Effectiveness and safety of primary prophylaxis of G-CSF during chemotherapy for prostate cancer, Japanese clinical guideline for appropriate use of G-CSF: clinical practice guidelines for the use of G-CSF 2022

BACKGROUND

Docetaxel (DTX) is commonly used as a primary chemotherapy, and cabazitaxel (CBZ) has shown efficacy in patients who are DTX resistant. Primary prophylactic granulocyte colony stimulating factor (G-CSF) therapy is currently used with CBZ treatment in routine clinical care in Japan.

METHODS

In this study, we performed a systematic review following the Minds guidelines to investigate the effectiveness and safety of primary prophylaxis with G-CSF during chemotherapy for prostate cancer and to construct G-CSF guidelines for primary prophylaxis use during chemotherapy. A comprehensive literature search of various electronic databases (PubMed, Cochrane Library, and Ichushi) was performed on January 10, 2020, to identify studies published between January 1990 and December 31, 2019 that investigate the impact of primary prophylaxis with G-CSF during CBZ administration on clinical outcomes.

RESULTS

Ultimately, nine articles were included in the qualitative systematic review. Primary G-CSF prophylaxis during CBZ administration for metastatic castration-resistant prostate cancer was difficult to assess in terms of correlation with overall survival, mortality from infection, and patients' quality of life. These difficulties were owing to the lack of randomized controlled trials comparing patients with and without primary prophylaxis of G-CSF during CBZ administration. However, some retrospective studies have suggested that it may reduce the incidence of febrile neutropenia.

CONCLUSION

G-CSF may be beneficial as primary prophylaxis during CBZ administration for metastatic castration resistant prostate cancer, and we made a "weak recommendation to perform" with an annotation of the relevant regimen.

Effectiveness and safety of primary prophylaxis of granulocyte colony-stimulating factor during dose-dense chemotherapy for urothelial cancer: Clinical Practice Guidelines for the Use of G-CSF 2022

Granulocyte colony-stimulating factor (G-CSF) decreases the incidence, duration, and severity of febrile neutropenia (FN); however, dose reduction or withdrawal is often preferred in the management of adverse events in the treatment of urothelial cancer. It is also important to maintain therapeutic intensity in order to control disease progression and thereby relieve symptoms, such as hematuria, infection, bleeding, and pain, as well as to prolong the survival. In this clinical question, we compared treatment with primary prophylactic administration of G-CSF to maintain therapeutic intensity with conventional standard therapy without G-CSF and examined the benefits and risks as major outcomes. A detailed literature search for relevant studies was performed using PubMed, Ichu-shi Web, and Cochrane Library. Data were extracted and evaluated independently by two reviewers. A qualitative analysis of the pooled data was performed, and the risk ratios with corresponding confidence intervals were calculated and summarized in a meta-analysis. Seven studies were included in the qualitative analysis, two of which were reviewed in the meta-analysis of dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) therapy, and one randomized controlled study showed a reduction in the incidence of FN. Primary prophylactic administration of G-CSF may be beneficial, as shown in a randomized controlled study of dose-dense MVAC therapy. However, there are no studies on other regimens, and we made a "weak recommendation to perform" with an annotation of the relevant regimen (dose-dense MVAC).

A Phase 2 Study of Encorafenib in Combination with Binimetinib in Patients with Metastatic BRAF-Mutated Thyroid Cancer in Japan

Background: Driver mutations at BRAF V600 are frequently identified in papillary thyroid cancer and anaplastic thyroid cancer (ATC), in which BRAF inhibitors have shown clinical effectiveness. This Japanese phase 2 study evaluated the efficacy and safety of a BRAF inhibitor, encorafenib, combined with an MEK inhibitor, binimetinib, in patients with BRAF V600-mutated thyroid cancer. Methods: This phase 2, open-label, uncontrolled study was conducted at 10 institutions targeted patients with BRAF V600-mutated locally advanced or distant metastatic thyroid cancer not amenable to curative treatment who became refractory/intolerant to ≥1 previous vascular endothelial growth factor receptor-targeted regimen(s) or were considered ineligible for those. The primary endpoint was centrally assessed objective response rate (ORR). The secondary endpoints included duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety. Results: We enrolled 22 patients with BRAFV600E-mutated thyroid cancer: 17 had differentiated thyroid cancer (DTC), and 5 had ATC. At data cutoff (October 26, 2022), the median follow-up was 11.5 (range = 3.4-19.0) months. The primary endpoint of centrally assessed ORR was 54.5% (95% confidence interval [CI] 32.2-75.6; partial response in 12 patients and stable disease in 10). The ORRs in patients with DTC and ATC were 47.1% (8 of 17) and 80.0% (4 of 5), respectively. The medians for DOR and PFS by central assessment and for OS were not reached in the overall population, the DTC subgroup, or the ATC subgroup. At 12 months, the rate of ongoing response was 90.9%, and the PFS and OS rates were 78.8% and 81.8%, respectively. All patients developed ≥1 adverse events (AEs): grade 3 AEs in 6 patients (27.3%). No patients developed grade 4-5 AEs. The most common grade 3 AE was lipase increased (4 patients [18.2%]). Those toxicities were mostly manageable with appropriate monitoring and dose adjustment. Conclusions: Treatment with encorafenib plus binimetinib met the primary endpoint criteria and demonstrated clinical benefit in patients with BRAFV600E-mutated thyroid cancer regardless of its histological type, such as DTC or ATC, with no new safety concerns identified. Encorafenib plus binimetinib could thus be a new treatment option for BRAF V600-mutated thyroid cancer. Clinical Trial Registration number: Japan Registry of Clinical Trials: jRCT2011200018.

