Simulation and validation for count-based binary decision of target blood pressure achievement in home blood pressure monitoring data analysis for clinical practice

Introduction

Home blood pressure monitoring (HBPM) is a useful tool to identify hypertension and to decide whether a patient's blood pressure (BP) is controlled. The use of automatized oscillometric BP measurement devices has become increasingly popular with help of information technology and internet of things to the devices. However, applying HBPM to daily clinical practices is still challenging, because most patients with hypertension are in age groups not familiar to digital devices and internet and high BP criteria using average home BP values are often useless in outpatient clinics without easily accessible average BP calculation tools. Therefore, we developed a simple and straightforward method to interpret HBPM through counts of BP ≥135/85 mmHg.

Methods

We simulated 400 cases of HBPM using a random number generator function in statistical software. The simulated average home systolic BP (SBP) and its standard deviation (SD) were 125±15 mmHg and 12±5 mmHg and the number of HBP readings was 24 times. The simulated diastolic BP (DBP) was randomly selected to 50–75% of the SBP. The validation of the binary interpretation method was conducted using actual HBPM data from 386 subjects in a rural area of South Korea. Receiver operating characteristics curve analysis was conducted, and linear regression and logarithmic models were fitted between the numbers of home BP ≥135/85 mmHg and mean BP. Hypertension was defined with average home BP ≥135/85 mmHg.

Results

In the simulated cohort, hypertension was presented in 197 cases (49.3%). The C-index of the numbers of BP readings ≥135/85 mmHg was 0.994 (95% confidence interval [CI] 0.990–0.998), and ≥12 of 24 BP readings ≥135/85 mmHg showed a sensitivity of 95.4%, a specificity of 95.1% and an accuracy of 95.3% for the diagnosis of hypertension. In validation cohort, the numbers of home BP measurements varied from 8 to 81 times. The validation cohort similarly showed that the C-index of the ratio between the number of high BP readings (≥135/85 mmHg) to the number of BP measurements (R-NHBP/NBP) was 0.985 (95% CI, 0.976–0.994) and the best accuracy was shown at R-NHBP/NBP of ≥0.45. R-NHBP/NBP of ≥0.5 showed a sensitivity of 0.957, a specificity of 0.907 and an accuracy of 0.927. The accuracy of the R-NHBP/NBP of ≥0.5 decreased as SD and the range of SBP increased, whereas it did not change with the number of measurements (Figure 1). R-NHBP/NBP <0.2 predicted normotension and R-NHBP/NBP >0.8 predicted hypertension in 95% confidence. Mean widths of the 95 prediction intervals for the average SBP and DBP were 18.2 mmHg and 12.6 mmHg, respectively (Figure 2).

Conclusion

Counting the number of BP ≥135/85 mmHg can provide accurate assessments for the BP levels. R-NHBP/NBP of ≥0.5 is a simple and accurate marker of high BP in HBPM, and R-NHBP/NBP could be a useful tool to assess BP levels in patients practicing HBPM.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Trastuzumab deruxtecan (T-DXd; DS-8201) in patients with HER2-positive advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma: A randomized, phase II, multicenter, open-label study (DESTINY-Gastric01)

4513

Background: T-DXd is an antibody-drug conjugate composed of an anti-HER2 antibody, cleavable tetrapeptide-based linker, and topoisomerase I inhibitor. In a phase 1 trial of T-DXd (5.4 or 6.4 mg/kg), the objective response rate (ORR) was 43.2% (19/44) and median progression-free survival (mPFS) was 5.6 mo in patients with advanced HER2+ gastric cancer (GC). DESTINY-Gastric01 (DS8201-A-J202; NCT03329690) is an open-label, multicenter, randomized, phase 2 study of T-DXd in HER2-expressing advanced GC or GEJ adenocarcinoma; results are from the primary analyses for ORR and interim overall survival (OS) in HER2+ patients. Methods: Patients with centrally confirmed HER2+ (IHC 3+ or IHC 2+/ISH+ on archival tissue) GC that progressed on ≥ 2 prior lines were randomized 2:1 (T-DXd 6.4 mg/kg q3w or physician’s choice [PC] irinotecan or paclitaxel). All patients received prior HER2 therapy. Stratification factors were region, ECOG PS (0;1), and HER2 status. The primary endpoint was unconfirmed ORR by independent central review. Secondary endpoints were OS (alpha controlled), PFS, disease control rate (DCR), duration of response (DOR), and safety. Results: 187 patients received T-DXd (n = 125) or PC (n = 62 [55 irinotecan; 7 paclitaxel]); 79.7% Japan, 20.3% Korea. Patients had a median of 2 prior lines of therapy, and 44.4% had ≥ 3. At data cutoff (8 Nov 2019), 22.4% of T-DXd and 4.8% of PC patients remained on treatment. ORR was 51.3% (61/119; 11 CR and 50 PR) with T-DXd vs 14.3% (8/56; all PR) with PC ( P < .0001); confirmed ORR, 42.9% vs 12.5% ( P < .0001); DCR, 85.7% vs 62.5% ( P = .0005); mDOR, 11.3 vs 3.9 mo; mPFS, 5.6 vs 3.5 mo (HR, 0.47 [95% CI, 0.31-0.71]; P = .0003). OS was significantly prolonged with T-DXd (mOS, 12.5 vs 8.4 mo; HR, 0.59 [95% CI, 0.39-0.88]; P = .0097; prespecified O'Brien Fleming boundary, P = .0202); 12-month OS, 52.1% vs 28.9%. Grade ≥ 3 AEs occurred in 85.6% of patients with T-DXd vs 56.5% with PC; the most common were neutrophil count decreased (51.2%; 24.2%), anemia (37.6%; 22.6%), and white blood cell count decreased (20.8%; 11.3%). 12 patients (9.6%) had T-DXd–related interstitial lung disease (ILD; 2 grade 3, 1 grade 4, no grade 5) vs 0 with PC. 1 drug-related death (pneumonia [non-ILD] in the T-DXd arm) occurred. Conclusions: T-DXd demonstrated statistically significant and clinically meaningful improvements in ORR and OS compared with standard chemotherapy (paclitaxel or irinotecan) in patients with HER2+ advanced gastric or GEJ adenocarcinoma. Clinical trial information: NCT03329690 .

