy (RT). METHODS AND MATERIALS: A database of 128 patients with histologically confirmed LGGs (World Health Organization Grade I-II), age <or=18 years, who had been referred to the London Regional Cancer Center and Dalhousie University between 1979 and 1995, was compiled. RESULTS: The median follow-up for the 128 patients was 7.3 years. Of the 128 patients, 63 were male and 65 female. The median age was 7.0 years (range 0-18). Twenty-five patients underwent gross complete resection, 63 subtotal resection, and 40 patients biopsy. Ninety-one percent (n = 117) of the tumors were astrocytomas, of which 22 were pilocytic, 3 were oligodendrogliomas, 7 were mixed gliomas, and 1 was a ganglioglioma. Of the 103 subtotally resected patients, 48 received postoperative RT (median dose 59 Gy in 25 fractions) and 10 patients were irradiated at the time of tumor progression. The 5-year overall survival was 86%, cause-specific survival 88%, and 5-year progression-free survival 79%. The results of the univariate analysis of the overall survival by the Wilcoxon model were statistically significant for Karnofsky performance status (p = 0.03), RT timing (i.e., postoperative vs. deferred; p = 0.05), and tumor location (p = 0.02). The analysis of progression-free survival confirmed the statistical significance of the extent of surgical resection (i.e., complete vs. subtotal resection; p = 0.02). None of the patients who underwent gross complete resections received postoperative RT and none developed tumor recurrence. Of the 103 patients who had subtotal resections, 33 had progression, with a median postprogression survival of 39 months. The rate of tumor progression among the subtotally resected LGG patients who did not receive immediate postoperative RT was 42%. The timing of RT and tumor location lost statistical significance for overall survival when the completely resected patients were excluded from the analysis. CONCLUSIONS: The extent of surgical resection was prognostically significant for progression-free survival but lost significance as a prognostic factor once the complete resection patients were excluded from the analysis. At a median survival of 7.3 years, 42% of the subtotally resected LGG patients who did not receive immediate postoperative RT had tumor progression. No statistically significant difference in survival was seen between the postoperative and deferred RT groups, even though the postoperative RT group was a group with poorer prognostic features (bulky residual tumor postoperatively, Karnofsky performance status <70, and nonhemispheric, noncerebellar tumors), indicating that RT may be beneficial for this particular subset of patients.

Analysis of Variance↗

PubMed2001

PCV for oligodendroglial tumors: in search of prognostic factors for response and survival.

BACKGROUND: We report survival and pretreatment prognostic factors for survival and chemosensitivity in 53 oligodendrogliomas treated with PCV (procarbazine, lomustine and vincristine) chemotherapy. METHODS: A total of 53 patients with histologically proven oligodendroglioma, anaplastic oligodendroglioma or oligo-astrocytoma and treated with PCV were extracted from the London Regional Cancer Center database. A retrospective review was conducted to evaluate overall survival and pretreatment prognostic factors for survival and chemosensitivity. RESULTS: The median survival time from diagnosis was 123.6 months. The overall five- and ten-year survival rates were 72.7% and 52.7% respectively. Age <40, seizure as an initial symptom, absence of cognitive deficit and presence of a homogeneous hypodense lesion without contrast enhancement on the initial pretreatment CT scan were all factors independently associated with favorable outcome. The presence of increased cellularity, pleomorphism, mitosis, vascular proliferation and grading as an anaplastic lesion using these surrogates on pathological assessment, were all associated with an unfavorable outcome in univariable analysis. In multivariable analysis, only the anaplastic grading and presence of increased cellularity were significant determinants of unfavorable survival. The only factor adversely associated with chemosensitivity was the presence of a focal symptom at presentation. CONCLUSION: Overall survival is significantly longer in oligodendroglial lesions than in fibrillary astrocytic tumors. A two tier grading system using standard morphological features seems accurate in predicting outcome in these patients. The presence of a neoplastic astrocytic component does not seem to impact the outcome. No clinical, radiological or pathological factor could be identified to reliably predict chemotherapy response.