Preferential B cell differentiation by combined immune checkpoint blockade for renal cell carcinoma is associated with clinical response and autoimmune reactions

Combined immune checkpoint blockade (ICB) is effective therapy for renal cell carcinoma (RCC). However, the dynamic changes in circulating B cells induced by combined ICB have not been clarified. The present study prospectively examined 22 patients scheduled to receive ICB for unresectable or metastatic RCC between March 2018 and August 2021. Eleven patients received combined therapy with anti-PD-1 (nivolumab) and anti-CTLA-4 (ipilimumab), and the other 11 patients received nivolumab monotherapy. Comprehensive phenotypes of circulating immune cells obtained prior to and after ICB therapy were analyzed by flow cytometry. Although the proportion of naïve B cells among total B cells was significantly decreased, that of switched memory B cells was significantly increased after combined therapy. In responders, the proportion of B cells among peripheral blood mononuclear cells was significantly higher prior to ICB therapy, and the proportion of switched memory B cells among total B cells tended to increase after ICB therapy. Of note, the proportion of plasmablasts among total B cells was significantly increased after ICB therapy in patients who developed severe immune-related adverse events (irAEs), and the proportion of B cells among peripheral blood decreased significantly. Furthermore, in four of five patients who developed immune-related hypophysitis following combined therapy, anti-pituitary antibody was detected in the serum. These results suggested that immune-related hypophysitis was closely related to the increase in circulating plasmablasts. Collectively, this study suggests that combined ICB promotes the differentiation of B cell populations, which is associated with efficient tumor suppression and development of irAEs.

Survival outcomes including salvage therapy of adult head and neck para-meningeal rhabdomyosarcoma: a multicenter retrospective study from Japan

BACKGROUND

Rhabdomyosarcoma is the most common soft tissue sarcoma in children, but rare in adults. Para-meningeal rhabdomyosarcoma in head and neck (PM-HNRMS) is less applicable for surgery due to the anatomic reason. PM-HNRMS has a poor prognosis in children. However, its clinical outcomes remain unclear in adults due to the rarity. Further, there is almost no detailed data about salvage therapy.

METHODS

We retrospectively examined the adult patients with PM-HNRMS treated at institutions belonging to the Kyushu Medical Oncology Group from 2009 to 2022. We evaluated the overall survival (OS) and progression-free survival (PFS) of the patients who received a first-line therapy. We also reviewed the clinical outcomes of patients who progressed against a first-line therapy and received salvage therapy.

RESULTS

Total 11 patients of PM-HNRMS received a first-line therapy. The characteristics were as follows: median age: 38 years (range 25 - 63 years), histology (alveolar/spindle): 10/1, and risk group (intermediate/high): 7/4. As a first-line therapy, VAC and ARST0431-based regimen was performed in 10 and 1 patients, respectively. During a first-line therapy, definitive radiation for all lesions were performed in seven patients. The median PFS was 14.2 months (95%CI: 6.0 - 25.8 months): 17.1 months (95%CI: 6.0 - not reached (NR)) for patients with stage I-III and 8.5 months (95%CI: 5.2 - 25.8 months) for patients with stage IV. The 1-year and 3-year PFS rates were 54.5% and 11.3% for all patients. Median OS in all patients was 40.8 months (95%CI: 12.1 months-NR): 40.8 months (95%CI: 12.1 - NR) for patients with stage I-III and NR for patients with stage IV. The 5-year OS rate was 48.5% for all patients. Among seven patients who received salvage therapy, three are still alive, two of whom remain disease-free for over 4 years after completion of the last therapy. Those two patients received multi-modal therapy including local therapy for all detected lesions.

