Advanced-stage Cancer Patients Research Articles

Ovarian preservation in locally advanced cervical cancer undergoing neoadjuvant chemotherapy and radical surgery.

The aim of this study was to estimate the rate of ovarian metastases and recurrences among patients affected by locally advanced stage cancer patients (LACC), undergoing neoadjuvant chemotherapy (NACT) and radical surgery with conservation of ovaries. Retrospective evaluation of consecutive patients affected by LACC (stage IB2-IIB), treated by NACT followed by radical surgery at National Cancer Institute, Milan, Italy, between 1990-2015. Overall, 331 patients were included. Stage at presentation included stage IB2, IIA and IIB in 120 (36.3%), 63 (19%) and 148 (44.7%) patients, respectively. Main histotype was squamous cell carcinoma (N.=265, 80.1%) followed by adenocarcinoma/adenosquamous (N.=51, 15.4%), and more than half of patients had a grade 3 carcinoma. Overall, 102 (30.8%) women had at least one ovary preserved during surgery, while 229 (69.2%) had bilateral salpingo-oophorectomy. Comparing patients who had ovarian preservation with patients who had not, we observed that the two groups were comparable in terms of baseline characteristics. Survival outcomes were not influenced by ovarian preservation (disease-free [P=0.93] and overall [P=0.65] survivals). One (1%) woman had a localized ovarian recurrence. Our data suggest that ovarian preservation at the time of surgery is a safe option among women with LACC after NACT with no detrimental impact on oncologic outcome. Further prospective studies are warranted.

Opioid use in treatment to pain of advanced stage cancer patients

Giris: Opioidler ileri evre kanser hastalarinda tumorun tipinden bagimsiz olarak orta ve siddetli agrilarin tedavisinde temel tasidir. Opioidlerin dogru endikasyonlari olussa bile gerektigi kadar yaygin ve yeterli dozda kullanilmamaktadir. Ulkemizdeki opiod kullanimina isik tutmak icin, opioid kullanan kanser hastalarinda tani, opioid dozu ve yan etki profilini degerlendirmek istedik. Hastalar ve Metod: Haziran–Aralik 2014 tarihleri arasinda klinigimize yatan toplam 490 hastadan retrospektif olarak tarandi ve opioidle (fentanil) agri palyasyonu saglanan 173 ileri evre kanser hastasi calismaya dahil edildi. Opioid dozlari zayif (≤ 100 mg/gun oral morfin ve esdegeri) ve yuksek (>100 mg/gun oral morfin ve esdegeri) olarak ikiye ayrilarak demografik veriler ve yan etkilerle iliskisi incelendi. Bulgular: Toplam 173 hastanin, 115’i (%66.5) erkek ve 58’i (%33.5) kadindi ve ortalama yas 59.9±12 olarak saptandi. Hastalarin 141 (%81.5)’i metastatikken 32’si (%18.5) non-metastatik ileri evredeydi. 37 (%21.4) akciger, 34 (%19.7) mide, 22 (%12.7) meme, 17 (%9.8) lenfoma-losemi, 16 (%9.2) kolon, 16 (%9.2) prostat, 11 (%6.4) rektum, 10 (%5.8) pankreas ve 10 (%5.8) hastada ise diger kanserler mevcuttu. Yuksek doz opioid kullanimi sikligi ve tanilar (pankreas, mide, prostat, kolorektal, meme, akciger ve lenfoma; sirasiyla %50, %44.1, %37.5, 30.7, %36.4, %32.4, ve %17.6, P = 0.62) ve yan etki profili acisindan anlamli fark yoktu (P >0.05). Sonuc: Kanser turunden bagimsiz olarak, opioid kullanan uc hastanin en az birinde yuksek doz opioid ihtiyaci mevcuttur. Yuksek doz opioid kullanimi beraberinde daha yuksek oranda yan etki riskini de getirmediginden dolayi, kanser hastalarinda agri palyasyonu icin gerek goruldugunde opioid dozu etkin ve cok yuksek dozlara kadar artirilarak kullanilmalidir.

