Nutritional Supplement With Fermented Soy in Men With an Elevated Risk of Prostate Cancer and Negative Prostate Biopsies: General and Oncological Results From the Prospective PRAECAP Trial

OBJECTIVE

To investigate the effect of a dietary supplement containing fermented soy on PSA, IPSS, changes in prostate volume and prostate cancer (PCa) development after a 6-month challenge in men at increased risk of PCa and negative previous biopsies. MATERIALS AND METHODS: Patients with an elevated risk of PCa, defined by either 1 of the following criteria: PSA >3 ng/mL, suspect lesion at digital rectal examination (DRE), suspect lesion at transrectal ultrasound (TRUS)/magnetic resonance imaging (MRI) and previous negative prostate biopsies (at least 8 cores) within 12 months before inclusion. Statistical analysis was carried out using a non-parametric 1-sided paired Wilcoxon rank sum test, chi-square test, and Fisher's exact test.

RESULTS

In this trial, 94 patients were eligible for analysis. A PSA response was detected in 81% of the cases. In 25.8% (24/93) of patients, a decrease of at least 3 points on the IPSS was observed. The median prostate volume did not statistically change after 6 months (P = .908). Patients with PSA modulation required fewer investigations and had fewer positive biopsies (P <.001) and significantly fewer ISUP ≥3 lesions (P = .02).

CONCLUSION

We observed a significantly lower PSA level after a 6-month challenge with a fermented soy-containing supplement, and an effect on IPSS in a subset of patients. Prescribing a fermented soy supplement in patients with an increased PCa risk could lead to a better selection of patients at real increased risk of having occult PCa.

Dosimetric Impact of Systematic Mediastinal Staging via Endobronchial Ultrasound for Patients with Locally Advanced Lung Cancer: The SEISMIC Trial

PURPOSE/OBJECTIVE(S)

The SEISMIC trial aims to find the best method for mediastinal staging in patients with lung cancer receiving chemoradiotherapy. Currently, CT or PET-CT scans are standard in clinical practice, but histological evaluation of the mediastinum is performed on a case-by-case basis. The study will examine the effect of systematic histological evaluation using Endobronchial Ultrasound (EBUS) on radiotherapy target volumes. The hypothesis of this study is that differences in staging between the diagnostic PET-CT and EBUS would result in reduced tumor coverage and/or increased doses to organs at risk (OAR).

MATERIALS/METHODS

SEISMIC is a prospective multicenter international cohort study. Patients were enrolled from Australia, the Netherlands, USA and Canada after regional IRB approvals. Patients were treated with 4DCT simulation. Two iGTV and PTV target volumes were delineated for each patient with discordant staging according to both PET-CT and EBUS, as were OARs. Two VMAT plans were generated for each patient based on either PET-CT or EBUS target volumes using knowledge-based planning methodology. Plans aimed to achieve institutional guidelines for target coverage and OAR dose constraints, with a prescribed dose of 60 Gy in 30 fractions. Target coverage and OAR doses for the PET- and EBUS-defined volumes were compared.

RESULTS

In 156 patients, EBUS showed a larger extent of disease than PET in 18 (11.5%) and a smaller extent of lymph node (LN) involvement than PET in 49 (31.4%). Out of 67 patients with PET-EBUS discordant results, 25 underwent upfront radiotherapy and were included in the study. EBUS revealed PET-occult LN involvement in 11/25 patients (44%). In these patients, 10/11 patients received <95% of the prescribed dose to PET-occult LN iGTVs; the median [range] minimum dose to the EBUS iGTV was 9.2 Gy [0.1 - 57.9 Gy]. When planning based on EBUS LN involvement, all patients received ≥95% of the prescribed dose to the iGTV (the median [range] minimum dose to the EBUS iGTV was 58.9 Gy [58.1 - 60.5 Gy]). This resulted in increased median [range] doses to OARs; mean lung dose increased by 1.1 Gy [0.3 - 8.4 Gy], esophagus mean dose increased by 3.6 Gy [0.2 - 24.8 Gy], and mean heart dose increased by 0.5 Gy [-0.6 - 8.5 Gy].

