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P Kenemans

Publications and source records attributed to P Kenemans.

At least 109 records · Page 6Linked to original sources
PubMed1997

Hormone replacement therapy and cardioprotection: basic concepts and clinical considerations.

A large body of epidemiological evidence shows that estrogen use after the menopause reduces the incidence of cardiovascular disease up to 50%. The use of progestin as co-medication in HRT appears not to attenuate the cardioprotective effects of estrogen. Menopause-related changes in metabolic cardiovascular risk factors are identifiable, as are HRT-related changes in these factors. Estrogens may act in a gender-specific way on vascular endothelial cells and other components of the vessel wall enhancing the synthesis and release of NO and other vasodilators and by inhibiting the synthesis and release of vasoconstricting agents, thus favoring vasodilation. Angiographic studies demonstrated in postmenopausal women with ischemic heart disease a reduction in coronary stenosis by estrogen monotherapy. Several studies, including the PEPI-trial, failed to demonstrate any major effect of HRT on blood pressure. The information on HRT and cardioprotection which is available so far is very promising and merits recommending HRT not only in healthy women but also in women with cardiovascular disease as well as in women with increased risk for this disease.

Blood Pressure↗
PubMed1997

Hormone replacement therapy and breast cancer morbidity, mortality and recurrence.

The effects of short-term and long-term HRT (in its various forms, unopposed oestrogens, sequentially combined HRT and continuous combined HRT) on the female breast are reviewed. The question is addressed whether HRT will increase the risk of breast cancer as well as the risk of dying from breast cancer in healthy women, and whether or not women who already run an increased risk on the basis of a positive family history, use of DES during pregnancy or because of the presence of premalignant epithelial abnormalities in the breast, increase their risk for breast cancer further. The risks of HRT and the options for HRT in patients who have a history of breast cancer are discussed and alternative treatment modalities for climacteric complaints (e.g. clonidine, paced-respiration) or for preventive HRT (e.g. tamoxifen, tibolone) are reviewed.

Breast Neoplasms↗
PubMed1997

Intraperitoneal photodynamic therapy: comparison of red and green light distribution and toxicity.

The aim of this study was to compare red (652 nm) and green (514 nm) light for photodynamic therapy (PDT) of the peritoneal cavity with emphasis on light distribution and toxicity. Red-light PDT was limited by intestinal toxicity and it was hypothesized that less penetrating green light would allow higher light doses to be used in the peritoneal cavity. Female non-tumor-bearing rats were photosensitized with mTHPC (meta-tetrahydroxyphenylchlorin, Foscan) intravenously or intraperitoneally and the peritoneum was illuminated using a minimally invasive technique. For both red and green light, the time of illumination was varied to give the required dose. Light fluence rate was measured in situ at multiple sites within the abdominal cavity. The toxicity experiments were carried out with a total of 160 J incident red or 640 J incident green light and a drug dose of 0.15 mg/kg Foscan. For red light a mean fluence rate of 55.2 +/- 38.5 mW cm-2 was measured, with a peak fluence rate of 128 mW cm-2 on the intestines. For green light the mean and peak fluence rates were 8.2 +/- 9.0 (i.e. including zero fluence rate measurements) and 28 mW cm-2, respectively. Intestines were most vulnerable to red light illumination. The intravenous injection route resulted in increased toxicity for red light, but for green light there were no major differences between intravenous and intraperitoneal routes. The 4 h interval between drug and illumination resulted in very little toxicity for both wavelengths. We conclude that for intraperitoneal PDT green light allows higher light doses than red light, but the light distribution over the peritoneum is much less favorable and may not be suitable for whole peritoneal illumination using a minimal-access technique.

Animals↗
PubMed1997

Oral 17 beta-estradiol continuously combined with dydrogesterone lowers serum lipoprotein(a) concentrations in healthy postmenopausal women.

Lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerosis. Serum Lp(a) concentrations increase after menopause, and postmenopausal estrogen replacement appears to decrease Lp(a) levels. In a randomized, double blind study, we examined the effects of 6-month treatment with daily 17 beta-estradiol (E2; 2 mg, orally) continuously combined with one of four dosages [2.5 mg (n = 41), 5 mg (n = 38), 10 mg (n = 38), and 15 mg (n = 20)] of dydrogesterone on fasting serum Lp(a) concentrations in 137 healthy postmenopausal women. At baseline, no significant differences were noted among the four treatment groups. During the study period of 6 months the median serum Lp(a) concentration decreased significantly from 128 mg/L (range, 5-1660) to 110 mg/L (range, 1-1530) in the total population, corresponding to a reduction of 13% (P < 0.001). The percent changes in serum Lp(a) correlated positively with the percent changes in serum E2 at 3 as well as 6 months of therapy (r = 0.38; P < 0.001 and r = 0.35; P < 0.001, respectively). A dose response of dydrogesterone on serum Lp(a) was not found. In addition, serum lipids and (apo)lipoproteins improved significantly in all four treatment groups. In conclusion, oral E2 continuously combined with dydrogesterone has beneficial effects on the lipid and lipoprotein profile and is effective in lowering Lp(a) concentrations in postmenopausal women.

Apolipoproteins↗
PubMed1997

Clinical evaluation of the Byk LIA-mat CA125 II assay: discussion of a reference value.

The Byk LIA-mat CA125 II assay was compared with the Centocor IRMA CA125 II. Serum samples studied (n = 1012) were obtained from 652 apparently healthy females, 61 pregnant women, and 299 patients with benign and malignant gynecological tumors. The CA125 II assay value at the 95th percentile of the total healthy group was 29 kU/L for the LIA-mat and 32 kU/L for the Centocor assay. For the LIA-mat assay the 95th percentile was 31 kU/L (Centocor 36 kU/L) for the group < 45 years and 21 kU/L (Centocor 25 kU/L) for women > 55 years of age. By using ROC curves we found the optimal pretreatment Byk LIA-mat CA125 II value differentiating between benign and malignant ovarian tumors to be 95 kU/L. Pretreatment CA125 values > 1000 kU/L were detected in serum samples of patients with advanced epithelial ovarian cancer.

Adolescent↗
PubMed1997

Clinical and technical evaluation of ACS BR serum assay of MUC1 gene-derived glycoprotein in breast cancer, and comparison with CA 15-3 assays.

The mucin glycoprotein-detecting assay CA 15-3 is a valuable tool for monitoring the course of disease in breast cancer patients. Assays of CA 15-3 are based on the use of two MAbs to polymorphic epithelial mucin (PEM). We evaluated the technical and clinical performance of the Chiron ACS BR, an automated competitive chemiluminescence assay using a single MAb, B27.29, and compared the assay's results with those of the Centocor CA 15-3 RIA, the Abbott IMx CA 15-3, and the Boehringer Mannheim Enzymun-Test CA 15-3. The study population consisted of 253 healthy women, 66 patients with benign breast disease, 168 breast cancer patients, and 76 patients with other carcinomas. In the technical evaluation, we assessed the precision and linearity on dilution of the ACS BR assay. Cutoff values (upper limits of values seen in healthy subjects) were determined for all four assays. Agreement between the assays was studied by linear regression analysis. The ACS BR assay gave within- and between-assay CVs of 2.2% and 3.9%, respectively. Three samples from healthy women gave discordant values by ACS BR and were not included in the calculations. All four assays exhibit a highly similar pattern when monitoring breast cancer disease; the closest agreement of values was obtained between ACS BR and Centocor CA 15-3. We conclude that the ACS BR assay is a fast and reliable immunoassay for measuring PEM in serum. Although it detects a slightly different epitope on the PEM molecule than is targeted in other assays, for cancer serum samples it agreed better with the original Centocor CA 15-3 assay than did the other two CA 15-3 assays tested.

Adolescent↗
PubMed1996

PCR-based high-risk HPV test in cervical cancer screening gives objective risk assessment of women with cytomorphologically normal cervical smears.

