W P Collins

King's College London, Londinium, England, United Kingdom

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Publications (217)928.55 Total impact

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    ABSTRACT: Summary Spermatozoa from 269 male partners of infertile couples were assessed using both the mixed erythrocyte-spermatozoa antiglobulin reaction (MAR test) against IgG and the heterologous ovum penetration test. Penetration of zona-free hamster ova occurred with spermatozoa from 39 out of 60 men (65 per cent) with a positive MAR (IgG) test result, and statistical analysis demonstrated that the penetration of zona-free hamster ova is not related to the result of the MAR (IgG) test.
    07/2009; 5(1):42-44.
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    ABSTRACT: Summary— Investigation of 311 azoospermic males has shown that the combination of estimation of testicular size and plasma FSH allows the spermatogenic funciton of th testes to be accurately assessed by non-invasive method.Patients with small testes and grossly elevated levels of plasma FSH have absent, or grossly impaired spermatogenesis, and do not require surgical exploraion. They should be advised with regard to adoption or artificial inseminaition.Patients with large testes (5 cm) or an FSH level which is not grossly elevated require operation and should undergo a surgical exploration and the possible corretion of an obstructive lesion. A testicular biopsy is essential if no obstructive lesion is found as the histology of these patients may show a spermatolgenic arrest.
    BJU International 11/2008; 50(7):591 - 594. · 3.05 Impact Factor
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    ABSTRACT: This study describes the experience of screening and surgery in a sample of women who received false positive results during screening for familial ovarian cancer. It was hypothesised that these women might feel bitter and hostile at having been exposed to so much anxiety and suffering for the removal of a cyst. The results from both prospective questionnaire measures and retrospective interviews indicated that women were neither severely distressed nor angry about their experiences. The sensitive management of the screening process by clinic staff and a remarkable faith in the benefits of early intervention held by the women involved, appeared to have contributed to this positive outcome. Women's acceptance of major surgery seemed to be based on the premise that body parts which were not crucial to survival, and which were at risk of malignancy, were best removed under the circumstances. They seemed to derive considerable comfort from the belief that surgery rendered them invulnerable to the disease that had, in most cases, caused their mother a painful death. Nevertheless, many women described considerable stress at various stages in the procedure. An improvement in the quality and timing of information may further reduce anxiety.
    Psycho-Oncology 03/2007; 1(4):217 - 233. · 3.51 Impact Factor
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    ABSTRACT: To collect data for the development of a more universally useful logistic regression model to distinguish between a malignant and benign adnexal tumor before surgery. Patients had at least one persistent mass. More than 50 clinical and sonographic end points were defined and recorded for analysis. The outcome measure was the histologic classification of excised tissues as malignant or benign. Data from 1,066 patients recruited from nine European centers were included in the analysis; 800 patients (75%) had benign tumors and 266 (25%) had malignant tumors. The most useful independent prognostic variables for the logistic regression model were as follows: (1) personal history of ovarian cancer, (2) hormonal therapy, (3) age, (4) maximum diameter of lesion, (5) pain, (6) ascites, (7) blood flow within a solid papillary projection, (8) presence of an entirely solid tumor, (9) maximal diameter of solid component, (10) irregular internal cyst walls, (11) acoustic shadows, and (12) a color score of intratumoral blood flow. The model containing all 12 variables (M1) gave an area under the receiver operating characteristic curve of 0.95 for the development data set (n = 754 patients). The corresponding value for the test data set (n = 312 patients) was 0.94; and a probability cutoff value of .10 gave a sensitivity of 93% and a specificity of 76%. Because the model was constructed from multicenter data, it is more likely to be generally applicable. The effectiveness of the model will be tested prospectively at different centers.