CONCLUSION

Systematic endoscopic evaluation of the mediastinum had a significant effect on tumor coverage in a clinically meaningful proportion of cases and consequent plan adaptation impacted on organ-at-risk (OAR) doses. Results suggest systematic mediastinal LN staging should be considered in all patients prior to curative-intent radiotherapy.

CLINICAL TRIAL ID

ACTRN12617000333314.

E. coli bacterial meningitis after transrectal prostate biopsy under antibiotic prophylaxis: a case report and literature review

Prostate biopsy, a frequently performed procedure, is not harmless. In rare cases, life‐threatening complications occur. We document a potential lethal bacterial meningitis after transrectal biopsy. In addition to our overview of all previously documented cases, we highlight the evidence of prevention of infectious complications when performing a prostate biopsy.

Even after antibiotic prophylaxis, severe infections sometimes follow transrectal prostate biopsy. Involvement of the central nervous system is not well known but demands early recognition. In this situation, intravenous antibiotics with a high penetration through the blood–brain barrier are of vital importance. The most effective preventive measure against infectious complications is to change the biopsy approach to transperineal.

Treatment of patients with newly diagnosed metastatic hormone sensitive prostate cancer (mHSPC) in Belgium: a real world data analysis

INTRODUCTION

Abiraterone acetate + prednisone (AAP) and docetaxel have proven their efficacy in the treatment of patients with newly diagnosed metastatic hormone-sensitive prostate cancer (mHSPC) in clinical trials. However, real-world data are scarce. The goal of this study is to evaluate real-world data on the efficacy and safety of these therapies in mHSPC patients.

PATIENTS AND METHODS

Records of 93 patients from 21 different centres were retrospectively reviewed. Primary and secondary endpoints were radiographic and PSA progression-free survival (RPFS - PSA-PFS) and cancer specific and overall survival (CSS - OS), respectively. Adverse events (AEs) were evaluated according to the Common Terminology Criteria for Adverse Events version 5.0. Differences in oncological outcome and AEs were evaluated between three treatment groups: ADT only (N=26) - ADT + AAP (N=48) - ADT + docetaxel (N=19). Survival analysis was performed using Kaplan-Meier statistics.

RESULTS

Median RPFS was 13 months (95% confidence interval [CI]: 9-17) for ADT only, 21 months (95% CI: 19-23) for ADT + AAP and 12 months (95% CI: 11-14) for ADT + docetaxel (p = 0.004). The 1-year PSA-PFS, CSS and OS were 73.5%, 90.7% and 88.7%, respectively, with no significant differences between the three groups. Adverse events of grade 3 or higher were not observed more frequently.

CONCLUSION

Retrospective real-world data show a significantly longer RPFS for mHSPC patients treated with ADT + AAP compared to ADT only or ADT + docetaxel at short-term follow-up. This can aid in counselling of mHSPC patients in daily clinical practice.

Mucinous cystadenocarcinoma in the renal pelvis: primary or secondary? Case report and literature review

INTRODUCTION

Cystic lesions in the renal pelvis may cause a diagnostic dilemma. These lesions may be benign or (pre)malignant and primary of secondary.

CASE REPORT

A 65-year-old woman presents with a complex cystic mass in the lower pole of the left kidney measuring approximately 16 cm in size and classified as Bosniak type 2F with minimally thickened septa and thick calcifications on non-contrast-enhanced computed tomography. The histopathological findings are consistent with a mucinous cystadenocarcinoma in the renal pelvis. Given the absence of a primary focus and based on clinical and radiological examination, the diagnosis of a primary renal neoplasm is preferred.

DISCUSSION

A review of the literature is performed to evaluate the histological differential diagnosis and confirm the diagnosis. Epidemiology with an overview of available similar cases since 2009, as well as etiological factors, treatment and prognosis was reviewed.

