Identification of a novel prostate cancer susceptibility variant in the KLK3 gene transcript

Genome-wide association studies (GWAS) have identified more than 30 prostate cancer (PrCa) susceptibility loci. One of these (rs2735839) is located close to a plausible candidate susceptibility gene, KLK3, which encodes prostate-specific antigen (PSA). PSA is widely used as a biomarker for PrCa detection and disease monitoring. To refine the association between PrCa and variants in this region, we used genotyping data from a two-stage GWAS using samples from the UK and Australia, and the Cancer Genetic Markers of Susceptibility (CGEMS) study. Genotypes were imputed for 197 and 312 single nucleotide polymorphisms (SNPs) from HapMap2 and the 1000 Genome Project, respectively. The most significant association with PrCa was with a previously unidentified SNP, rs17632542 (combined P = 3.9 × 10⁻²²). This association was confirmed by direct genotyping in three stages of the UK/Australian GWAS, involving 10,405 cases and 10,681 controls (combined P = 1.9 × 10⁻³⁴). rs17632542 is also shown to be associated with PSA levels and it is a non-synonymous coding SNP (Ile179Thr) in KLK3. Using molecular dynamic simulation, we showed evidence that this variant has the potential to introduce alterations in the protein or affect RNA splicing. We propose that rs17632542 may directly influence PrCa risk.

Hand pattern indicates prostate cancer risk

BACKGROUND

The ratio of digit lengths is fixed in utero, and may be a proxy indicator for prenatal testosterone levels.

METHODS

We analysed the right-hand pattern and prostate cancer risk in 1524 prostate cancer cases and 3044 population-based controls.

RESULTS

Compared with index finger shorter than ring finger (low 2D : 4D), men with index finger longer than ring finger (high 2D : 4D) showed a negative association, suggesting a protective effect with a 33% risk reduction (odds ratio (OR) 0.67, 95% confidence interval (CI) 0.57-0.80). Risk reduction was even greater (87%) in age group <60 (OR 0.13, 95% CI 0.09-0.21).

CONCLUSION

Pattern of finger lengths may be a simple marker of prostate cancer risk, with length of 2D greater than 4D suggestive of lower risk.

SNP-LOH Analysis of Lobular Carcinoma In Situ and Associated Invasive Lobular Cancer

Background: Lobular carcinoma in situ (LCIS) is a risk factor for the development of subsequent invasive breast carcinoma in either breast. Approximately 50-70% of these subsequent cancers are invasive lobular carcinoma (ILC). Recent molecular evidence suggests that LCIS may be a precursor of ILC. However, not all LCIS progresses to invasive disease and at present there are no biomarkers that predict which cases are going to develop invasive disease. SNP-LOH analysis may be a useful method to analyse genome wide loss of heterozygosity (LOH) and copy number variation in LCIS and associated invasive disease in order to identify such biomarkers. The study of LCIS poses specific technical challenges as available samples are almost exclusively formalin fixed paraffin embedded (FFPE) tissue and LCIS tends to occur in small scattered foci which require micro-dissection.Aims: To assess the feasibility of performing SNP-LOH on micro-dissected FFPE tissue To compare patterns of LOH in pure LCIS and LCIS associated with ILCTo examine the genetic relationship between LCIS and associated ILCMethods: Tumour blocks were collected as part of the GLACIER Study (a study to investigate the Genetics of LobulAr Carcinoma In situ in EuRope). Tissue was micro-dissected from FFPE specimens. DNA was extracted with the DNEasy kit (Qiagen) if it was possible to micro-dissect by hand under a light microscope. For cases extracted using the laser capture microscope (LCM) the Picopure Kit (MDS Analytical Tech)) was used to extract DNA. SNP-LOH was performed using the GoldenGate Assay(Illumina) on 28 samples (20 LCIS, 8 ILC). A minimum of 250ng of DNA was required. For samples with low DNA yields, DNA was amplified using the Genomeplex Amplification Kit(Sigma).Results: Results were obtained on 24 samples that were micro-dissected under the light microscope and extracted using the DNEasy kit(Qiagen). Amplification of DNA was also possible from these samples and the SNP-LOH results for amplified DNA correlated with those for unamplified DNA(1 case).SNP-LOH was performed on 13 cases of classical LCIS: 6 pure LCIS, 7 with associated ILC. LOH events were more common in LCIS associated with invasive disease (range 2-5, median 3) than pure LCIS (range 0-5, median 2). The commonest change in both groups was 16q LOH (6/6 LCIS with invasive disease, 4/7 pure LCIS, p=0.12, Fishers Exact Test). 1q LOH was also present in all samples associated with invasive disease, but only identified in 3/7 samples of pure LCIS (p=0.049, Fishers Exact Test). There were also other regions of LOH that were more common in LCIS associated with ILC, but did not reach significance.Comparing LOH patterns in LCIS and associated ILC revealed that in 3/6 cases of ILC genetic changes were identical to those in the LCIS. In 2/6 cases the ILC had the same genetic changes but had also acquired new genetic changes. Interestingly in 1 case the LCIS had more genetic changes than the ILC.Conclusions: This pilot study has shown that it is possible to perform SNP-LOH on small amounts of micro-dissected FFPE tissue. The results confirm the findings of others that LCIS is a likely precursor lesion of ILC and suggest that even with this limited number of samples pure LCIS and LCIS associated with ILC may have different genetic profiles.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5169.