Adult↗

PubMed2001

Thymidylate synthase expression in stage II and III colon cancer: a retrospective review.

This study is a retrospective analysis of thymidylate synthase (TS) levels in patients with stage II (T3 or T4) and III colon cancer. Two groups of patients were identified: one undergoing surgery alone (98 patients) and the second receiving adjuvant 5-fluorouracil chemotherapy (112 patients). TS analyses were carried out using the 106 monoclonal antibody and a published grading system dividing staining into high and low intensity. The distribution of patients with low versus high TS levels was similar in the two groups. There was no association between TS staining intensity and grade, stage or location of primary. Seventy-nine patients have relapsed: 46 (48%) in the surgery only group, 33 (30%) in the adjuvant therapy group (median follow-up: 51 and 61 months). Similar proportions relapsed when analyzed according to TS: in the surgery only group, 41% of patients with low TS, 48% with high TS; in the adjuvant group, 31% with low TS, 30% with high TS. In the surgery only group, a trend toward improved disease-free survival (DFS) was seen in the low TS group (84 versus 63% at 2 years, p = 0.08). No difference was seen in overall survival. There were no differences in DFS or overall survival in patients receiving adjuvant therapy according to TS intensity. The trend for worse outcome in patients with high TS is consistent with previous reports. The lack of difference in outcome for patients with low and high TS receiving chemotherapy suggests that high TS levels may predict greater benefit from adjuvant treatment.

Aged↗

PubMed2000

Allelic loss of chromosome 1p and radiotherapy plus chemotherapy in patients with oligodendrogliomas.

INTRODUCTION: Allelic loss of the short arm of chromosome 1 predicts radiographic response to chemotherapy and long overall survival times in patients with anaplastic oligodendrogliomas. Using a database of patients with oligodendrogliomas in whom chromosome 1p status was known, we explored whether allelic loss of 1p also predicted longer duration of tumor control when radiotherapy was part of the initial treatment of these patients. MATERIALS AND METHODS: We measured progression-free survival following radiotherapy in a cohort of patients with World Health Organization (WHO) Grade II and WHO Grade III oligodendrogliomas. The effects on progression-free survival of patient age, Karnofsky performance score (KPS), tumor grade when irradiated and chromosome 1p status were examined by univariate and multivariate statistical analyses. For the subset of patients with newly diagnosed anaplastic oligodendrogliomas, relationships between use of chemotherapy, chromosome 1p status and progression-free survival were also examined. RESULTS: Fifty-five patients (29 male, 26 female; ages 18-75 years; median, 44 years; KPS 50-90, median 80) were irradiated for either a WHO Grade II (n = 19) or Grade III (n = 36) oligodendroglioma. Twenty-eight patients had chemotherapy immediately prior to radiotherapy, and 27 had chemotherapy at progression following radiotherapy. The median radiation dose was 54 Gy in 30 fractions. Loss of heterozygosity (LOH) at chromosome 1p was evident in 36 tumors and absent in 19. Overall median progression-free survival after radiotherapy was 40.4 months. Median progression-free survival was 55.0 months for patients whose tumors harbored 1p loss vs. 6.2 months for those patients whose tumors retained both copies of chromosome 1p (p < 0.001). On both univariate and multivariate analyses, chromosome lp loss was the principal independent predictor of longer progression-free survival for patients with Grade II and III oligodendrogliomas. For Grade III oligodendrogliomas, chemotherapy as an adjunct to radiotherapy prolonged tumor control for those patients whose tumors harbored allelic loss of chromosome 1p (p = 0.004). CONCLUSION: These data suggest allelic loss of chromosome 1p in patients with oligodendroglial neoplasms predicts longer progression-free survival among patients receiving radiotherapy +/- chemotherapy as part of their initial treatment. Chromosome 1p loss may be an important stratification variable in future therapeutic trials of oligodendroglioma.