CONCLUSION

Primary renal mucinous cystadenocarcinoma is an exceedingly rare tumor. Histopathology still remains the gold standard for the diagnosis of this tumor. Because of the rarity, secondary involvement from more common sites, such as ovary and gastrointestinal tract, should be thoroughly excluded.

Kidney Stone Dissolution Therapy in Phosphate Stones: A Case Report

Background: Phosphate stones can be divided into struvite (7%), apatite (20%), and brushite stones (2%). They often present as large staghorn calculi and, therefore, can be challenging to treat. Moreover, it is crucial to obtain a stone-free patient to prevent recurrence. Therefore, local chemolysis can be an interesting tool when complete surgical removal of the stone is impossible or as an adjuvant treatment for residual stone fragments after surgery. Case Presentation: We present a case of an 84-year old Caucasian man in whom local chemolysis therapy with a citric acid solution resulted in a rapid reduction of the stone load, making less invasive therapy possible. Conclusion: We describe the procedure, (dis)advantages, and possible indications for local chemolysis.

Phase II open-label study investigating apalutamide in patients with biochemical progression after radical prostatectomy

Apalutamide, a competent inhibitor of the androgen receptor, has shown promising clinical efficacy results for patients with advanced prostate cancer. Here, we describe the rationale and design for the SAVE trial, a multi-center, Phase II study, wherein 202 men with biochemical progression after radical prostatectomy are randomly assigned 1:1 to apalutamide plus salvage radiotherapy (SRT) or androgen-deprivation therapy with an luteinizing hormone-releasing hormone agonist or antagonist plus SRT. The primary objective is to compare sexual function between the two treatment arms based on the expanded prostate cancer index-26 sexual domain score at nine months after start of hormonal treatment. The key secondary objectives are to assess quality of life, to evaluate the safety profile and the short-term efficacy of apalutamide in combination with SRT. ClinicalTrials.gov identifier: NCT03899077.

A prospective randomized controlled multicentre trial comparing intravesical DMSO and chondroïtin sulphate 2% for painful bladder syndrome/interstitial cystitis

Objective

To compare effectiveness of intravesical chondroïtin sulphate (CS) 2% and dimethyl sulphoxide (DMSO) 50% in patients with painful bladder syndrome/interstitial cystitis (PBS/IC).

Materials and methods

Patients were randomized to receive either 6 weekly instillations of CS 2% or 50% DMSO. Primary endpoint was difference in proportion of patients achieving score 6 (moderately improved) or 7 (markedly improved) in both groups using the Global Response Assessment (GRA) scale. Secondary parameters were mean 24-hours frequency and nocturia on a 3-day micturition dairy, changes from baseline in O’Leary-Sant questionnaire score and visual analog scale (VAS) for suprapubic pain.

Results

Thirty-six patients were the intention to treat population (22 in CS and 14 in DMSO group). In DMSO group, 57% withdrew consent and only 6 concluded the trial. Major reasons were pain during and after instillation, intolerable garlic odor and lack of efficacy. In CS group, 27% withdrew consent. Compared with DMSO group, more patients in CS group (72.7% vs. 14%) reported moderate or marked improvement (P=0.002, 95% CI 0.05-0.72) and achieved a reduction in VAS scores (20% vs. 8.3%). CS group performed significantly better in pain reduction (-1.2 vs. -0.6) and nocturia (-2.4 vs. -0.7) and better in total O’Leary reduction (-9.8 vs. -7.2). CS was better tolerated. The trial was stopped due to high number of drop-outs with DMSO.

Conclusions

Intravesical CS 2% is viable treatment for PBS/IC with minimal side effects. DMSO should be used with caution and with active monitoring of side effects. More randomized controlled studies on intravesical treatments are needed.