Use of serum progesterone measurements to reduce need for follow-up in women with pregnancies of unknown location

OBJECTIVE

To assess the efficacy of a progesterone-based algorithm for the management of women with pregnancies of unknown location (PULs) and explore the feasibility of developing a single-visit strategy in those with a low risk of requiring medical intervention.

METHODS

All clinically stable women in whom pregnancy could not be identified on ultrasound scan were managed by a pre-defined protocol based on measurement of serum progesterone and beta-human chorionic gonadotropin (beta-hCG). Intervention in the form of surgery or medical treatment with methotrexate was offered to all women with persistent or worsening symptoms and non-declining serum beta-hCG. Decision-tree analysis was used to develop a protocol for the management of women with resolving pregnancies who are at low risk of requiring medical intervention.

RESULTS

1110 women were included in the data analysis: normal intrauterine pregnancy was diagnosed in 248 (22.3%; 95% CI, 19.9-24.8) women. 761 (68.6%; 95% CI, 65.8-71.3) abnormal pregnancies resolved spontaneously on expectant management, while the remaining 101 (9.1%; 95% CI, 7.4-10.8) women with abnormal pregnancies required some form of medical intervention. Intervention rates in patients presenting with initial serum progesterone levels of <or= 20 nmol/L and <or= 10 nmol/L, were 3.9% (95% CI, 2.4-5.4) and 2.1% (95% CI, 0.9-3.3), respectively. In women presenting with progesterone <or= 10 nmol/L and beta-hCG < 450 IU/L, the intervention rate was 1.3% (95% CI, 0.2-2.5).

CONCLUSION

Women with PULs with progesterone <or= 10 nmol/L at presentation are at low risk of requiring medical intervention and may not benefit from attending routine follow-up visits.