Pretreatment neutrophil-to-lymphocyte ratio is associated with outcome of advanced-stage cancer patients treated with immunotherapy: a meta-analysis.

To investigate the association between pretreatment blood neutrophil-to-lymphocyte ratio (NLR) and clinical outcomes for advanced-stage cancer patients treated with immunotherapy. We conducted a comprehensive literature search to assess the relationship between pretreatment blood NLR and overall survival (OS) or progression-free survival (PFS) in advanced-stage cancer patients treated with immunotherapy. Published data including hazard ratios (HRs) and related 95% confidence interval (CI) were extracted. Pooled estimates of treatment outcomes were calculated using RevMan 5.3.5. Twenty-seven studies with 4647 patients were included in the current study. The pooled results suggested that high pretreatment blood NLR was correlated with significant shorter OS (HR = 1.98, 95% CI 1.66-2.36, P < 0.001) and PFS (HR = 1.78, 95% CI 1.48-2.15, P < 0.001). Subgroup analysis stratified by study targets revealed that anti-VEGF/VEGFR therapy (HR = 2.04, 95% CI 1.61-2.60, P < 0.001) and immune checkpoints blockade (HR = 2.16, 95% CI 1.86-2.51, P < 0.001) were significantly associated with inferior OS while other targets (HR = 1.63, 95% CI 0.89-2.99, P = 0.120) were not associated with OS. There was no correlation between distinct NLR cutoff values and OS ([Formula: see text] = 0.218, P = 0.329) or PFS benefit ([Formula: see text] = -0.386, P = 0.140). Of note, HRs of PFS showed significant correlation with HRs of OS ([Formula: see text] = 0.656, P = 0.015). Elevated pretreatment blood NLR was a promising prognostic and predictive biomarker for advanced-stage cancer patients treated with immunotherapy.

Dynamic changes of circulating tumour DNA in surgical lung cancer patients: protocol for a prospective observational study

IntroductionCirculating tumour DNA (ctDNA) has potential applications in cancer management. Most previous studies about ctDNA focused on advanced stage cancer patients. We have completed a clinical prospective study (NCT02645318) and...

Preclinical and clinical studies on cancer-associated cachexia

Cancer cachexia is the wasting condition that is often seen in advanced stage cancer patients. This wasting is largely attributable to a systemic and progressive loss of skeletal muscle mass that greatly hinders performance of normal daily activities, resulting in reduced quality of life. Moreover, it negatively influences the prognosis of cancer patients. A general consensus in the field is that the loss of muscle mass is due both to an increase in protein degradation and a decrease in protein synthesis. Recent studies using preclinical models for studying cachexia have been useful in identifying the contribution of inflammatory cytokines (e.g. tumor necrosis factor-α and Interleukin-6), and myostatin receptors (e.g. the type IIB activin receptor) to cachexia development, and have led to several clinical trials. However, many questions remain about the molecular mechanisms thought to play a role in the development of cachexia. We conducted a literature search using search engines, such as PubMed and Google Scholar to identify publications within the cancer cachexia field. We summarized our current knowledge of: 1) the driving mechanisms of cancer cachexia, 2) the preclinical models available for studying the condition, and 3) the findings of recent clinical trials. Cancer cachexia is a complex and variable condition that currently has no standard effective therapeutic treatment. Further studies are desperately needed to better understand this condition and develop effective combination treatments for patients.

Tumor PD-L1 Expression and Clinical Outcomes in Advanced-stage Non-Small Cell Lung Cancer Patients Treated with Nivolumab or Pembrolizumab: Real-World Data in Taiwan.

