Lung cancer is the leading cause of cancer mortality and non-small cell lung cancer (NSCLC) accounts for more than 85% of all lung cancers. Platinum-based doublet chemotherapy is the standard ...first-line treatment for metastatic NSCLC when genomic testing reveals no targetable alteration such as epidermal growth factor receptor (EGFR) mutations, anaplastic lymphoma kinase (ALK) or ROS1 translocation/re-arrangements. But, chemotherapy produces response rates ranging only between 15–30%. For patients whose disease progresses on first-line chemotherapy, second-line therapy historically consists of taxane-based salvage chemotherapy with a response rate of less than 25%. Recently, immunotherapy with checkpoint inhibitor agents have demonstrated responses in advanced NSCLC, with some patients exhibiting durable responses after discontinuing therapy. In 2015, two immune checkpoint inhibitors targeting programmed cell death-1 (PD-1), nivolumab and pembrolizumab were approved for second-line therapy of NSCLC. In 2016, another checkpoint inhibitor targeting program death-ligand 1 (PD-L1), atezolizumab was approved for the same indication. Moreover, pembrolizumab also received approval in 2016 for first-line NSCLC treatment in patients with high PD-L1 expressing tumors. Immunotherapy for NSCLC has therefore, recently evolved into a true treatment modality with the acceptance of PD-1 and PD-L1 inhibitors as the new standard of care for second-line treatment. However, it is still at the discretion of the treating physician whether to use PD-1 or PD-L1 inhibitor as data to compare these two pathways is lacking. Focus is now also on exploring their role in the adjuvant and consolidation settings for NSCLC as well as on exploring novel combinations combining these agents with chemotherapy or radiation. Research is also needed in the development of predictive and prognostic biomarkers for these agents. While vaccine therapy trials in NSCLC have so far failed to show significant clinical benefit, the demonstration of enhanced immune response in these trials suggest the vaccine therapy needs additional evaluation in combination with other therapeutic modalities especially checkpoint inhibition.
Radiation dose escalation has been shown to improve local control and survival in patients with non-small cell lung cancer in some studies, but randomized data have not supported this premise, ...possibly owing to adverse effects. Because of the physical characteristics of the Bragg peak, proton therapy (PT) delivers minimal exit dose distal to the target volume, resulting in better sparing of normal tissues in comparison to photon-based radiation therapy. This is particularly important for lung cancer given the proximity of the lung, heart, esophagus, major airways, large blood vessels, and spinal cord. However, PT is associated with more uncertainty because of the finite range of the proton beam and motion for thoracic cancers. PT is more costly than traditional photon therapy but may reduce side effects and toxicity-related hospitalization, which has its own associated cost. The cost of PT is decreasing over time because of reduced prices for the building, machine, maintenance, and overhead, as well as newer, shorter treatment programs. PT is improving rapidly as more research is performed particularly with the implementation of 4-dimensional computed tomography-based motion management and intensity modulated PT. Given these controversies, there is much debate in the oncology community about which patients with lung cancer benefit significantly from PT. The Particle Therapy Co-operative Group (PTCOG) Thoracic Subcommittee task group intends to address the issues of PT indications, advantages and limitations, cost-effectiveness, technology improvement, clinical trials, and future research directions. This consensus report can be used to guide clinical practice and indications for PT, insurance approval, and clinical or translational research directions.
Journal of Clinical Oncology
Concurrent chemoradiotherapy remains central to the treatment of limited-stage small-cell lung cancer (SCLC). SCLC is one of the few tumors treated with twice-daily ...radiotherapy (RT) in the primary definitive setting, a regimen that was established when Intergroup 0096 demonstrated its superiority over once-daily RT. However, questions remained about the optimal chemoradiotherapy regimen given the low RT dose used in the once-daily RT arm of Intergroup 0096. CALGB 30610/RTOG 0538 and CONVERT attempted to establish whether dose-escalated once-daily RT was superior to twice-daily RT in limited-stage SCLC. Although both studies showed similar survival between treatment regimens, once-daily RT was not found to be superior to twice-daily RT, and trial design limited the ability to conclude dose-escalated once-daily RT as noninferior to twice-daily RT. Thus, twice-daily RT with concurrent chemotherapy remains a standard of care in limited-stage SCLC.
To assess the efficacy and safety of stereotactic body radiation therapy (SBRT) for oligometastatic gynecologic malignancies.
A comprehensive search of the PubMed, Medline, and EMBASE databases was ...conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. “Oligometastatic” was defined as a limited number of uncontrolled/untreated metastatic lesions (typically ≤ 5), including regional nodal metastases. Primary outcomes were response rate (complete response or partial response), local control of oligometastatic lesions, and toxicity.
