Evaluation of power Doppler ultrasonography for prostate biopsy in men with elevated serum prostate specific antigen levels.

OBJECTIVES: To evaluate power doppler ultrasonography (PDU)-directed prostate biopsy in patients with elevated serum prostate specific antigen (PSA) levels. MATERIALS AND METHODS: Men with serum total PSA levels of more than 4 ng/ml undergoing biopsy for the first time were included. Grey-scale transrectal ultrasound (TRUS) and PDU were performed. PDU signal on vascularity accumulation and perfusion characteristics were recorded and graded as normal or abnormal in the peripheral zone of the prostate. Abnormalities were defined on transverse image as radial or arc hypervascularities. A biopsy regime based on Vienna-normogram was performed in all patients. RESULTS: Overall, prostate adenocarcinoma detection rate was 21.4% and abnormal accumulation on PDU signal was identified in 96.7% of those patients (p = 0.01). PDU directed prostate biopsies were positive in 66.7% of the patients with prostate cancer. The sensitivity, specificity, positive predictive value and negative predictive value of PDU signal alone for prostate cancer detection was 96.7%, 24.5% and 96.4% respectively, and PDU guided biopsies were 66.7%, 24.5%, 19.4% and 73% respectively. CONCLUSIONS: The high sensitivity and negative predictive value of PDU makes it useful as an aid for TRUS biopsy in selected patient with previous negative biopsies at risk of harbouring prostate cancer.

Killian-jamieson diverticulum: the rarer cervical esophageal diverticulum.

Killian-Jamieson (K-J) diverticulum is a rare cervical oesophageal diverticulum, less commonly encountered compared with Zenker's diverticulum (ZD). We report a case of K-J diverticulum in a 52-year-old lady who presented with sensation of lump in the neck and food stuck in the throat of 5 years duration. Esophagogram showed a large rightsided pharyngoesophageal diverticulum which was confirmed on endoscopy. The patient underwent a diverticulopexy and recovered without complications. Her symptoms had improved. In this report, we review the literature and describe our surgical technique.

Duodenal adenocarcinoma arising from a pyloric gland adenoma with a brief review of the literature.

Pyloric gland-type adenoma of the duodenum with documented malignant progression is rare. A case is presented of an 87-year-old man with bloating and nausea, who on investigation was found to have a polyp on the anteroinferior wall of the duodenal cap. Histologic examination of the polyp showed features of a pyloric gland adenoma (PGA) demonstrating the full spectrum of progression from low- to high-grade dysplasia and finally invasive adenocarcinoma. The carcinoma showed gastric-type differentiation highlighted by its mucin immunohistochemistry profile and was of advanced stage with lymph node metastasis. The literature on PGAs and the little documentations on progression to carcinoma in duodenal PGAs are reviewed.

Radical radiotherapy with high-dose-rate brachytherapy for uterine cervix cancer long-term results.

The aim of this is to report the results of radical radiotherapy in carcinoma of the cervix treated by high-dose rate (HDR) intracavitary brachytherapy and external beam radiotherapy (XRT) at a single centre in Singapore. This is a retrospective analysis of 106 consecutive cases with histologically proven cervical cancer, treated by HDR brachytherapy and XRT at the Mount Elizabeth Hospital from 1990 to 1993. External beam radiotherapy to the pelvis was delivered with 6 MV photons, to 45-50.4 Gy in 1.8 Gy fractions. High-dose-rate brachytherapy comprised two to three applications of an intrauterine tandem with paired ovoids, to a median dose of 18 Gy to point 'A', carried out during XRT. All 106 patients completed treatment. Their ages ranged from 32 to 80 years (median 57 years). Most patients presented with stage II or III disease (44 and 37%, respectively) and with squamous cell carcinoma (91%). Median follow-up time was 59 months (range 2-169 months). The 5-year relapse-free survival rate across all stages was 71%. The corresponding overall survival rate was 69%. Local control was achieved in 86 patients (81%); six patients had residual disease (6%), and 14 patients had local recurrence (13%). Fourteen patients developed metastatic disease (13%). On univariate analysis, tumour stage, haemoglobin level, number of brachytherapy treatments and overall treatment time were found to be prognostic factors for overall survival. Late complications were mild (Radiation Therapy Oncology Group score 1-2), except for one patient with grade 4 rectal toxicity. The complication rates were 8, 14 and 45%, respectively, for the rectum, bladder and vagina (stenosis). The use of two to three fractions of HDR intracavitary brachytherapy in addition to pelvic XRT achieves good outcomes.