    Journal of Clinical Oncology 01/2006; 23(34):8794-801. · 18.04 Impact Factor
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    ABSTRACT: Objective To investigate the endocrine changes associated with spontaneous miscarriage after fetal heart activity has been demonstrated.Design Prospective study during the first trimester of pregnancy comparing the circulating levels of human chorionic gonadotrophin (hCG), Schwangerschaft protein 1 (SP-1), pregnancy-associated plasma protein A (PAPP-A), oestradiol (E2), and progesterone (P), and fetal growth (crown-rump length [CRL] and gestational sac volume [GSV]) in women who miscarried after the identification of fetal heart activity with those of normal singleton and twin pregnancies achieved following in vitro fertilisation (IVF) and embryo transfer (ET).Setting The Assisted Conception Unit of King's College Hospital, London.Subjects Nine women who miscarried after demonstration of fetal heart activity, 52 normal singleton and 22 normal twin pregnancies.Interventions Weekly blood tests and ultrasound assessments of CRL and GSV.Results Four fetuses (all singleton) died between 9 and 12 weeks gestation (Group 1), and seven (three singleton and two twin) died between 16 and 20 weeks gestation (Group 2). In Group 1, both fetal growth and placental function, as assessed by serial measurements of CRL and GSV, and of serum levels of PAPP-A, SP-1 and hCG respectively, were reduced before fetal death. In Group 2, while fetal growth was maintained in all but one case, placental function was reduced in 4 of 5 women.Conclusion These findings suggest that there may be a relationship between trophoblast dysfunction and some forms of miscarriage. Furthermore, the pattern of the reduction in the circulating levels of the placental proteins in later miscarriages suggests that the function of specific cell types may be impaired.
    BJOG An International Journal of Obstetrics & Gynaecology 08/2005; 100(4):353 - 359. · 3.76 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 08/2003; 22(S1):101 - 102. · 3.56 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 08/2003; 22(S1):62 - 63. · 3.56 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 08/2003; 22(S1):3 - 4. · 3.56 Impact Factor
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    ABSTRACT: To assess the use of transvaginal sonography as a screening test for familial ovarian cancer and, secondarily, to determine the value of a family history of malignant disease and the potential role of serum CA 125 levels in the screening procedure. Two thousand five hundred self-referred women were studied at the Ovarian Screening Clinic at King's College Hospital, London. These symptom-free women with at least one close relative who had developed ovarian cancer were studied prospectively. Each woman was scanned for the presence of a persistent ovarian lesion and a sample of peripheral blood was taken for the retrospective analysis of serum CA 125. Women with a positive screen result were referred for surgical investigations; those with a negative result but considered to be at high risk were rescreened. The main outcome measures were findings at surgery, the histological classification of ovarian lesions, and cancer reported at follow-up. The women were aged 17 to 78 (mean, 48) years; 65% were premenopausal, 26% were postmenopausal and 9% had undergone hysterectomy. Seven hundred and thirty-eight women (29.5%) had a family history of multiple site cancers and 279 (11.2%) reported cancer specific to the ovary. There were 4231 screenings (2500 first screens, 998 second screens and 733 third or higher order screens). One hundred and four screens gave a positive result (2.5%); 11 cancers were detected (seven (64%) at stage I, four of which were of borderline malignancy). One additional cancer was reported within 12 months of the last scan and classified as a false-negative screen result. Eight cancers (including two peritoneal) were reported at follow-up (> 1-9 years after the last scan). All these women presented at an advanced stage (stage III). Fifteen of 20 cancers occurred in premenopausal women. The overall sensitivity of ultrasound screening was 92% (95% confidence interval, 76-100); the specificity was 97.8%. The prior odds of any woman having a screen-detectable ovarian malignancy during the study period were 1 : 207. The posterior odds subsequent to a positive screen result were 1 : 8.5 (1 : 12.7 at Screen 1; 1 : 3.7 at Screen 2; 1 : 3.0 at subsequent screens); the value was 1 : 11.4 for women with one family relative with ovarian cancer and 1 : 5.0 for women with the site-specific ovarian cancer syndrome. The prior use of a decision level for serum CA 125 >or= 20 U/mL would have reduced the number of women undergoing sonography by 78%; seven of the 12 cancers (58%) would have been detected (63% of all stage I disease, 75% of invasive stage I disease). An alternative cut-off value of 35 U/mL would have resulted in a detection rate of 33%. Transvaginal sonography can effectively detect intraovarian cancer and tumors of borderline malignancy in women with a family history of the disease. Screening efficacy is related to the type of family history. The level of serum CA 125 can be used to select women for sonography, but the detection rate for early cancers would be reduced.