Cervical-cancer screening programmes using cytomorphological criteria could be more efficient if the screening included objective individual risk factors for women with normal cytology, such as a test for high-risk human papillomavirus (HPV). The value of a PCR-based test for high-risk HPV types was studied in a cohort of 1622 women presenting in a routine triannual population-based screening programme. Women were included in the study when they had no previous history of cervical dysplasia; and their initial Pap smear was read as normal (Pap 1 or 2). The mean age of the women was 42 years (range 34-54 years) and mean follow-up time was 40 months (range 5-73 months). Women were referred for colposcopically directed biopsies if they had had 2 successive cervical smears read as Pap 3a (mild to moderate dyskaryosis) or one read as > or = Pap 3b (severe dyskaryosis). Women with histologically confirmed cervical intraepithelial neoplasia grade III (CIN III) were considered positive cases. All women were tested for 14 high-risk HPV genotypes. Of the 86 high-risk HPV-positive women, 6 developed CIN III, whereas only 1 of the 1536 HPV-negative women did. The women with normal Pap smears containing high-risk HPV genotypes were 116 times (95% CI, 13-990) more at risk of developing CIN III, in contrast to women without high-risk HPV. These results support the view that the interval between successive smears in cervical-cancer screening can be increased considerably for women with cytomorphologically normal and high-risk HPV-negative cervical smears as determined by PCR.

Adult↗
PubMed1996

Biodistribution of (111)indium-labeled engineered human antibody CTMO1 in ovarian cancer patients: influence of protein dose.

Thirty-one patients suspected of having ovarian cancer received a single i.v. injection of radiolabeled (100 MBq (111)In) engineered human CTMO1 (hCTMO1) to investigate its potential as an internalizing drug carrier. hCTMO1 is a complementary-determining region-grafted human IgG4 monoclonal antibody recognizing an ovarian carcinoma-associated antigen, the MUC-1-gene product. The amount of radioactivity was determined in tumor tissue, various normal tissues, including liver biopsies, and blood samples obtained at laparotomy, 6 days after injection of either 0.1 or 1.0 mg hCTMO1/kg of body weight. Circulating antigen-15-3 was measurable in all patients before injection, and immune complex formation was already present at the end of infusion. In the 0.1 mg/kg group, most of the radioactivity was bound to immune complexes, whereas in the 1.0 mg/kg group, most was bound to IgG monomers. Increasing the hCTMO1 dose 10-fold did not influence the overall disappearance of (111)In from the blood, but the elimination half-life of (111)indium bound to immune complexes was increased 2-fold. Uptake in tumor tissue 6 days postinjection at the 0.1 mg/kg dose was 7.6 times higher (P = 0.0009) than in normal tissue and 2.5 times higher (P = 0.03) than in blood. At the 1.0 mg/kg dose, the uptake in tumor tissue was 14.0 times higher (P = 0.0003) than in normal tissue and 8.1 times higher (P = 0.0007) than in blood. Liver activity was substantial (23.7 +/- 10.5 and 18.3 +/- 6.7% of the injected dose/kg for the 0.1 and 1.0 mg/kg dose group, respectively). These results are superior to those found with other clinically tested anti-MUC-1 gene product antibodies. hCTMO1 seems to be a suitable carrier for cytotoxic agents in ovarian carcinoma patients; the better uptake results and tumor-to-blood ratios are obtained at the higher dose of 1.0 mg hCTMO1/kg body weight.

Adult↗
PubMed1996

CA 125: a valid marker in ovarian carcinoma patients treated with paclitaxel?

