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.

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.

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.

A multicenter pilot study of a bronchial valve for the treatment of severe emphysema

BACKGROUND

Chronic obstructive pulmonary disease (COPD) affects millions of people and has limited treatment options. Surgical treatments for severe COPD with emphysema are effective for highly selected patients. A minimally invasive method for treating emphysema could decrease morbidity and increase acceptance by patients.

OBJECTIVE

To study the safety and effectiveness of the IBV(R) Valve for the treatment of severe emphysema.

METHODS

A multicenter study treated 91 patients with severe obstruction, hyperinflation and upper lobe (UL)-predominant emphysema with 609 bronchial valves placed bilaterally into ULs.

RESULTS

Valves were placed in desired airways with 99.7% technical success and no migration or erosion. There were no procedure-related deaths and 30-day morbidity and mortality were 5.5 and 1.1%, respectively. Pneumothorax was the most frequent serious device-related complication and primarily occurred when all segments of a lobe, especially the left UL, were occluded. Highly significant health-related quality of life (HRQL) improvement (-8.2 +/- 16.2, mean +/- SD change at 6 months) was observed. HRQL improvement was associated with a decreased volume (mean -294 +/- 427 ml, p = 0.007) in the treated lobes without visible atelectasis. FEV(1), exercise tests, and total lung volume were not changed but there was a proportional shift, a redirection of inspired volume to the untreated lobes. Combined with perfusion scan changes, this suggests that there is improved ventilation and perfusion matching in non-UL lung parenchyma.

CONCLUSION

Bronchial valve treatment of emphysema has multiple mechanisms of action and acceptable safety, and significantly improves quality of life for the majority of patients.

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.