Faculty Bibliography

Modern cancer immunotherapies represent a major shift in paradigm with respect to how we understand innate and adaptive responses to malignancy. Successful tumors co-opt normal immunosurveillance mechanisms by potent interactions between the tumor and local draining lymph nodes. Tumor cells mediate a complex and dynamic immunoediting procedure that results in increased vascular efflux into the draining lymphatics, an immunosuppressive microenvironment rich in regulatory T-lymphocytes, dysfunctional antigen presentation, and downregulation of normal effector lymphocyte responses. Our current approach to reversing this process for antitumor effect involves mainly systemic administration of immunotherapeutic agents, many of which have become standard of care in the management of a variety of cancers. Despite this, we are still learning how best to administer these drugs alone and in combination to maximize efficacy while minimizing adverse events. Increasing evidence suggests that comparable efficacy may be achieved by local administration of immunotherapies in the tumor or tumor-draining lymph nodes with substantially lower doses and better tolerability, even with combination therapy. Herein, we review the literature on intratumoral and intranodal immunotherapies in preclinical models and early-phase studies, with particular emphasis on approaches potentially suitable for translation to larger-scale clinical trials.

Background: GMCI is a tumor-specific immune-stimulator through local delivery of aglatimagene besadenovec, an adenovirus-based vector expressing the HSV-1 thymidine kinase gene (AdV-tk) followed by antiherpetic prodrug. We conducted a phase I dose escalation trial of intrapleural administration of aglatimagene besadenovec followed by standard chemotherapy in patients with MPE. Method: The primary end-point of this dose escalation trial was safety. Eligibility included patients with MPE or MPM with a clinical indication for placement of pleural catheter, age >= 18 yrs, ECOG PS 0-1, FEV1> 40% predicted and adequate end organ function. Intra-pleural (IP) AdV-tk was administered at doses of 1x10¹² viral particles (vp) (Cohort 1); 1 x10¹³ vp (Cohort 2); and 1 x10¹³ vp plus celecoxib (Cohort 3). Three patients were treated per cohort with 10 patients in the expansion phase. Valacyclovir (2 gm PO TID x 14 days) started the day after AdV-tk followed by chemotherapy. Secondary end-points included response rate, progression free survival, overall survival and immune response. Result: From 2013 to 2015, 19 patients were enrolled and completed therapy: median age 69.5 years (range 41-89), 14 malignant mesothelioma (MM) (9 epithelioid, 3 sarcomatoid, 2 biphasic), 4 non-small cell lung cancer (NSCLC) and 1 breast cancer. Eight patients received IP AdV-tk upon diagnosis, 7 prior to 2nd line and 4 prior to 3rd line chemotherapy. Safety results have previously been reported. Response according to RECIST was evaluable for 17 pts. Best response was PR in 4 patients (3 with MM, and one pt with NSCLC), 9 SD and 4 PD. As of 05/2017, three patients are alive and in active follow up (one with NSCLC, and 2 with MM), range of follow up 21-32 months. Of the 4 patients with NSCLC, 3 had prolonged disease stabilization (median overall survival 25.7 months post-GMCI), and one patient is still alive 3.6 years from initial diagnosis (29 month post-GMCI). Conclusion: We previously reported that GMCI can be safely administered at high-doses IP in combination with chemotherapy. With median follow up of 31 months, we report that the majority of the patients experienced clinical benefit and sustained disease stabilization was seen in patients with NSCLC. Three patients are still alive and in active follow up. Phase II studies are warranted to further determine efficacy based on these preliminary encouraging observations; NCT01997190