Adolescent↗

PubMed2000

Radiation treatment for cervical esophagus: patterns of practice study in Canada, 1996.

PURPOSE: To assess the patterns of practice among Canadian radiation oncologists who treat esophageal cancers, using a trans-Canada survey, completed at the end of 1996. METHODS AND MATERIALS: One of 3 case presentations of different stages of cervical esophageal cancer was randomly assigned and sent to participating radiation oncologists by mail. Respondents were asked to fill in questionnaires regarding treatment techniques and to outline target volumes for the boost phase of radiotherapy. Radiation oncologists from 26 of 27 (96%) of all Canadian centers participated. RESULTS: High-energy X-rays (>/= 10 MV) were employed by 68% of the respondents in part of the treatment course. The majority (83%) of the radiation oncologists used at least two phases of treatment. Very few, 10 of 59 (17%), responses started with multifield treatment. The most frequently used prescription dose was 60 Gy/30 fractions/6 weeks, given with concurrent chemotherapy. Dose prescriptions were to the isocenter in 39 of 48 (81%) or to a particular isodose line in 9 of 48 (19%) of respondents. CONCLUSION: There was a variety of radiation treatment techniques in this trans-Canada survey. The majority of the patients had combined cisplatin-based chemoradiation. The isocenter was not used consistently as a dose prescription point.

Aged↗

PubMed2000

Outcome after ovarian/adnexal metastectomy in metastatic colorectal carcinoma.

BACKGROUND: Ovarian metastases are reported to occur in 3-8% of women undergoing surgical resection of a primary colorectal adenocarcinoma. Information on clinical outcome after metastectomy for these patients is limited. Patients and Methods A computerized search of the medical record archive at the London Regional Cancer Centre (LRCC) identified 38 patients with metastatic colorectal cancer who underwent ovarian metastectomy between 1984-98. RESULTS: Median age at diagnosis colorectal cancer was 54.5 years (range: 19-76). Nine women were <50 and 29 women were >50 years old at diagnosis of metastases. Ovarian metastases were diagnosed a median of 15 months (range: -2-65) after diagnosis of the primary malignancy. Complete resection was achieved in 19 patients. Nodal status of the primary tumor, presence of synchronous metastases, adjuvant therapy for colorectal cancer as well as interval to diagnosis of ovarian metastases had no significant effect on survival. Median survival for women aged <50 was 34.5 months vs. 17 months for those >50 (P = 0.22). Women with metastases confined to the pelvis survived a median of 31 months (range: 20-42) compared to 14 months for women with disease outside of the pelvis (P = 0.011). Median survival after complete metastectomy was 31 months (range: 24-45) and after palliative debulking was 14 months (range: 7-20) (P = 0.014). CONCLUSIONS: Our results suggest that ovarian metastectomy may significantly improve overall survival in younger women able to undergo complete metastectomy for disease confined to the pelvis. Results also suggest that extent of disease and feasibility of complete resection may significantly impact on prognosis and must be carefully evaluated before surgery.

Adenocarcinoma↗

PubMed2000

Management issues in chordoma: a case series.

This study presents a combined case series of chordomas from two Canadian institutes. Twenty-seven patients were identified for the period 1954-1998. Management issues with regard to diagnostic pitfalls, selection of charged particle treatment and retreatment of recurrences are discussed. The diagnosis of early stage chordoma requires a high index of suspicion. One patient in the series presented with hoarseness and is described in detail. The diagnosis was made coincidentally by a computed tomographic scan of the head, performed after a motor vehicle accident. The planning of both surgery and radiotherapy was optimized by using magnetic resonance imaging. A review of the literature supports the use of a combined surgical and radiotherapeutic approach.

Adult↗

PubMed2000

Pelvic fractures following irradiation of endometrial and vaginal cancers-a case series and review of literature.

