Objective response rate assessment in oncology: Current situation and future expectations

The tumor objective response rate(ORR)is an important parameter to demonstrate the efficacy of a treatment in oncology.The ORR is valuable for clinical decision making in routine practice and a significant end-point for reporting the results of clinical trials.World Health Organization and Response Evaluation Criteria in Solid Tumors(RECIST)are anatomic response criteria developed mainly for cytotoxic chemotherapy.These criteria are based on the visual assessment of tumor size in morphological images provided by computed tomography(CT)or magnetic resonance imaging.Anatomic response criteria may not be optimal for biologic agents,some disease sites,and some regional therapies.Consequently,modifications of RECIST,Choi criteria and Morphologic response criteria were developed based on the concept of the evaluation of viable tumors.Despite its limitations,RECIST v1.1 is validated in prospective studies,is widely accepted by regulatory agencies and has recently shown good performance for targeted cancer agents.Finally,some alternatives of RECIST were developed as immune-specific response criteria for checkpoint inhibitors.Immune RECIST criteria are based essentially on defining true progressive disease after a confirmatory imaging.Some graphical methods may be useful to show longitudinal change in the tumor burden over time.Tumor tissue is a tridimensional heterogenous mass,and tumor shrinkage is not always symmetrical;thus,metabolic response assessments using positron emission tomography(PET)or PET/CT may reflect the viability of cancer cells or functional changes evolving after anticancer treatments.The metabolic response can show the benefit of a treatment earlier than anatomic shrinkage,possibly preventing delays in drug approval.Computer-assisted automated volumetric assessments,quantitative multimodality imaging in radiology,new tracers in nuclear medicine and finally artificial intelligence have great potential in future evaluations.

Common toxicities and objective response rate in metastatic colorectal cancer patients treated with irinotecan based regimens

Objective： The aim of our study was to investigate if common toxicities are correlated to objective response rate （ORR） in metastatic colorectal cancer （mCRC） patients treated by irinotecan based regimens. Methods： Univadate and multivariate logistic regression analyses were performed to evaluate correlations between common toxicities and binary ORR in 106 mCRC patients from a prospective cohort treated with irinotecan based regimens. Results： The most frequent severe toxicities （Grade 3/4） were as follows： neutropenia （27.4%）, diarrhea （16.9%）, leucopenia （12.6%）, vomiting （3.2%） and thrombocytopenia （2.1%）. Thrombocytosis was observed in 25 （26.3%） patients. ORR was 25.3%. Thrombocytopenia （P = 0.014）, line of chemotherapy （P = 0.028） and thrembocytosis （P = 0.033） were correlated with ORR in univariate analysis. In multivariate analysis, thrombocytopenia （odds ratio [OR] = 8.600, 95% confidence interval [CI] = 1.705-43.385, P = 0.009） and first line chemotherapy （OR = 5.155, 95% CI = 1.153-23.256, P = 0.032） positively related to ORR. Conclusion： Threm- bocytopenia may be an indicator of ORR in mCRC patients treated by irinotecan plus 5-fluorouracil/capecitabine. Evidence is not strong enough to prove that irinotecan based regimens-induced diarrhea, leucopenia, neutropenia or vomiting is associ- ated with ORR.

Nab-paclitaxel plus capecitabine as first-line treatment for advanced biliary tract cancers:An open-label,non-randomized,phase II clinical trial

BACKGROUND Biliary tract cancers(BTCs)are a heterogeneous group of tumors with high malignancy,poor prognosis,and limited treatment options.AIM To explore the efficacy and safety of nab-paclitaxel plus capecitabine as first-line treatment for advanced and metastatic BTCs.METHODS This open-label,non-randomized,double-center,phase II clinical trial recruited systemic therapy-naive patients with unresectable or metastatic BTCs between April 2019 and June 2022 at Beijing Cancer Hospital and the First Hospital of China Medical University.Eligible patients were administered nab-paclitaxel(150 mg/m^(2),day 1)and capecitabine(2000 mg/m^(2),twice daily,days 1-7)in 14-day cycles until experiencing intolerable toxicity or disease progression.The primary outcome was the objective response rate(ORR).The secondary outcomes included the disease control rate(DCR),overall survival(OS),progression-free survival(PFS),and safety.RESULTS A total of 44 patients successfully completed the trial,with a median age of 64.00 years(interquartile range,35.00-76.00),and 26(59.09%)were females.Tumor response assessment was impeded for one patient due to premature demise from tumor hemorrhage.Among the remaining 43 patients undergoing at least one imaging assessment,the ORR was 23.26%[95%confidence interval(CI):11.80%-38.60%],and the DCR was 69.77%(95%CI:53.90%-82.80%).The median OS was 14.1 months(95%CI:8.3-19.9),and the median PFS was 4.4 months(95%CI:2.5-6.3).A total of 41 patients(93.18%)experienced at least one adverse event(AE),with 10 patients(22.73%)encountering grade≥3 AEs,and the most frequent AEs of any grade were alopecia(79.50%),leukopenia(54.55%),neutropenia(52.27%),and liver dysfunction(40.91%),and no treatment-related deaths were documented.CONCLUSION Nab-paclitaxel plus capecitabine may be an effective and safe first-line treatment strategy for patients with advanced or metastatic BTCs.