Background: Immunotherapy that targets programmed death protein-1 (PD-1) provides improved treatment efficacy and survival in patients with metastatic non-small cell lung cancer (NSCLC), especially those with high tumor expression of PD-L1. However, data on this treatment are mostly from clinical trials enrolling highly selected patients. The real-world experience of anti-PD-1 treatment and the usefulness of tumor PD-L1 expression in prediction of treatment response are largely unknown.Methods: We retrospectively reviewed patients with stage IIIB/ IV NSCLC who received monotherapy with nivolumab or pembrolizumab, and evaluated response using RECIST 1.1 criteria. Factors associated with treatment response, progression free survival (PFS), and overall survival (OS) were determined.Results: Seventy-four NSCLC patients out of 116 examined patients were included, most of whom had adenocarcinoma (48/74, 64.9%) and received immunotherapy as a third-line or subsequent treatment (51/74, 68.9%). The median PFS and OS were 1.8 and 7.9 months, respectively. The objective response rate was 32%, but only 47 of 74 patients were evaluable. Through multivariate analysis, epidermal growth factor receptor (EGFR) mutation was independently associated with a poor treatment response. Good performance status (ECOG≤1) and smoking were independently associated with better PFS and OS. Data on tumor PD-L1 expression were available in 43 patients (58%); higher PD-L1 expression correlated with better treatment response and longer PFS. Severe treatment-related adverse events were uncommon.Conclusion: The efficacy and safety of anti-PD-1 medications for advanced NSCLC were comparable in real-world and clinical settings, except in those with poor ECOG scores. Prediction of treatment response from tumor PD-L1 expression seemed practical.

Anti-angiogenic Therapy-Mediated Endothelial Damage: A Driver of Breast Cancer Recurrence?

Anti-angiogenic therapy was conceived originally as a silver bullet able to maintain tumor dormancy indefinitely. By targeting new blood vessel formation, anti-angiogenic agents were expected to suppress the growth of any type of primary or metastatic tumor, independent of their subtype or genetic landscape. However, more that 20years after the first anti-angiogenic preclinical trial, the astonishing inhibition of metastatic outgrowth originally observed in mouse models never translated into clinics. Indeed, whereas anti-angiogenic agents (sometimes) prolong progression-free survival, they fail to impact overall survival, particularly in breast cancer. This observation revealed to be true in early- and advanced-stage breast cancer patients treated either in adjuvant or neo-adjuvant settings, suggesting that the effect of anti-angiogenic therapy on repressing growth of overt metastases- and also on preventing outgrowth of disseminated tumor cells and micrometastases- is limited. What are the reasons underlying this failure? And, more importantly, is there still room for improvement?

Case Study in International Cooperation: Cuba's Molecular Immunology Center and Roswell Park Cancer Institute.

In 1961, the USA severed diplomatic relations with Cuba, and in 1962 an embargo was imposed on trade and financial relations with that country. It was not until five decades later that the USA and Cuba would reestablish relations. This opened the way for the New York State Trade Mission to Cuba in April 2015, during which Cuba's Molecular Immunology Center and Buffalo, New York's Roswell Park Cancer Institute signed a formal agreement that would set in motion biotechnology research collaboration to address one of the most important causes of death in both countries. Significant research from Cuba led to this groundbreaking collaboration. The purpose of this paper is to discuss the development of this cooperation, from the Molecular Immunology Center's initial investigations, through the opening of a phase I clinical trial at Roswell Park Cancer Institute with therapies developed at the Center. This cooperation was responsible for the first clinical trial for CIMAvax-EGF involving advanced-stage non-small cell lung cancer patients in the USA. A license was also approved by the US Department of the Treasury's Office of Foreign Assets Control authorizing a commercial partnership for development of biotechnology products, combining the cancer research efforts of both institutions. This unusual collaboration between Cuba and the USA-the US economic embargo and travel restrictions not withstanding-opens good prospects for expanded medical research between the two countries. While political and logistical challenges remain, the shared mission and dedication of these Cuban and US scientists points the way towards relationships that can lead to development, testing, approval and use of promising new therapies for cancer patients. KEYWORDS Biotechnology, clinical trials, cancer vaccines, cancer immunotherapy, non-small cell lung cancer, NSCLC, Cuba, USA.

Palliative sedation (PS) given to patients treated at the Fundación Santa Fe de Bogotá.