PURPOSE: To review the induction of pelvic fractures as a result of radiation therapy and to assess their management. MATERIALS AND METHODS: The charts of patients with endometrial and vaginal cancers irradiated between 1991 and 1995 were reviewed. All patients were treated with megavoltage machines, energy ranging from cobalt to 25 MV photons. RESULTS: We treated 336 patients, with a median follow-up duration of 28.9 months (range 0-73.3). Sixteen patients had symptomatic pelvic fractures. The 5-year actuarial incidence of symptomatic pelvic fracture was 2.1%. All patients had pain as the first symptom. The median time of onset was 11 months (range 4-46). Imaging studies of 37.5% (6/16) were initially interpreted to be recurrent malignancy. All patients were managed conservatively and nine patients showed radiological evidence of healing over a median time of 13 months (range 2-34). Six patients had specific drug treatment including provera, premarin, calcium supplements, or pamidronate. Of these, five healed. For the ten patients who did not have any specific treatment, only four showed signs of healing at the time of last follow-up. There was a trend toward earlier healing with specific drug treatment (P=0.11). CONCLUSIONS: Fractures can easily be mistaken for metastatic lesions (37.5% in this series) which might be treated with further irradiation. Although not statistically significant, there was a trend towards early healing with drug therapy. More studies are required to generate quantitative data for dose-response relationships and to evaluate the effect of drug therapy on the healing of such fractures.

Aged↗

PubMed2000

Standard dose (Mayo regimen) 5-fluorouracil and low dose folinic acid: prohibitive toxicity?

Despite the perception that standard 5-fluorouracil/folinic acid (5-FU/FA) (425 mg/m2 per day and 20 mg/m2 per day intravenously once daily x 5 every 4 or 5 weeks) is well tolerated, we have been impressed by toxicity seen and frequent need for dose modification. We performed a retrospective analysis to quantitate the proportion of patients experiencing toxicity and attempted to identify associated clinical characteristics. One hundred thirty-four patients received 5-FU/FA at standard doses described by the Mayo regimen. Patient characteristics were as follows: female 35%, median age 66 years, Eastern Cooperative Oncology Group performance status less than or equal to 2, 96%. Sixty-eight percent received chemotherapy for metastatic disease. Forty-seven patients (35%+/-8%) experienced significant toxicity and were unable to receive the second cycle as scheduled: 76% required dose reduction, 11% discontinued therapy (including two toxic deaths), 11% discontinued therapy during the first cycle, and 2% required dose delay. Logistic regression was used to explore the following as predictors of toxicity: age, sex, performance status, adjuvant versus metastatic setting, prior chemotherapy, prior radiation, mean corpuscular volume, red blood cell distribution width, albumin, alkaline phosphatase, aspartate aminotransferase, bilirubin, and calculated creatinine clearance. No clinical characteristic was found to predict toxicity. Only high bilirubin approached statistical significance. We conclude that standard 5-FU/FA, when used in the general population, is associated with significant toxicity. Known clinical characteristics are not helpful in predicting toxicity. The lack of previous formal phase I evaluation of this regimen of 5-FU/FA raises concerns regarding its safety and generalizability in clinical practice.

Adult↗

PubMed2000

Chemotherapy in neuroendocrine/Merkel cell carcinoma of the skin: case series and review of 204 cases.