BACKGROUND: Changes in serum CA 125 from baseline do not reflect response to paclitaxel in relapsed ovarian carcinoma patients. Our study aimed to determine whether CA 125 changes relate to tumor response and overall survival during paclitaxel salvage treatment. METHODS: Response data and CA 125 values of 77 platinum pretreated ovarian carcinoma patients were included in the study. Patients received 496 courses of paclitaxel in total (median 6; range: 2-18 courses). RESULTS: Response group numbers on the basis of World Health Organization (WHO) criteria were: 7 partial response, 22 stable disease, and 48 progressive disease. CA 125 values at the moment of clinical response allocation, the median survival duration, and the 3-year survival rate did not differ among WHO defined response groups. For both the stable disease group and the responders, the slopes of the exponential CA 125 regression curves during paclitaxel treatment were negative. Response groups, as defined by CA 125 changes, i.e., halving or doubling of baseline values, after 4 courses were concordant with WHO defined response groups in only 27%, but predicted survival far better. CONCLUSIONS: This study confirms that CA 125 changes in patients receiving paclitaxel treatment do not correlate with response allocations according to WHO criteria. In particular, patients with clinically and radiologically defined progression will often not show an increase in CA 125 concentrations from baseline. Those patients who do show doubling of CA 125 values, however, have a very poor prognosis. The CA 125 ratio, as determined after 4 courses of paclitaxel treatment, may be a better indicator of response than WHO defined response status.

Antineoplastic Agents, Phytogenic↗
PubMed1996

LHRH agonist treatment of breast cancer and gynecological malignancies: a review.

Since 1982 LHRH agonists have been used as a treatment modality in patients with disseminated breast cancer and gynecologic malignancies, based on the assumption of steroid dependence of these cancers. They have been successfully used in the treatment of premenopausal women with breast cancer; response rates reported are 31-63%. Less optimistic results have been reported in postmenopausal breast cancer patients as well as in the treatment of women suffering from ovarian cancer. Response rates for treatment of postmenopausal breast- and ovarian cancer patients appear to be up to 22% and 29%, respectively. Studies using LHRH agonists to treat endometrial and cervical intra-epithelial neoplasia are still rare and, until now, no data about the efficacy of LHRH agonists in treating these malignancies have been reported. This paper reviews clinically important studies of LHRH agonists, including a rationale for the use of LHRH agonists in breast cancer and gynecological cancer treatment. In view of the changed endocrine state in postmenopausal women on the one hand and alterations in endocrine metabolism in breast cancer tissue on the other hand, it is concluded that it might be more effective to use a combination of LHRH agonists and other endocrine modalities to treat disseminated breast cancer and gynecological malignancies.

Breast Neoplasms↗
PubMed1996

Endometrial response in estrogen replacement therapy quarterly combined with a progestogen.

OBJECTIVE: The aim of the study was to investigate the endometrial histology and the bleeding pattern under a hormone replacement therapy regimen with continuous estrogen quarterly (3-monthly) combined with a progestogen. METHODS: In a prospective, double-blind, randomised clinical trial, 30 healthy, postmenopausal women were allocated to one of the three trial preparations. Group I was treated with 1 mg micronized 17 beta-estradiol continuously, group II took 2 mg micronized 17 beta-estradiol continuously and group III took 1 mg and 2 mg 17 beta-estradiol alternating every 42 days (step-up regimen). One treatment cycle was 84 days, during the last 12 days estradiol was combined with 50 micrograms gestodene. The total treatment period comprised two cycles of 12 weeks each. With regard to endometrial histology, the second cycle was the actual study cycle. In each patient endometrial samples were obtained at the following time points: after the withdrawal bleeding in the beginning (day 8-11) of cycle II (Vabra-method), at the end of the estrogen mono-phase (day 70-72) of cycle II(Pipelle-method), and 8-11 days after cessation of all medication (Vabra-method). Histopathological classification was done by two experienced gynaecological pathologists. All patients kept record of their bleeding events in a diary. Analysis of variance and Kruskal-Wallis test were used for statistical analysis of the data. RESULTS: 29 patients were evaluable for the assessment of endometrial histology. Only one sampling procedure (1.2%) yielded an insufficient amount of tissue. In each treatment group, simple (cystic) hyperplasia was observed exclusively at the end of the estrogen mono-phase (in total 4/29 patients, 14.8%). Hyperplasia disappeared in all cases after the combined estrogen-progestogen phase. No cytological atypia was seen. Fifty-five cycles were evaluable for the bleeding pattern. The onset of the scheduled bleeding (withdrawal bleeding) was in all cycles on day 11 of the combined phase or beyond. Unlike the duration, the severity of the scheduled bleeding episodes was estrogen-dose dependent. In the entire treatment period of 2 x 84 days, breakthrough bleeding occurred in 3 women, totalling 9 days. Spotting occurred rarely and was equally divided among the treatment groups. CONCLUSIONS: A quarterly sequential hormone replacement therapy regimen for women with anintact uterus gives rise to the development of simple hyperplasia without cytological atypia at the end of the unopposed estrogen phase. This occurs independent of the estrogen dose and can be reverted to inactive or atrophic endometrium by the addition of gestodene during 12 days. The combination offers good cycle control. The safety aspects should be investigated further in long-term studies before this regimen can be advocated for routine use.