Hypovolemic Shock Caused by Massive Renal Hematoma After a Third Consecutive Extracorporeal Shockwave Lithotripsy Session: A Case Report

Extracorporeal shockwave lithotripsy (SWL) is a commonly used technique for treating urinary calculi. Although noninvasive, highly effective, and widely accepted, SWL is not without complications. Next to fragmenting the calculi, the surrounding tissue is damaged, which can result in renal hematoma, a well-described complication. In most cases, the collateral tissue damage is mild and resolves with conservative treatment. However, rarely, severe complications may arise. Here we present a case of a 46-year-old male who developed a massive hematoma, both subcapsular and retroperitoneal, after a third consecutive SWL session, resulting in hypovolemic shock. Different probable causes are proposed, of which one cause, the length of the interval between SWL sessions, is not yet studied properly. Probably, short intervals keep the damaged tissue from healing sufficiently, as proposed in our case. Possibly, life-threatening situations can be avoided if more evidence-based guidelines are available.

Conservative bladder management in advanced multiple sclerosis

Anticholinergics and intermittent catheterization are the cornerstones of bladder management in early multiple sclerosis (MS). In advanced MS however, bladder management is based more on tradition than on evidence. Nurses seem to deal with catheter problems and chronic incontinence. Despite the abundant use of indwelling catheters, there is a lack for guidelines on catheter-induced problems. The psychosexual and social impact of bladder problems in advanced MS is often neglected. The international multidisciplinary special interest group on sexual, urological and bowel dysfunction in MS (SUBDIMS) as a special interest group of the Rehabilitation in Multiple Sclerosis (RIMS) was confronted with a high variability in practice and a lack of guidelines. A literature review was prepared during three multidisciplinary expert meetings. This review will be the basis of further initiatives to improve the urological treatment of patients with advanced MS.

Obstetric fistula in a district hospital in DR Congo: Fistula still occur despite access to caesarean section

OBJECTIVE

To study the profile of classification, etiology, and the relation between initial classification, and the results of vesicovaginal fistula surgery in a district hospital in DR Congo.

METHODS

This study was based on the analysis of all consecutive patients being treated for VVF in Kisantu between November 2006 and November 2012. The fistula was classified according to the classification of Waaldijk. The location of VVF and degree of fibrosis were noted. Post-operatively, the first examination of patients took place a few days after catheter removal and subsequent review 2-3 months later. Statistical analysis was done in Graphpad Prism 6.

RESULTS

Among 146 patients with VVF, 117 had a primary fistula. The majority of fistula was type I (56%) followed by type III (21%). The majority underwent a caesarean section (63.4%). The mean duration of labor was 30.7 hr. Delay in getting a caesarean in time was due to difficulties in reaching the hospital in 55%. Overall, the closure rate after the first surgical treatment was 65%. The continence rate of the patients with a successful closure was 63%.

CONCLUSION

VVF can occur after caesarean section because of the prolonged labor that already causes ischemia and necrosis of the bladder wall and vesicovaginal septum before or while the caesarean section is being performed. Access to general hospitals and the management of the pregnant women needs to be improved. Despite a reasonable closure rate of 65%, post-fistula incontinence remains an important clinical problem.

Autonomous contractile activity in the isolated rat bladder is modulated by a TRPV1 dependent mechanism

AIMS

Resiniferatoxin (RTX), a vanilloid compound and agonist of the transient receptor potential channel 1 (TRPV1), is known for its beneficial effects on neurogenic detrusor overactivity. The mainstream rationale for its use is the desensitization of TRPV1 on sensory bladder afferents. However, recent findings showed that TRPV1 is present in other cell types in the bladder. To eliminate the effects of RTX on spinal and central neural circuits, we investigated autonomous contractility in normal and neurogenic rat bladders after treatment with RTX.

METHODS

Female Wistar rats were made paraplegic at vertebral level T8-T9. Animals were intravesically pre-treated with vehicle (ethanol 5%) or RTX (100 nM) and sacrificed after 72 hr. Each bladder was excised and placed in a heated organ bath, where intravesical pressures were measured. Effects on contractile parameters of intravesical volume load, the non-selective muscarinic receptor agonist carbachol (CA) and electrical stimulation (ES) of nerves were studied in both groups.

RESULTS

In RTX-treated normal bladders we found shorter contractions with higher amplitude than in control bladders (P < 0.05). In RTX-treated neurogenic bladders the amplitude and duration of autonomous contractions were increased compared with controls (P < 0.05). Furthermore RTX induced an increased response to CA and to ES (P < 0.05).