PURPOSE: To study the use of chemotherapy for Merkel cell carcinoma (MCC) of the skin. PATIENTS AND METHODS: Twenty-five cases of MCC were treated at the London Regional Cancer Center between 1987 and 1997. Thirteen cases treated with chemotherapy were reviewed with 191 cases from the literature. RESULTS: At presentation, 24 patients had localized skin lesions (stage I) and one had locoregional involvement (stage II). Among the nine cases with recurrent nodal disease, six had chemotherapy as a component of salvage treatment. They were all free of disease at a median of 19 months (range, 12 to 37 months). In contrast, two patients who had salvage radiotherapy alone died of disease. Overall survival (OS) and disease-free survival (DFS) were 59% and 43%, respectively, at two years. Median OS and DFS were 29 months (range, 1 to 133 months) and 9 months (range, 1 to 133 months), respectively. Nodal disease developed in 12 (50%) of 24 patients with stage I disease, and distant metastases developed in six (25%) of 24. Including those from the literature, there were 204 cases treated with chemotherapy. Cyclophosphamide/doxorubicin (or epirubicin)/vincristine combination +/- prednisone was the most commonly used chemotherapy regimen (47 cases), with an overall response rate of 75.7% (35.1% complete, 35. 1% partial, and 5.4% minor responses). Etoposide/cisplatin (or carboplatin) was the next most commonly used regimen (27 cases), with an overall response rate of 60% (36% complete and 24% partial responses). The difference in response rate was not statistically significant (P =.19). Among the 204 cases, there were seven (3.4%) toxic deaths. CONCLUSION: Chemoradiation for locally recurrent or advanced disease may be an option for patients with a good performance status.

Aged↗

PubMed1999

Pretreatment factors predict overall survival for patients with low-grade glioma: a recursive partitioning analysis.

PURPOSE: Three databases were pooled and analyzed to determine which groupings of prognostic factors best predicted overall survival for patients with low-grade gliomas treated with surgery and immediate or delayed radiotherapy. METHODS AND MATERIALS: Databases of patients with low-grade gliomas compiled at the London Regional Cancer Centre (LRCC), the Norwegian Radium Hospital (NRH), and the University of California, San Francisco (UCSF) were merged. Inclusion criteria for the pooled analysis included: age > or =18 years and histologically confirmed low-grade (World Health Organization Grade II) supratentorial fibrillary astrocytoma, oligodendroglioma or mixed oligoastrocytoma. Factors analyzed for prognostic significance included: age at diagnosis, gender, seizures at presentation, presence of enhancement on computed tomography (CT) or magnetic resonance imaging (MRI), Karnofsky Performance Status (KPS) at diagnosis, histology, extent of surgical resection, timing of radiotherapy, and treating institution. Univariate and multivariate analysis of overall survival for these factors was performed. Recursive partitioning was performed to generate prognostic groups using these factors. RESULTS: From the combined databases, 401 patients were eligible for analysis. Median survival for the entire group was 95 months/7.9 years. On univariate analysis age 18-40, presence of seizures at presentation, KPS > or =70, treating institution, and absence of contrast enhancement were associated with improved overall survival. On multivariate analysis, these factors remained independent predictors of improved overall survival. Recursive partitioning analysis yielded four prognostic groups with statistically different median survivals (MS): Group I (n = 41: KPS <70, age >40) MS 12 months; Group II (n = 34: KPS > or =70, age >40, enhancement present) MS 46 months; Group III (n = 138: KPS <70, age 18-40 or KPS > or =70 age >40, no enhancement) MS 87 months; Group IV (n = 188: KPS > or =70, age 18-40) MS 128 months. CONCLUSION: Clusters of pretreatment prognostic factors described subgroups of low-grade glioma patients with divergent overall survivals. Consideration of these prognostic subgroups may be important when considering timing of interventions for these patients and in the stratification of patients for clinical trials.

Adult↗

PubMed1998

Variability of target volume delineation in cervical esophageal cancer.