Effectiveness and tolerability of programmed cell death protein-1 inhibitor+chemotherapy compared to chemotherapy for upper gastrointestinal tract cancers

BACKGROUND The combination of programmed cell death protein-1(PD-1)inhibitor and che-motherapy is approved as a standard first-or second-line treatment in patients with advanced oesophageal or gastric cancer.However,it is unclear whether this combination is superior to chemotherapy alone.AIM To assess the comparative effectiveness and tolerability of combining PD-1 inhibitors with chemotherapy vs chemotherapy alone in patients with advanced gastric cancer,gastroesophageal junction(GEJ)cancer,or oesophageal carcinoma.METHODS We searched the PubMed and Embase databases for studies that compared the efficacy and tolerance of PD-1 inhibitors in combination with chemotherapy vs chemotherapy alone in patients with advanced oesophageal or gastric cancer.We employed either random or fixed models to analyze the outcomes of each clinical trial,en-compassing data on overall survival(OS),progression-free survival(PFS),objective response rate,and adverse events(AEs).RESULTS Nine phase 3 clinical trials(7016 advanced oesophageal and gastric cancer patients)met the inclusion criteria.Our meta-analysis demonstrated that the pooled PD-1 inhibitor+chemotherapy group had a significantly longer OS than the chemotherapy-alone group[hazard ratio(HR)=0.76,95%confidence interval(CI):0.71-0.81];the pooled PFS result was consistent with that of OS(HR=0.67,95%CI:0.61-0.74).The count of patients achieving an objective response in the PD-1 inhibitor+chemotherapy group surpassed that of the chemotherapy-alone group[odds ratio(OR)=1.86,95%CI:1.59-2.18].AE incidence was also higher in the combination-therapy group than in the chemotherapy-alone group,regardless of whether≥grade 3 only(OR=1.30,95%CI:1.07-1.57)or all AE grades(OR=1.88,95%CI:1.39-2.54)were examined.We performed a subgroup analysis based on the programmed death-ligand 1(PD-L1)combined positive score(CPS)and noted extended OS and PFS durations within the CPS≥1,CPS≥5,and CPS≥10 subgroups of the PD-1 inhibitor+chemotherapy group.CONCLUSION In contrast to chemotherapy alone,the combination of PD-1 inhibitor and chemotherapy appears to present a more favorable option for initial or subsequent treatment in patients with gastric cancer,GEJ tumor,or oesophageal cancer.This holds true particularly for individuals with PD-L1 CPS scores of≥5 and≥10.

Evaluation of oxaliplatin and tigio combination therapy in locally advanced gastric cancer

BACKGROUND Locally advanced gastric cancer(LAGC)is a common malignant tumor.In recent years,neoadjuvant chemotherapy has gradually become popular for the treatment of LAGC.AIM To investigate the efficacy of oxaliplatin combined with a tigio neoadjuvant chemotherapy regimen vs a conventional chemotherapy regimen for LAGC.METHODS Ninety patients with LAGC were selected and randomly divided into control and study groups with 45 patients in each group,according to the numerical table method.The control group was treated with conventional chemotherapy,and the study group was treated with oxaliplatin combined with tigio-neoadjuvant che-motherapy.The primary outcome measures were the clinical objective response rate(ORR)and surgical resection rate(SRR),whereas the secondary outcome measures were safety and Karnofsky Performance Status score.RESULTS The ORR in the study group was 80.00%,which was significantly higher than that of the control group(57.78%).In the study group,SRR was 75.56%,which was significantly higher than that of the control group(57.78%).There were 15.56%adverse reactions in the study group and 35.56%in the control group.These differences were statistically significant between the two groups.CONCLUSION The combination of oxaliplatin and tigio before surgery as neoadjuvant chemotherapy for patients with LAGC can effectively improve the ORR and SRR and is safe.