Local recurrence rates in the conserved breast after MRI targeted radiotherapy

Abstract #5143

Background: To optimise the effects of whole breast irradiation after breast conservation surgery, precise identification and delineation of clinical target volumes is essential. If the site of the “post-operative cavity” (POCx) is inaccurately located, any target miss of residual cancer cells may lead to underdosing and thus impact on local recurrence rates and survival. Studies with surgical clips have shown rates of geographical miss of the POCx to be worryingly high for radiotherapy boost doses (up to 87%). Of even more concern is that the whole breast tangential fields frequently miss the tumour bed even though the fields appear adequate based on external landmarks (in approximately a quarter of cases). MRI has subtle breast tissue characterisation that may demonstrate post-operative detail more clearly than CT and more accurately than surgical clips.&#x2028; Methods and Materials: Simple opposed tangential fields were defined by surface anatomy in the conventional manner in 221 consecutive patients. Following MR imaging, fields were modified by a single radiation oncologist (EW) to encompass the POCx with a 10mm margin. Patients were treated to a dose of 45Gy in 20 fractions or 50Gy in 25 fractions, with or without an electron boost to the tumour bed (usually 12.5Gy in 5 fractions). Genetic analysis, using genome wide single nucleotide polymorphism (SNP) arrays and loss of heterozygosity (LOH), was performed on all local relapses to distinguish true recurrences (TRs) from new primaries (NPs)&#x2028; Results: This cohort was at relatively high risk, with only 9.8% classified as low risk by St Gallen criteria. 43.4% were grade 3 and 19.9% had surgical margins &lt;1mm. 62.4% of patients received boosts to the tumour bed. After a median follow-up of 5 years there were 3 local recurrences. This is an actuarial 5-year local relapse rate of 1.3%. Genetic analysis showed that 2 local relapses had identical genetic profiles to the initial primaries; they were TRs. The other was genetically distinct; it was an NP.&#x2028; Conclusions: In this cohort of relatively high risk patients, the TR rate was 0.9% at 5 years. These figures compare favourably with the EORTC boost trial and the START results, although both of these studies had different inclusion criteria, particularly with regard to surgical margins. Theoretically, TRs should be the type of relapse most likely to be avoided by accurate coverage of the post-operative complex. Radiotherapy planned with guidance from MR images may cover the clinical target volume more accurately than treatment guided by anatomical landmarks alone.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5143.

Deficient lower-segment Cesarean section scars: prevalence and risk factors

OBJECTIVE

To examine the sonographic features of transverse lower-segment uterine Cesarean section scars in non-pregnant, premenopausal women and to identify factors associated with scar deficiency.

METHODS

Non-pregnant, premenopausal women with histories of previous transverse lower-segment Cesarean sections, who were referred for an ultrasound scan for a variety of gynecological indications, were included in this study. An attempt was made to identify the uterine scars on transvaginal ultrasound scan and to describe their locations and morphological features. Various demographic, clinical and ultrasound data were examined in order to identify factors associated with deficient scars. Deficient scars were defined as detectable myometrial thinning at the site of the Cesarean section scar.

RESULTS

Lower-segment uterine scars were detected in 321/324 (99.1%; 95% CI, 98.0-100) women with a history of previous Cesarean section. Sixty-three (19.4%; 95% CI, 15.1-23.8) women had evidence of deficient Cesarean scars. Using multivariate analysis, a history of multiple Cesarean sections, uterine retroflexion and the inability to visualize all Cesarean scars in women with previous multiple Cesarean sections were all shown to be significantly associated with deficient scars.

CONCLUSION

Deficient uterine scars are a frequent finding in women with a history of previous Cesarean section. The risk of scar deficiency is increased in women with a retroflexed uterus and in those who have undergone multiple Cesarean sections.

Fertility outcomes following expectant management of tubal ectopic pregnancy

OBJECTIVES

To evaluate fertility outcome after the expectant management of tubal ectopic pregnancy.

METHODS

Our dedicated early pregnancy database was searched for all women diagnosed with a tubal ectopic pregnancy between January 1999 and June 2003 who were either managed expectantly or underwent a salpingectomy. They were contacted to enquire about their ability to conceive following the ectopic pregnancy and about the outcomes of any subsequent pregnancies.

RESULTS

Four hundred and forty-four women had a diagnosis of tubal ectopic pregnancy, and 173 (39%) were successfully contacted. A total of 146/173 (84.4%; 95% CI, 79-89.8%) tried for another pregnancy: 49/59 (83.1%; 95% CI, 73.4-92.6%) in the expectant management and 97/114 (85.1%; 95% CI, 78.4-91.6%) in the salpingectomy group (P > 0.05). Spontaneous intrauterine pregnancy occurred in 41/49 (83.7%; 95% CI, 73.3-94.2%) women managed expectantly and in 62/97 (63.9%; 95% CI, 54.4-73.5%) women managed surgically (odds ratio 2.89; 95% CI, 1.22-6.86%). The risk of recurrent ectopic pregnancy was not significantly different between the two management groups.

CONCLUSIONS

Fertility outcomes following the expectant management of tubal ectopic pregnancy are comparable to those following salpingectomy.

Value of preoperative ultrasound examination in the selection of women with adnexal masses for laparoscopic surgery

OBJECTIVES

To assess the value of preoperative ultrasound examination in predicting the feasibility of intermediate-level laparoscopic surgery for benign adnexal masses.

