Faculty Bibliography

OBJECTIVES: Minimally invasive endoscopic treatment of emphysema could provide palliation with less risk than lung volume reduction surgery and offer therapy to patients currently not considered for lung volume reduction surgery. The Intrabronchial Valve is used to block bronchial airflow in the most emphysematous areas of lung. METHODS: Patients with severe chronic obstructive pulmonary disease and heterogeneous upper lobe-predominant emphysema were eligible. Patients underwent flexible bronchoscopic placement of valves into segmental or subsegmental airways in both upper lobes. Outcomes assessed over a minimum of 6 months of follow-up included the safety, feasibility, tolerance, and success of valve placement; health-related quality of life; exercise capacity; pulmonary function; and gas exchange. RESULTS: Five centers treated 30 patients. Patient follow-up ranged from 1 to 12 months. A mean of 6.1 valves were placed per patient. Valves were positioned by means of flexible bronchoscopy in 99% of desired airways, and the procedure duration ranged from 15 to 125 minutes (mean, 65 minutes). Hospital discharge occurred within 2 days in 27 of 30 patients. There were no deaths or episodes of valve migration, tissue erosion, or significant bleeding. Eighty-three percent of patients had no adverse events judged probably or definitely related to the device. Patients experienced significant improvement in health-related quality of life, although the physiologic and exercise outcomes did not show statistically significant improvements. CONCLUSIONS: These first multicenter results with the Intrabronchial Valve demonstrate significant improvements in health-related quality of life and acceptable safety, ease of use, and procedural complication rates. The valve might be a safer and less-invasive alternative to surgical therapy for patients with severe emphysema

BACKGROUND: Severe airway obstruction can occur in the setting of benign granulation tissue forming at bronchial anastomotic sites after lung transplantation in up to 20% of patients. Many of these benign lesions respond to stent placement, laser ablation, or balloon bronchoplasty. However, in certain cases, proliferation of granulation tissue may persist despite all therapeutic attempts. This study describes a series of refractory patients treated with high-dose-rate (HDR) brachytherapy for benign proliferation of granulation tissue, causing airway compromise. METHODS AND MATERIALS: Between April 2002 and June 2005, 5 patients with significant airway compromise from recurrent granulation tissue were treated with HDR brachytherapy. All patients had previously failed to maintain a patent airway despite multiple bronchoscopic interventions. Treatment was delivered using an HDR brachytherapy afterloader with (192)Ir. Dose prescription was to a depth of 1 cm. All patients were treated weekly, with total doses ranging from 10 Gy to 21 Gy in two to three fractions. RESULTS: The median follow-up was 12 months. All patients experienced a reduction in therapeutic bronchoscopic procedures after HDR brachytherapy compared with the pretreatment period. With the exception of possible radiation-induced bronchitis in 1 patient, there were no other treatment related complications. At the time of this report, 2 patients have died and the other 3 are alive with marked symptomatic improvement and reduced bronchoscopic procedures. CONCLUSION: High-dose-rate brachytherapy is an effective treatment for benign proliferation of granulation tissue causing airway obstruction. The early response to therapy is encouraging and further follow-up is necessary to determine long-term durability and late effects.

Peritoneal mesothelioma is a rare cancer of the peritoneum with about 250 new cases diagnosed each year in the United States. It is the second most common site for mesothelioma development and accounts for 10-20% of all mesotheliomas diagnosed in the United States. A meeting sponsored by the NIH Office of Rare Diseases was held in Bethesda, Maryland on September 13 and 14, 2004. The objective of this meeting was to review the epidemiology, biology and current surgical and medical management of peritoneal mesothelioma. In addition, the meeting also discussed clinical and pre-clinical evaluation of novel treatments for mesothelioma as well as ongoing laboratory research to better understand this disease. This report summarizes the proceedings of the meeting as well as directions for future clinical and basic research

Background A 47-year-old woman with a history of ovarian cancer and a 6-year disease-free remission presented with dyspnea and increased abdominal girth. The patient was found to have ascites and a large left pleural effusion, both of which contained malignant cells consistent with recurrent ovarian cancer. Her disease progressed despite treatment with chemotherapeutic and hormonal agents. She was then enrolled in a phase I clinical trial of adenoviral-mediated interferon beta gene therapy. Investigations Abdominal and chest CT scans, 2-[(18)F]fluoro-2-deoxyglucose PET scan, viral cultures, interferon cytokine analysis, immunophenotyping, and tumor cytotoxicity analyses. Diagnosis Stage IV ovarian cancer with malignant ascites and pleural effusion. Management Tunneled pleural catheter and intrapleural adenoviral-mediated interferon beta gene therapy.

