Biomedical subjects

Petronella G M Peer

Publications and source records attributed to Petronella G M Peer.

6 recordsLinked to original sources

PubMed2006

Risk factors for non-sentinel lymph node metastases in patients with breast cancer. The outcome of a multi-institutional study.

BACKGROUND: In this multi-institutional prospective study, we evaluated whether we could identify risk factors predictive for non-sentinel lymph node (non-SN) metastases in breast cancer patients with a positive sentinel lymph node (SN). METHODS: In this multi-institutional study, 541 eligible breast cancer patients were included prospectively. RESULTS: The occurrence of non-SN metastases was related to the size of the SN metastasis (P = .02), primary tumor size (P = .001), and lymphovascular invasion (P = .07). The adjusted odds ratio was 3.1 for SN micro-metastasis compared with SN isolated tumor cells, 4.0 for SN macro-metastasis versus SN isolated tumor cells, 3.1 for tumor size (>3.0 cm compared with </=3.0 cm), and 2.0 for lymphovascular invasion (yes versus no). There were no positive non-SNs when the primary tumor size was </=1.0 cm (n = 24) [95% confidence interval (95% CI) 0%-14.0%]. The proportion of positive non-SNs ranged in a prognostic logistic regression model from 9.7% (95% CI 4.0%-23.0%) for patients with SN isolated tumor cells, tumor size of 1.1-3.0 cm, and without vessel invasion, to 72.6% (95% CI 47.0%-89.0%) for patients with SN macro-metastasis, tumor size >3.0 cm, and with vessel invasion. CONCLUSION: We identified three predictive factors for non-SN metastases in breast cancer patients with a positive SN: size of the SN metastasis; primary tumor size; and vessel invasion. We were not able to identify a specific group of patients with a positive SN in whom the risk for non-SN metastases was less than 5%.

Adult↗

PubMed2006

Differences in sentinel lymph node pathology protocols lead to differences in surgical strategy in breast cancer patients.

BACKGROUND: Internationally, there is no consensus on the pathology protocol to be used to examine the sentinel lymph node (SN). At present, therefore, various hospitals use different SN pathology protocols of which the effect has not been fully elucidated. We hypothesized that differences between hospitals in SN pathology protocols affect subsequent surgical treatment strategies. METHODS: Patients from four hospitals (A-D) were prospectively registered when they underwent an SN biopsy. In hospitals A, B, and C, three levels of the SN were examined pathologically, whereas in hospital D, at least seven additional levels were examined. In the absence of apparent metastases with hematoxylin and eosin examination, immunohistochemical examination was performed in all four hospitals. RESULTS: In total, 541 eligible patients were included. In hospital D, more patients were diagnosed with a positive SN (P < .001) as compared with hospitals A, B, and C, mainly because of increased detection of isolated tumor cells. This led to more completion axillary lymph node dissections in hospital D (66.3% of patients (P < .0001), compared with 29.0% in hospitals A, B, and C combined). Positive non-SNs were detected in 13.9% of patients in hospital D, compared with 9.7% in hospitals A, B, and C (P = .70). That is, in 52.4% of patients in hospital D, a negative completion axillary lymph node dissection was performed, compared with 19.3% of patients in hospitals A, B, and C combined. CONCLUSIONS: Differences in SN pathology protocols between hospitals do have a substantial effect on SN findings and subsequent surgical treatment strategies. Whether ultrastaging and, thus, additional surgery can offer better survival remains to be determined.

Adult↗

PubMed2005

Myo-inositol, glucose and zinc concentrations determined in the preconceptional period, during and after pregnancy.

OBJECTIVE: To determine the blood concentrations of myo-inositol, glucose and zinc before, during and after normal pregnancy. STUDY DESIGN: Preconceptionally, at 6, 10, 20, 30 and 37 weeks amenorrhea, and 6 weeks after delivery, blood samples of 18 nulliparae and 19 multiparae were obtained and concentrations of serum inositol and glucose, and red blood cell zinc were determined. The data were analyzed using a linear mixed model. RESULTS: The preconceptional mean (S.E.M.) inositol concentration of 21.7 (1.03) micromol/L was comparable to the concentrations at 6 and 37 weeks amenorrhea, 22.2 (1.03) micromol/L, and 19.9 (1.10) micromol/L, respectively. However, the inositol concentrations at 10 and 20 weeks amenorrhea and post partum were significantly lower than the preconceptional inositol concentration, p<0.05. The preconceptional mean (S.E.M.) glucose concentration of 3.9 (1.03) mmol/L was comparable to the concentration at 6 and 10 weeks amenorrhea, 3.9 (1.04) mmol/L and 3.8 (1.04) mmol/L respectively. Also at 20, 30 and 37 weeks amenorrhea and after delivery the glucose concentration was significantly lower than the preconceptional glucose concentration, p<0.05. Preconceptional red blood cell zinc concentrations were comparable to concentrations at 6, 10 and 20 weeks amenorrhea. At 30 and 37 weeks amenorrhea and post partum the zinc concentrations were significantly higher than in the preconceptional period (p<0.01). CONCLUSION: The concentrations of inositol, glucose and zinc significantly change during pregnancy. However, the preconceptional blood concentrations reflect the concentrations determined in the first pregnancy trimester rather well, which is important information to be used in future studies into the role of inositol, glucose and zinc in reproductive disorders.