METHODS

Symptomatic women with a clinical or ultrasound diagnosis of adnexal mass were offered a detailed transvaginal ultrasound scan in order to assess the feasibility of laparoscopic cystectomy/oophorectomy. In all cases an attempt was made to establish a likely histological diagnosis using the pattern recognition method. The selection criteria for laparoscopic surgery were: no ultrasound features suggestive of ovarian cancer, predominantly cystic lesion with no solid foci > 5 cm in mean diameter, no evidence of severe pelvic endometriosis or severe pelvic adhesions and dermoid cyst < 10 cm in mean diameter. Laparoscopic surgery was classified as successful if the mass was removed completely without resorting to a laparotomy.

RESULTS

One hundred and forty-three women were diagnosed with a total of 162 adnexal cysts. The final dataset consisted of 137 women (with 153 lesions), 113 (82.5%) of whom were selected for laparoscopy and 24 (17.5%) for laparotomy. On histological examination 152 (99.3%) cysts were benign and the remaining one (0.7%) was borderline. The operation was successfully completed laparoscopically in 107/113 (94.7%) cases. The preoperative ultrasound assessment predicted the successful outcome of laparoscopic surgery with a sensitivity of 98% (95% CI, 94-99%), specificity of 79% (95% CI, 60-90%), positive predictive value of 95% (95% CI, 89-98%), positive likelihood ratio of 4.58 (95% CI, 2.25-9.32) and negative likelihood ratio of 0.02 (95% CI, 0.01-0.09).

CONCLUSIONS

A detailed preoperative transvaginal ultrasound examination is a helpful tool for assessing the feasibility of intermediate-level laparoscopic surgery in women with benign adnexal lesions.

Ultrasound diagnosis of ectopic pregnancy in the non-communicating horn of a unicornuate uterus (cornual pregnancy)

OBJECTIVE

To prospectively evaluate ultrasound criteria for the diagnosis of pregnancy in the rudimentary horn of a unicornuate uterus (cornual pregnancy).

METHODS

This was a prospective observational study over a period of 90 months in a tertiary referral center in a London teaching hospital. A diagnosis of cornual pregnancy was made when all the following ultrasound criteria were met: (1) a single interstitial portion of Fallopian tube in the main uterine body; (2) a gestational sac, mobile and separate from the uterus, surrounded by myometrium; and (3) a vascular pedicle joining the gestational sac to the unicornuate uterus. In cases where the ultrasound criteria were met the pregnancy was followed up and the final outcome was recorded, including operative and histological findings.

RESULTS

Over the study period eight cases of cornual pregnancy were diagnosed. Six women had a single case of cornual pregnancy. One woman was managed expectantly in her first cornual pregnancy and subsequently suffered a recurrence. Surgical management varied depending on viability of the pregnancy and gestational age at presentation. In all the women who underwent surgery the diagnosis was eventually confirmed at operation and on histological examination. During the study period there were no false positive or false negative results in our unit using the above criteria.

CONCLUSION

The proposed ultrasound criteria appear accurate and may be applied in clinical practice to facilitate preoperative diagnosis of cornual ectopic pregnancy.

Efficacy of Shirodkar cervical suture in securing hemostasis following surgical evacuation of Cesarean scar ectopic pregnancy

OBJECTIVES

To assess the efficacy of a Shirodkar cervical suture in arresting hemorrhage following surgical removal of a Cesarean scar ectopic pregnancy.

METHODS

The study included women with an ultrasound diagnosis of Cesarean scar ectopic pregnancy who were scheduled for surgical evacuation. After administration of general anesthetic, a Shirodkar cervical suture was inserted using the standard surgical technique. The suture was left untied and the Cesarean scar pregnancy was evacuated under ultrasound guidance using suction curettage. Once the pregnancy had been successfully removed, the suture was tied and 500 microg ergometrine was administered intravenously to ensure uterine contraction. The patients were prescribed prophylactic antibiotics and the suture was removed 7 days later in the outpatient setting, under local anesthetic.