The association of tissue tumor mutational burden (tTMB) using the Foundation Medicine genomic platform with efficacy of pembrolizumab versus paclitaxel in patients (pts) with gastric cancer (GC) from KEYNOTE-061

4537

Background: KEYNOTE-061 (NCT02370498) was a randomized, open-label, phase 3 study of pembrolizumab vs paclitaxel in pts with advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma with tumor progression after first-line therapy (N = 592). In this analysis, we evaluated tTMB using FoundationOne CDx (F1CDx; Foundation Medicine) in pts with gastric or GEJ cancer in KEYNOTE-061. Methods: In pts with evaluable F1CDx tTMB data (n = 204), we analyzed the association of tTMB with confirmed objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) within each treatment arm using one-sided (pembrolizumab) and two-sided (paclitaxel) Wald test nominal P for logistic regression (ORR) and Cox proportional hazards regression (PFS; OS) adjusted for ECOG performance status; significance was prespecified at 0.05. The clinical utility of tTMB was assessed using the prespecified cutoff of 10 mut/Mb for F1CDx. Clinical data cutoff: Oct 26, 2017. Results: tTMB was positively associated with ORR ( P < 0.001; AUROC, 0.68), PFS ( P < 0.001), and OS ( P = 0.003) with pembrolizumab but not paclitaxel (ORR, P = 0.047; AUROC, 0.30; PFS, P = 0.605; OS, P = 0.084). Pt outcomes by tTMB cutoff are reported in the Table; prevalence of TMB ≥10 mut/Mb was 17%. In pts with microsatellite stable disease-only, HRs (95% CI) by treatment arm for OS by F1CDx cutoff were 0.40 (0.14-1.17) for tTMB ≥10 mut/Mb (n = 21) vs 0.97 (0.70-1.34) for tTMB <10 mut/Mb (n = 168). Conclusions: In this exploratory analysis from KEYNOTE-061, tTMB as determined by F1CDx demonstrated a positive association with clinical outcomes with pembrolizumab, but not paclitaxel, in pts with GC; these findings are consistent with those reported with whole exome sequencing. Pembrolizumab demonstrated an OS benefit vs paclitaxel in the subgroup with tTMB ≥10 mut/Mb, which remained when pts with microsatellite instability-high disease were excluded. Clinical trial information: NCT02370498 . [Table: see text]

Prognostic role of mismatch repair deficiency (MMR-D) in patients receiving first-line fluoropyrimidine and platinum (FP) doublet chemotherapy for metastatic and locally advanced unresectable gastric cancers (GCs)

4566

Background: Although chemotherapy has been suggested to have the potential to cause a detrimental effect on treatment outcomes of localized GC with MMR-D, it remains unclear whether chemotherapy for metastatic/recurrent/unresectable GC with MMR-D would also adversely affect the survival outcomes. Anti PD-1 antibody (Ab) showed remarkable efficacy in patients with MMR-D and is being actively investigated in combination with cytotoxic chemotherapy. Hence, we aim to evaluate the impact of MMR status on treatment outcomes of advanced GC. Methods: We reviewed our database to identify all patients with HER2 negative, metastatic, recurrent, and locally advanced unresectable GC who received FP doublet chemotherapy from January 2015 to August 2018. For those who had an available tumor tissue, MMR protein expression was assessed by immunohistochemistry (IHC) and correlated with clinical characteristics and treatment outcomes. Results: Out of 895 patients identified from the database, 543 underwent IHC testing for MMR. The median age was 58 years (range, 24 – 86) with male comprising 64.0%. Most patients had initially metastatic disease (n = 382, 70.3%) followed by recurrent (n = 127, 23.3%) and locally advanced unresectable disease (n = 34, 6.3%). MMR-D was found in 4.4% (n = 24) and associated with age ≥ 65 years (50% vs. 29.9%; P = 0.04) and signet ring cell histology (0% vs. 17.7%, P = 0.01). According to our prognostic model (Koo DH et al, 2011), only 4.2% of patients with MMR-D were classified as Poor-risk group (vs. 16.8% of patients with MMR-P, p= 0.10). In the Good-risk group, patients with MMR-D (n = 10) had significantly shorter median progression-free survival (PFS, 6.0 vs. 9.0 months, P = 0.05) and overall survival (OS, 10.1 vs 20.9 months, P = 0.047) compared to those with MMR-P (n = 188), while there was no significant difference in survival outcomes depending on MMR status in the Moderate and Poor-risk groups. In multivariate analysis for OS, MMR status was a significant prognostic factor for OS in Good-risk group GC patients. Conclusions: GC patients with MMR-D had poorer median PFS and OS than those with MMR-P on standard cytotoxic chemotherapy in the Good-risk group. Thus, for Good-risk GC patients with MMR-D, anti PD-1 Ab alone might be considered rather than combining cytotoxic chemotherapy. Further investigation with next-generation sequencing is in process to determine underlying molecular mechanisms and will be presented in ASCO 2020.

