Restaging of breast cancer in a northern Alberta registry.

All breast cancer patients presenting preoperatively at the Dr. W.W. Cross Cancer Institute, Edmonton, since 1971 are included in a registry that provides detailed clinical and epidemiologic information on the nature of this disease in northern Alberta. For the 141 female patients who were seen preoperatively in 1971 and thereafter followed regularly, disease was restaged according to the 1973 revision of the tumour-nodes-metastases (TNM) formula of Union internationale contre le cancer (UICC) to permit comparison with staging according to the 1968 formula. The staging distribution was altered greatly because of major changes in the staging system. With the 1973 revision stage II includes disease without palpable lymph nodes and greater emphasis is placed on tumour size. Accurate preoperative staging and registration are essential for meaningful statistics and as an aid in patient management.     

Bilateral breast cancer in northern Alberta: risk factors and survival patterns.

Of 2231 women with stage I, II or III breast cancer who were registered and seen between 1971 and 1979 and followed to the end of 1981, 48 (2.2%) had synchronous and 58 (2.6%) asynchronous bilateral breast cancer. The unadjusted incidence rate for a second breast cancer was 6.4/1000 breast-years at risk, compared with a rate of 0.70 for the risk of a first breast cancer in women. When calculated from the date of diagnosis of the first breast cancer the survival rate was better for the group with asynchronous disease than for the group with synchronous disease or for a group with unilateral disease, but when calculated from the date of diagnosis of the second cancer the rate was the same in all three groups. Comparison of known risk factors showed a significant association between the development of bilateral cancer and a later age at the birth of the first child and a longer interval between menarche and that birth. There was a trend towards greater age and more stage III cancer in the group with synchronous disease. There was no correlation between receiving radiotherapy for the first breast cancer and development of the second cancer. Annual mammography and clinical examination of asymptomatic women at a cancer centre resulted in the detection of a significantly higher proportion of minimal breast cancers in the second breast compared with the first. Such screening practices should be even more valuable in the earlier detection of unilateral breast cancer in asymptomatic women who have not had breast cancer.     

Five-year survival of women with breast cancer in northern Alberta.

Five-year survival rates for all 519 women with breast carcinoma in northern Alberta in 1971 and 1972 were analysed with the use of data from the computerized northern Alberta breast registry and the Alberta cancer registry. The relative 5-year survival was 73%, which is higher than most rates reported from other centres. Lymph node involvement was significant as a prognostic factor, with the relative 5-year survival falling from 92% in the group without lymph node involvement to 58% in the group with three or more involved nodes. The prognosis was also significantly affected by the stage of the disease according to the 1973 TNM classification: the 5-year survival rates ranged from 88% for patients with stage 1 disease to 17% for those with stage IV disease. Women 40 to 59 years of age had a higher survival rate (79%) than those under 40 years (65%) or over 60 years (66%) of age. Analyses by 5-year age groups showed that women 35 to 39 years old had a particularly poor survival rate (59%). Postmenopausal women less than 55 years old had a higher survival rate than did perimenopausal or premenopausal women in the same age group. Further follow-up is indicated to correlate possible high-risk factors with survival.     

Reproductive events and family history as risk factors for breast cancer in northern Alberta.

Reproductive events and family history as risk factors for breast cancer in northern Alberta were investigated with the use of data from a computerized population-based registry. Women aged 30 to 79 years attending diagnostic breast clinics at the Cross Cancer Institute from 1971 through 1975 constituted the two study groups; 1232 women had diagnosed breast cancer (malignant disease group) and 602 women were clinically free of all types of breast disease (control group). An increased relative risk of breast cancer was found in women with a family history of breast cancer, those who gave birth to their first term infant at age 30 years or older, those in whom more than 15 years elapsed between menarche and that birth, and those with a late natural menopause. There was a decreased risk, relative to nulliparity, in the postmenopausal women who first gave birth to a term infant 5 years or less after menarche. Artificial menopause (bilateral oophorectomy), parity and age at menarche had no apparent effect on the risk. The pattern of risk factors in northern Alberta differed from that reported for other geographic areas, including other provinces of Canada, thus emphasizing the need for local studies in the planning of screening programs.     

Breast cancer and oral contraceptives: findings in Oxford-Family Planning Association contraceptive study.