Background. Around 50% of advanced-stage cancer patients have inadequate control of symptoms during the final period of life; palliative sedation (PS) would seem to be appropriate in such scenario.

Molecular and cellular mechanisms of chemoresistance in pancreatic cancer.

Pancreatic Ductal Adenocarcinoma (PDAC) is one of the most chemoresistant cancers, and current therapies targeting cancer-associated molecular pathways have not given satisfactory results, owing in part to rapid upregulation of alternative compensatory pathways. Most of the available treatments are palliative, focussing on improving the quality of life. At present, available options are surgery, embolization, radiation, chemotherapy, immunotherapy and use of other more targeted drugs. In this review, we describe the cellular and molecular effects of current chemotherapy drugs such as gemcitabine, FOLFIRINOX (5-fluorouracil [5-FU], oxaliplatin, irinotecan, and leucovorin) and ABRAXANE (nab-Paclitaxel), which have shown a survival benefit, although modest, for pancreatic cancer patients. Nevertheless, gemcitabine remains the standard first-line option for advanced-stage pancreatic cancer patients and, as resistance to the drug has attracted an increasing scientific interest, we deliberate on the main intracellular processes and proteins vital in acquired chemoresistance to gemcitabine. Lastly, our review examines various microenvironmental factors capable of instigating PDAC to develop resistance to chemotherapeutic drugs.

P2.07-040 Pre-Treatment Tumor Volume in Non-Small Cell Lung Cancer (NSCLC) as a Predictor of Response to PD-1 Inhibitors

PD-1 inhibitors are new anti-cancer treatments that aimed to re-instate the natural anti-cancer immune-mediated cytotoxicity. Although this new class of therapy offers hope for many advanced stage cancer patients (pts), little is known on the characteristics of pts who are likely to respond. We hypothesized that response rate (RR) and overall survival (OS) would be inversely associated with pre-treatment tumor volume (PTV), independent of other variables such as age, lymph node (LN) metastasis and liver metastasis.

583P - Serum miRNA Assays for detection and management of gastric and lung cancers

Background:Lung cancer is the most prevalent cancer and the leading cause of cancer death worldwide. Prognosis remains poor for advanced stage cancer patients. Currently, LDCT is recommended as a screening test for smokers in the U.S. However, the poor specificity (73% specificity at 94% sensitivity) of LDCT has raised significant concern for its high chance of false positive (96% of nodules are benign). Gastric cancer is the 3rd leading cause of cancer deaths worldwide. Currently, endoscopy is the only reliable method for early diagnosis. However, the invasiveness and cost limit its usage as a screening test. MicroRNAs are key regulators of cancer pathogenesis. They are exceptionally stable in body fluids, making them potential noninvasive biomarker for cancers. Methods: We aim to develop serum miRNA assays to aid screening and early detection of lung and gastric cancers. Lung cancer miRNA biomarkers were identified through a Chinese male smoker case-control cohort (n = 432) and validated in 4 additional cohorts from China, Europe, Singapore and US (n = 880). Gastric cancer miRNA biomarkers were identified through a Singaporean case-control cohort (n = 472) and validated in 3 additional cohorts from Singapore, Korea and Japan (n = 467). Multivariate miRNA biomarker panels were formulated by sequence forward floating search and support vector machine using quantitative miRNA expression data. Results: More than 600 miRNAs were profiled with MiRXES miRNA qPCR assay platform. Among which, 39 miRNAs were found significantly altered between early-stage lung cancer and matched controls. A six-miR biomarker panel could classify cancer from controls with AUC>0.93 across all cohorts. A 24-miR gastric cancer panel was optimized using discovery set (AUC=0.92) and validated in two blinded studies with fixed algorithm and threshold definition. The 24-miR panel showed 90% sensitivity and 81% specificity in the Korean cohort (AUC=0.91) and had 90% sensitivity and 75% specificity in the Singaporean Chinese cohort (AUC=0.89). Conclusions: We have developed serum miRNA panels capable of detecting early-stage lung and gastric cancers. The two miRNA assays are undergoing multi-center prospective clinical validation studies (n > 15,000) to demonstrate clinical utility. Legal entity responsible for the study: MIRXES Pte Ltd Funding: MIRXES Pte Ltd Disclosure: L. Zhou: Co-founder and shareholder of MIRXES Pte Ltd.