The association of molecular biomarkers with efficacy of pembrolizumab versus paclitaxel in patients with gastric cancer (GC) from KEYNOTE-061

4512

Background: KEYNOTE-061 (NCT02370498) was a randomized, open-label, phase 3 study of pembrolizumab vs paclitaxel in patients with advanced gastric or gastroesophageal junction adenocarcinoma with tumor progression after first-line therapy (N =592). We explored the association of tissue tumor mutational burden (tTMB) status and clinical outcomes in patients with GC enrolled in KEYNOTE-061, including the relationship with PD-L1 combined positive score (CPS) and microsatellite instability-high (MSI-H) status. Methods: In patients from KEYNOTE-061 with evaluable tumor and matched normal whole exome sequencing (WES) data (N = 420; pembrolizumab, 218; paclitaxel, 202), the association of tTMB (continuous log10 scale) with confirmed ORR and PFS by blinded central radiology review per RECIST v1.1, and OS was evaluated within each treatment arm using logistic regression (ORR) and Cox proportional hazards regression (PFS; OS). The clinical utility of tTMB was assessed using the prespecified cutoff of 175 mut/exome. Clinical data cutoff: October 26, 2017. Results: tTMB was significantly associated (α=0.05) with ORR, PFS, and OS in patients treated with pembrolizumab (one-sided P<0.001) but not paclitaxel (two-sided P>0.600). The area under the receiver operating characteristics curve for tTMB and response (pembrolizumab vs paclitaxel) was 0.68 (95% CI, 0.56-0.81) vs 0.51 (95% CI, 0.39-0.63). Patient outcomes by tTMB cutoff are reported in Table. There was low correlation between tTMB and PD-L1 CPS in both treatment arms (r<0.18). tTMB remained significantly associated with all clinical end points with pembrolizumab after adjusting for PD-L1 CPS and with PFS and OS after excluding MSI-H patients. Conclusions: This exploratory analysis from KEYNOTE-061 is the first to demonstrate a strong association between tTMB and response to pembrolizumab in patients with GC. Data further suggest tTMB is a significant and independent predictor beyond PD-L1 status. Clinical trial information: NCT02370498 . [Table: see text]

Pembrolizumab versus paclitaxel for previously treated patients with PD-L1–positive advanced gastric or gastroesophageal junction cancer (GC): Update from the phase III KEYNOTE-061 trial

4503

Background: KEYNOTE-061 ( NCT02370498) is a global phase 3 study of pembrolizumab vs paclitaxel as second-line therapy for GC. At the time of primary analysis (data cutoff: Oct 26, 2017), in patients with PD-L1–positive status (combined positive score [CPS] ≥1), pembrolizumab did not significantly prolong overall survival (OS) vs paclitaxel (9.1 months vs 8.3 months) but did elicit a longer duration of response (DOR) and a favorable safety profile vs paclitaxel. We present results of KEYNOTE-061 in patients with CPS ≥1, ≥5, and ≥10 after 2 additional years of follow-up (cutoff: Oct 7, 2019). Methods: Adult patients with GC that progressed after platinum + fluoropyrimidine chemotherapy were randomly assigned 1:1 to pembrolizumab 200 mg Q3W for up to 35 cycles (~2 y) or standard-dose paclitaxel. OS and progression-free survival (PFS) in the CPS ≥1 population were the primary end points. Comparisons were made using stratified log-rank tests. Results: At the time of this analysis, 366/395 patients with CPS ≥1 had died (92.6%). Pembrolizumab prolonged OS vs paclitaxel in PD-L1–positive patients (Table). No significant differences appeared between groups in PFS (Table). Objective response rate (ORR) was higher for pembrolizumab in the CPS ≥10 group, and DOR was longer with pembrolizumab using all CPS cutoffs (Table). There were fewer drug-related adverse events (AEs) with pembrolizumab than paclitaxel in the overall population (53% vs 84%). Conclusions: This long-term analysis found that second-line pembrolizumab prolonged OS among patients with PD-L1–positive GC and led to fewer drug-related AEs vs paclitaxel. Clinical trial information: NCT02370498 . [Table: see text]

Diagnostic accuracy of CT-staging of advanced gastric cancer following neoadjuvant chemotherapy

4551

Background: Neoadjuvant or perioperative chemotherapy has been accepted as a standard treatment globally in patients (pts) with locally advanced gastric cancer (LAGC). In PRODIGY phase III study (n = 530), we have demonstrated that neoadjuvant chemotherapy with DOS regimen (docetaxel, oxaliplatin, S-1) led to significant tumor downstaging and improved PFS in Korean LAGC pts (Kang, et al. ESMO 2019). Although CT has been performed to re-stage the tumor after neoadjuvant chemotherapy, there has been a relative paucity of diagnostic accuracy data. This study is to evaluate the diagnostic performance of restaging of LAGC after neoadjuvant chemotherapy using CT in PRODIGY study population. Methods: Of 266 pts, who had been diagnosed LAGC of T2-4 or N+ stage as assessed with CT and randomized to neoadjuvant chemotherapy arm (CSC) in PRODIGY study, 214 pts underwent gastrectomy were included in this analysis. The post-chemotherapy T- and N- stage was determined based on CT scan taken just prior to surgery and compared with the pathologic stage (AJCC 7th edition). Two experienced radiologists independently evaluated depth of primary tumor and reached consensus if any discrepancy between two readers. Diameter of short axis of the largest regional lymph node was measured to predict metastatic lymph node. Result of histopathologic T- and N-staging using surgical specimen was used as reference standard. Results: The study cohort consisted of pathologic T0 (n = 22), T1(n = 39), T2(n = 31), T3(n = 79), and T4(n = 43). The overall diagnostic accuracy of CT was 45%. For each T-stage, accuracy of T0,T1,T2,T3, and T4 was 0%, 26%, 29%, 55% and 79%, respectively. Rate of over- and under- staging was 47% and 8%, respectively. Accuracy for prediction of downstaging to early gastric cancer (T0-T1) was 83%. Interobserver agreement of T-staging was moderate (k = 0.41). There were 98 patients of N+ and 116 patients of N- at histopathology. Area under the curve of receiver operating characteristics to differentiate lymph node metastasis was 0.63. Sensitivity and specificity of size criteria of the largest lymph node (cut off value: > 6mm, > 7mm, and > 8mm) to predict pathologic N+ were 90% and 17%, 78% and 34%, and 68% and 51%, respectively. Conclusions: Re-staging using CT after neoadjuvant chemotherapy showed suboptimal accuracy and over-staged residual tumor. However, it predicted downstaging of gastric cancer with high accuracy.