CONCLUSIONS

RTX significantly affected the properties of autonomous bladder contractile activity. This provides evidence for local effects of RTX on bladder contractile activity, which are not mediated by afferent neural pathways and which may contribute to the beneficial effects on detrusor overactivity. TRPV1 and TRPV1(+) cells seem to play an important role in (autonomous) bladder contractility.

The presence of Fowler's syndrome predicts successful long-term outcome of sacral nerve stimulation in women with urinary retention

OBJECTIVES

Sacral nerve stimulation (SNS) is an effective treatment for women with urinary retention. Some women present specific electromyography abnormalities of the external urethral sphincter (Fowler's syndrome). The aim of this study was to evaluate whether Fowler's syndrome and psychologic preimplant screening could be predictive factors for long-term success of SNS in women with urinary retention.

METHODS

All patients underwent electrophysiologic and urodynamic studies and voiding charts. A validated psychologic screening questionnaire was used. Women with successful temporary stimulation, received a definitive implant (Interstim Medtronic). They were followed prospectively every 6 months. Failure was defined as recurrent retention needing intermittent or permanent catheterisation.

RESULTS

Sixty-two women were implanted, 30 with Fowler's syndrome, 32 with idiopathic retention. In those with Fowler's syndrome, 26.6% screened positive for somatisation, as did 43.8% in the idiopathic group (not significant [ns]). Screening for depression was positive in 30% and 18.8%, respectively (ns). There was no correlation with outcome. Twenty-eight patients failed: 9 with Fowler's syndromes, 19 without (p=0.04). Kaplan-Meier analysis showed that patients with Fowler's syndrome benefitted significantly longer from SNS (log-rank test, p=0.005).

CONCLUSIONS

The presence of Fowler's syndrome is a positive predictive factor for SNS in female urinary retention. Idiopathic urinary retention patients can benefit as well, but the success might be less predictable. Preimplant psychologic screening, using the Patient Health Questionnaire, does not correlate with long-term outcome of SNS in this population.

Comparison study of autonomous activity in bladders from normal and paraplegic rats

AIM

To identify differences in the pattern of pressure generated by isolated bladders from normal and paraplegic rats.

MATERIALS AND METHODS

Nine female Wister rats were made paraplegic by spinal cord transsection at the vertebral level T8-T9 and sacrificed between D21 and D28. A further group (n = 9) was used as a control group. Each bladder was excised and placed in an organ bath where intravesical pressures were measured. Pressure changes were divided in two well-defined groups: macro-transients and spikes. The effects of intravesical volume load and muscarinic (M) agonists were studied.

RESULTS

We demonstrated a higher frequency, a longer duration, and a higher variance of duration in macro-transients in the neurogenic group. Intravesical volume load influenced the amplitude and frequency of macro-transients in both groups similarly. The effects of the muscarinic (M(2))-selective agonist arecaïdine were different in neurogenic bladder; the effects of the non-selective muscarinic (M)-agonist carbachol were similar in both groups.

CONCLUSION

We showed that the pattern of autonomous activity was significantly different between normal and neurogenic rat bladders. We also found evidence for alterations in the muscarinic response of isolated neurogenic rat bladders. This model offers an exciting new research tool to evaluate the detrusor activity in neurogenic and normal conditions.

Gastrointestinal stromal tumor of the prostate

We present a unique case of an atypical prostate tumor in a 49-year-old man with acute urinary retention. Digital rectal examination revealed a large prostate with a parenchymal mass on the left side. Radiologic imaging showed a 14.2 x 9.6 x 14.0-cm prostatic mass and multiple liver metastases. A pathologic diagnosis of a prostatic gastrointestinal stromal tumor was made and was confirmed by molecular analysis. Therapy consisted of a tyrosine kinase inhibitor, resulting in prostate mass reduction. After 100 weeks, the patient was in good physical condition with a continuing partial response with a reduced mass volume and liver nodules.