RESULTS

Over a 4-year period a total of 33 Cesarean scar pregnancies were diagnosed, and 28 (85%) had surgical evacuation. A cervical suture was necessary to achieve hemostasis in 22/28 (79%; 95% CI, 64-94) cases. In the remaining 6/28 (21%; 95% CI, 6-36) cases, the bleeding was minimal and the suture was not tied. The median estimated intraoperative blood loss was 50 (range, 50-1500) mL. Six of 28 (21%; 95% CI, 6-36) women suffered blood loss > or = 300 mL and two (7%; 95% CI, 0-17) required blood transfusion. One woman (5%; 95% CI, 0-14) required repeat surgery because of retained products of conception. There were no other significant complications and the uterus was preserved successfully in all cases.

CONCLUSIONS

Insertion of a Shirodkar cervical suture during the evacuation of a Cesarean scar pregnancy is an effective method for securing hemostasis; it minimizes the need for blood transfusion and ensures preservation of fertility.

Reproductive outcomes of women with a previous history of Caesarean scar ectopic pregnancies

BACKGROUND

Caesarean scar ectopic pregnancy is associated with a number of significant complications. In this study, we report on subsequent reproductive outcomes in a group of women following successful treatment of their scar pregnancies.

METHODS

The study included those women who received treatment for their Caesarean scar pregnancies between April 1999 and October 2005. Their ability to conceive, the time it took to become pregnant and outcomes of subsequent pregnancies were all recorded.

RESULTS

40 women with Caesarean scar pregnancies were managed in our unit. The uterus was conserved in 38/40 cases. Follow-up data were available in 29/38 (76%) of women. Twenty-four out of 29 (83%) attempted to become pregnant. Twenty-one out of 24 [88%, 95% confidence interval (CI): 75-100] women conceived spontaneously. Twenty out of 21 (95%, 95% CI: 86-100) pregnancies were intrauterine and one woman (5%, 95% CI: 0-14) had a recurrent scar ectopic. Thirteen out of 20 (65%, 95% CI: 44-86) intrauterine pregnancies appeared normal. Nine out of 13 (69%) were delivered by Caesarean section. Seven out of 20 (35%, 95% CI: 14-56) intrauterine pregnancies ended in spontaneous abortions.

CONCLUSIONS

Our study shows that reproductive outcomes following treatment of caesarean scar ectopic pregnancies are favourable. The risk of complications including recurrent scar implantation appears to be low.

The value of measuring endometrial thickness and volume on transvaginal ultrasound scan for the diagnosis of incomplete miscarriage

OBJECTIVE

To identify ultrasound measurements that are the best predictors of the presence of retained products of conception (RPOC) within the uterine cavity in women with clinical diagnosis of incomplete miscarriage.

METHODS

This was a prospective observational study, set in a dedicated early pregnancy assessment unit in a London teaching hospital. Endometrial thickness and the volume of suspected retained products of conception were measured by transvaginal ultrasound scan preoperatively. Indications for surgical intervention were heavy vaginal bleeding or continuous bleeding lasting > 7 days. The main outcome measure was histological evidence of chorionic villi in surgical specimens.

RESULTS

Among the patients, 109 (85%) had evidence of chorionic villi on histology, whilst decidua was only found in the remaining 19 (15%). There was no identifiable cut-off for endometrial thickness or volume that could be used to differentiate between retained products of conception and decidua.

CONCLUSION

Measurements of endometrial thickness or volume on ultrasound scan are not good tests for diagnosing an incomplete miscarriage.

Design of high affinity cyclic pentapeptide ligands for kappa-opioid receptors

Using results from our previously reported cyclic opioid peptide series and reliable models for mu-, delta-, and kappa-opioid receptors (MOR, DOR, and KOR, respectively) and their complexes with peptide ligands, we have designed and synthesized a series of cyclic pentapeptides of structure Tyr-C[D-Cys-Phe-Phe-X]-NH2, cyclized via disulfide, methylene, or ethylene dithioethers, and where X = D- or L-Cys; or D- or L-penicillamine (Pen; beta,beta-dimethylcysteine). Determination of binding affinities to MOR, DOR, and KOR revealed that members of this series with X = D- or L-Cys display KOR affinities in the low nanomolar range, demonstrating that a 'DPDPE-like' tetrapeptide scaffold is suitable not only for DOR and MOR ligands, but also for KOR ligands. The cyclic pentapeptides reported here are not, however, selective for KOR, rather they display significant selectivity and high affinity for MOR. Indeed, peptide 8, Tyr-C[D-Cys-Phe-Phe-Cys]-NH2-cyclized via a methylene dithioether, shows picomolar binding affinity for MOR ( = 16 pm) with more than 100-fold selectivity for MOR vs. DOR or KOR, and may be of interest as a high affinity, high selectivity MOR ligand. Nonetheless, the high affinity KOR peptides in this series represent excellent leads for the development of structurally related, selective KOR ligands designed to exploit structurally specific features of KOR, MOR, and DOR.