Performance of silicon nanocrystal non-volatile memory devices under various programming mechanisms.

Non-volatile memory devices based on silicon nanocrystal synthesized with very low energy Si+ implantation are fabricated. Memory performance under various programming mechanisms including Fowler-Nordheim (FN), drain-bias channel-hot-electron (DCHE), and source-bias channel-hot-electron (SCHE) has been investigated. It is observed that the DCHE yields the largest memory window among the three programming mechanisms. The DCHE and SCHE have similar endurance characteristics, but the SCHE has a longer retention time than the DCHE. Both the DCHE and SCHE have a larger memory window, a better endurance and a longer retention time as compared to the FN. Explanations to the phenomena are given.

2nd FY Khoo Memorial Lecture. Brachytherapy--one man's meat, a personal journey in radiation oncology.

The Lecture covers the author's personal experience in brachytherapy in radiation oncology, beginning with low-dose rate (LDR) treatments using 226Ra "hot" sources, in the 1960s and early 1970s, through manual afterloading for treating gynaecological cancers with the same sources in the 1970s and 1980s, to high-dose rate (HDR) remote afterloading on a microSelectron HDR machine, from 1989 on. This progression in brachytherapy is discussed, and specific applications to various tumour sites are presented, including long-term results of a personal series of 106 patients with cancer of the uterine cervix, treated with radiotherapy incorporating HDR brachytherapy. The Lecture rounds off with an unusual case of equine sarcoid, treated with a postoperative implant, using 192Ir LDR brachytherapy.

Microengineering as a tool to study substratum modulation and cell behaviour.

This research is an investigation of the means by which geometrical parameters (e.g. area and shape) and various surface attributes (materials and surface finish) of microengineered structures can modulate cellular response. This is based on biological observations indicating that: (i) the response of tissue cells to injury is determined by the net signal transduction response elicited by soluble regulatory molecules (e.g. cytokines), (ii) common matrix constituents (e.g. collagen) directly affect cell behaviour by the same signal transduction mechanisms mediating cytokine bioactivity, (iii) cellular response to cytokines is modulated by the precise nature of the extracellular matrix to which the target cells are adherent, including its biochemical composition and physical structure.

Internal ureteric stenting following pyeloplasty reduces length of hospital stay in children.

The advent of totally internal ureteric stents has the potential to reduce hospital stay in paediatric pyeloplasty. Traditionally, discharge from hospital has followed removal of an external trans-anastomotic drain, usually 5 days to a week post-operatively. The use of totally internal catheters negates the need for nursing supervision by removing external attachments that a paediatric patient might inadvertently dislodge. The length of hospital stay for pyeloplasty using a Double-J ureteric stent was compared with our previous method of trans-anastomotic feeding tube nephrostomy drainage. The results show the use of Double-J stenting to be advantageous in paediatric pyeloplasty by decreasing considerably the length of hospital stay. This is clearly of benefit to the patient, who returns to the family setting much earlier. Despite the need for an outpatient endoscopic procedure to remove the stent, savings in treatment costs and improved efficiency of bed use are also achieved.

Central venous thrombophlebitis diagnosed by computerized tomography scanning.

A case is described in which computerized tomography scanning aided in a prompt diagnosis and assessment of an intravenous catheter-induced septic thrombus. Computerized tomography scanning detected gas bubbles within the thrombus, which extended from the right subclavian vein into the superior vena cava, and retrograde propagation of the thrombus into the right internal jugular vein. Computerized tomography scanning also helped in the assessment of the amount of deep tissue swelling present and the competence of the upper respiratory tract.

Radical radiotherapy for carcinoma cervix--preliminary experience with the microSelectron high dose rate machine.