PURPOSE: Three-dimensional (3D) conformal radiation therapy (CRT) assumes and requires the precise delineation of the target volume. To assess the consistency of target volume delineation by radiation oncologists, who treat esophageal cancers, we have performed a transCanada survey. MATERIALS AND METHODS: One of three case presentations, including CT scan images, of different stages of cervical esophageal cancer was randomly chosen and sent by mail. Respondents were asked to fill in questionnaires regarding treatment techniques and to outline boost target volumes for the primary tumor on CT scans, using ICRU-50 definitions. RESULTS: Of 58 radiation oncologists who agreed to participate, 48 (83%) responded. The external beam techniques used were mostly anterior-posterior fields, followed by a multifield boost technique. Brachytherapy was employed by 21% of the oncologists, and concurrent chemotherapy by 88%. For a given case, and the three volumes defined by ICRU-50 (i.e., gross tumor volume [GTV], clinical target volume [CTV], and planning target volume [PTV]) we determined: 1. The total length in the cranio-caudal dimension; 2. the mean diameter in the transverse slice that was located in a CT slice that was common to all participants; 3. the total volume for each ICRU volume; and 4. the (5, 95) percentiles for each parameter. The PTV showed a mean length of 14.4 (9.6, 18.0) cm for Case A, 9.4 (5.0, 15.0) cm for Case B, 11.8 (6.0, 16.0) cm for Case C, a mean diameter of 6.4 (5.0, 9.4) cm for Case A, 4.4 (0.0, 7.3) cm for Case B, 5.2 (3.9, 7.3) cm for Case C, and a mean volume of 320 (167, 840) cm3 for Case A and 176 (60, 362) cm3 for Case C. The results indicate variability factors (95 percentile divided by 5 percentile values) in target diameters of 1.5 to 2.6, and in target lengths of 1.9 to 5.0. CONCLUSION: There was a substantial inconsistency in defining the planning target volume, both transversely and longitudinally, among radiation oncologists. The potential benefits of 3D treatment planning with high-precision dose delivery could be offset by this inconsistency in target-volume delineation by radiation oncologists. This may be particularly important for multicenter clinical trials, for which quality assurance of this step will be essential to the interpretation of results.

Aged↗

PubMed1998

Long-term follow-up of axillary node-positive breast cancer patients receiving adjuvant tamoxifen alone: patterns of recurrence.

PURPOSE: To determine the patterns, incidence and risk factors for local-regional recurrence in patients with Stage II and III breast cancer treated with adjuvant tamoxifen alone, without adjuvant radiation. MATERIAL AND METHODS: The records of patients referred to the London Regional Cancer Centre with a diagnosis of breast cancer between 1980-1989 were reviewed. During this time period, it was the policy of the institution to omit local-regional radiation to patients receiving adjuvant systemic therapy. One hundred and fifty axillary node-positive Stage II and III breast cancer patients received adjuvant tamoxifen alone without postoperative local-regional radiation; these patients form the basis of this report. RESULTS: Median follow-up was 67 months for the entire patient group and 85 months for the living patients. During this time, 42% of patients developed a recurrence, 22% first recurred in local-regional sites. The total incidence of local-regional recurrence (including those patients who first relapsed with systemic metastases) was 30%. Of the segmental mastectomy patients, 13% had recurrences in the intact breast. Of the modified radical mastectomy patients, 10% developed chest wall recurrences. Five percent of recurrences were first in the axilla and 6% in the supraclavicular nodes. Five-year actuarial survival for the entire patient group was 79% and disease-free survival was 60%, with a median disease-free survival time of 87 months. Five-year local-regional relapse-free survival was 76%. Five-year local-regional relapse-free survival was < 76% for those patients with 4 or more positive axillary nodes, regardless of tumor size. On univariable analysis, positive resection margins, number of positive axillary nodes, menopausal status, and negative estrogen and progesterone receptors were significant for isolated local-regional recurrence. On multivariable analysis, only positive resection margins and negative receptors remained significant. In terms of regional recurrence specifically, negative estrogen and progesterone-receptor status and positive resection margins were, again, prognostically significant. CONCLUSIONS: Postmenopausal women receiving adjuvant tamoxifen who have positive resection margins, > or = 4 positive axillary nodes and/or negative estrogen and progesterone receptors, are at higher risk of local and regional recurrence and should, therefore, receive local-regional radiation.

Adult↗