Polymorphisms in the androgen receptor CAG repeat sequence are related to tumour stage but not to ERG or androgen receptor expression in Malaysian men with prostate cancer

INTRODUCTION

Polymorphic expression of a CAG repeat sequence in the androgen receptor (AR) gene may influence the activity of the AR and the occurrence of prostate cancer and the TMPRSS2-ERG fusion event. Furthermore, this polymorphism may be responsible for the ethnic variation observed in prostate cancer occurrence and expression of the ERG oncogene. We investigate the expression of AR and ERG in the biopsies of Malaysian men with prostate cancer and in the same patients relate this to the length of the CAG repeat sequence in their AR gene.

MATERIALS AND METHODS

From a PSA screening initiative, 161 men were shown to have elevated PSA levels in their blood and underwent prostatic tissue biopsy. DNA was extracted from the blood, and exon 1 of the AR gene amplified by PCR and sequenced. The number of CAG repeat sequences were counted and compared to the immunohistochemical expression of ERG and AR in the matched tumour biopsies.

RESULTS

Of men with elevated PSA, 89 were diagnosed with prostate cancer, and 72 with benign prostatic hyperplasia (BPH). There was no significant difference in the length of the CAG repeat in men with prostate cancer and BPH. The CAG repeat length was not associated with; age, PSA or tumour grade, though a longer CAG repeat was associated with tumour stage. ERG and AR were expressed in 36% and 86% of the cancers, respectively. There was no significant association between CAG repeat length and ERG or AR expression. However, there was a significant inverse relationship between ERG and AR expression. In addition, a significantly great proportion of Indian men had ERG positive tumours, compared to men of Malay or Chinese descent.

CONCLUSIONS

CAG repeat length is not associated with prostate cancer or expression of ERG or AR. However, ERG appears to be more common in the prostate cancers of Malaysian Indian men than in the prostate cancers of other Malaysian ethnicities and its expression in this study was inversely related to AR expression.

Heterogenous expression of ERG oncoprotein in Malaysian men with adenocarcinoma of the prostate

INTRODUCTION

Prostate cancer is a heterogenous disease and the mechanisms that drive it to behave differently are not well understood. Tumour expression of the ERG oncogene occurs in the majority of patients with prostate cancer in Western studies. This is considered to be oncogenic as ERG acts as a transcription factor to regulate genes involved in tumour proliferation and invasion. In this study we investigated expression of ERG in Malaysian men with prostate cancer.

METHODS

Tissues were collected from 80 patients with clinically detected prostate cancer and treated with radical prostatectomy. Cases were tested for ERG by immunohistochemistry using the mouse monoclonal antibody EP111. All blocks on 48 cases were tested in order to determine the extent of heterogeneity of ERG expression within individual cases. ERG expression was analysed in relation to patient age, ethnicity and tumour stage and grade.

RESULTS

Forty-six percent of cases were ERG positive. There was no significant association between ERG and tumour grade or stage. Sixty-nine percent of Indian patients had ERG positive tumours; this was significantly higher (p=0.031) than for Chinese (40%) and Malay (44%) patients. Heterogeneity of ERG expression, in which both positive and negative clones were present, was seen in 35% of evaluated cases. Evaluation by tumour foci showed younger patients had more ERG positive tumour foci than older patients (p=0.01). Indian patients were more likely to have the majority of tumour foci with ERG staining positively, compared to either Chinese or Malay patients (P <0.01).

CONCLUSION

In this study, tumour expression of ERG was more likely to occur in patients of Indian ethnicity.

Spontaneous gastro-pancreatic fistula - a hitherto unknown natural history of IPMN?

Intraductal papillary mucinous neoplasm (IPMN) is a distinct group of benign pancreatic neoplasms often discovered incidentally on imaging. Apart from their malignant potential, little is known about their natural history as most are surgically resected. We report an unusual presentation and possible natural history of IPMN in a patient who refused surgery and hence was on regular follow up.

Safety and efficacy of self-expanding removable metal esophageal stents during neoadjuvant chemotherapy for resectable esophageal cancer

Patients with esophageal cancer may present with dysphagia and weight loss. Resectable lesions require consideration of neoadjuvant chemotherapy, which improves survival but have side effects, which compound already poor intake. Prevention of malnutrition has historically required interventions such as surgical jejunostomy or percutaneous endoscopic gastrostomy, which carry associated morbidity. With established roles in palliation, self-expanding removable metal stents (SERMS) may provide an alternative intervention in resectable disease. We sought to evaluate outcomes from our unit's introduction of SERMS in dysphagic patients prior to esophagectomy. All dysphagic patients presenting with esophageal cancer and considered for curative surgery between April 2006 and November 2008 were offered preoperative treatment of dysphagia with SERMS during neoadjuvant chemotherapy. Baseline and preoperative outcomes assessed included dysphagia score and nutritional markers. Sixteen patients underwent esophageal stenting during neoadjuvant therapy of whom 7/16 (44%) were female with mean age 63 (53-76). In 12/16 (75%), tumors were located in the lower one third of the esophagus. There was a significant fall in mean dysphagia score from 2.5 (range 1-4) to 1.1 (range 0-3) immediately preoperatively. There was no significant change in serum albumin, weight, or body mass index. Stent-related morbidity occurred in 4/16 (25%) patients and stomach migration occurred in 7/16 (43.8%). All were resolved endoscopically and there was no stent-related mortality. Of 10/16 (62.5%) patients ultimately progressing to esophagectomy, 30-day mortality was 6.3%. Anastomotic leak occurred in one patient (10%) and R1 resection rate was 20%. SERMS are a safe and effective intervention in dysphagic patients undergoing neoadjuvant chemotherapy for esophageal cancer. Complications are minor and readily treatable with endoscopy. Objective parameters suggest nutritional status is maintained and symptoms are improved. SERMS do not appear to compromise resection.