CONCLUSION

The cure rate of adult PM-HNRMS is low in spite of a first-line therapy in this study. Salvage therapy might prolong the survival in patients who received the multi-modal therapy including local therapy for all detected lesions.

Early Phase Persistent Changes in the White Blood Cell Fraction in Patients With Advanced Urothelial Carcinoma Treated With Pembrolizumab: A Multicenter Retrospective Study

BACKGROUND/AIM

The association of clinical outcomes with posttreatment persistent changes in eosinophils and other white blood cell (WBC) subtypes in patients with advanced urothelial cancer (UC) treated with pembrolizumab after the failure of platinum-based chemotherapy is unclear.

PATIENTS AND METHODS

We retrospectively analyzed 87 patients with advanced UC who received pembrolizumab after the failure of platinum-based chemotherapy. The changes in WBC subtypes from pretreatment were evaluated three and six weeks after pembrolizumab administration. The association between the changes in the WBC subtypes and clinical outcomes was then evaluated using the Kaplan-Meier method and a Cox regression model.

RESULTS

Among WBC subtypes, significant changes in the absolute (AEC) and relative eosinophil count (REC) and the neutrophil-to-eosinophil ratio (NER) were observed at three and six weeks compared with pretreatment (p<0.001). Multivariable Cox regression analyses revealed that a persistent decrease in AEC and REC and a persistent increase in NER were associated with poor overall survival.

CONCLUSION

Persistent increase in AEC and REC and decrease in NER in the early phase after pembrolizumab may be significant early predictive markers of improved clinical outcomes in patients with advanced UC receiving pembrolizumab.

The Eosinophil Changes, Efficacy and Safety of Pembrolizumab in Advanced Urothelial Carcinoma Patients with an Older Age and a Poor Performance Status

Background

To evaluate the eosinophil changes, efficacy and safety of pembrolizumab treatment in advanced urothelial carcinoma patients of older age and those with a poor performance status (PS).

Materials and Methods

Consecutive patients with advanced UC who received pembrolizumab after the failure of platinum-based chemotherapy between January 2018 and June 2021 were retrospectively examined.

Results

105 patients (median age, 72 years), 71.4% of whom were men, were enrolled. Patients of ≥75 years of age were considered to be older patients (n=40), and patients with PS ≥2 were considered to have a poor PS (n=10). The objective response and disease control rates were 42.5% and 52.5%, respectively, in older patients and 0% and 10.0%, respectively, in patients with a poor PS. Overall survival (OS) in the older and younger groups did not differ to a statistically significant extent. However, a poor PS was significantly associated with poor survival. Safety analyses demonstrated no significant difference in the occurrence of any immune-related adverse events (irAEs), including grade ≥3, between the older and younger groups. However, a poor PS was significantly associated with the low occurrence of any irAEs. The change of the eosinophil count, the increase of the relative eosinophil count (REC) and the decrease of the neutrophil-to-eosinophil ratio (NER) did not differ to a statistically significant extent between the older and younger groups, but showed significant differences between the poor and good PS (PS 0–1) groups.

Conclusion

Pembrolizumab for advanced UC demonstrated similar changes in the eosinophil count, efficacy and toxicity in both older and younger patients. In patients with a poor PS, although toxicity was significantly lower, survival was significantly worse, and neither an increase in REC nor a decrease in NER were observed, but these values showed significant changes in patients with a good PS.

Electrophysiological characteristics and catheter ablation of atypical fast-slow atrioventricular nodal reentrant tachycardia using an inferolateral left atrial slow pathway

Background

Understandings of subtypes of atypical atrioventricular nodal reentrant tachycardia (AVNRT) using variants of slow pathway (SP) are still growing. Inferolateral (inf-lat-) left atrial (LA) SP is a rare variant extending into an inf-lat-LA along the mitral annulus (MA).

Purpose

To characterize an unknown subtype of atypical fast-slow (F/S-) AVNRT using an inf-lat-LA-SP as a retrograde limb (inf-lat-LA-F/S-AVNRT).

Methods

This Japanese multicenter retrospective study enrolled 4 patients of inf-lat-LA-F/S-AVNRT that was characterized by the earliest site of atrial activation during tachycardia (EAA) between 3 and 6 o'clock along the MA. The diagnosis was made by an exclusion of AV reentrant tachycardia (AVRT) and atrial tachycardia (AT) according to the standard criteria and was confirmed by successful elimination of tachycardia and the inf-lat-LA-SP.

