Steinar Tretli

Oncological outcomes after total mesorectal excision for cure for cancer of the lower rectum: Anterior vs. abdominoperineal resection

PURPOSE: This study was designed to examine the outcome of cancer of the lower rectum, particularly the rates of local recurrence and survival for tumors located in this area that have been treated by anterior or abdominoperineal resections. METHODS: A prospective, observational, national, cohort study which is part of the Norwegian Rectal Cancer Project. The present cohort includes all patients undergoing total mesorectal excision in 47 hospitals during the period November 1993 to December 1999. A total of 2,136 patients with rectal cancer within 12 cm of the anal verge were analyzed; there were 1,315 (62 percent) anterior resections and 821 (38 percent) abdominoperineal resections. The lower edge of the tumor was located 0 to 5 cm from the anal verge in 791 patients, 6 to 8 cm in 558 patients, and 9 to 12 cm in 787 patients. According to the TNM classification, there were 33 percent Stage I, 35 percent Stage II, and 32 percent Stage III. RESULTS: Univariate analyses: The five-year local recurrence rate was 15 percent in the lower level, 13 percent in the intermediate level, and 9 percent in the upper level (P = 0.014). It was 10 percent local recurrence after anterior resection and 15 percent after abdominoperineal resection (P = 0.008). The five-year survival rate was 59 percent in the lower level, 62 percent in the intermediate level, and 69 percent in the upper level (P < 0.001), respectively, and it was 68 percent in the anterior-resection group and 55 percent in the abdominoperineal-resection group (P < 0.001). Multivariate analyses: The level of the tumor influenced the risk of local recurrence (hazard ratio, 1.8; 95 percent confidence interval, 1.1–2.3), but the operative procedure, anterior resection vs. abdominoperineal resection, did not (hazard ratio, 1.2; 95 percent confidence interval, 0.7–1.8). On the contrary, operative procedure influenced survival (hazard ratio, 1.3; 95 percent confidence interval, 1–1.6), but tumor level did not (hazard ratio, 1.1; 95 percent confidence interval, 0.9–1.5). In addition to patient and tumor characteristics (T4 tumors), intraoperative bowel perforation and tumor involvement of the circumferential margin were identified as significant prognostic factors, which were more common in the lower rectum, explaining the inferior prognosis for tumors in this region. CONCLUSIONS: T4 tumors, R1 resections, and/or intraoperative perforation of the tumor or bowel wall are main features of low rectal cancers, causing inferior oncologic outcomes for tumors in this area. If surgery is optimized, preventing intraoperative perforation and involvement of the circumferential resection margin, the prognosis for cancers of the lower rectum seems not to be inherently different from that for tumors at higher levels. In that case, the level of the tumor or the type of resection will not be indicators for selecting patients for radiotherapy.

Vitamin D3 from sunlight may improve the prognosis of breast-, colon- and prostate cancer (Norway)

Objective: To investigate whether prognosis of breast-, colon- and prostate cancer may be related to vitamin D3, induced from solar ultra-violet (UV) radiation, through studies on geographical and seasonal variations in UV radiation. Methods: This study includes 115,096 cases of breast-, colon- or prostate cancer, diagnosed between 1964 and 1992. Among these, 45,667 deaths due to the cancer were registered. On the basis of a north–south gradient in solar UV radiation and geographical climatic differences, Norway was divided into eight residential regions. According to seasonal variations in UV radiation, four periods of diagnosis during the year were used. Case fatality according to residential region and to season of diagnosis was estimated using Cox regression. The effects of occupational sun exposure, childbearing pattern and educational level were also evaluated. Results: No geographic variation in case fatality was observed for the three cancer types studied. A significant variation in prognosis by season of diagnosis was observed. Diagnoses during summer and fall, the seasons with the highest level of vitamin D3, revealed the lowest risk of cancer death. Conclusion: The results suggest that a high level of vitamin D3 at the time of diagnosis, and thus, during cancer treatment, may improve prognosis of the three cancer types studied.