Analysis of Variance↗
PubMed1996

Humoral immune response to polymorphic epithelial mucin (MUC-1) in patients with benign and malignant breast tumours.

To investigate the clinical significance of an immune response to the MUC-1 encoded polymorphic epithelial mucin (PEM) breast cancer, circulating immune complexes containing PEM (PEM.CIC) were measured in sera from 96 healthy women, in pretreatment serum samples from 40 patients with benign breast tumours and from 140 patients with breast cancer and in serum samples from 61 breast cancer patients with recurrent or progressive disease. PEM.CIC were measured using a sandwich enzyme-linked immunoassay, and PEM serum levels were measured with CA 15.3 IRMA (Centocor Inc., Malvern, Pennsylvania, U.S.A.). Cut-off levels used for PEM.CIC and CA 15.3 were 120 Optical Density Units (O.D.) x 10(3) and 30 U/ml, respectively. In benign tumours, positivity for PEM.CIC was 37.5% (15/40). 36 of the 140 patients (25.7%) in the breast cancer pretreatment group had elevated PEM.CIC values. In patients with advanced metastatic disease, positivity for PEM.CIC was 18% (11/61). PEM.CIC was elevated in 32% (24/74) of node-negative patients, but only in 20% (12/59) of node-positive patients and absolute values were higher in node-negative patients (Mann-Whitney U test, two-tailed P = 0.0168). There was an inverse correlation between positivity for PEM.CIC and extent of disease: while 3 of the 6 patients with a carcinoma in situ were positive, only 1 of the 15 patients with more than five nodes involved had elevated levels of PEM.CIC. All 7 patients with distant metastases at first diagnosis were PEM.CIC negative. 28 out of 133 patients had a recurrence during the observation period (median 55 months, range 27-84 months). 23 of these 28 patients (82%) were PEM.CIC negative at the moment of first diagnosis. None of the patients with pretreatment elevation of both PEM.CIC and CA 15.3 (n = 13) relapsed. Our preliminary clinical results suggest that a humoral immune response to PEM protects against disease progression, and further support the idea of using synthetic peptides or glycopeptides containing the immunogenic core of the mucin as cancer vaccines.

Adult↗
PubMed1996

Serum tumor marker immunoassays in gynecologic oncology: establishment of reference values.

OBJECTIVE: Our purpose was to establish reference values for six monoclonal antibody-based serum immunoassays applied in patients with carcinoma of the female genital tract. STUDY DESIGN: Sera from 938 healthy women (median age 48.0 years, range 37 to 76 years) were assayed for levels of CA 125, CA 15.3 (two methods), CA M29, CA M26, and mucin-like cancer antigen (MCA). RESULTS: Reference values, defined as those including 95% of healthy controls, were in women with unknown menopausal status as follows: CA 125, 37 U/ml; CA 15.3 (Centocor), 33 U/ml; CA 15.3 (Boehringer Mannheim), 28 U/ml; CA M26, 83 U/ml; CA M29, 13 U/ml; and MCA, 19 U/ml. Postmenopausal values were significantly lower for CA 125 and CA M26 and significantly higher for CA M29 and CA 15.3 (both methods). MCA serum levels were age independent. CONCLUSION: Reference values found were not in accord with those generally applied in gynecologic oncology. In addition, serum levels were influenced significantly by menopausal status (except with MCA).