Results

Surface ECG during tachycardia revealed long RP appearance except one who had short RP due to a short conduction time across the inf-lat-LA-SP. During tachycardia, far-field LA activation preceding near-field activation of coronary sinus (CS) musculature was visible in the CS recording in 2. Retrograde conduction via the inf-lat-LA-SP with a decremental delay was consistently reproducible with ventricular stimulation in 2, 1 of whom had double atrial response, while it was always masked by the presence of a retrograde conduction via the fast pathway in 1 and a retrograde block at the lower common pathway in 1. An injection of a small dose of ATP transiently interrupted a retrograde conduction over the inf-lat-LA-SP, suggesting its ATP-sensitivity. Exclusion of AVRT was made by no resetting of tachycardia with left ventricular extrastimulus in 2 and VA dissociation during overdrive pacing of tachycardia in remaining 2. Exclusion of AT was made by V-A-V response after ventricular entrainment in 1 and termination without atrial capture by ventricular pacing in 2. Ablation of the right-sided SP was unsuccessful to eliminate the tachycardia, but ablation at or near the EAA by transseptal approach was successful to cure the tachycardia, associated with an elimination of a retrograde conduction over the inf-lat-LA-SP following a development of an accelerated junction rhythm in all. Low-frequency potentials preceding local atrial activation, consistent with a retrograde activation via the inf-lat-LA-SP were detected along the MA medial to the EAA in 1.

Conclusions

Differential diagnosis of tachycardia with the EAA in the inf-lat-LA and especially long RP appearance should include inf-lat-LA-F/S-AVNRT. Presumed arrhythmogenic substrate of the inf-lat-LA-SP seemed to be consistent with the remnant of embryogenic AV ring tissue in the electropharmacological and locational characteristics. Successful elimination of this AVNRT can be obtained by ablation of the inf-lat-LA-SP, but not of the right-sided SP.

Funding Acknowledgement

Type of funding sources: None.

A multicentre retrospective study comparing site-specific treatment with empiric treatment for unfavourable subset of cancer of unknown primary site

BACKGROUND

Patients with cancer of unknown primary site are divided into two distinct groups, favourable and unfavourable subsets. For the unfavourable subset, empiric treatment or site-specific treatment is recommended, but limited knowledge exists about the efficacy of site-specific treatment compared with empiric treatment in clinical practice.

METHODS

In this multicentre retrospective study, we reviewed the medical records of patients with cancer of unknown primary site treated with chemotherapy (or chemoradiotherapy) as first-line treatment from eight institutions during 2006-18. We investigated the workup modality and categorized the patients into favourable and unfavourable subsets, which were further divided into site-specific and empiric treatment groups. Site-specific treatment is defined as a standard chemotherapy for an estimated primary site. We examined the efficacy in the favourable and unfavourable subsets and performed multivariable analysis for estimating the overall survival in the unfavourable subset.

RESULTS

Of 177 patients with cancer of unknown primary site, 33 and 144 were categorized into favourable and unfavourable subsets, respectively. In the unfavourable subset, 84 patients (58.3%) received empiric therapy, and 60 patients (41.7%) received site-specific treatment. Median overall survival was 10.0 and 10.1 months in site-specific and empiric treatment groups, respectively, with no significant difference (hazard ratio 1.01, 95% confidence interval 0.70-1.45, P = 0.95). Multivariable analysis revealed performance status, number of metastatic sites and hypoalbuminaemia as independent prognostic factors for overall survival in the unfavourable subset.

CONCLUSIONS

Overall survival in site-specific and empiric treatment groups was similar in the unfavourable cancer of unknown primary site subset in this study. Further research is needed to prolong overall survival in patients in the unfavourable cancer of unknown primary site subset.

Association Between Immune-Related Adverse Events and Efficacy and Changes in the Relative Eosinophil Count Among Patients with Advanced Urothelial Carcinoma Treated by Pembrolizumab

Background

To evaluate the association between immune-related adverse events (irAEs) and the clinical outcomes and also between irAEs and the post-treatment changes in the relative eosinophil count (REC) in advanced urothelial carcinoma (UC) patients treated with pembrolizumab.

Materials and Methods

This retrospective study analyzed 105 advanced UC patients treated with pembrolizumab after disease progression on platinum-based chemotherapy between January 2018 and June 2021. The association between the occurrence of irAEs and the efficacy of pembrolizumab was investigated. The change in the REC from before the initiation of pembrolizumab therapy, to three weeks after treatment and the incidence of irAEs were determined.