Results of the JAVELIN Gastric 100 phase 3 trial: avelumab maintenance following first-line (1L) chemotherapy (CTx) vs continuation of CTx for HER2− advanced gastric or gastroesophageal junction cancer (GC/GEJC)

278

Background: We report the primary analysis of JAVELIN Gastric 100, which compared avelumab (anti–PD-L1) maintenance after 1L CTx vs continued CTx in patients (pts) with GC/GEJC. Methods: In this global, open-label, phase 3 trial (NCT02625610), eligible pts had previously untreated, unresectable, locally advanced/metastatic (LA/M) HER2− GC/GEJC. Pts without progressive disease (PD) after 12 weeks of 1L oxaliplatin/fluoropyrimidine induction were randomized 1:1 to avelumab 10 mg/kg Q2W switch maintenance or continued CTx, stratified by region (Asia vs non-Asia). Primary endpoint was overall survival (OS) post induction in all randomized or PD-L1+ (≥1% of tumor cells, 73-10 assay) pts. Results: 805 pts received induction CTx and 499 pts were randomized (avelumab, n = 249; CTx, n = 250). At data cutoff (Sep 13, 2019), minimum follow-up was 18 months. In the avelumab and CTx arms, median OS post induction/randomization was 10.4 months (95% CI 9.1-12.0) vs 10.9 months (95% CI 9.6-12.4), hazard ratio (HR) 0.91 (95% CI 0.74-1.11; p = 0.1779); 24-month OS rates were 22.1% (95% CI 16.8-28.0) vs 15.5% (95% CI 10.8-20.9), respectively. The HR for OS in PD-L1+ pts (n = 54) was 1.13 (95% CI 0.57-2.23). No OS trend was seen in Asian pts (n = 114; HR 0.90 [95% CI 0.59-1.36]) or other subgroups, except for a potential benefit with avelumab in pts with no metastatic sites at randomization (n = 60; HR 0.52 [95% CI 0.28-0.98]). Progression-free survival was similar between arms (HR 1.04 [95% CI 0.85-1.28]). In the avelumab vs CTx arms, objective response rates (post randomization only) were 13.3% (95% CI 9.3-18.1) vs 14.4% (95% CI 10.3-19.4), and 12-month rates for duration of response were 62.3% (95% CI 40.9-77.9) vs 28.4% (95% CI 13.2-45.7), respectively. Treatment-related adverse event rates (all grades/grade ≥3) were 61.3%/12.8% with avelumab and 77.3%/32.8% with CTx. Conclusions: Avelumab maintenance showed clinical activity and favorable safety vs continued CTx in pts with LA/M GE/GEJC; however, JAVELIN Gastric 100 did not meet its primary objective of demonstrating superior OS in the randomized or PD-L1+ population. Clinical trial information: NCT02625610.

Predictive role of mismatch repair deficiency (MMR-D) in patients receiving first-line fluoropyrimidine and platinum (F-P) doublet chemotherapy for metastatic and locally advanced unresectable gastric cancers (GC)

444

Background: Although adjuvant chemotherapy has been known to have a detrimental effect on MMR-D patients (pts) with resectable GC, it is unclear whether palliative chemotherapy for advanced GC would also adversely affect the survival outcome of MMR-D pts. Immune-checkpoint inhibitor (ICI) monotherapy was approved as a standard treatment for ≥ 3rd line of advanced GC and also showed a remarkable efficacy in MMR-D pts regardless of line of therapy. ICI is now being investigated in combination with 1st-line cytotoxic chemotherapy. Hence, we aim to evaluate the prognostic impact of MMR on cytotoxic chemotherapy in advanced GC. Methods: We reviewed our prospective database to identify pts with initally metastatic, recurrent and locally advanced unresectable GC who received F-P doublet from 2015 to 2018. MMR was assessed by immunohistochemistry with previously-collected tumor tissue and correlated with clinical characteristics and survival outcomes. Results: Out of 892 pts identified from the database, 543 underwent MMR test [382 initally metastatic (70.3%); 127 recurrent (23.3%); 32 locally advanced unresectable (6.3%)]. Median age was 58 years (range, 24–86) with male comprising 64.0%. MMR-D was found in 4.4% (n = 24) and associated with age ≥ 65 (50% vs 29.9%; P = 0.037), antrum-origin (62.5% vs 34.1%, P = 0.004) and well/moderately-differentiated histology (41.7% vs 25.8%, P = 0.110). According to our prognostic model (Koo DH et al, 2011), MMR-D pts were less likely to be classified into poor-risk group (4.2% vs 16.8%, P = 0.102). In good-risk group, MMR-D pts had significantly shorter PFS (6.0 vs 9.0 months, P = 0.045) and OS (10.1 vs 20.9 months, P = 0.047), while pts in moderate and poor risk group showed no difference in survival depending on MMR status. Conclusions: MMR-D GC showed significantly shorter PFS and OS on F-P doublet in good-risk pts and further investigation is needed to determine underlying molecular mechanisms. With the negative impact of MMR-D on the effect of cytotoxic chemotherapy, exclusion of MMR-D pts should be considered in future trials of ICI and cytotoxic chemothrapy combination.