Adult↗
PubMed1996

Intraperitoneal photodynamic therapy of the rat CC531 adenocarcinoma.

The goal of this study was to investigate the efficacy of photodynamic therapy (PDT) of a single tumour growing intraperitoneally. For this purpose the CC531 colon carcinoma, implanted in an intraperitoneal fat pad of Wag/RijA rats, was treated with intraperitoneal photodynamic therapy (IPPDT) using Photofrin as the photosensitiser. Two illumination techniques have been compared. An invasive illumination technique using Perspex blocks to illuminate 30 cm2 of the lower abdomen gave a significant delay in tumour growth with 25 J cm-2 applied 1 day after Photofrin. A minimally invasive illumination technique using a balloon catheter to illuminate 14 cm2 resulted in an equivalent growth delay with 75 J cm-2. The route of administration of the photosensitiser did not influence regrowth times of the tumour. Mitomycin C (MMC), a bioreductive agent, was used to exploit the known PDT-induced hypoxia. The combination of IPPDT with MMC resulted in an increased tumoricidal effect. In conclusion, IPPDT led to a significant growth delay for a single tumour implanted intraperitoneally and repetition of the PDT treatment was possible using a minimally invasive illumination technique. Repeated treatments resulted in increased tumour response.

Adenocarcinoma↗
PubMed1996

Specificity and affinity of 26 monoclonal antibodies against the CA 125 antigen: first report from the ISOBM TD-1 workshop. International Society for Oncodevelopmental Biology and Medicine.

The specificity of 26 monoclonal antibodies against the CA 125 antigen was investigated in two phases of the ISOBM TD-1 workshop. The binding specificity was studied using CA 125 immunoextracted by specific antibodies immobilized on various solid phases, or on the surface of human cell lines. Immunometric assays using all possible antibody combinations were used to study the topography of antibody binding sites on the antigen. We conclude that the CA 125 antigen carries only two major antigenic domains, which classifies the antibodies as OC125-like (group A) or M11-like (group B). One antibody, OV 197, showed binding specificity related to some of the OC125-like antibodies, but was classified into a separate group C. The OC125-like group of antibodies has four subgroups with different binding specificities. These are A1 = OC 125 and K 95, A2 = K 93, A3 = B43.13, and A4 = ZS 33, B27.1 and CCD 247. Binding of nonlabelled OC 125 or K 95 to CA 125 caused a marked increase in binding of labelled OV 197 to the complex. This conformational change was not observed with any other antibody combinations. Antibody B43.13 could form immunometric assay combinations particularly with antibodies of subgroup A4, indicating that the B43.13 epitope is in the periphery of the binding area of OC125-like antibodies. The M11-like group of antibodies is more homogenous with strong cross-inhibition between most antibodies. Only one antibody, ZR 38, would form an immunoassay combination with other M11-like antibodies and thus represents a distinct subgroup. The main group of M11-like antibodies are M 11, ZR 45, MA602-6, K 91, OV 185, K 101, K 90, K 96, K 97, K 102, CCD 242, 145-9, and 130-22. Antibody OV 197 binds to a domain designated C and is unique, as stated above. Antibody pairs from any two of the three groups may be used in immunometric assays. Three antibodies were not studied by complete cross-inhibition due to low affinity (OV 198 and K 100) or lack of material (MA602-1). OV 198 and K 100 are most likely OC125-like and MA602-1 is M11-like. Antibody affinity was estimated with labelled antigen in solution or with antigen absorbed on microtiter wells. Western blot analysis showed staining both in the stacking gel and corresponding to a molecule of 200 kDa. There was a marked difference between the antibodies in their ability to bind to CA 125 immobilized on a membrane. Strongest binding was observed with the M11-like antibodies, particularly M 11, K 96, K 97, MA602-6, 145-9. Antibodies belonging to the subgroup A4 were the only OC 125-like antibodies which reacted well with CA 125 in Western analysis. Digestion of CA 125 with proteolytic enzymes showed it to be particularly sensitive to trypsin cleavage. However, no low molecular weight fragments with preserved immunoreactivity were found.

Animals↗