Clinical values of Barcelona Clinic Liver Cancer subgroup and up-to-7 criteria in intermediate stage hepatocellular carcinoma with transcatheter arterial chemoembolization

BACKGROUND Transarterial chemoembolization(TACE)is a recommended treatment for patients with intermediate stage hepatocellular carcinoma(HCC)but with variable treatment outcomes.AIM To determine factors for predicting outcomes of TACE in patients with intermediate stage B HCC.METHODS Patients with Barcelona Clinic Liver Cancer(BCLC)stage B HCC who underwent TACE as the primary treatment were enrolled at Taichung Veterans General Hospital from January 2005 to December 2009.Patients were assigned to either the objective responder(OR)group or the non-OR group according to mRECIST criteria.Clinical and radiological characteristics were compared between the 2 groups.The overall survival of enrolled subjects was analyzed.RESULTS In 128 enrolled patients,66(51.6%)were in the OR group and 62(48.4%)in the non-OR group.Compared with the non-OR group,the OR group had a significantly smaller HCC size(6.55 cm vs 9.50 cm,P=0.001)and was within the up-to-7 criteria(50%vs 26.7%,P=0.001).After multivariable analyses,these significant associations still existed.Overall survival rate of all the subjects averaged 20.65±13.26 mo.The survival rate at 1-year was 64.8%,2-year was 46.9%,and 3-year was 31.2%.For those patients with OR to TACE,smaller tumor size and within up-to-7 criteria were associated with significantly better overall survival.Those patients with subgroup B1 had the highest OR ratio(75%)and better overall survival(26.70±12.07 mo)after TACE.CONCLUSION BCLC stage B HCC patients with smaller tumor size or within up-to-7 criteria had better survival outcomes to TACE.BCLC stage B subgroup is useful to predict refractoriness to TACE.

Intracranial activity of first-line immune checkpoint inhibitors combined with chemotherapy in advanced non-small cell lung cancer

Background:Immune checkpoint inhibitors(ICIs)are increasingly used as first-line therapy for patients with advanced non-small cell lung cancer(NSCLC)harboring no actionable mutations;however,data on their efficacy among patients presenting with intracranial lesions are limited.This study aimed to explore the efficacy and safety of ICIs combined with chemotherapy in advanced NSCLC patients with measurable brain metastasis at initial diagnosis.Methods:Our study retrospectively analyzed clinical data of a total of 211 patients diagnosed with driver gene mutation-negative advanced NSCLC with measurable,asymptomatic brain metastasis at baseline from Hunan Cancer Hospital between January 1,2019 and September 30,2021.The patients were stratified into two groups according to the first-line treatment regimen received:ICI combined with chemotherapy(n=102)or chemotherapy(n=109).Systemic and intracranial objective response rates(ORRs)and progression-free survival(PFS)were analyzed.Adverse events were also compared between the groups.Results:Compared with the chemotherapy-based regimen,the ICI-containing regimen was associated with a significantly higher intracranial(44.1%[45/102]vs.28.4%[31/109],χ^(2)=5.620,P=0.013)and systemic(49.0%[50/102]vs.33.9%[37/109],χ^(2)=4.942,P=0.019)ORRs and longer intracranial(11.0 months vs.7.0 months,P<0.001)and systemic(9.0 months vs.5.0 months,P<0.001)PFS.Multivariable analysis consistently revealed an independent association between receiving ICI plus platinum-based chemotherapy as a first-line regimen and prolonged intracranial PFS(hazard ratio[HR]=0.52,95%confidence interval[CI]:0.37-0.73,P<0.001)and systemic PFS(HR=0.48,95%CI:0.35-0.66,P<0.001).No unexpected serious adverse effects were observed.Conclusion:Our study provides real-world clinical evidence that ICI combined with chemotherapy is a promising first-line treatment option for driver gene mutation-negative advanced NSCLC patients who present with brain metastasis at initial diagnosis.Clinical trial registration:https://www.clinicaltrials.gov/,OMESIA,NCT05129202.