    Ultrasound in Obstetrics and Gynecology 04/2003; 21(4):378-85. · 3.56 Impact Factor
  • Ultrasound in Medicine and Biology - ULTRASOUND MED BIOL. 01/2003; 29(5).
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    ABSTRACT: To evaluate the uptake and outcome of expectant management of spontaneous first trimester miscarriage in an early pregnancy assessment unit. 1096 consecutive patients with a diagnosis of spontaneous first trimester miscarriage. Each miscarriage was classified as complete, incomplete, missed, or anembryonic on the basis of ultrasonography. Women who needed treatment were given the choice of expectant management or surgical evacuation of retained products of conception under general anaesthesia. Women undergoing expectant management were checked a few days after transvaginal bleeding had stopped, or they were monitored at weekly intervals for four weeks. A complete miscarriage (absence of transvaginal bleeding and endometrial thickness <15 mm), the number of women completing their miscarriage within each week of management, and complications (excessive pain or transvaginal bleeding necessitating hospital admission or clinical evidence of infection). Two patients with molar pregnancies were excluded, and 37% of the remainder (408/1094) were classified as having had a complete miscarriage. 70% (478/686) of women with retained products of conception chose expectant management; of these, 27 (6%) were lost to follow up. A successful outcome without surgical intervention was seen in 81% of cases (367/451). The rate of spontaneous completion was 91% (201/221) for those cases classified as incomplete miscarriage, 76% (105/138) for missed miscarriage, and 66% (61/92) for anembryonic pregnancy. 70% of women completed their miscarriage within 14 days of classification (84% for incomplete miscarriage and 52% for missed miscarriage and anembryonic pregnancy). Most women with retained products of conception chose expectant management. Ultrasonography can be used to advise patients on the likelihood that their miscarriage will complete spontaneously within a given time.
    BMJ (online) 04/2002; 324(7342):873-5. · 17.22 Impact Factor
  • Gynecologic Oncology 11/2001; 83(1):166-8. · 3.93 Impact Factor
  • Gynecologic Oncology. 10/2001; 83(1):166–167.
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    Ultrasound in Obstetrics and Gynecology 11/2000; 16(5):500-5. · 3.56 Impact Factor
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    ABSTRACT: Whether some benign ovarian cysts can develop into cancerous cysts is not known. If a large proportion of ovarian cancers arose in this way, it might be possible to remove the benign cysts in a screening programme before they became malignant. We used follow-up data from a cohort of 5479 self-referred women without symptoms, who participated in a ultrasonographic-screening trial for early ovarian cancer between June, 1981, and August, 1987. We assessed whether the removal of persistent ovarian cysts from these women was associated with a reduction in the expected number of deaths from ovarian cancer in the cohort as a whole. The expected number of deaths from all causes, all cancers, and ovarian, breast, and colorectal cancers were calculated for the study cohort by the standard life-table method. The actual number of deaths and each cause were obtained and the proportional mortality ratio was calculated for each cause of death. 5135 (95%) of the participants in the original trial were traced. During the screening, five of these women were found to have stage I epithelial ovarian cancer and 88 had benign epithelial ovarian tumours. The number of reported deaths from all causes (387 [50% of expected]), all cancers (221 [71%]), and ovarian cancer (22 [90%]) was lower than expected because of the "healthy-volunteer effect". Proportional mortality ratios were 100% (by definition) for all cancers, 141% for breast cancer, 128% for ovarian cancer (95% CI 87.7-187.6, p=0.19), 84% for colorectal cancer, and 48% for lung cancer. The removal of persistent ovarian cysts was not associated with a decrease in the proportion of expected deaths from ovarian cancer relative to other cancers during follow-up. For population-based screening of healthy women without a family history of ovarian cancer, a screening test is required that is specific and sensitive to early malignant disease, and inexpensive.