Height, body mass index, and prostate cancer: a follow-up of 950 000 Norwegian men

The present study explored body mass index (BMI), height, and risk of prostate cancer in a large Norwegian cohort of 950 000 men aged 20–74 years, whose height and weight were measured in a standardised way in the period 1963–1999. These were followed for an average of 21 years. The Cox proportional hazard models were used in the analyses. During follow-up, 33 300 histologically verified cases of prostate cancer were registered. The risk of prostate cancer increased by both BMI and height. The magnitude of the increase by BMI was modest, the relative risk (RR) of obese men (BMI⩾30) compared with normal weighted was 1.09 (95% CI: 1.04–1.15). However, the RR at age 50–59 years was 1.58 (95% CI: 1.29–1.94) in men being obese at about age 45 years compared with normal weighted men. The tallest men had an RR of 1.72 (95% CI: 1.46–2.04) compared with the shortest men. The overall effect of BMI on the incidence of prostate cancer was modest. The larger effect found in men aged 50–59 years might partly explain the previous inconsistent findings.

Blood Glucose and Risk of Incident and Fatal Cancer in the Metabolic Syndrome and Cancer Project (Me-Can): Analysis of Six Prospective Cohorts

Tanja Stocks and colleagues carry out an analysis of six European cohorts and confirm that abnormal glucose metabolism is linked with increased risk of cancer overall and at specific sites.

Esophageal and gastric carcinoma in Norway 1958-1992: Incidence time trend variability according to morphological subtypes and organ subsites

The occurrence of adenocarcinoma (AC) of the esophagus and gastric cardia has shown large increases in many but not all examined populations. This trend is in contrast with a decrease in distal gastric AC and a relative stability of esophageal squamous cell carcinoma. Our study aimed to describe esophageal and gastric carcinoma time trends in the Norwegian population between 1958 and 1992 based on data from the Cancer Registry of Norway. Estimated esophageal AC rates have accelerated over the study period, reaching average annual increases of 17% in men and 14% in women between 1983 and 1992. The occurrence of esophageal squamous cell carcinoma was relatively stable in both sexes. Proximal gastric cancer rates were stable in males and decreased somewhat in females. Distal gastric tumors showed decreases in both sexes, but were more pronounced in females. The strong increase in esophageal AC incidence parallels similar increases in the United States and some other countries. Although the observed increase may be explained to some extent by a shift in the classification of esophago‐cardial adenocarcinomas, the figures are compatible with a real increase. AC of the esophagus, the proximal stomach and the distal stomach exhibit different epidemiological features, both in terms of sex ratios and time trends, suggesting risk factor differences between the subsites. Int. J. Cancer 71:340‐344, 1997.

Smoking habits and risk of cancers other than lung cancer: 28 years' follow-up of 26,000 Norwegian men and women.

The impact of tobacco smoking on lung cancer risk has been investigated thoroughly since the 1950s, but other types of cancer also have been associated with smoking. In the present study, the aim was to explore the variation in risk connected with cigarette, cigar, and pipe smoking of suspected smoking-associated cancers other than lung cancer. Data were obtained from a survey of a random sample of the Norwegian population. A self-administered mailed questionnaire, which included questions about smoking habits, was completed by 26,000 men and women in 1965 (response rate: 76 percent). The cohort was followed from 1966 through 1993, including registration of all incident cancer cases. A dose-response relationship of cigarette smoking to the risk of urinary bladder cancer and cancers of the upper digestive and respiratory tract was observed. For the latter forms of cancer, a dose-response relationship of pipe smoking also was observed. In cancer of the pancreas, a stronger association between cigarette smoking and cancer risk was observed when the analysis was confined to histologically confirmed cases only. Current cigarette smokers at baseline had a significantly higher risk of cervical cancer than those who never smoked cigarettes. In cancers of the stomach, colon, rectum, breast, corpus uteri, ovary, and prostate, and in leukemia, no association between smoking and cancer risk was observed.