Phase II clinical trial using camrelizumab combined with apatinib and chemotherapy as the first-line treatment of advanced esophageal squamous cell carcinoma

Background:Effective therapeutic options are limited for patients with advanced esophageal squamous cell carcinoma(ESCC).The incorporation of an immune checkpoint inhibitor and a molecular anti-angiogenic agent into the commonly adopted chemotherapy may produce synergistic effects.Therefore,we aimed to investigate the efficacy and safety of camrelizumab plus apatinib combined with chemotherapy as the first-line treatment of advanced ESCC.Methods:In this single-arm prospective phase II trial,patients with unresectable locally advanced or recurrent/metastatic ESCC received camrelizumab 200 mg,liposomal paclitaxel 150 mg/m2,and nedaplatin 50 mg/m2 on day 1,and apatinib 250 mg on days 1-14.The treatments were repeated every 14 days for up to 9 cycles,followed by maintenance therapy with camrelizumab and apatinib.The primary endpoint was objective response rate(ORR)according to the Response Evaluation Criteria in Solid Tumors(version 1.1).Secondary endpoints included disease control rate(DCR),progression-free survival(PFS),overall survival(OS),and safety.Results:We enrolled 30 patients between August 7,2018 and February 23,2019.The median follow-up was 24.98 months(95%confidence interval[CI]:23.05-26.16 months).The centrally assessed ORR was 80.0%(95%CI:61.4%-92.3%),with a median duration of response of 9.77 months(range:1.54 to 24.82+months).The DCR reached 96.7%(95%CI:82.8%-99.9%).The median PFS was 6.85 months(95%CI:4.46-14.20 months),and the median OS was 19.43 months(95%CI:9.93 months–not reached).The most common grade 3-4 treatmentrelated adverse events(AEs)were leukopenia(83.3%),neutropenia(60.0%),and increased aspartate aminotransferase level(26.7%).Treatment-related serious AEs included febrile neutropenia,leukopenia,and anorexia in one patient(3.3%),and single cases of increased blood bilirubin level(3.3%)and toxic epidermal necrolysis(3.3%).No treatment-related deaths occurred.Conclusions:Camrelizumab plus apatinib combined with liposomal paclitaxel and nedaplatin as first-line treatment demonstrated feasible anti-tumor activity and manageable safety in patients with advanced ESCC.Randomized trials to evaluate this new combination strategy are warranted.Trial registration:This trial was registered on July 27,2018,at ClinicalTrials.gov(identifier:NCT03603756).

Irinotecan plus S-1 versus S-1 in patients with previously treated recurrent or metastatic esophageal cancer(ESWN 01):a prospective randomized,multicenter,open-labeled phase 3 trial

Background:The benefit of systemic treatments in esophageal squamous cell carcinoma(ESCC)which has pro-gressed after chemotherapy is still uncertain and optimal regimens based on randomized trials have not yet been established.We aimed to compare the efficacy of irinotecan plus S-1 with S-1 monotherapy in recurrent or metastatic ESCC patients who had resistance to platinum-or taxane-based chemotherapy.Methods:We conducted a prospective randomized,multicenter,open-label,phase 3 trial in 15 centers across China.Eligible patients were adults with histologically confirmed recurrent or metastatic ESCC,and were randomly assigned(ratio,1:1)to receive either irinotecan plus S-1(intravenous infusion of irinotecan[160 mg/m2]on day 1 and oral S-1[80-120 mg]on days 1-10,repeated every 14 days)or oral S-1 monotherapy(80-120 mg/day on days 1-14,repeated every 21 days)using a central computerized minimization procedure.The primary endpoint was progression-free survival(PFS).Results:Between December 23,2014 and July 25,2016,we screened 148 patients and randomly assigned 123 patients to receive either irinotecan plus S-1 regimen(n=61)or S-1 monotherapy(n=62).After a median follow-up of 29.2 months(95%confidence interval[CI]17.5-40.9 months),the median PFS was significantly longer in the irinotecan plus S-1 group than in the S-1 monotherapy group(3.8 months[95%CI 2.9-4.3 months]vs.1.7 months[95%CI 1.4-2.7 months],hazard ratio=0.58,95%CI 0.38-0.86,P=0.006).The objective response rates were 24.6%in the irinotecan plus S-1 group and 9.7%in the S-1 monotherapy group(P=0.002).The patients in the irinotecan plus S-1 group presented with increased rates of grade 3-4 leukopenia(16.4%vs.0%),neutropenia(14.8%vs.1.6%),and nausea(4.9%vs.0%).No significant difference in grade 3-4 diarrhea and no treatment-related deaths were observed in both groups.Conclusions: The combination of irinotecan with S-1 was similarly tolerable but significantly prolonged PFS compared to S-1 monotherapy as a second- or third-line treatment in patients with recurrent or metastatic ESCC.