Second-line chemotherapy versus supportive cancer treatment in advanced gastric cancer: a meta-analysis

BACKGROUND

Many patients with refractory or relapsed gastric cancer after first-line chemotherapy have received salvage chemotherapy in routine clinical practice. However, there was no evidence to support this treatment until recent phase III trials demonstrated substantial prolongation of overall survival. Therefore, we conducted a meta-analysis of these trials and investigated whether second-line chemotherapy was more effective than best supportive care.

PATIENTS AND METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 1, 2013), MEDLINE (1950 to March week 4, 2013) and EMBASE (1980-2013, week 13). In addition, we searched all abstracts and virtual meeting presentations from the American Society of Clinical Oncology (ASCO) conferences held between 2004 and 2013.

RESULTS

The search process yielded 578 studies, two of which were randomized phase III trials that compared chemotherapy with supportive care. From the abstracts and virtual meeting presentations of ASCO held between 2004 and 2013, 127 abstracts were identified that evaluated second-line chemotherapy; only one relevant abstract was included in the meta-analysis. A total of 410 patients were eligible for analysis, of whom 150 received docetaxel chemotherapy, and 81 received irinotecan chemotherapy. A significant reduction in the risk of death [HR = 0.64, 95% confidence interval (CI) 0.52-0.79, P < 0.0001] was observed with salvage chemotherapy. When the analysis was restricted to irinotecan or docetaxel, there was still significant reduction in the risk of death with each chemotherapeutic agent. The HR was 0.55 (95% CI 0.40-0.77, P = 0.0004) for irinotecan and 0.71 (95% CI 0.56-0.90, P = 0.004) for docetaxel.

CONCLUSION

This meta-analysis demonstrated evidence to support second-line chemotherapy in advanced gastric cancer.

Sorafenib in patients with metastatic gastrointestinal stromal tumors who failed two or more prior tyrosine kinase inhibitors: a phase II study of Korean gastrointestinal stromal tumors study group

PURPOSE

To evaluated the efficacy and safety of sorafenib in patients with advanced gastrointestinal stromal tumors (GIST) who failed to previous standard treatments.

EXPERIMENTAL DESIGN

Thirty-one patients with measurable metastatic GIST who failed both imatinib and sunitinib were accrued. Sorafenib was administered orally at 400 mg twice daily until disease progression or development of intolerance. The primary endpoint was disease control rate (response + stable disease, DCR) at 24 weeks.

RESULTS

Sorafenib was well tolerated, with hand-foot skin reaction, fatigue, hypertension, and abdominal pain being the most frequent adverse events. The relative dose intensity of sorafenib during the first 6 months was >80%. Four patients achieved partial response (response rate 13%, 95% CI 1-25%), and 16 (52%) had stable disease. DCR at 24 weeks was measured as 36% (95% CI 19-52%). Median progression-free and overall survivals were 4.9 and 9.7 months, respectively. Progression-free survival of patients with prior use of nilotinib (P = .0085) and with primary genotypes other than KIT exon 11 mutation (P = .0341) was significantly shorter than that of patients without.

CONCLUSIONS

Sorafenib showed antitumor activity in this population of imatinib and sunitinib pretreated GIST. With sorafenib, about one third of patients can maintain disease control for more than 24 weeks.

Effect of supplementation of Bacillus subtilis LS 1-2 to broiler diets on growth performance, nutrient retention, caecal microbiology and small intestinal morphology

Present study investigated the effect of dietary supplementation of Bacillus subtilis LS 1-2 on growth performance, apparent nutrient retention, caecal microbial population and intestinal morphology in broilers. Three hundred and twenty day-old Ross broiler chicks were randomly allotted to four treatments on the basis of BW in a randomized complete block design. Experimental diets were fed in two phases: starter (d 0-21) and finisher (d 22-35). Dietary treatments were basal diet supplemented with 0% (control), 0.15%, 0.30% and 0.45% B. subtilis LS 1-2. Supplementation of increasing levels of B. subtilis LS 1-2 showed linear improvement (P<0.05) in growth performance and apparent nutrient retention. At d 35, birds supplemented with increasing levels of B. subtilis LS 1-2 showed decrease in caecal Clostridium and Coliform count (linear, P<0.05). Moreover, supplementation of B. subtilis LS 1-2 increased (linear, P<0.05) villus height and villus height to crypt depth ratio in both duodenum and ileum. Results obtained in the present study indicate that B. subtilis LS 1-2 can be used as a growth promoter in broiler diets and can improve intestinal microbial balance and gut health of broilers.

Investigation of papulopustular eruptions caused by cetuximab treatment shows altered differentiation markers and increases in inflammatory cytokines

BACKGROUND

Epidermal growth factor receptor (EGFR) critically regulates tumour cell division, survival and metastasis. Agents that inhibit EGFR have been used in the treatment of advanced-stage malignancies, but cause variable cutaneous side-effects, most often papulopustular eruptions and xerosis.

OBJECTIVES

We assayed expression of inflammatory cytokines [interleukin (IL)-1alpha, tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, human leucocyte antigen (HLA)-DR and intercellular adhesion molecule (ICAM)-1], differentiation markers (filaggrin, involucrin and loricrin) and phosphorylated EGFRs (pEGFRs) in papulopustular eruptions to determine the association between these markers and the eruptions caused by cetuximab.

PATIENTS/METHODS

Twelve papulopustular lesion biopsies were selected from patients with colon cancer who had received cetuximab treatment. Immunohistochemistry and immunofluorescence with a confocal laser scanning microscopy were performed.