Background: There is growing appreciation for the role of tumordraining lymph nodes (TDLN) in the dynamic of immuno-editing orchestrated by non-small cell lung cancers (NSCLC). By comparing Tcell subsets and gene expression in TDLN and non-draining lymph nodes (NDLN), we aim to determine whether there is tumor-regional variation in immunophenotype. Method: Patients undergoing endobronchial ultrasound-guided transbronchial needle aspiration for the diagnosis/staging of NSCLC were recruited. Aspirates were obtained from TDLN (N1/N2 nodes with increased fluorodeoxyglucose-F-18 (FDG) avidity and/or enlarged >1cm) and NDLN (non-enlarged/non- FDG-avid N2/N3 nodes) along with peripheral blood. Samples were stained with fluorophore-conjugated antibodies (CD4-FITC, CD8-V450, CD25-PECy7, CD127-APCR700, CD45RO-PECF594) and analyzed by flow cytometry. CD4+CD25- and CD8+ effector T-cells (Teff) were sorted. Gene expression profiling was performed on sorted Teff using the NanostringTM platform to measure differential expression between TDLN and NDLNs. Result: We compared T-cell subpopulations in TDLN and paired NDLN from 16 subjects. There were significantly fewer CD4+ T-cells in TDLN vs NDLN (10.1% vs 28.9%, p=0.0039), with more Tregs (12.1% vs 7.3%, p=0.1563) suggesting a pattern of tumorregional immunosuppression in the TDLN. This was more consistent when tumor histology was adenocarcinoma compared to squamous cell cancer with respect to both depletion of Teff and higher proportion of Tregs (Fig 1). A more immunosuppressive TDLN phenotype was also observed with high tumor PD-L1 expression (>50%), with 36% fewer CD4+ T-cells in TDLN relative to paired NDLN when PD-L1 expression was high relative to just 3.2% fewer CD4+ T-cells with low PD-L1 expression. Gene expression in Teff has preliminarily demonstrated upregulation of genes mediating T-cell exhaustion (CTLA-4, PD-1, TGFb) and downregulation of co-stimulatory/recruitment factors (CD28, ICOS, ICAM2) in TDLN suggesting impaired activation of tumorregional Teff. Conclusion: Our findings suggest that TDLNs in patients with NSCLC display a tolerogenic phenotype, with more marked immunosuppression in the setting of adenocarcinoma and high tumor PD-L1 expression. (Figure Presented)

In the past decade, immunotherapy has emerged as a new treatment modality in cancer. The most success has been achieved with the class of checkpoint inhibitors; antibodies which unleash the anti-tumor immune response. Following the success in melanoma, numerous clinical trials are being conducted investigating checkpoint inhibitors in lung cancer and mesothelioma. The programmed death protein 1-protein death ligand 1/2 (PD-1 - PD-L1/2) pathway and cytotoxic T-lymphocyte associated protein 4 (CTLA4) are currently the most studied immunotherapeutic targets in these malignancies. In non-small cell lung cancer (NSCLC), anti-programmed death receptor -1 (PD-1) antibodies have become part of the approved treatment arsenal. In small cell lung cancer (SCLC) and mesothelioma the efficacy of checkpoint inhibition has not yet been proven. In this concise clinical review, an overview of the landmark clinical trials investigating checkpoint blockade in lung cancer and mesothelioma is provided. Since response rates are around 20% in the majority of clinical trials, there is much room for improvement. Predictive biomarkers are therefore essential to fully develop the potential of checkpoint inhibitors. To increase efficacy, multiple clinical trials investigating the combination of CTLA4 inhibitors and PD-1/PD-L1 blockade in lung cancer and mesothelioma are being conducted or underway. Given the potential benefit of immunotherapy, implementation of current and new knowledge in trial designs and interpretation of results is essential to move forward.