Identification of kit positive cells in the human urinary tract

PURPOSE

Analogous to interstitial cells of Cajal in the bowel, functional important networks of interstitial cells could have a role in the complex mechanism of central and peripheral control of urinary tract function. Recently various reports mentioned the presence of interstitial cells in different parts of the urinary tract and in different species. Since important differences among species exist, we performed immunohistochemistry on fresh frozen human tissue to study the presence of interstitial cells in the human urinary tract.

MATERIALS AND METHODS

A total of 65 tissue pieces from all levels of the urinary tract were obtained from 44 patients treated at our institution. Tissue was processed for immunohistochemistry immediately after removal. We performed immunohistochemistry for kit, connexin 43 and VRL1/TRPV2.

RESULTS

Interstitial cells immunopositive for all 3 antibodies were seen beneath the urothelium and between smooth muscle cells in all tissue pieces with slight topographical differences.

CONCLUSIONS

Together with morphological and functional data from other experiments these morphological data suggest that, as in the bowel, networks of interstitial cells might have an important role in the physiology and pathology of the urinary tract. They could be involved in pacemaking or have an integrating role through the modulation of neurotransmission and conduction of electrical impulses. Functional experiments are the next step to study these hypotheses.

Topography of the vanilloid receptor in the human bladder: more than just the nerve fibers

PURPOSE

We determined the presence and distribution of vanilloid receptor-1 in the human bladder and confirmed or rejected previous findings of other groups that used indirect methods or vanilloid receptor-1 antibodies made by immunizing experimental animals. Also, we tested the reproducibility of results using commercially available antibodies against the N-terminus and C-terminus of the vanilloid receptor.

MATERIALS AND METHODS

A total of 11 normal bladder tissue samples were obtained from cystectomy specimens and fresh frozen processed. Specimens were studied by immunohistochemistry and confocal laser microscopy using 3 vanilloid receptor-1 antibodies. Immunohistochemical co-localization studies for neurofilament, neuronal nitric oxide synthase and nerve growth factor were performed.

RESULTS

Our results confirm the presence of vanilloid receptor-1 on nonmyelinated and myelinated nerve fibers. There was vanilloid receptor-1 immunoreactivity on smooth muscle cells but different sensitivities for the antibodies. There was immunoreactivity on interstitial cells located in the suburothelium and intermuscular septa of the muscularis. There was co-localization of neuronal nitric oxide synthase with interstitial cells but not with neurofilament. No co-localization was found for nerve growth factor and vanilloid receptor-1.

CONCLUSIONS

Vanilloid receptor-1 is located on small unmyelinated and myelinated nerve fibers. In addition, vanilloid receptor-1 is also present on interstitial cells in the suburothelium. There is smooth muscle cell immunoreactivity but a difference in antibodies raised against the C-terminus and N-terminus. These data suggest that the current hypothesis about the mechanism of action of vanilloids is through blocking the afferent reflex arc must be revised and the function of interstitial cells deserves further attention.

Assessment of a bronchoscopy simulator

The study objective was to validate a flexible bronchoscopy simulator by determining if it could differentiate between expert and novice bronchoscopists. A subsequent evaluation phase was then done to determine whether use of the simulator would improve the rate of bronchoscopy skill acquisition for new pulmonary fellows. A multicenter prospective cohort study was performed using a bronchoscopy simulator. Three cohorts were evaluated based on the number of bronchoscopies previously performed: "experts" (> 500, n = 9), "intermediates" (25 to 500, n = 8), and "novices" (none, n = 11). Each participant performed two simulated cases with performance measures being recorded by the simulator. Performance measures that distinguished between groups were then used to evaluate the learning curve for new fellows training on the simulator. A randomized-controlled trial was then conducted comparing the quality of bronchoscopy performance for new pulmonary fellows who were trained either with conventional methods or with the simulator. Expert bronchoscopists performed better on the simulator than intermediates who performed better than novices in terms of procedure time, percentage of segments visualized, time in red-out, and wall collisions. Training of new fellows demonstrated that after performing 20 bronchoscopic simulations, the skill level acquired with the simulator significantly improved in terms of speed, percentage of segments visualized, time in red-out, and collisions. Fellows trained on the simulator performed better than fellows trained using conventional methods during their first actual bronchoscopies as assessed by procedure time (815 versus 1,168 s, p = 0.001), a bronchoscopy nurse's subjective quality assessment score (7.7 +/- 0.3 versus 3.7 +/- 2.5, p = 0.05), and by a quantitative bronchoscopy quality score (percentage of segments correctly identified/procedure time, 0.119 +/- 0.015 versus 0.046 +/- 034, p = 0.03). In conclusion, the bronchoscopy simulator was able to accurately assess bronchoscopy experience level. Training new fellows on the bronchoscopy simulator leads to more rapid acquisition of bronchoscopy expertise compared with conventional training methods. This technology has the potential to facilitate bronchoscopy training and to improve objective evaluations of bronchoscopy skills.