RESULTS

Filaggrin expression decreased and expression of involucrin, various inflammatory markers (IL-1alpha, TNF-alpha, ICAM-1 and HLA-DR) increased and the expression of pEGFR was markedly downregulated in papulopustular eruptions. In perilesions, decreased pEGFR expression was noted in hair follicles compared with interfollicular epidermis. The increase of IL-1alpha and TNF-alpha was observed in perilesions as in the lesions.

CONCLUSIONS

The early inflammatory events (IL-1alpha and TNF-alpha expression) seen, and the lack of pEGFR in perilesional follicles, indicate that inflammatory events induced by EGFR inhibition may initiate papulopustular eruptions along with the altered differentiations. The decrease of filaggrin may contribute to the pathogenesis of the xerosis caused by cetuximab.

Prognostic significance of p53 gene mutations and protein overexpression in localized gastrointestinal stromal tumours

AIMS

Mutation of c-kit is a relatively early event in the tumorigenesis of gastrointestinal stromal tumours (GISTs). The aim was to determine the prognostic significance of p53 alterations as an additional genetic change in GISTs.

METHODS AND RESULTS

We reviewed 125 patients with localized GISTs subjected to complete resection between 1990 and 2002. Mutational analyses of c-kit exons 9, 11, 13 and 17, p53 exons 4-8 and immunohistochemistry for p53 protein were conducted using paraffin-embedded tissues. Alterations of p53 were observed in 50 patients (40.0%). Based on the National Institutes of Health's risk category, p53 alterations were noted more frequently in the higher risk categories (P = 0.041). With a median follow-up of 56.5 months (range: 2.3-126.8), 5-year relapse-free survival (RFS) rates were 61.7% without p53 alterations, compared with only 40.2% with p53 alterations (P = 0.009). Multivariate analysis indicated that p53 alterations comprised an independent, poor prognostic factor for RFS, in addition to c-kit mutations, large size, a high mitotic count and non-gastric primary sites.

CONCLUSIONS

Alterations in p53 were more commonly observed in localized GISTs at higher risk of relapse. This suggests that they are significant as an independent, poor prognostic factor.

Cutaneous metastasis resembling acute dermatitis in patient with advanced gastric cancer

The most common metastatic sites from gastric cancer are the liver, intra-abdominal lymph nodes, ovary and peritoneal cavity. Cutaneous metastasis of gastric cancer is rare, and most cutaneous metastases are typically solitary, nodular, have a firm consistency, and are red or hyperpigmented. Thus, cutaneous metastasis is easily distinguished from other skin disease. We report a case of a 60-year-old woman with cutaneous metastasis of gastric cancer, whose facial skin showed painless pruritic eczema, resembling acute dermatitis. She had earlier undergone a total gastrectomy for advanced gastric cancer in our hospital. After 14 months, she developed eczematous facial lesions; the presumptive diagnosis was acute dermatitis. However, skin biopsy unexpectedly revealed cutaneous metastasis of gastric cancer. After 6 months of systemic chemotherapy with capecitabine and cisplatin, the cutaneous metastasis was markedly improved and a clinically complete remission was accomplished.

Adjuvant chemotherapy with 5-fluorouracil, doxorubicin and mitomycin-C (FAM) for 6 months after curative resection of gastric carcinoma

AIM

This study aimed to evaluate the efficacy and safety of 5-fluorouracil (5-FU), doxorubicin and mitomycin-C (FAM) adjuvant chemotherapy in patients who had undergone curative resection of gastric carcinoma.

METHODS

From Nov 1999 to Jan 2002, 291 consecutive patients with stage IB-IIIB gastric adenocarcinoma were given FAM adjuvant chemotherapy. Chemotherapy comprised intravenous 5-FU 600 mg/m(2) (days 1, 8, 29 and 36), doxorubicin 30 mg/m(2) (days 1 and 29) and mitomycin-C 10 mg/m(2) (day 1), every 8 weeks for 6 months.

RESULTS

The median follow-up time was 60.6 months, 92 patients died, and 93 patients had recurrent disease. The 5-year overall survival (OS) rates were 85.9% for stage IB, 72.1% for stage II, 58.0% for stage IIIA, and 48.2% for stage IIIB (p=0.002). The 5-year relapse-free survival (RFS) rates were 85.2% for stage IB, 71.2% for stage II, 53.3% for stage IIIA, and 39.2% for stage IIIB (p<0.001). A total of 769 cycles of chemotherapy were delivered, and 15 patients experienced grade 3 or higher leukopenia. The most common grade 3 or higher non-hematologic toxicity was nausea/vomiting (11 patients), followed by stomatitis (3 patients).

CONCLUSIONS

Adjuvant chemotherapy with FAM for 6 months for gastric carcinoma indicated comparable RFS and OS with an acceptable toxicity profile.

Efficacy of PET/CT in the accurate evaluation of primary colorectal carcinoma

AIM

This study was performed to assess in the accurate evaluation of primary colorectal carcinoma using PET/CT.

METHODS

One hundred patients with primary colorectal carcinoma were evaluated during 2004. All patients underwent PET/CT when their preoperative serum carcinoembryonic antigen was >or=10 ng/mL or when CT showed equivocal findings. The appropriateness of PET/CT-induced changes was noted by subsequent operative findings and follow-up.

RESULTS

PET/CT more detected 15 intra-abdominal metastatic lesions than abdomino-pelvic CT scan. PET/CT showed true negative findings in 13 patients and false positive or negative findings in 10. Due to PET/CT results, management plans were altered in 27 patients; 9 had inter-modality changes, 10 received more extensive surgery, and 8 avoided unnecessary procedures.