A Model to Predict the Use of Surgical Resection for Advanced-Stage Non-Small Cell Lung Cancer Patients

For advanced-stage non-small cell lung cancer, chemotherapy and chemoradiotherapy are the primary treatments. Although surgical intervention in these patients is associated with improved survival, the effect of selection bias is poorly defined. Our objective was to characterize selection bias and identify potential surgical candidates by constructing a Surgical Selection Score (SSS). Patients with clinical stage IIIA, IIIB, or IV non-small cell lung cancer were identified in the National Cancer Data Base from 1998 to 2012. Logistic regression was used to develop the SSS based on clinical characteristics. Estimated area under the receiver operating characteristic curve was used to assess discrimination performance of the SSS. Kaplan-Meier analysis was used to compare patients with similar SSSs. We identified 300,572 patients with stage IIIA, IIIB, or IV non-small cell lung cancer without missing data; 6% (18,701) underwent surgical intervention. The surgical cohort was 57% stage IIIA (n= 10,650), 19% stage IIIB (n= 3,483), and 24% stage IV (n= 4,568). The areas under the receiver operating characteristic curve from the best-fit logistic regression model in the training and validation sets were not significantly different, at 0.83 (95% confidence interval, 0.82 to 0.83) and 0.83 (95% confidence interval, 0.82 to 0.83). The range of SSS is 43 to 1,141. As expected, SSS was a good predictor of survival. Within each quartile of SSS, patients in the surgical group had significantly longer survival than nonsurgical patients (p < 0.001). A prediction model for selection of patients for surgical intervention was created. Once validated and prospectively tested, this model may be used to identify patients who may benefit from surgical intervention.

1702O - Clinical implications of genomic variants identified in over 30,000 advanced-stage cancer patients by next-generation sequencing of circulating tumor DNA

1702O - Clinical implications of genomic variants identified in over 30,000 advanced-stage cancer patients by next-generation sequencing of circulating tumor DNA

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Prognostic value of programmed death ligand 1, p53, and Ki-67 in patients with advanced-stage colorectal cancer

Current prognostic indicators are ineffective for identifying advanced-stage colorectal cancer (CRC) patients with high risk of recurrence after surgical resection. We investigated the prognostic value of p53, Ki-67, and programmed death ligand 1 (PD-L1) in 254 patients with stage II and III CRC. The expression of p53 was positive in 63% of cases. Up-regulation of p53 was associated with smaller tumor size (P=.001) and higher Ki-67 labeling index (LI) (P=.031). The tumor Ki-67 LI was high (≥20%) in 197 (78%) of the patients. High Ki-67 LI was associated with higher TNM stage (P=.031), positive p53 expression (P=.031), and negative PD-L1 expression (P=.003). The 5-year relapse-free survivals (RFS) were 53% and 89%, respectively, for the p53-positive and Ki-67 LI-high patients and the p53-negative and Ki-67 LI-low patients (P<.001). In univariate analysis, negative p53 (P=.001), low Ki-67 LI (P=.006), low PD-L1 expression (P=.044), low TNM stage (P<.001), rectosigmoid location (P=.026), and small size (P=.013) were significantly related to RFS. In multivariate Cox regression analysis, positive p53 expression (hazard ratio [HR]: 2.48; 95% confidence interval: 1.34-4.59, P=.004), high Ki-67 LI (HR, 2.62; 95% CI, 1.12-6.14, P=.027) and high TNM stage (HR, 2.598; 95% CI, 1.55-4.37, P<.001,) were independent predictors of unfavorable prognosis. In summary, PD-L1, Ki-67, and p53 staining individually had significant prognostic value for patients with stage II and III CRC. Moreover, combining p53 H-score ≥35 and Ki-67 LI ≥20% identifies patients with poor clinical outcome.