Among the 17 032 women taking part in the Oxford-Family Planning Association contraceptive study, 72 were first diagnosed as having breast cancer between the date they were admitted to the study and 1 September 1980. The relative risk of developing the disease in women who had used oral contraceptives in comparison with those who had never used them was estimated to be 0.96 (95% confidence limits 0.59 to 1.63). Among women aged under 35 years, the corresponding relative risk (based on only 14 women with breast cancer) was estimated to be 0.61. No relation was apparent between the risk of developing breast cancer and duration of oral-contraceptive use or interval since first oral-contraceptive use in any age group. The data in this study are thus reassuring; but observations based on women with long-term use of oral contraceptives, especially those starting to use the preparations at an early age, are few.     

Colpohistologic correlations. A computerized study

Data from 300 colposcopic cases were computerized to study the correlations between the colposcopic observations and the histologic and other data. Colposcopy was shown to be most useful in women under 35 years of age. Use of oral contraceptives (the Pill) seemed to relate to a higher level of successful colposcopic visualization and may even prevent the need for conization, based on a higher incidence of negative endocervical curettages. Although 14.5% of the cases were colposcopically undergraded and 17% overgraded when compared to the histopathology, the histologic predictability of the colposcopic observation of white epithelium and vascular changes (punctation and mosaicism) was excellent. Colposcopy remains an essential technique in the appraisal and management of cervical intraepithelial neoplasia.     

Breast cancer and oral contraceptives: findings in Royal College of General Practitioners' study.

The incidence of breast cancer was studied among women taking part in the continuing cohort study organised by the Royal College of General Practitioners. An overall relative risk of 1.19 (not significant) was found in those who had used oral contraceptives. The risk ratio in women under 35 years old was 2.81, but this too was not significant. There was evidence that the estimated increased risk for younger women could be a chance occurrence. No convincing evidence of any adverse effects of oral contraceptives on breast cancer has been shown, but because of the long latent period of this tumour there is a need for longer observation.     

Ginkgo biloba in dyslexia: a pilot study.

OBJECTIVES: The purpose of this study was to collect preliminary information on the possible efficacy and tolerability of EGb 761 standardized plant extract of Ginkgo biloba as a treatment of dyslexia in school-aged children. METHODS: Fifteen children (5-16 year old) with dyslexia participated in an open-label trial of EGb 761 given as a single morning dose of 80 mg. Standardized tests for dyslexia were administered at baseline and at the end of the study. RESULTS: All 15 children completed the trial. The score of the standardized tests for dyslexia decreased. On the list of words the score decreased from mean 4.33 (SD=2.37) at baseline to 2.66 (SD=1.58) at the end of the study (p<0.01), on the list of non-words from mean 3.39 (SD=1.5) at baseline to 2.26 (SD=0.92) at the end of the study (p<0.02) and on the reading piece from mean 3.52 (SD=2.11) to 2.13 (SD=1.25); at the end of the study (p<0.05). At the end of the study 9 children did not perform below the -2 SD on the list of words and 7 on reading text and so they no longer fulfilled the DSM-IV-TR criteria for dyslexia. A brief period of headache was reported by the parents of two children. CONCLUSION: These data suggest that EGb 761 standardized plant extract of Ginkgo biloba has acceptable acute tolerability at single doses up to 80 mg/day and is possibly efficacious in decreasing dyslexia difficulties. The need for a double-blind trial is discussed by the authors.     

Spatial and temporal variations in boreal forest fire frequency in northern Alberta

Abstract. Spatial and temporal variations in fire frequency in the boreal forest of Wood Buffalo National Park (WBNP) were assessed using forest stand age, fire scar and historical data. I test the hypotheses that (1) fire frequency is higher in jack pine forests and aspen forests than in black spruce forests and white spruce forests, (2) these variations in fire frequency can be related to the mean waterbreak distance (MWD) around a site and (3) fire frequency has changed over the past 300 years. The fire cycles (the time required to burn an area equal in size to the entire study area) in jack pine forests (39 years) and in aspen forests (39 years) were significantly shorter than those in black spruce forests (78 years) and in white spruce forests (96 years). The length of the fire cycle varies inversely with the MWD around a site, and the MWD was significantly higher in jack pine and aspen forests than in black or white spruce forests. It is suggested that covariations between soil type and the MWD influence, respectively, variations in forest dominant and fire frequency. A change in fire frequency at 1860 was apparent in the fire history for all of WBNP, the black spruce dominated stands, and the near and medium MWD classes. The fire cycle estimates for these classes were all significantly shorter during the period 1750 to 1859 (fire cycles = 25–49 years) than they were in the period 1860 to 1989 (fire cycles = 59–89 years). The possible roles of changes in climate and aboriginal burning practices in causing the temporal change in fire frequency are discussed.