CONCLUSIONS

PET/CT altered management plan in 24% of patients with primary colorectal carcinoma in correct direction. These findings suggest that PET/CT should be considered a part of standard work up for preoperative evaluation in a subset of patients with colorectal carcinoma.

Improved therapeutic outcomes of DLBCL after introduction of rituximab in Korean patients

The addition of rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) has been shown to improve the outcome in all age groups with newly diagnosed diffuse large B-cell lymphoma (DLBCL). We conducted a retrospective analysis to evaluate the impact of this combination therapy on DLBCL outcomes in Korea. From October 2001 to June 2004, newly diagnosed DLBCL patients in nine Korean institutes were included. All of these 81 patients were treated with three or more cycles of rituximab plus CHOP (R-CHOP) combination chemotherapy (R group), and followed for a minimum of 12 months. For comparison, a historical cohort of patients was used and analyzed for "Clinicopathologic characteristics of Korean non-Hodgkin's lymphomas (NHLs) based on Revised American Lymphoma (REAL) classification" in 1999. Among the 1,098 NHL patients, the data of 214 DLBCL patients, who were treated with CHOP chemotherapy in first-line, were analyzed (C group). We compared outcomes between the C group and the R group. A total of 295 patients were evaluated (C group, 214; R group, 81). The complete response (CR) rate was higher in R group (73 vs 91%, p=0.001). The 2-year event-free survival (EFS) rate was significantly higher in R group (78 vs 85%, p=0.0194). This survival benefit was maintained in high-risk patients according to the international prognostic index (IPI) (p=0.0039), regardless of age. However, there was no significant difference in low-risk patients. The addition of rituximab to CHOP combination chemotherapy for DLBCLs showed improved outcomes, particularly in high-risk group according to the IPI. Long-term follow-up results will be needed to confirm these results.

Phase II study of capecitabine plus cisplatin as first-line chemotherapy in advanced biliary cancer

BACKGROUND

A phase II study was conducted to assess the efficacy and tolerability of substituting capecitabine for 5-fluorouracil in combination with cisplatin in patients with advanced biliary cancer.

PATIENTS AND METHODS

Patients with previously untreated metastatic or unresectable measurable biliary adenocarcinoma received oral capecitabine 1250 mg/m(2) twice daily on days 1-14, and intravenous cisplatin 60 mg/m(2) on day 1. This cycle was repeated every 21 days.

RESULTS

Forty-two patients were enrolled in this study. Of these, 38 were assessable for efficacy and 41 were assessable for safety. A median of three cycles of treatment (range one to eight) were administered. One patient achieved a complete response, and eight had partial responses, giving an overall response rate of 21.4% in the intention-to-treat population (95% confidence interval 9.1% to 33.9%). The median response duration was 5.1 months. The median time to progression and median overall survival were 3.7 and 9.1 months, respectively. The most common grade 3/4 adverse events were neutropenia (20% of patients), vomiting (12%), diarrhea (7%) and stomatitis (5%). There were no treatment-related deaths.

CONCLUSIONS

The combination of capecitabine and cisplatin has promising antitumor activity and is well tolerated in patients with advanced biliary cancer.

Evaluation of premalignant potential in oral lichen planus using interphase cytogenetics

This study attempted to evaluate whether oral lichen planus (OLP) has the potential to progress to oral squamous cell carcinoma (OSCC) by comparing the degree of genetic instability between clinically-curable OLP and lesions that progressed to OSCC. Fifteen cases of steroid-responsive OLP and two cases of lichenoid dysplasia (LD) that progressed to OSCC were used for this study. Chromosome in situ hybridization (CISH) was performed for chromosomes 9 and 17. The fraction of polysomic and monosomic cells for chromosome 9 increased in mucosal epithelium compared to those of lymphocytes in OLP. This difference was statistically significant (P=0.0017, 0.0054, respectively). Two LD patients showed 15.38% and 22.58% of PI for chromosome 9. In OSCC that developed from LD, the fraction of monosomic cells for chromosome 9 increased by more than 70%. We concluded that LD should be treated as a high-risk premalignant lesion and strongly suggest that the monosomy of chromosome 9 may have a critical role in progress to malignancy from LD.

Methylation of specific CpG sites in the promoter region could significantly down-regulate p16(INK4a) expression in gastric adenocarcinoma

Silencing of p16(INK4a) by methylation of the CpG islands in the promoter region has been found to be an alternative mechanism of inactivation in several tumors. However, in gastric carcinoma, the relationship between methylation status and the transcriptional silencing of the p16 gene remains to be clarified. In this study, we investigated whether methylation of a few specific CpG sites in the promoter region could significantly down-regulate p16 activity in the tumorigenesis of gastric carcinoma. By Southern analysis and bisulfite-modified genomic sequencing of 9 gastric-carcinoma cell lines, we found that the 5 cell lines (55.5%) not expressing p16 mRNA had methylated CpG sites at the promoter region of p16. In addition, we analyzed the p16-protein expression of 28 primary gastric carcinomas and their normal counterparts by immunohistochemical staining (IHC) on paraffin sections. Loss of p16 expression was detected in 6 cases (22%). In 5 out of these 6 (83%), the actual p16 gene was inactivated by de novo methylation of the promoter sites. Taken together, these results suggest a strong correlation between de novo methylation of a few specific CpG sites and transcriptional silencing of the p16 gene in gastric carcinoma.