    The Lancet 04/2000; 355(9209):1060-3. · 39.21 Impact Factor
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    ABSTRACT: The aim of this study was to assess the complementary use of ultrasonographic end points with the level of circulating CA 125 antigen by multivariate logistic regression analysis algorithms to distinguish malignant from benign adnexal masses before operation. One hundred ninety-one patients aged 18 to 93 years with overt adnexal masses were examined by transvaginal ultrasonography with color Doppler imaging and 31 variables were recorded. The end points were the histologic classification of the tumor and the areas under the receiver-operator characteristic curves of alternative algorithms. One hundred forty patients had benign tumors and 51 (26.7%) had malignant tumors: 31 primary invasive tumors (37% International Federation of Gynecology and Obstetrics stage I), 5 tumors of borderline malignancy (100% International Federation of Gynecology and Obstetrics stage I), and 15 tumors were metastatic and invasive. The most useful variables for the logistic regression analysis were the menopausal status, the serum CA 125 level, the presence of >/=1 papillary growth (>3 mm in length), and a color score indicative of tumor vascularity and blood flow. The optimized procedure had a sensitivity of 95.9% and a specificity of 87.1%. The area under the receiver-operator characteristic curve was significantly higher (P <.01) than the corresponding values from the independent use of serum CA 125 levels or indexes of tumor form or vascularity. Regression analysis of a few complementary variables can be used to accurately discriminate between malignant and benign adnexal masses before operation.
    American Journal of Obstetrics and Gynecology 07/1999; 181(1):57-65. · 3.88 Impact Factor
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    ABSTRACT: The aim of this study was to generate and evaluate artificial neural network (ANN) models from simple clinical and ultrasound-derived criteria to predict whether or not an adnexal mass will have histological evidence of malignancy. The data were collected prospectively from 173 consecutive patients who were scheduled to undergo surgical investigations at the University Hospitals, Leuven, between August 1994 and August 1996. The outcome measure was the histological classification of excised tissues as malignant (including borderline) or benign. Age, menopausal status and serum CA 125 levels and sonographic features of the adnexal mass were encoded as variables. The ANNs were trained on a randomly selected set of 116 patient records and tested on the remainder (n = 57). The performance of each model was evaluated using receiver operating characteristic (ROC) curves and compared with corresponding data from an established risk of malignancy index (RMI) and a logistic regression model. There were 124 benign masses, five of borderline malignancy and 44 invasive cancers (of which 29% were metastatic); 37% of patients with a malignant or borderline tumor had stage I disease. The best ANN gave an area under the ROC curve of 0.979 for the whole dataset, a sensitivity of 95.9% and specificity of 93.5%. The corresponding values for the RMI were 0.882, 67.3% and 91.1%, and for the logistic regression model 0.956, 95.9% and 85.5%, respectively. An ANN can be trained to provide clinically accurate information, on whether or not an adnexal mass is malignant, from the patient's menopausal status, serum CA 125 levels, and some simple ultrasonographic criteria.
    Ultrasound in Obstetrics and Gynecology 02/1999; 13(1):17-25. · 3.56 Impact Factor
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    ABSTRACT: The aim of the study was to evaluate the subjective assessment of ultrasonographic images for discriminating between malignant and benign adnexal masses. The study was prospective. Initially, one ultrasonographer preoperatively assessed 300 consecutive patients with adnexal masses. Subsequently, the recorded transparent photographic prints were independently assessed by five investigators, with different qualifications and level of experience, who were also given a brief clinical history of the patients (i.e. the age, menstrual status, family history of ovarian cancer, previous pelvic surgery and the presenting symptoms). The diagnostic performance of the observers was compared with the histopathology classification of malignant or benign tumors. The end-points were accuracy, interobserver agreement and the possible effect of experience. The first ultrasonographer and the most experienced investigator both obtained an accuracy of 92%. There was very good agreement between these two investigators in the classification of the adnexal masses (Cohen's kappa 0.85). The less experienced observers obtained a significantly lower accuracy, which varied between 82% and 87%. Their interobserver agreement was moderate to good (Cohen's kappa 0.52 to 0.76). Experienced ultrasonographers using some clinical information and their subjective assessment of ultrasonographic images can differentiate malignant from benign masses in most cases. The accuracy and the level of interobserver agreement are both correlated with experience. About 10% of masses were extremely difficult to classify (only < 50% of assessors were correct).