PleurX drain use in the management of malignant ascites: safety, complications, long-term patency and factors predictive of success

OBJECTIVES

The aim of this article was to assess the success, safety, complication profile and factors associated with long-term patency of tunnelled peritoneal drains (PleurX) in the treatment of refractory malignant ascites.

METHODS

Over a 4-year period, 28 consecutive patients (32 drain insertions) with refractory malignant ascites were treated with a PleurX drain. The study group comprised 7 males and 21 females (mean age, 61 years). A combination of fluoroscopic and ultrasound guidance was used to insert 4 drains; the remaining 28 drains were inserted under ultrasound guidance alone. Patient history, biochemical profiles, pathological and procedural records and clinical follow-up until death were reviewed. Statistical analysis included multivariate logistic regression analysis and Kaplan-Meier curves (p<0.05 was considered significant).

RESULTS

There was a 100% technical success rate for the insertion of the drain; there were no procedure-related deaths and no major complications. Only minor complications were reported: three (10%) immediate; three (10%) early; and two (7%) late. Factors significantly associated with these complications included current chemotherapy, low haemoglobin levels, low albumin levels, high white cell count and high c-reactive protein levels. The length of time the drains remained in situ, and therefore patent, ranged from 5 to 365 days (mean, 113 days). Out of the original 28 tunnelled drains, 24 (86%) remained in situ and functioning until the patients' death. Four (14%) drains dislodged and a subsequent PleurX drain was inserted on the opposite side of the abdominal wall. These new drains remained patent until the patient's death. The annual event rate was 0.45 events per year. A comorbid diagnosis of renal disease or chemotherapy was significantly related to a decreased length of patency.

CONCLUSION

The use of tunnelled peritoneal drains is safe and effective and we would advocate their use as a first-line approach in patients with refractory malignant ascites. Care and regular follow-up is indicated following insertion of the drain in all patients, especially those on chemotherapy and those with a pre-procedure diagnosis of renal disease.

Peritoneal implantation of ureter in a cadaveric kidney transplant recipient

We report here a case of a kidney transplant recipient in whom the ureter was initially implanted into the peritoneum. Excessive ultrafiltration volume and reversal of serum vs dialysate creatinine ratio when the patient was recommenced on continuous ambulatory peritoneal dialysis first suggested the diagnosis which was subsequently confirmed by a plain abdominal x-ray demonstrating placement of ureteric stent in the peritoneum. This rare complication was successfully corrected with surgical re-implantation of ureter into the bladder and 5 years later, the patient remains well with good graft function.

A prospective, randomized, double-blind study comparing lignocaine gel and plain lubricating gel in relieving pain during flexible cystoscopy

OBJECTIVE

To determine the optimum duration for the retention of 2% lignocaine gel intraurethrally as an anaesthetic for flexible cystoscopy in men.

PATIENTS AND METHODS

A prospective, randomized, double-blind, placebo-controlled trial was conducted in two parts. Initially, the importance of duration was determined, i.e. whether pain relief was significantly improved when lignocaine gel was instilled for longer than is currently practised. As pain relief was improved by retaining the lignocaine gel for longer, the optimum time was determined in a second trial. Initially, 90 patients were divided into four groups receiving 20 mL of 2% lignocaine gel or plain lubricating gel for 5 or 25 min. Subsequently, 60 men were divided into two groups receiving 20 ml of 2% lignocaine gel for 15 or 25 min. The patients' discomfort was recorded using a 4-point descriptive pain scale and a 100 mm non-graphical visual analogue scale.

RESULTS

In the first study, those patients receiving lignocaine gel for 25 min experienced significantly less pain than the other three groups. In the second, lignocaine gel in the urethra for 15 min provided the same level of pain relief as lignocaine for 25 min.

CONCLUSION

Pain during flexible cystoscopy can be significantly reduced when 20 mL of 2% lignocaine gel is left in the urethra for 15 min; lignocaine gel would be more effective when left for longer than is currently practised.

Heatstroke: its clinical and pathological presentation, with particular attention to the liver

Heatstroke is a potentially fatal disorder caused by an extreme elevation of body temperature. It is the most severe of the illnesses produced as a result of a high ambient temperature; however, it also may occur sporadically among individuals working or exercising in more favorable weather conditions, particularly early in their training before acclimatization occurs. The liver is a common site of tissue injury in cases of heatstroke and can be the site of fatal tissue injury in cases that survive the initial neurologic injury. Prompt early recognition of heatstroke as the entity responsible for a given patient's problems and effective early cooling with attention to expected complications can result in complete recovery in most cases. In a minority (< 10%) in whom neurologic injury has not resulted in an early death occurring within the first 2-3 days, the hepatic injury due to heatstroke can result in death that occurs a week or more after the onset of the heat stress, unless the liver is replaced. Recently, two such cases have been referred to the University of Pittsburgh for transplantation. On the basis of these two referrals and a review of the literature, we believe that this problem occurs more often than is currently appreciated, principally because of a lack of knowledge about the problem. In an attempt to correct this information deficit, this review was prepared.