O(6)-methylguanine methyltransferase in colorectal cancers: detection of mutations, loss of expression, and weak association with G:C>A:T transitions

BACKGROUND AND AIMS

O(6)-methylguanine methyltransferase (MGMT) repairs inappropriately methylated guanine in DNA. MGMT mutations have not previously been reported in cancers, but in colorectal tumours MGMT promoter methylation is common and has been associated with increased G:C>A:T transitions, a high frequency of K-ras mutations, and low level microsatellite instability (MSI low). However, some have suggested that MGMT changes are background or secondary events, with little importance for tumorigenesis.

METHODS

We have analysed fresh frozen colorectal cancers and colorectal cancer cell lines for MGMT changes: mutations, allelic loss, and protein expression.

RESULTS

Six of 113 cancers harboured somatic missense MGMT mutations, at least three of which probably caused reduced MGMT function and were accompanied by silencing or loss of the wild-type allele. Cancers with pathogenic MGMT mutations tended to harbour G:C>A:T somatic mutations at other loci. Overall, MGMT expression was reduced or lost in more than half of the cancers. We found no association between MGMT expression and the somatic mutation spectrum at APC, beta-catenin, K-ras, or p53, but decreased MGMT expression was weakly associated with the presence of a G:C>A:T change at any one of these loci. Reduced MGMT expression was not however associated with an increased frequency of K-ras mutations or with MSI low.

CONCLUSION

In summary, we found that mutation of MGMT contributes to decreased protein function. Our findings provide good evidence to show that MGMT changes, including methylation, are selected rather than background events, at least in some cases. Decreased MGMT expression or function probably has a weak or moderate effect on the mutation spectrum in colorectal cancers.

A double-blind placebo controlled randomised trial of misoprostol and oxytocin in the management of the third stage of labour

OBJECTIVE

To compare oral misoprostol 400 microg with intramuscular oxytocin 10 IU in the routine management of the third stage.

DESIGN

Double-blind placebo controlled trial.

SETTING

Main referral hospital and its associated polyclinics in Accra, Ghana.

POPULATION

Four hundred and one low risk women, in the second stage of labour with anticipated vaginal delivery, who entered labour spontaneously.

METHODS

After delivery of the anterior shoulder of the baby, the women were randomised to receive either: 1. misoprostol 400 microg powder in water orally and 1 mL normal saline intramuscular injection (placebo); or 2. powdered cellulose in water orally (placebo) and 1 mL oxytocin 10 IU intramuscular injection.

MAIN OUTCOME MEASURES

Change in haemoglobin concentration from before delivery to 12 hours postpartum. Secondary outcomes included need for additional oxytocics, blood loss > 500 mL and > 1,000 mL, operative intervention for postpartum haemorrhage, and side effects, including nausea, vomiting, diarrhoea, shivering and elevated temperature.

RESULTS

Demographic characteristics were similar. There was no significant difference in change in haemoglobin concentration between the two groups (0.60 g/dL for misoprostol and 0.55 g/dL for oxytocin; relative difference 9.6%; 95% CI 20.5-39.6%; P = 0.54). There were no significant differences in secondary outcomes with the exception of shivering, which occurred more frequently in the misoprostol group (22.2% vs 5.7%; relative risk 4.73; 95% CI 2.31-9.68; P < 0.0001).

CONCLUSIONS

In low risk women oral misoprostol appears to be as effective in minimising blood loss in the third stage of labour as intramuscular oxytocin. Shivering was noted more frequently with misoprostol use, but no other side effects were noted. Misoprostol has great potential for use in the third stage of labour especially in developing countries.