Results

Overall irAEs were associated with a significantly higher objective response rate (ORR) (58.8% vs 25.4%, P<0.001), a longer progression-free survival (PFS) (25.1 months vs 3.1 months, P< 0.001) and overall survival (OS) (31.2 months vs 11.5 months, P< 0.001) compared to patients without irAEs; however, grade ≥3 irAEs were not associated with the ORR (36.4% vs 36.2%, P=0.989), PFS (9.5 vs 5.5 months, P=0.249), or OS (not reached vs 13.7 months, P=0.335). Compared to a decreased REC at 3 weeks after pembrolizumab, an increased relative REC at 3 weeks was not associated with the incidence of any-grade irAEs (32.3% vs 32.5%, P=0.984) or of grade ≥3 irAEs (10.8% vs 10.0%, P=0.900). Multivariate analyses revealed a female sex (P=0.005), Eastern Cooperative Oncology Group Performance Status ≥1 (P=0.024), albumin <3.7 g/dl (P<0.001), decreased REC (3 weeks later) (P<0.001), and the absence of irAEs of any grade (P=0.002) to be independently associated with a worse OS.

Conclusion

Patients with irAEs showed a significantly better survival compared to patients without irAEs in advanced UC treated with pembrolizumab. An increased posttreatment REC may be a marker predicting improved clinical outcomes and it had no significant relationship with the incidence of irAEs.

The Association of Clinical Outcomes with Posttreatment Changes in the Relative Eosinophil Counts and Neutrophil-to-Eosinophil Ratio in Patients with Advanced Urothelial Carcinoma Treated with Pembrolizumab

Background

To evaluate the association of clinical outcomes with posttreatment changes in the relative eosinophil count (REC) and neutrophil-to-eosinophil ratio (NER) in patients with advanced urothelial cancer (UC) treated with pembrolizumab.

Materials and Methods

We retrospectively analyzed 105 patients with advanced UC who received pembrolizumab after the failure of platinum-based chemotherapy. The REC and NER before and three weeks after pembrolizumab were recorded. A receiver operating characteristic curve was used to determine the optimal cut-off values for analyzing the risk.

Results

There were no significant differences in the overall survival (OS) between the REC ≥4.8% and <4.8% groups and the NER ≥13.7 and <13.7 groups before pembrolizumab (p=0.997 and 0.669, respectively). However, a significant difference in the OS was confirmed between the increased and decreased REC groups and between the decreased and increased NER groups at 3 weeks after pembrolizumab (p<0.001 and 0.002, respectively). Multivariate analyses revealed that an Eastern Cooperative Oncology Group Performance Status ≥2 (P=0.003), albumin <3.7 g/dl (p=0.002), LDH >246 U/L (p=0.011), disease site ≥3 organs (p=0.019), decreased posttreatment REC (3 weeks later) (p=0.002) and increased posttreatment NER (3 weeks later) (p=0.022) were independent prognostic factors for a worse OS.

Conclusion

An increased REC and decreased NER after pembrolizumab may be significant early predictive markers of improved clinical outcomes in patients with advanced UC receiving pembrolizumab.

Fast-slow atrioventricular nodal reentrant tachycardia phenotype mimicking the slow-slow type

Background

Fast-slow (F/S-) atrioventricular (AV) nodal reentrant tachycardia (AVNRT) is characterized by a short atrio-His (AH) interval and the earliest site of atrial activation (EAA) in the proximal coronary sinus (EAA-CS), while slow-slow (S/S-) AVNRT presents a long AH interval and EAA-CS. Those intracardiac appearances are initial indicators for making a diagnosis.

Purpose

To identify an unknown phenotype of F/S-AVNRT.

Methods

Among 46 consecutive patients with F/S-AVNRT, 6 patients (1 man, age 59±9) had an apparent but not typical (pseudo-) S/S-AVNRT during an electrophysiologic study. In 2 patients, pseudo-S/S-AVNRT was clinically documented.