Body weight, hemoglobin, and absolute neutrophil count in patients with advanced-stage epithelial ovarian cancer who received chemotherapy: A single-center study

The side effects of chemotherapy, a treatment modality of ovarian cancer, can disrupt overall treatment. To date, the clinical and laboratory profiles of ovarian cancer patients during chemotherapy have not been investigated. This study aimed to elucidate the clinical and laboratory profiles of patients with advanced-stage epithelial ovarian cancer who received chemotherapy in Dr. Cipto Mangunkusumo Hospital, including body mass index (BMI), hemoglobin (Hb), and absolute neutrophil count (ANC). To generate these clinical and laboratory profiles, we collected secondary data from the medical records of advanced-stage epithelial ovarian cancer patients who received six cycles of carboplatin and paclitaxel chemotherapy. We enrolled 23 patients with advanced-stage epithelial ovarian cancer patients who received six cycles of chemotherapy. Mean patient BMI before and after chemotherapy was 22.86 kg/m2 and 21.78 kg/m2, respectively. Hb levels before chemotherapy were 8–13 g/dl, with Hb < 10 g/dl in one patient (4.35%) and Hb ≥ 10 g/dl in 22 patients (95.65%). Mean ANC was 5845.6 ± 3325.0. An average of 24.65% of patients experienced anemia after each cycle of chemotherapy. Mean ANC before chemotherapy was 3.5582 ± 3.3250. An average of 26.81% of patients had ANC <1500 after each cycle of chemotherapy; no patients had ANC <1500 before chemotherapy initiation. After six cycles of chemotherapy, three patients (13.04%) had mild neutropenia, four patients (17.39%) had moderate neutropenia, and one patient (4.35%) had severe neutropenia. Of the 22 patients with Hb ≥ 10 g/dl before chemotherapy, 16 (72.72%) experienced a decrease in ANC during chemotherapy. Of the 20 patients (60.87%) with normal BMI or higher, 14 experienced a decrease in ANC during chemotherapy. The mean patient body weight decreased after six cycles of chemotherapy. Hb and ANC were persistently decreased in approximately a quarter of the 23 subjects. The decrease in ANC was not influenced by initial Hb and BMI.

Management of peritoneal metastasis of gastric cancer

Peritoneal metastases (PM) from disseminations of gastric cancer, presented as a recurrence, its considered fatal with no definitive cure. newer agents like S1 and docetaxel have shown some advantage but nevertheless the median overall survival with the current first line chemotherapy is only 8 to 14 months which shows no great improvement when adding targeted therapy. A multidisciplinary approach combining cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has been developed. European and Far East studies reported long-term survival benefits in case of complete cytoreduction with 5-year survival rates up to 25%. In order to prevent peritoneal recurrence and to improve overall survival, adjuvant HIPEC is the most evidence-based indication for advanced-stage gastric cancer patients without PM. The rationale for immunotherapy is solid, with ongoing studies combining CRS and intraperitoneal immunotherapeutic agent. The detection of peritoneal cancer cells is the most reasonable way for identifying the metastasis risk after operation. Peritoneal washing appears to be a sensitive method. Thus, the prevention of peritoneal recurrence mandates the use of multiple modalities and locoregional treatments strategy.

Communication about uncertainty and hope: A randomized controlled trial assessing the efficacy of a communication skills training program for physicians caring for cancer patients

BackgroundAlthough previous studies have reported the efficacy of communication skills training (CST) programs, specific training addressing communication about uncertainty and hope in oncology has not yet been studied. This paper describes the study protocol of a randomized controlled trial assessing the efficacy of a CST program aimed at improving physician ability to communicate about uncertainty and hope in encounters with cancer patients.Methods/designPhysician participants will be randomly assigned in groups (n = 3/group) to a 30-h CST program (experimental group) or to a waiting list (control group). The training program will include learner-centered, skills-focused, practice-oriented techniques. Training efficacy is assessed in the context of an encounter with a simulated advanced stage cancer patient at baseline and after the CST for the experimental group, and after four months for the waiting-list group. Efficacy assessments will include communicational, psychological and physiological measures. Group-by-time effects will be analyzed using a generalized estimating equation (GEE). A power analysis indicated that a sample size of 60 (30 experimental and 30 control) participants will be sufficient to detect effects.DiscussionThe current study will aid in the development of effective CST programs to improve physician ability to communicate about uncertainty and hope in encounters with cancer patients.Trial registrationUS Clinical Trials Register NCT02836197.