    Ultrasound in Obstetrics and Gynecology 01/1999; 13(1):11-6. · 3.56 Impact Factor
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    ABSTRACT: Objective To generate a neural network algorithm which computes a probability of malignancy score for pre-operative discrimination between malignant and benign adnexal tumours.Design A retrospective analysis of previously collected data. Information from 75% of the study group was used to train an artificial neural network and the remainder was used for validation.Setting The Gynaecological Ultrasound Research Unit at King's College Hospital, London.Population Sixty-seven women with known adnexal mass who had been examined using transvaginal B-mode ultrasonography and colour Doppler imaging with pulse spectral analysis immediately before surgery. The excised masses were classified histologically as benign (n= 52) or malignant (n= 19, of which three were borderline.Methods The variables that were put into the artificial neural network were: age, menopausal status, maximum tumour diameter, tumour volume, locularity, the presence of papillary projections, the presence of random echogenecity, the presence of analysable blood flow velocity waveforms, the peak systolic velocity, time-averaged maximum velocity, the pulsatility index, and resistance index. Histological classification, categorised as benign or malignant, was the output result.Results A variant of the back propagation method was selected to train the network. The overall architecture of the network with the best performance contained an input layer with four variables (age, time-averaged maximum velocity, papillary projection score and maximum tumour diameter), a hidden layer with three units and an output layer with one. The sensitivity and specificity at the optimum diagnostic decision value for the artificial neural network output (0.45) were 100% (95% CI 78.2%–100%) and 98.1% (95% CI 89.5%–100%), respectively. These values were significantly better than those obtained from the independent use of the resistance index, pulsatility index, time-averaged maximum velocity or peak systolic velocity at their optimum decision values (P < 0.01).Conclusion Artificial neural networks may be used on clinical and ultrasound derived end-points to accurately predict ovarian malignancy. There is a need for a prospective evaluation of this technique using a larger number of patients.
    BJOG An International Journal of Obstetrics & Gynaecology 12/1998; 106(1):21 - 30. · 3.76 Impact Factor
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    ABSTRACT: A high proportion of asymptomatic tamoxifen-treated postmenopausal breast cancer patients have endometrial pathology (polyps, hyperplasia and cancer). Thick endometrium, as measured with ultrasound, is associated with pathology. Transvaginal sonography (with saline infusion sonography (SIS), if indicated) may be more effective and acceptable than office hysteroscopy for detecting these endometrial abnormalities. However, the value of endometrial surveillance in asymptomatic patients has not been proven, because this would require a prospective randomised trial including several thousands of tamoxifen-treated breast cancer patients, using mortality from endometrial cancer as an end-point.
    European Journal of Cancer 08/1998; 34. · 5.06 Impact Factor

Publication Stats

4k Citations
928.55 Total Impact Points

Institutions

  • 1977–2009
    • King's College London
      Londinium, England, United Kingdom
  • 1987–2007
    • The Peninsula College of Medicine and Dentistry
      • School of Medicine
      Plymouth, England, United Kingdom
  • 1998–2000
    • KU Leuven
      • Department of Reproduction, Development and Regeneration
      Leuven, VLG, Belgium
    • University of Gothenburg
      • Department of Obstetrics and Gynecology
      Göteborg, Vaestra Goetaland, Sweden
    • University Hospital Southampton NHS Foundation Trust
      Southampton, England, United Kingdom
  • 1996–1998
    • Sahlgrenska University Hospital
      • Department of Cardiology
      Goeteborg, Västra Götaland, Sweden
    • London School of Hygiene and Tropical Medicine
      Londinium, England, United Kingdom
  • 1972–1996
    • University of London
      Londinium, England, United Kingdom
  • 1994
    • University College London Hospitals NHS Foundation Trust
      • Department of Obstetrics and Gynaecology
      London, ENG, United Kingdom
  • 1993–1994
    • Chelsea and Westminster Hospital NHS Foundation Trust
      Londinium, England, United Kingdom
  • 1987–1989
    • University College Hospital Ibadan
      Ibadan, Oyo, Nigeria
  • 1981–1982
    • Weizmann Institute of Science
      Israel
  • 1976
    • St. Peter's Hospital
      Helena, Montana, United States