Results

In all 6 patients, the diagnosis of F/S-AVNRT was made by an exclusion of atrial tachycardia with findings of 1) a V-A-V response following ventricular entrainment or 2) termination without atrial capture by ventricular pacing, and an exclusion of AV reentrant tachycardia with a ventriculoatrial dissociation during an initial (so-called QRS transition) zone of ventricular entrainment. An initial A-A-V activation sequence on atrial induction of F/S-AVNRT observed in 1 patient and Wenckebach-type AV block during ongoing F/S-AVNRT developing in 3 patients suggested the presence of the lower common pathway (LCP). Like the typical S/S-AVNRT, pseudo-S/S-AVNRT was induced with atrial stimulation after a jump in the AH interval or double ventricular response. However, in all patients, the pseudo-S/S-AVNRT transited to F/S-AVNRT following AV block in a single cycle and/or pseudo-S/S-AVNRT transited from spontaneously or triggered by atrial contractions. Importantly, on these transitions, the atrial cycle length (CL) and EAA-CS remained unchanged, that is, the atrial CL of S/S-AVNRT was almost identical to that of F/S-AVNRT, suggesting that the essential circuit of both tachycardias was identical. Actually, both tachycardias were cured by ablation at a single site in the traditional slow pathway (SP). Collectively, the pseudo-S/S-AVNRT was diagnosed as another phenotype of F/S-AVNRT accompanied by sustained antegrade conduction via another bystander (likely the left-sided or superior) SP breaking through the His bundle owing to the repetitive antegrade block at the LCP occurring by linking phenomenon, thus representing a long AH interval during the ongoing F/S-AVNRT. When the antegrade conduction is blocked at the bystander SP during the pseudo-S/S-AVNRT, releasing the linking phenomenon, the subsequent antegrade conduction reach the His-bundle via the fast pathway, thus returning to F/S-AVNRT.

Conclusions

An unknown, but not rare F/S-AVNRT phenotype exists that apparently mimics the typical S/S-AVNRT and is also an unknown subtype of apparent S/S-AVNRT. The presence of this pseudo-S/S-AVNRT suggests the limitation of classifying types of AVNRT based on AH and HA intervals during tachycardia. Understandings of this phenotype can advance a diagnosis of atypical AVNRT with multiple phenotypes.

Funding Acknowledgement

Type of funding sources: None.

Clinical Outcomes of Mixed Response to Pembrolizumab in Advanced Urothelial Carcinoma After Platinum-based Chemotherapy

BACKGROUND/AIM

Despite the presence of a mixed response (MR) in patients with urothelial carcinoma (UC) who receive immune checkpoint inhibitors, the clinical outcome of these patient has not been reported. We evaluated the clinical outcome of MR to pembrolizumab for advanced UC.

PATIENTS AND METHODS

Advanced UC patients who received pembrolizumab after platinum-based chemotherapy failure with measurable disease in multiple organs were retrospectively analyzed.

RESULTS

Among 31 patients, MR [including progressive disease (PD)+complete response (CR) or partial response (PR)] was confirmed in 4 (12.9%). The median overall survival (OS) of the CR+PR (including CR+SD±PR), stable disease (SD), PD (including PD±SD) and MR groups was 16.0, 5.1, 5.4 and 4.3 months, respectively. There was no significant difference in the OS between the MR and CR+PR response groups (log-rank test, p=0.069).

CONCLUSION

A mixed response to pembrolizumab in advanced UC was not uncommon. Despite the non-significant difference in the OS between the mixed and CR+PR response groups, the OS of the MR group tended to be similar to that of the SD and PD response groups.

Multicenter prospective trial of total gastrectomy versus proximal gastrectomy for upper third cT1 gastric cancer

BACKGROUND

The appropriate surgical procedure for patients with upper third early gastric cancer is controversial. We compared total gastrectomy (TG) with proximal gastrectomy (PG) in this patient population.

METHODS

A multicenter, non-randomized trial was conducted, with patients treated with PG or TG. We compared short- and long-term outcomes between these procedures.

RESULTS

Between 2009 and 2014, we enrolled 254 patients from 22 institutions; data from 252 were included in the analysis. These 252 patients were assigned to either the PG (n = 159) or TG (n = 93) group. Percentage of body weight loss (%BWL) at 1 year after surgery, i.e., the primary endpoint, in the PG group was significantly less than that of the TG group (- 12.8% versus - 16.9%; p = 0.0001). For short-term outcomes, operation time was significantly shorter for PG than TG (252 min versus 303 min; p < 0.0001), but there were no group-dependent differences in blood loss and postoperative complications. For long-term outcomes, incidence of reflux esophagitis in the PG group was significantly higher than that of the TG group (14.5% versus 5.4%; p = 0.02), while there were no differences in the incidence of anastomotic stenosis between the two (5.7% versus 5.4%; p = 0.92). Overall patient survival rates were similar between the two groups (3-year survival rates: 96% versus 92% in the PG and TG groups, respectively; p = 0.49).

CONCLUSIONS

Patients who underwent PG were better able to control weight loss without worsening the prognosis, relative to those in the TG group. Optimization of a reconstruction method to reduce reflux in PG patients will be important.

Health guidance for prevention of lifestyle-related diseases using health-related mobile applications

Issue

Lifestyle modifications are essential for the prevention of lifestyle-related diseases such as hypertension, hyperlipidaemia, and type 2 diabetes. Healthcare providers in Japan are required to use information and communications technologies (ICT), such as health-related mobile applications (mHealth apps), in health guidance.