Methylation of specific CpG sites in the promoter region could significantly down-regulate p16(INK4a) expression in gastric adenocarcinoma

Silencing of p16(INK4a) by methylation of the CpG islands in the promoter region has been found to be an alternative mechanism of inactivation in several tumors. However, in gastric carcinoma, the relationship between methylation status and the transcriptional silencing of the p16 gene remains to be clarified. In this study, we investigated whether methylation of a few specific CpG sites in the promoter region could significantly down-regulate p16 activity in the tumorigenesis of gastric carcinoma. By Southern analysis and bisulfite-modified genomic sequencing of 9 gastric-carcinoma cell lines, we found that the 5 cell lines (55.5%) not expressing p16 mRNA had methylated CpG sites at the promoter region of p16. In addition, we analyzed the p16-protein expression of 28 primary gastric carcinomas and their normal counterparts by immunohistochemical staining (IHC) on paraffin sections. Loss of p16 expression was detected in 6 cases (22%). In 5 out of these 6 (83%), the actual p16 gene was inactivated by de novo methylation of the promoter sites. Taken together, these results suggest a strong correlation between de novo methylation of a few specific CpG sites and transcriptional silencing of the p16 gene in gastric carcinoma.

Alteration of signal-transducing molecules and phenotypical characteristics in peripheral blood lymphocytes from gastric carcinoma patients

The mechanisms underlying the impaired immune response frequently observed in cancer patients are not fully understood. Alteration of T-cell-associated signal transduction molecules has recently been implicated in immune suppression in tumor-bearing hosts. Furthermore, T cells from tumor-bearing host, irrespective of the presence of the zeta-chain, showed a lack of proliferative activity and cytotoxic function. In the present study, we investigated the expression of the zeta-chain molecule and the p56(lck) and p59(fyn) protein tyrosine kinase (PTK) levels in peripheral blood T lymphocytes (T-PBL) from patients with advanced gastric carcinomas; for this, flow cytometric analysis and immunoblotting, respectively, were used. We also compared the results of flow cytometric analysis of PBL between stomach cancer patients and normal healthy volunteers. In T-PBL from 22 tumor-bearing hosts, significantly reduced zeta-chain expression (16/22, 73%) was observed. Moreover, the expression level of p56(lck) in T-PBL from patients was significantly lower than that of p59(fyn). Flow cytometric analysis of T-PBL indicated a markedly increased CD8+28- cell population in T-PBL from 19 tumor-bearing hosts.

Effect of rebamipide on the glycosaminoglycan content of the ulcerated rat stomach

To elucidate the mechanism of the anti-ulcer effect of rebamipide (2-(4-chlorobenzoylamino)-3-[2-(1H)-quinolinon-4-yl] propionic acid), changes in glycosaminoglycan (GAG), uronic acid and hexosamine contents of stomach tissue were examined in rats treated with the ulcer-inducing agents and/or rebamipide. Uronic acid and hexosamine contents in acid hydrolysates of stomach tissue were increased after diethyldithiocarbamate (DDC, 800 mg/kg, s.c.) or histamine (300 mg/kg, i.p.) treatment, and similar changes in the GAG, uronic acid, and hexosamine levels were observed in stomach tissue extracts. Pretreatment with rebamipide (60 mg/kg, i.p.) resulted in an additional increase in the contents of the above components after DDC or histamine treatment. However, rebamipide treatment alone did not increase the gastric contents of GAG and GAG components in normal rats. Gel filtration chromatography of extracted GAGs suggested that DDC, histamine and rebamipide treatments do not cause a change in the aggregated forms of gastric GAGs. These results suggest that rebamipide stimulates the GAG synthesis in the ulcerated stomach and that this effect may contribute to the healing process of gastric ulcer.

Head-up tilt test with isoproterenol provocation in syncope of unknown origin

OBJECTIVES

Head-up tilt test (HUT) has been reported to be useful in the evaluation of syncope of unknown origin (SUO). However, the sensitivity of HUT with no pharmacologic provocation was relatively low and variable, ranging 32 approximately 70%. Therefore, several protocols of HUT with different degrees and durations of the tilt and modes of provocation were proposed. The purpose of this study was to determine the value of the multi-stage head-up tilt test with isoproterenol provocation (HUT-isp) in the evaluation of SUO and drug efficacy.

METHODS

Sixty-seven patients presenting with SUO and 30 control subjects with no history of syncope underwent the HUT-isp. Blood pressure (BP) was measured every 2 min and whenever the patient complained of any symptom, and cardiac rhythm was continuously monitored. The HUT-isp consisted of 3 stages: first for 20 min with no provocation, second and third stages with infusion of isoproterenol for 10 min each at a rate of 2 micrograms/min and 5 micrograms/min, respectively. A positive HUT-isp was defined when syncope or presyncope was reproduced, accompanied by hypotension (< 80 mmHg) or bradycardia (< 40/min) or both, and positive responses were classified into vasodepressive, cardioinhibitory and mixed type.

RESULTS

The HUT-isp was positive in 56 (83.6%) of 67 patients with SUO and 10 (33.3%) of 30 control subjects. The type of positive responses was vasodepressive in 41 (73.2%), cardioinhibitory in 4 (7.1%) and mixed in 11 (19.6%). The sensitivity of the HUT-isp in diagnosing vasovagal syncope was 83.6%, specificity 66.7% and positive predictive value 84.8%. Positive responses were developed most frequently in the 3rd stage: 76.8% in patients, 70% in controls. The effect of 3 drugs (carteolol, aminophylline and disopyramide) was evaluated in 27 patients with a repeat HUT-isp. Carteolol was effective in 12 (85.7%) of 14 patients, disopyramide in 7 (58. 3%) of 12 and aminophylline in 1 (14.3%) of 7. During the follow-up period of 175 +/- 212 days (26 approximately 623 days), none of the 20 patients with a negative repeat HUT-isp developed a recurrent syncope.

CONCLUSION

The HUT-isp is thought safe and useful to evaluate syncope of unknown origin and to guide effective drug therapy.