Adult↗

PubMed2004

Estimating life expectancy and related probabilities in screen-detected breast cancer patients with restricted follow-up information.

Issues such as life expectancy after diagnosis, the number of life years gained by early diagnosis through screening, the probability of dying from breast cancer or of dying from other causes during the lead time period or thereafter can be derived from information on complete survival after diagnosis. A method is presented to estimate complete survival and relevant outcomes after diagnosis of screen-detected cancer when the follow-up period is substantially shorter than the maximum follow-up possible. Survival after diagnosis until death from breast cancer is modelled as the sum of the lead time (LT) and the post-lead time (PLT), where both time periods follow exponential distributions and are assumed to be independent. The survival period after diagnosis until death from causes other than breast cancer (X) is assumed to follow a Gompertz distribution. The survival period after diagnosis until death from any cause (Z) is modelled as the minimum of LT+PLT and X. Maximum likelihood methods were then used to estimate all parameters of Z. This procedure for obtaining maximum likelihood estimates of Z does not need the cause of death (breast cancer or other), which is an advantage over most other methods. Especially in older patients, it may be difficult or even impossible to ascertain the true cause of death. The model was applied to data from the long-term breast cancer screening programme in Nijmegen, the Netherlands. Complete survival was estimated on the basis of survival data on 528 screen-detected breast cancer patients, diagnosed in 1975-1997 and with a mean follow-up of 8.9 years. Estimated life expectancy ranged between 22.3 and 9.0 years for patients diagnosed at the age of 50 and 79 years, respectively, that is, 6.1 and 0.7 life years gained by screening. Through early diagnosis and treatment, screen-detected patients diagnosed at the age of 50 years may have reduced their lifetime risk of dying from breast cancer from 79 per cent to 56 per cent; at the age of 79 the reduction of risk is reduced from 23 per cent to 13 per cent.

Aged↗

PubMed2004

Marginal maternal vitamin B12 status increases the risk of offspring with spina bifida.

OBJECTIVE: The purpose of this study was to investigate B vitamins and homocysteine as risk factor for offspring with spina bifida. STUDY DESIGN: Blood samples from 45 mothers and their children with spina bifida and from 83 control mothers and their children were obtained to determine the levels of serum and red blood cell folate, serum vitamin B(12), whole blood vitamin B(6), and total plasma homocysteine. RESULTS: In the case mothers, the vitamin B(12) concentration was 21% lower (95% CI, 8%-33%) compared with control mothers. Unlike folate, vitamin B(6,) and homocysteine, a vitamin B(12) concentration of <or=185 pmol/L was associated with a 3.5-fold (95% CI, 1.3- 8.9) spina bifida risk. In children, no differences in folate, vitamin B(6), vitamin B(12), and homocysteine concentrations were observed after adjustment for the child's age. CONCLUSION: A marginal maternal vitamin B(12) status increases the risk of an offspring with spina bifida.

Case-Control Studies↗

PubMed2004

Low maternal dietary intakes of iron, magnesium, and niacin are associated with spina bifida in the offspring.

Evidence about the preventive effects of nutrients other than folate on the occurrence of spina bifida is scarce. Therefore, the aim of this work was to investigate the role of maternal nutritional intake and the risk of spina bifida in the offspring. In 106 cases and 181 controls, the mothers' nutrient intakes were obtained by an FFQ approximately 24 mo after conception of the index pregnancy. Energy-adjusted mean nutrient intakes were compared, and odds ratios (OR) and 95% CI were calculated. Although mean nutrient intakes were comparable to the Dutch food consumption survey data, fat, cholesterol, iron, and folate intakes were below the 1998 Dutch Recommended Daily Allowances. Case mothers had significantly lower intakes of plant proteins (7%), polysaccharides (4%), fiber (7%), iron (6%), magnesium (6%), and niacin (4%) than control mothers. Mono- and disaccharide intakes were significantly higher (6%) in the case mothers than in control mothers. The adjusted OR (95% CI) in the lowest quartiles for plant proteins was 5.4 (2.3-12.4), for fiber 3.1 (1.5-6.8), for iron 3.5 (1.4-8.3), for magnesium 1.9 (0.9-4.1), and for niacin 2.5 (1.2-5.2). Mono- and disaccharide and polysaccharide intakes in the highest quartile had ORs (95% CI) of 2.9 (1.4-6.3) and 0.5 (0.3-1.0), respectively. The nutritional intake of Dutch women from food groups containing iron and folate seems to be compromised. Low preconceptional intakes of plant proteins, iron, magnesium, and niacin are associated with a 2- to 5-fold increased risk of spina bifida.

Adult↗