Risk Factors for Male Breast Cancer?A Case-Control Study from Scandinavia

We report a population-based case-control study on risk factors for male breast cancer. Data on a broad range of previously suggested risk factors were collected in a set of Scandinavian breast cancer cases and matched controls. Incident cases (n = 282) with histologically verified carcinomas of the breast were identified from notification to the cancer registries of Denmark, Norway and Sweden over a 4-year period 1987-1991 and of these cases, 156 men could be approached and responded. Controls were identified through national central population registers and were matched individually for country, sex and year of birth. Controls with a diagnosis of breast cancer were excluded; 468 of 780 controls responded. Data on risk factors were collected by self-administered questionnaires mailed to the cases between land 2 years after diagnosis and to controls during the same period. The findings were compatible with an increased risk associated with family history of breast cancer (odds ratio (OR) = 3.3, 95% confidence interval (CI) 2.0-5.6), obesity 10 years before diagnosis (OR = 2.1, 95% CI 1.0-4.5) for BMI > 30, diabetes (OR = 2.6, 95% CI 1.3-5.3) and the use of digoxin and methyldopa (OR = 2.0 and 2.1, respectively). The association with family history of breast cancer has been repeated in several studies, while the relation to anthropometric measures has been equivocal. We could not substantiate some associations seen in other studies; namely those with high education, fertility, marital status, testicular injury, liver disease and religion. The detailed questions about gynaecomastia indicated that many cases reported signs of breast cancer as a gynaecomastia. This type of misunderstanding may explain the strong association with gynaecomastia seen in other studies. Several patients died before contact. Thus, risk factors related to a more aggressive male breast cancer or related to high risk of dying (e.g. liver cirrhosis, heavy smoking) may have been missed.

Association between serum 25(OH)D and death from prostate cancer

Based on observations that for certain cancers, mortality varies according to sun exposure, vitamin D has been proposed to influence on disease progression. This study aims to investigate whether serum levels of 25(OH)D are associated with prognosis in patients with prostate cancer. In total, 160 patients with a serum sample in the JANUS serum bank were included. For 123 patients a pre-treatment serum sample was taken, whereas 37 of the patients had received hormone therapy prior to the blood collection. The serum level of 25(OH)D was classified as low (< 50 nmol l−1), medium (50–80 nmol l−1) or high (>80 nmol l−1). A Cox proportional hazard regression model was used to assess the association between serum 25(OH)D and cancer mortality. During follow-up, 61 deaths occurred, of whom 52 died of prostate cancer. The median time of follow-up was 44.0 months (range, 1.2–154.6). Serum 25(OH)D at medium or high levels were significantly related to better prognosis (RR 0.33; 95% CI 0.14–0.77, RR 0.16; 95% CI 0.05–0.43) compared with the low level. Analysis restricted to patients receiving hormone therapy gave a stronger association. The serum level of 25(OH)D may be involved in disease progression and is a potential marker of prognosis in patients with prostate cancer.

Effect of hospital caseload on long-term outcome after standardization of rectal cancer surgery at a national level

The purpose of this prospective study was to examine the influence of hospital caseload on long‐term outcome following standardization of rectal cancer surgery at a national level.

Lifestyle changes during adolescence and risk of breast cancer: An ecologic study of the effect of World War II in Norway

There are biologic reasons to believe that the period between thelarche and the first full-term pregnancy is a particularly sensitive period in a womans life regarding the development of breast cancer. In this ecologic study, data provided by the Norwegian Cancer Registry were analyzed to compare risk of breast cancer among women who experienced this sensitive period before, during, or after World War II. An ordinary age-cohort model and a model where the cohort was described by exposure by calendar period and sensitivity to this exposure at different ages, were fitted to the data. The incidence of breast cancer was lower than expected among women who experienced puberty during the war. The estimated configuration of the exposure variable showed an increase in exposure up to the start of WWII to twice the levelin 1916, dropped by 13 percent during the war, and increased again after the war. The levelin 1975 was approximately 2.7 times higher than the level in 1916. The results indicate that one or more lifestyle factors that changed among adolescent women during the war, influenced their risk of breast cancer. Dietary intake of energy, fat, meat, milk, fish, fresh vegetables, and potatoes, in addition to physical activity level and height, are important factors to consider in relation to breast cancer risk.