The negative predictive value of spiral computed tomography for the diagnosis of pulmonary embolism in patients with nondiagnostic ventilation-perfusion scans

BACKGROUND

There is no noninvasive method to rule out pulmonary embolism when the clinical suspicion for pulmonary embolism is high. We did a prospective observational study to determine the negative predictive value of spiral computed tomography (CT) in this situation.

METHODS

We performed spiral CT scans of the thorax in consecutive patients with high clinical suspicion of pulmonary embolism with intermediate or low probability ventilation-perfusion scans. Patients with negative or indeterminate spiral CT results had conventional angiography at the discretion of the attending physician. Only patients with positive spiral CT results or positive conventional angiograms were treated. All patients were observed for 6 months for evidence of venous thromboembolic disease. Clinical outcome without treatment or the results of conventional angiography were used as reference standards. False-negative results were defined as a negative spiral CT with a positive conventional angiogram or any diagnosis of venous thromboembolism within 6 months.

RESULTS

Among the 103 patients who were studied, spiral CT scans were positive in 22 patients, indeterminate in 10 patients, and negative in 71 patients. Twenty-seven (26%) patients had pulmonary embolism by clinical outcome, including 3 of the 71 patients with negative spiral CT scans and 2 of the 10 patients with indeterminate scans. A negative spiral CT result had a likelihood ratio of 0.12 (95% confidence interval [CI]: 0.04 to 0.35) with a negative predictive value of 96% (95% CI: 88% to 99%). Using conventional angiography only as the reference standard, a negative spiral CT result had a likelihood ratio of 0.08 (95% CI: 0.02 to 0.31) and a negative predictive value of 93% (95% CI: 77% to 98%).

CONCLUSIONS

Spiral CT has a high negative predictive value for pulmonary embolism and may replace conventional angiography in the workup of pulmonary embolism. Patients with indeterminate spiral CT results should be considered for conventional angiography.

Photodynamic therapy: a case series demonstrating its role in patients receiving mechanical ventilation

Photodynamic therapy (PDT) has long been used to treat cancers within the tracheobronchial tree. There have been many reports about the use of PDT for the treatment of carcinoma in situ and for obstructive endobronchial lesions. PDT has not been previously reported in patients receiving mechanical ventilation. PDT offers the advantages of a relatively short duration of treatment, a low side effect profile, and relatively low risk when compared to Nd-YAG laser in patients receiving mechanical ventilation. We report the first successful use of PDT to wean patients from mechanical ventilation.

Photodynamic therapy in lung cancer

Photodynamic therapy (PDT) involves the use of photosensitizing agents that are selectively retained within tumor cells. The agents remain inactive until exposed to light of the proper wavelength. When activated by light, these compounds generate toxic oxygen radicals that result in tumor necrosis. In lung cancer, PDT can be used for both carcinoma in situ and for the treatment of unresectable disease with endobronchial obstruction. For patients with advanced disease, careful patient selection and integration of PDT with other interventional techniques are critical. Limited data suggest that PDT is comparable in efficacy to neodymium-yttrium-aluminum garnet (Nd-YAG) laser therapy, and some evidence indicates that it may be superior in terms of duration of response. For PDT to be used effectively, it should be integrated into a multimodality approach with chemotherapy and radiation. The optimal sequencing of these treatment modalities remains an area for further investigation.