RATIONALE: Transbronchial cryobiopsy is an emerging technique for obtaining biopsies of lung parenchyma. Despite limited evidence of safety and efficacy in direct comparison to other available biopsy procedures, pulmonologists are integrating this technique into clinical practice with the hope of avoiding the risks of surgical lung biopsy. OBJECTIVES: To report the rate of severe complications and diagnostic outcomes immediately after introduction of transbronchial cryobiopsy into the clinical practice of a single-center, high-volume, interventional pulmonary group at a large academic medical center in the United States. METHODS: Retrospective review of a case series. RESULTS: Twenty-five consecutive patients underwent transbronchial cryobiopsy for a variety of indications over a period of 14 weeks. In the absence of a strict protocol, a variety of techniques was employed by four attending interventional pulmonologists and one advanced interventional pulmonology fellow to plan and complete the procedures. Three patients (12%) experienced serious hemorrhage immediately after biopsy, including one patient who survived a life-threatening bleed. Two procedures were complicated by an iatrogenic pneumothorax. One patient experienced hypercapnic respiratory failure shortly after the procedure. A definitive diagnosis was made on 14 cryobiopsies (56%). Another 5 biopsies (20%) contributed to a presumptive diagnosis achieved by multidisciplinary consensus. CONCLUSIONS: Transbronchial cryobiopsy may have diagnostic and safety limitations that are not yet well appreciated given the state of the published medical literature. Major questions remain regarding the safest procedural protocol to be used when performing transbronchial cryobiopsy. Thorough planning and a high degree of caution are encouraged on first introduction of this technique into a clinical practice.

The detection of peripheral lung nodules is increasing due to expanded use of computed tomography (CT) and implementation of lung cancer screening recommendations. Although surgical resection of malignant nodules remains the treatment modality of choice at present, many patients are not surgical candidates, thus prompting the need for other therapeutic options. Stereotactic body radiotherapy (SBRT) and percutaneous thermal ablation are emerging as viable alternatives to surgical resection. For safety, efficacy, and cost-effectiveness purposes, however, alternative bronchoscopic methods for treatment of peripheral lung cancer are currently under active exploration. We searched the Cochrane Library and Medline from 1990 to 2015 to provide the most comprehensive review for bronchoscopic treatment of malignant lung nodules. We used the following search terms: bronchoscopy; lung nodule; peripheral lung lesion; and bronchoscopic treatment. We focused on peripheral pulmonary nodules that are confirmed or highly likely to be malignant. Seventy-one articles were included in this narrative review. We provide herein an overview of advanced bronchoscopic modalities that have been utilized or are under active investigation for definitive treatment of malignant pulmonary nodules. We concisely discuss the use of direct intratumoral chemotherapy or gene therapies, transbronchial brachytherapy, bronchoscopy-guided radiofrequency ablation, placement of markers to guide real time radiation and surgery, cryotherapy and photodynamic therapy. We also briefly report on emerging technologies such as vapor ablation of lung parenchyma for lung cancers. Advances in bronchoscopic therapy will bring additional treatment options to patients with peripheral lung malignancies, with putative advantages over other minimally invasive modalities.

BACKGROUND:The purpose of this study was to assess survival for patients with malignant pleural mesothelioma (MPM), epithelial subtype, utilizing extended pleurectomy-decortication combined with intraoperative photodynamic therapy (PDT) and adjuvant pemetrexed-based chemotherapy. METHODS:From 2005 to 2013, 90 patients underwent lung-sparing surgery and PDT for MPM. All patients had a preoperative diagnosis of epithelial subtype, of which 17 proved to be of mixed histology. The remaining 73 patients with pure epithelial subtype were analyzed. All patients received lung-sparing surgery and PDT; 92% also received chemotherapy. The median follow-up was 5.3 years for living patients. RESULTS:Macroscopic complete resection was achieved in all 73 patients. Thirty-day mortality was 3% and 90-day mortality was 4%. For all 73 patients (89% American Joint Commission on Cancer stage III/IV, 69% N2 disease, median tumor volume 550 mL), the median overall and disease-free survivals were 3 years and 1.2 years, respectively. For the 19 patients without lymph node metastases (74% stage III/IV, median tumor volume 325 mL), the median overall and disease-free survivals were 7.3 years and 2.3 years, respectively. CONCLUSIONS:This is a mature dataset for MPM that demonstrates the ability to safely execute a complex treatment plan that included a surgical technique that consistently permitted achieving a macroscopic complete resection while preserving the lung. The role for lung-sparing surgery is unclear but this series demonstrates that it is an option, even for advanced cases. The overall survival of 7.3 years for the node negative subset of patients, still of advanced stage, is encouraging. Of particular interest is the overall survival being approximately triple the disease-free survival, perhaps PDT related. The impact of PDT is unclear, but it is hoped that it will be established by an ongoing randomized trial.