New Methods Of Clinical Response Evaluation In Solid Tumours: Exploratory Studies

Response evaluation was a very important part of clinical oncology practice.Response evaluation criteria in solid tumours(RECIST)was the primary tool over the years.However,RECIST was originally be developed for evaluating the activity and efficacy of new cancer therapeutics in solid tumors.RECIST guideline has made it clear that the evaluation of tumor response in the daily clinical practice of oncology may not be performed according to predefined criteria,and it was not intended that these RECIST guidelines play a role in that decision making,excepted if determined appropriate by the treating oncologist[1-2].So we considered that it would helpful to oncologist if some new methods be developed to improve response evaluation in daily oncology practice.This study consisted three parts to discuss new methods of clinical response evaluation by analyzed clinical data of advanced cancer patients in oncology department of General Hospital of Shenyang military command.Part One Variability in assessing solid tumour treatment response: target pulmonary lesions of NSCLC as a paradigmObjective: Target lesions measurement was the basis for response evaluation in solid tumours,so it necessary to know the observer variability in the current clinical practice.Materials and methods: A subset of seventy-eight pulmonary lesions from NSCLC patients’ chest images were pre-selected from Jan 1,2014 to Jun 30,2014 in clinical database of oncology department of General Hospital of Shenyang military command.Two radiologists with above 10 years experiences measured the target lesions independently at PACS workstation.Repeat measurement was performed four weeks later by one of the radiologists.Bland-Altman methods were used to assess intra-and interobserver variability.Intraclass correlation coefficients were used to assess intra-and interobserver agreement.Result:Bland-Altman methods showed that intra-and interobserver variability were similar to RECIST cut-off values in the whole group.Intra-and interobserver variability were between ±10% with an absolutely change at least 3 mm after excluding the lesions with obvious different measuring lines.The intraclass correlation coefficients for intraand interobserver agreement rates were between 0.9 and 1 whether lung window or soft tissue window.Conclusion: A relatively low variability was detected in assessing target pulmonary lesions of NSCLC.It would be helpful for oncologists to assess the tumour response or progress more sensitivity.Part Two A prospective observational study of relationship between depth of response of target lesions and survival: extensive stage SCLC first-line therapy patients as a paradigmObjective: Prolongation of survival was one of the mainly goals of treatment for advanced cancer,however,whether tumor response to chemotherapy could prolong survival was still controversial.This study was to assess the relationship between depth of response and survival,extensive stage SCLC first-line therapy patients as a paradigm.Materials and methods: 51 patients with extensive stage SCLC who received first-line chemotherapy in the Oncology Department of the General Hospital of Shenyang Military Command from Sep 1,2014 to Feb 29,2016 were included in the prospective observational analysis.Spearman rank correlation and linear regression was used to evaluate the relationship between depth of response with PFS and OS.Log-rank test was used for univariate analysis,and COX proportional regression model was used for multivariate analysis.Result: Spearman rank correlation analysis and linear regression analysis showed that depth of response was moderately correlated with PFS and OS.According to the results of multivariate analysis,depth of response≥10%、weight loss<5%、ECOG PS 0-1、chemotherapy cycles≥4 were independent prognostic factors for PFS of extensive stage SCLC,and weight loss<5%、ECOG PS 0-1、chemotherapy cycles≥4 and second line chemotherapy were independent prognostic factors for OS of extensive stage SCLC.However,depth of response was no statistical correlation with OS.Conclusion: Depth of response≥10% was a prognostic factor for PFS,but not OS,in patients with extensive stage SCLC first-line therapy patients.Part Three Exploratory research of decision-making role of serum tumor marker for response evaluation: serum CEA and CA153 in patients with advanced breast cancer as a paradigmObjective: Past study showed that serum tumor marker could predict the efficacy of chemotherapy,but it was not recommended to evaluate the efficacy of serum tumor markers alone in RECIST.This study evaluates whether serum tumor marker could be a decision-making factor for response evaluation by analyzed the relationship between CEA and CA153 with tumor imaging change in patients with advanced breast cancer.Materials and methods: Medical records of 93 patients with advanced breast cancer who received chemotherapy in the Oncology Department of the General Hospital of Shenyang Military Command from Jan 1,2011 to Feb 31,2015 were included in the retrospective analysis.105 CEA cases and 139 CA153 cases were collected from a total of 188 times response evaluations.Predictive validity of serum CEA and CA153 was assessed for diagnosing no-imaging progression.Results: CEA was continuously reduced by 10%,with sensitivity of 54.1% and specificity of 95%.CA153 was continuously reduced by 40%,with sensitivity of 19.1% and specificity of 96.6%.Conclusion: Serum CEA and CA153 could be considered as decision-making role for response evaluation when they are continuously reduced by at least 10% and 40%,respectively.In conclusion,it shouldn’t rigidly adhere to RECIST to evaluate response in clinical practice.We should determine the real change of tumor size in combination with the specific situation,which was helpful to adjust regimen in time;we should realize the significance of depth of response to prolongation of survival according to specific clinical factors,which was helpful to understand the clinical value of tumor response;and we maybe could regard serum tumor marker as decision-making factor in some appropriate situation,which was helpful to save the medical resources and time.