Abstract CT125: A prospective study of dynamic changes of circulating tumor DNA in surgical lung cancer patients

Abstract Objective: Most previous studies about circulating tumor DNA focused on advanced stage cancer patients. We have completed a clinical prospective study (NCT02645318) and showed the feasibility of ctDNA detection in early stage (I-IIA) non-small cell lung cancer (NSCLC) patients, which have been published (Sci. Rep.6,31985,2016). We also investigated its clinical application on early diagnosis and showed our data by oral presentation in American Association of Thoracic Surgery Annual meeting 2016 in Baltimore. Based on our previous study, we further evaluated the clinical value of ctDNA. Few study revealed dynamic changes of circulating tumor DNA in surgical lung cancer patients that no criterion has been established of how to use it for surveillance. The aim of this study is to investigate the elimination rate of circulating tumor DNA level after surgery. This is the first prospective study to evaluate the dynamic changes of ctDNA in surgical lung cancer patients. Method: Consecutive patients with suspected lung cancer who underwent curative-intent lung resection were enrolled prospectively in this study from 11/2016. 10 mL blood samples were taken by intravenous puncture. Plasma samples were obtained before surgery (time A) and at a series of scheduled time-points (2 min to 72 hours, time B to F) after tumor resection. DNA was prepared from 4mL of purified plasma. We designed a multiplex assay based on circulating single-molecule amplification and resequencing technology (cSMART) to simultaneously detect and quantitate hot spot EGFR, KRAS, BRAF, ERBB2, PIK3CA, TP53, ALK, RET and MET plasma DNA variants, with matched white blood cell DNA as controls. Positive plasma mutations were validated in tumor tissue by targeted sequencing. Study protocol (ClinicalTrials.gov identifier NCT02965391) was approved by the Peking University People’s Hospital Medical Ethics Committee (2016PHB156-01). Results: A hundred and seven patients were enrolled, in which 18(16.8%)patients showed detectable driver mutations in the preoperative plasma sample (time A), 9 patients were excluded due to non-radical surgery(3); no plasma of other time-points(2); non-somatic driver mutations (2); no surgery performed(2). Therefore, 9 patients (4 stage I, 3 stage II and 2 stage III) with 11 mutations met the inclusion criteria, which included four EGFR, three TP53, two PIK3CA, one KRAS and one ALK mutations. All of the patients had a decrease of mutation ratio as time went on and dropped to 0 after 72 hours of tumor resection. The average mutation ratio was 2.99%, 1.64%, 0.82%, 0.03%, 0.015% and 0 at the time-points A to F, respectively. The evaluated half-life of ctDNA was about 10 min. The total DNA template appeared higher post-operation than pre-operation (3082±2234 vs.1787±1181, p=0.12).One patient had concurrent driver mutations of PIK3CA E545K and EGFR L858R. PIK3CA was detected in time A and decreased gradually from time B to C. EGFR was not detected in time A but in plasma time B and decreased in time C. Conclusion: The elimination of ctDNA in lung cancer patients is very rapid after surgical resection. The intraoperative manipulation may not only push forward releasing of cell free DNA, but also lead heterogeneous tumor mutation discharging to plasma. Detection of ctDNA 72h after surgery could be the reference value for postoperative surveillance. Note: This abstract was not presented at the meeting. Citation Format: Kezhong Chen, Fan Yang, Heng Zhao, Tianyang Wang, Lien Tu Wang, Jun Wang. A prospective study of dynamic changes of circulating tumor DNA in surgical lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT125. doi:10.1158/1538-7445.AM2017-CT125