Primary pulmonary melanoma: case report and literature review

Primary pulmonary melanoma is a very rare disease, with only 19 cases previously reported in the English language literature. These cases suggest that melanoma can arise in the lung as a primary tumor, probably from residual melanoblasts. Primary pulmonary melanoma is frequently endobronchial and often manifests with symptoms of cough, hemoptysis, and lobar collapse. Aggressive surgical resection, irrespective of lymph node involvement, offers possible long-term survival in some patients. The diagnosis of primary pulmonary melanoma necessitates that both clinical and histologic criteria be fulfilled. Herein diagnostic criteria are proposed, and the diagnostic approach is discussed.

Independent lung ventilation

Situations in which independent lung ventilation may be of use include massive hemoptysis, pulmonary alveolar proteinosis, risk of interbronchial aspiration, unilateral lung injury, single lung transplant, and BPF. Any decision to attempt independent lung ventilation should take into consideration the many technical difficulties associated with the procedure. They include difficulties in the placement of DLTs and monitoring tube position, the risk of tube displacement, and the risk of airway trauma. The clinician also must consider the costs in terms of available manpower and resources. Maintaining a patient on independent lung ventilation requires highly skilled nursing care, specialized monitoring devices, and readily available FOB. Even with these limitations, independent lung ventilation may be of use in certain clinical situations when standard methods have failed.

Acute sarcoid myositis with respiratory muscle involvement. Case report and review of the literature

A 61-year-old woman with a history of sarcoidosis presented with acute sarcoid myositis affecting the respiratory muscles. The patient responded to prednisone therapy with improved pulmonary function test results and resolution of her symptoms. Acute myositis is a rare manifestation of sarcoidosis and should be treated with steroids.

Failure of dithiothreitol and pronase to reveal a false-positive cryptococcal antigen determination in cerebrospinal fluid

A patient with squamous cell carcinoma of the lung and a serum rheumatoid factor (RF) of 1:1,280 had a positive cerebrospinal fluid (CSF) latex agglutination test (LAT) for cryptococcal antigen, in culture-negative, India-ink-negative CSF. Pretreatment of the sample of CSF with 2-mercaptoethanol (2-ME) ablated the antigen titer and established the presence of a false-positive LAT, whereas CSF pretreated with dithiothreitol (DTT) and pronase continued to yield a false-positive result. The differing ability of pronase, DTT, and 2-ME to eliminate interfering substances from CSF has not been previously described. Moreover, because RF is unlikely to cross the blood-brain barrier, the authors postulated that malignant disease was responsible for the patient's false-positive LAT in CSF. Hence, the authors report the case to emphasize that false-positive LAT results in CSF are unlikely to be produced by RF and to underscore the benefit of using enzymatic and sulfhydryl-reducing agents when the validity of the initial test results are in doubt. Such a procedure will optimize the chances of accurately identifying false-positive LAT results in CSF.

Non-calcium environmental sensitivity of intracellular Indo-1

Several mechanisms might account for the difference between spectra of Indo-1 measured on intracellular and on extracellular dye. Experiments to discriminate between various possibilities used quantitative analyses of intracellular and extracellular Indo-1 spectra. Intracellular calcium-free dye showed a 20-nm blue shift, when compared with the extracellular case. However, the calcium-bound spectrum was unaffected by the intracellular milieu. This eliminated the possibility that the spectral shift was due to calcium-independent unhydrolyzed dye. The spectral shift was reversible and was seen in resting cells as well as calcium-depleted cells. Since the apparent dissociation constant for calcium was not detectably different inside the cell, the possibility of competitive binding to another divalent cation, such as Zn2+, was eliminated as the principle source of the spectral shift. The shift appears to be due to a noncompetitive solvent effect on the emission of the calcium-free dye that is absent in the calcium-bound form.