Radiotherapy for uterine cervix carcinoma is an accepted treatment for all stages of invasive malignancy. The radiation modality is usually a combination of brachytherapy and external beam therapy for all except the most extensive tumours (stage IV--FIGO). Satisfactory results have been obtained in the Singapore General Hospital using low dose-rate radium applications in combination with cobalt teletherapy. Five year actuarial survival rates of 86.7% were obtained for FIGO stage I, 65.0% for stage II, 41.4% for stage III, 4.9% for stage IV with an overall rate of 54.0% for all stages. Corresponding 10-year rates were: 79.6%, 60.2%, 35.2%, 0% and 48.2%. Preliminary results of primary radiotherapy in 36 patients with cervical carcinoma treated by high dose-rate brachytherapy (microSelectron HDR) combined with 6MVP photons from a Siemens linear accelerator are presented. The patients were registered at the Mount Elizabeth Oncology Centre from November 1989 to December 1990 inclusive. The morbidity from high dose-rate therapy appears lower (9.1% for vaginal stenosis, 6.1% for non-severe proctitis) than for the radium series (4.1% and 20.8%) although the major complication rate appears similar (3% vs 2.8% respectively). The total failure rate is also lower at 19.4% for the HDR patients compared to 33.5% for the radium group. However, these rates are not strictly comparable as the HDR series consists of a small number of patients with limited follow-up. In the light of the data indicating acceptable morbidity with significant rate of early failure, the HDR brachytherapy doses have been increased whilst keeping within the limits set by other centres.

Bone scintigraphy in nasopharyngeal carcinoma.

One hundred and forty-three patients (Group 1) with histologically proven nasopharyngeal-carcinoma (NPC) had bone scintigraphy with 99Tcm methylenediphosphonate (MDP) or dihydroxypropanediphosphonate (DPD) within 2 months of the initial diagnosis. A further 162 patients (Group 2) had bone scans during the course of follow-up if there were symptoms of bone pain or evidence of metastases at other sites. Twenty-three per cent (33/143) of the newly diagnosed NPC patients (Group 1) had evidence of bone metastases. Of these 143 patients, 101 were T0-T2, 16 were T3 and 25 were T4. Thirty-six patients had no neck nodes (NO), 44 were N1, 25 N2 and 38 N3. Of the 162 patients in Group 2, 96 (59%) had a positive bone scan. The commonest sites for bony metastases from NPC were the spine, ribs, pelvis and lower limbs in order of frequency. There is a highly significant association with the nodal stage but no association with the UICC T staging which is not adequate in nasopharyngeal carcinoma. In our part of the world, bone metastases from NPC are a common cause of an abnormal bone scan.

Lung cancer metastases--management.

Distant metastases from lung cancer is a common occurrence in a common malignancy. Almost every organ may be involved but the extra-thoracic sites posing common clinical problems are brain metastases, cord compression, painful bone metastases or pathological fractures, nodal spread and liver involvement. A review of the records of 225 lung cancer patients referred to the Therapeutic Radiology Department, Singapore General Hospital, during the calender year 1985 showed a metastatic rate of 13.8% at referral. On subsequent follow up, an additional 49 patients (21.7%) developed metastases clinically. The organs involved were bone (21 patients), spinal cord (21 patients), brain (18 patients), liver (13 patients), other lung (7 patients) and other sites (17 patients). The management of metastases to the brain, bone and liver, and spinal cord compression will be discussed.

Conservation breast treatment: a viable option locally.

Conservation treatment in carcinoma of the breast is a viable option in the West but is still an uncommon practice locally. Many reasons have been put forth, including the late stage of the tumour we see and the small breast size. This paper presents 25 cases treated by lumpectomy and irradiation with satisfactory cosmetic results, although the follow-up period is short. The introduction of this technique may encourage women to seek treatment earlier, without the fear of losing their breasts.

Hyperthermia with radiotherapy.

The use of hyperthermia together with radiotherapy in the treatment of relatively radioresistant tumours has been widely studied. In this preliminary non control study we used a 8MHz RF capacitive heating machine together with temperature probes inserted into the tumours under local anaesthesia. 27 patients with advanced post-radiation tumour recurrences as well as known radioresistant tumours were selected for treatment with hyperthermia and radiation. 7 patients withdrew from the study because of their intolerance to heat. 3 patients received superficial skin burns. Of the 20 patients studied, we were able to obtain moderate hyperthermia in most cases. 2 patients showed complete responses and 13 partial responses, giving rise to a total response rate of 75%. Some of the technical difficulties in achieving satisfactory hyperthermia are discussed. These include insertion of multiple probes into the body and the problem of achieving uniform heating of the tumour. Advances in hyperthermia can be expected with the development of improved methods of heat delivery and temperature measurements. However, presently methods of heat delivery can be improved by careful adjustment of the heating applicators and manipulation of cooling pads to avoid areas of excessive heating. Further clinical trials should be carried out to establish the optimum technique of hyperthermia.