Description of the Problem

To understand the results of and issues in health guidance, two searches were conducted to identify the domains of health guidance provided using ICT. We searched the PubMed and Japan Medical Abstracts Society databases to identify articles published from 2000-2018. The first search identified frameworks of health guidance provided using ICT. The second search identified primary studies about using mHealth apps published between 2000 and 2018. The sample comprised 22 unique programs from 38 primary studies. The following research questions were explored: 1) What is the purpose of using the mHealth app?

2) Is there a significant difference in the effect of using the mHealth app instead of face-to-face communication?

Results

The mHealth app was used to enhance convenience and to improve or modify lifestyle. The latter included self-monitoring, typing health information, providing knowledge, sharing information, providing encouragement and praise, and correction of action plans. Some positive effects were observed, including compensating for insufficient information, enhancing self-management, and improving degrees of satisfaction of users. Only two programs did not report a significant difference in the effect of using the mHealth app as compared to face-to-face communication.

Lessons

This review showed that the frequency of typing information about diet and exercise appeared to be related to the prevention of primary lifestyle-related diseases and the improvement of self-management behaviour.

Key messages

Use of the mHealth app for providing health guidance might enhance continuous support for self-monitoring and self-management behaviour. Use the mHealth app for providing encouragement and praise might promote a smooth conversation, which in turn would facilitate appropriate self-management behaviour.

OX40 and LAG3 are associated with better prognosis in advanced gastric cancer patients treated with anti-programmed death-1 antibody

Background

Anti-PD-1 monoclonal antibody, nivolumab, has shown efficacy for advanced gastric cancer (AGC). However, the specific immune cell subsets predominantly activated during the period of anti-PD-1 therapy for AGC have not been clarified.

Methods

Peripheral blood of 30 AGC patients treated with nivolumab was prospectively obtained before the initial and second administrations and at the time of progressive disease (PD). The proportions of immune cell subsets and the serum concentrations of cytokines were systematically analysed by flow cytometry. Associations of subsets and serum cytokines with therapeutic effects were evaluated.

Results

After the initial administration, significant increases in activated central/effector memory, activated effector T cells, and activated T-helper 1 subsets were observed. At the time of PD, activated regulatory T cells, LAG3-positive CD4+/CD8+ T cells, and TIM3-positive CD4+/CD8+ T cells increased significantly. Significant positive correlations were shown between progression-free survival and proportions of LAG3-positive CD4+/CD8+ T cells and of OX40-positive CD4+/CD8+ T cells (log-rank p = 0.0008, 0.0003, 0.0035 and 0.0040).

Conclusions

Nivolumab therapy enhances activation of central/effector memory and effector subsets of CD4+/CD8+ T cells. The expression levels of LAG-3 and OX40 on T cells correlated with the efficacy of nivolumab therapy and could be reasonable biomarkers for anti-PD-1 therapy.

Activation of memory/effector T cells and association between prognosis and OX40-positive T cells in advanced head and neck cancer patients treated with anti-programmed death-1 antibody

35

Background: Anti-programmed death-1 (PD-1) monoclonal antibody, nivolumab, enhances anti-tumor activity by inhibiting the interaction of PD-1 and programmed death-1 ligand 1 and has shown efficacy for platinum-refractory recurrent or advanced head and neck cancer (HNC). However, subsets of immune cells predominantly activated during the period of anti-PD-1 therapy for HNC and specifically associated with the prognosis have not been clarified. Methods: Peripheral blood mononuclear cells of 15 HNC patients treated with nivolumab were prospectively obtained before the initial and second administrations of nivolumab, and at the time of progressive disease (PD). We performed comprehensive analysis of the proportion of immune cell subsets by flow cytometry, including the expression of coinhibitory and costimulatory molecules such as T-cell immunoglobulin and mucin domain 3 (TIM-3), lymphocyte-activation gene 3 (LAG-3), T-cell immunoreceptor with Ig and ITIM domains (TIGIT), B and T lymphocyte attenuator (BTLA), CD28, OX40, inducible T cell costimulator (ICOS). Association between changes in the proportion of the subsets and therapeutic effect were also analyzed. Results: Median progression free survival (PFS) of the whole patients was 96 days (95% CI 70–308). After a single course of nivolumab, patients showed a significant increase in activated central memory and effector subsets of CD4+/CD8+ T cells and activated helper T1 cells (p = 0.0039, 0.0078, 0.0273, 0.0391, 0.0391). A trend of increase of activated effector memory CD4+/CD8+ T cell was observed (p = 0.4961, 0.3594). At the time of PD, effector regulatory T cells, LAG3 positive CD4+/CD8+ T cells, TIM-3 positive CD4+/CD8 T cells and BTLA positive CD4+/CD8+ T cells significantly increased. Significant positive correlations were found between PFS and the proportion of OX40 positive CD4+/CD8+ T cells before nivolumab therapy (p = 0.0239, 0.0134). Conclusions: Nivolumab therapy enhances activation of central memory and effector subsets of CD4+/CD8+ T cells. The expression level of OX40 on T cells was correlated with efficacy of nivolumab therapy in HNC patients.

