Faculty Bibliography

In cryoimmunotherapy, target tumors are treated with cryoablation to generate antitumor immune responses. Because immune checkpoint inhibitors have demonstrated that lung cancer can be an immunotherapy-responsive disease, there has been renewed interest in the immunological aspects of cryoablation of lung cancer. Herein, we review preclinical and clinical trials of cryoablation of primary lung tumors. We examine the magnitude of cryoablation-induced antitumor immune responses and the synergy between cryoablation and either other immunotherapies or molecular targeted therapies to improve treatment responses in advanced lung cancer. We further discuss a rationale for the addition of cryoablation to immune checkpoint inhibitors for the treatment of advanced lung cancer, which is currently under clinical investigation.

Purpose The American Society for Radiation Oncology (ASTRO) produced an evidence-based guideline on treatment with stereotactic body radiotherapy (SBRT) for patients with early-stage non-small-cell lung cancer. ASCO has a policy and set of procedures for endorsing and/or adapting clinical practice guidelines that have been developed by other professional organizations. Methods The ASTRO Evidence-Based Guideline for Stereotactic Body Radiotherapy for Early-Stage Non-Small-Cell Lung Cancer was reviewed for developmental rigor by methodologists. An ASCO Expert Panel updated the literature search and reviewed the guideline content and recommendations. Results The ASCO Expert Panel determined that the recommendations from the ASTRO guideline, published in 2017, are clear, thorough, and based on the most relevant scientific evidence. ASCO statements and minor modifications were added to enhance the applicability of the ASTRO guideline for the broader ASCO audience. Recommendations For standard operative risk patients with stage I NSCLC, SBRT is not recommended outside of a clinical trial. Lobectomy with systematic lymph node evaluation remains the recommended treatment, although a sublobar resection may be considered in select clinical scenarios. Recommendations are provided regarding the use of SBRT in high operative risk patients and for inoperative patients, including in challenging scenarios where tumors are: centrally located, > 5 cm in diameter, lacking tissue diagnosis, synchronous primary or multifocal, second primary after pneumonectomy, proximal to or involved with mediastinal structures, abutting the chest wall, or recurring after previous treatment. Qualifying statements are included to provide further guidance for implementation, and the importance of a discussion of treatment options among members of the multidisciplinary cancer care team is emphasized. Additional information is available at: www.asco.org/thoracic-cancer-guidelines and www.asco.org/guidelineswiki .

Pleural malignancies remain a serious therapeutic challenge, and are frequently refractory to standard treatment; however, they have the advantage of occurring in an enclosed cavity readily accessible for examination, biopsy, and serial sampling. Novel therapeutics can be administered via intracavitary delivery to maximize efficacy by targeting the site of involvement and potentially mitigating the adverse effects of systemic therapies. The easy accessibility of the pleural space lends itself well to repeated sampling and analysis to determine efficacy and toxicity of a given treatment paradigm. These factors support the rationale for delivery of novel therapeutics directly into the pleural space.

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: 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)

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

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.