Tumor vaccines composed of autologous tumor cells genetically modified to secrete granulocyte-macrophage colony-stimulating factor (GM-CSF) (GVAX) have demonstrated clinical activity in advanced-stage non-small-cell lung cancer (NSCLC). In an effort to remove the requirement for genetic transduction of individual tumors, we developed a 'bystander' GVAX platform composed of autologous tumor cells mixed with an allogeneic GM-CSF-secreting cell line. We conducted a phase I/II trial of this vaccine (3-12 biweekly vaccinations) in advanced-stage NSCLC. Tumors were harvested from 86 patients, tumor cell processing was successful in 76, and 49 proceeded to vaccination. The most common toxicity was local vaccine injection site reactions. Serum GM-CSF pharmacokinetics were consistent with secretion of GM-CSF from vaccine cells for up to 4 days with associated transient leukocytosis confirming the bioactivity of vaccine-secreted GM-CSF. Evidence of vaccine-induced immune activation was demonstrated; however, objective tumor responses were not seen. Compared with autologous GVAX vaccines prepared by transduction of individual tumors with an adenoviral GM-CSF vector, vaccine GM-CSF secretion was approximately 25-fold higher with the bystander GVAX vaccine used in this trial. However, the frequency of vaccine site reactions, tumor response, time to disease progression, and survival were all less favorable in the current study.

Adenoviral immuno-gene therapy using interferon-beta has been effective in an orthotopic model of lung cancer. However, pulmonary inflammation induced by adenoviral (Ad) vectors will almost certainly limit the maximally tolerated dose. On the other hand, the strong innate immune response generated by the vector may be helpful in initiating the adaptive immune response required for efficacy. The goals of this study were to develop an effective approach to inhibit Ad.IFNbeta-mediated acute pulmonary inflammation and to determine whether this reduction of Ad-mediated inflammation decreased the therapeutic efficacy of Ad.IFNbeta in a mouse model of bronchioloalveolar cancer. Our data show that anti-TNF-alpha antibodies can blunt the innate pulmonary immune response induced by Ad vectors, even in sensitized animals. However, this effect also inhibited the ability of the animal to generate anti-tumor immune responses and reduced survival in an orthotopic lung cancer model responsive to Ad.IFNbeta treatment. Interestingly, in a flank model of tumor using a cell line derived from the lung tumor, TNF-alpha blockade did not inhibit efficacy. These data suggest that the innate immune response to adenovirus in the lung may be important in immuno-gene therapy of lung cancer. Therapeutic application of anti-inflammatory therapy in immuno-gene therapy strategies should thus be undertaken with caution.

BACKGROUND AND OBJECTIVE: Transbronchial needle catheters are commonly used during flexible and rigid bronchoscopy for needle aspiration. The use of these catheters can be expanded by employing the technique of transbronchial needle injection. METHODS AND RESULTS: By injecting lesions in the airways, peribronchial structures, mediastinum, or lung parenchyma, transbronchial needle injection has been applied to the treatment of lung cancer, inflammatory disorders of the airways, recurrent respiratory papillomatosis, as well as bronchopleural fistulas. Diagnostic applications have included the localization of peripheral lung nodules as well as sentinel lymph nodes. CONCLUSIONS: Our review defines this bronchoscopic technique and summarizes its various reported applications.

Gene therapy for mesothelioma is currently in its adolescence. The expansion of knowledge regarding molecular aspects of mesothelioma carcinogenesis has facilitated the development of promising gene therapy modalities that target specific oncoproteins and mutant tumor suppressor genes. Although implementation of any of these gene therapy approaches as part of standard medical care for patients who have mesothelioma remains years in the future, the field is finally progressing toward more definitive phase II/III efficacy studies. Unfortunately, the marginal benefits garnered from standard anticancer treatments in mesothelioma argue strongly for continued participation in clinical studies of various experimental approaches, particularly gene therapy. These trials serve multiple purposes: to establish safety, determine proper dosing, evaluate for efficacy, and, in an iterative fashion, guide future avenues of laboratory investigation.

PURPOSE: Delineation of the long-term follow-up data on a series of patients with malignant mesothelioma, who received a single intrapleural dose of a nonreplicative adenoviral (Ad) vector encoding the herpes simplex virus thymidine kinase "suicide gene" (Ad.HSVtk) in combination with systemic ganciclovir. EXPERIMENTAL DESIGN: This report focuses on the 21 patients receiving "high-dose" therapy, defined by an intrapleural dose of vector (> or =1.6 x 10(13) viral particles), where transgene-encoded tk protein was reliably identified on immunohistochemical staining. In 13 patients, the vector was deleted in the E1 and E3 regions of the Ad; in the other eight patients, the vector had deletions in the Ad genes E1 and E4. Safety, immunologic responses, transgene expression, and clinical responses were evaluated. RESULTS: Both the E1/E3-deleted vector and the E1/E4-deleted vector were well tolerated and safe, although production of the E1/E4 vector was more difficult. Posttreatment antibody responses against the tumors were consistently seen. Interestingly, we observed a number of clinical responses in our patients, including two long-term (>6.5 year) survivors, both of whom were treated with the E1/E4-deleted vector. CONCLUSIONS: Intrapleural Ad.HSVtk/ganciclovir is safe and well tolerated in mesothelioma patients and resulted in long-term durable responses in two patients. Given the limited amount of gene transfer observed, we postulate that Ad.HSVtk may have been effective due to induction of antitumor immune responses. We hypothesize that approaches aiming to augment the immune effects of Ad gene transfer (i.e., with the use of cytokines) may lead to increased numbers of therapeutic responses in otherwise untreatable pleural malignancies.