Of 716 screened records, 17 studies (13 full length articles, 4 conference abstracts) were selected and analyzed as 16 unique studies. A total of 667 patients were treated with ~1071 metastatic lesions identified. Primary sites included ovarian (57.6%), cervical (27.1%), uterine (11.1%), vaginal (0.4%), vulvar (0.3%), and other/unspecified (3.4%). Most patients (65.4%) presented with a single metastatic lesion. Metastatic lesion sites included the abdomen (44.2%), pelvis (18.8%), thorax (15.5%), neck (4.6%), central nervous system (4.3%), bone (1.6%), and other/unspecified (11%). Of the lesions, 64% were nodal. Response rate (among 8 studies) ranged from 49% to 97%, with 7/8 studies reporting > 75% response rate. Local control ranged from 71% to 100%, with 14/16 studies reporting ≥ 80% local control. No grade ≥ 3 toxicities were observed in 9/16 (56%) studies. Median progression-free survival (PFS) (among 10 studies) ranged from 3.3 months to 21.7 months. Disease progression most commonly occurred outside of the SBRT radiation field (79% to 100% of failures).
SBRT for oligometastatic gynecologic malignancies is associated with favorable response and local control rates but a high rate of out-of-field progression and heterogeneous PFS. Additional study into rational combinations of SBRT and systemic therapy appears warranted to further improve patient outcomes.
•SBRT for oligometastatic gynecologic malignancies is associated with favorable local control and toxicity•Local control of oligometastatic lesions ranged from 71% to 100%•No grade ≥ 3 toxicities were observed in 56% of studies•Out-of-field progression was relatively common, highlighting the opportunity for radioimmunotherapy combinations
Several sentinel phase III randomized trials have recently been published challenging traditional radiation therapy (RT) practices for small cell lung cancer (SCLC). This American Society for ...Radiation Oncology guideline reviews the evidence for thoracic RT and prophylactic cranial irradiation (PCI) for both limited-stage (LS) and extensive-stage (ES) SCLC.
The American Society for Radiation Oncology convened a task force to address 4 key questions focused on indications, dose fractionation, techniques and timing of thoracic RT for LS-SCLC, the role of stereotactic body radiation therapy (SBRT) compared with conventional RT in stage I or II node negative SCLC, PCI for LS-SCLC and ES-SCLC, and thoracic consolidation for ES-SCLC. Recommendations were based on a systematic literature review and created using a consensus-building methodology and system for grading evidence quality and recommendation strength.
The task force strongly recommends definitive thoracic RT administered once or twice daily early in the course of treatment for LS-SCLC. Adjuvant RT is conditionally recommended in surgically resected patients with positive margins or nodal metastases. Involved field RT delivered using conformal advanced treatment modalities to postchemotherapy volumes is also strongly recommended. For patients with stage I or II node negative disease, SBRT or conventional fractionation is strongly recommended, and chemotherapy should be delivered before or after SBRT. In LS-SCLC, PCI is strongly recommended for stage II or III patients who responded to chemoradiation, conditionally not recommended for stage I patients, and should be a shared decision for patients at higher risk of neurocognitive toxicities. In ES-SCLC, radiation oncologist consultation for consideration of PCI versus magnetic resonance surveillance is strongly recommended. Lastly, the use of thoracic RT is strongly recommended in select patients with ES-SCLC after chemotherapy treatment, including a conditional recommendation in those responding to chemotherapy and immunotherapy.
RT plays a vital role in both LS-SCLC and ES-SCLC. These guidelines inform best clinical practices for local therapy in SCLC.
Current guidelines for esophageal cancer contouring are derived from traditional 2-dimensional fields based on bony landmarks, and they do not provide sufficient anatomic detail to ensure consistent ...contouring for more conformal radiation therapy techniques such as intensity modulated radiation therapy (IMRT). Therefore, we convened an expert panel with the specific aim to derive contouring guidelines and generate an atlas for the clinical target volume (CTV) in esophageal or gastroesophageal junction (GEJ) cancer.
Eight expert academically based gastrointestinal radiation oncologists participated. Three sample cases were chosen: a GEJ cancer, a distal esophageal cancer, and a mid-upper esophageal cancer. Uniform computed tomographic (CT) simulation datasets and accompanying diagnostic positron emission tomographic/CT images were distributed to each expert, and the expert was instructed to generate gross tumor volume (GTV) and CTV contours for each case. All contours were aggregated and subjected to quantitative analysis to assess the degree of concordance between experts and to generate draft consensus contours. The panel then refined these contours to generate the contouring atlas.
The κ statistics indicated substantial agreement between panelists for each of the 3 test cases. A consensus CTV atlas was generated for the 3 test cases, each representing common anatomic presentations of esophageal cancer. The panel agreed on guidelines and principles to facilitate the generalizability of the atlas to individual cases.
This expert panel successfully reached agreement on contouring guidelines for esophageal and GEJ IMRT and generated a reference CTV atlas. This atlas will serve as a reference for IMRT contours for clinical practice and prospective trial design. Subsequent patterns of failure analyses of clinical datasets using these guidelines may require modification in the future.
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