Effects of mirogabalin, a novel ligand for the α₂δ subunit of voltage-gated calcium channels, on N-type calcium channel currents of rat dorsal root ganglion culture neurons

Mirogabalin, which is a novel ligand for the α₂δ subunit of voltage-gated calcium channels, is being developed for treating neuropathic pain including diabetic peripheral neuropathy and postherpetic neuralgia. Mirogabalin possesses unique α₂δ subunit binding characteristics and has potent and long-lasting analgesic effects in neuropathic pain models. In the present study, we investigated the effects of mirogabalin on N-type calcium channel currents of the rat dorsal root ganglion (DRG) culture neurons using the whole-cell patch clamp technique. Small or medium DRG neurons were isolated from Sprague-Dawley rats and were incubated for 20 to 24 h with mirogabalin or pregabalin. The DRG neurons were depolarised from a holding potential of -40 mV to +40 mV in steps of 10 mV for 220 ms, and elicited N-type calcium channel currents were recorded. The N-type calcium channel currents were verified by sensitivity to ω-conotoxin GVIA, a selective N-type calcium channel blocker. Mirogabalin inhibited the calcium channel currents of rat DRG neurons at 50 μM, and pregabalin inhibited them at 200 μM. Mirogabalin and pregabalin showed significant differences in the peak current densities at depolarisation to -20 and -10 mV when compared with that shown by the vehicle control. In conclusion, mirogabalin inhibits N-type calcium channel currents in rat DRG culture neurons. The potent and long-lasting analgesic effects of mirogabalin are thought to be associated with its potent and selective binding to α₂δ-1 subunits and following functional inhibition of calcium channel currents.

Epithelial-mesenchymal transition is activated in CD44-positive malignant ascites tumor cells of gastrointestinal cancer

Disseminated cancer cells in malignant ascites possess unique properties that differ from primary tumors. However, the biological features of ascites tumor cells (ATC) have not been fully investigated. By analyzing ascites fluid from 65 gastrointestinal cancer patients, the distinguishing characteristics of ATC were identified. High frequency of CD44⁺ cells was observed in ATC using flow cytometry (n = 48). Multiplex quantitative PCR (n = 15) showed higher gene expression of epithelial‐mesenchymal transition (EMT)‐related genes and transforming growth factor beta (TGF‐beta)‐related genes in ATC than in the primary tissues. Immunohistochemistry (n = 10) showed that ATC also had much higher expression of phosphorylated SMAD2 than that in the corresponding primary tissues. TGF‐beta 1 was detected in all cases of malignant ascites by enzyme‐linked immunoassay (n = 38), suggesting the possible interaction of ATC and the ascites microenvironment. In vitro experiments revealed that these ATC properties were maintained by TGF‐beta 1 in cultured ATC(n = 3). Here, we showed that ATCrevealed high frequencies of CD44 and possessed distinct EMT features from primary tissues that were mainly maintained by TGF‐beta 1 in the ascites.

First-line chemotherapy with S-1 alone or S-1 plus cisplatin for elderly patients with advanced gastric cancer: a multicenter propensity score matched study

BACKGROUND

Fluoropyrimidine and platinum combination is the standard treatment for advanced or recurrent gastric cancer (AGC). However, fluoropyrimidine monotherapy is commonly used for elderly patients with AGC because of its good tolerability.

METHODS

In this multicenter retrospective study, we collected clinical data of AGC patients aged 70 years or older, treated with S-1 alone or S-1 plus cisplatin (SP) as the first-line treatment between January 2009 and December 2011. Propensity score matched cohorts (PSMC) were used for reducing the confounding effects to compare efficacy and safety between the two treatment groups. Cox regression analysis was performed to clarify the prognostic factors.

RESULTS

PSMC (n = 109 in each group) were selected from among 444 eligible patients (S-1 group, 210; SP group, 234); the S-1 group included more patients deemed unfit for intensive chemotherapy than the SP group (e.g., higher age, poorer PS, poor renal function). In the PSMC, patients' characteristics were comparable between groups, except the male ratio (S-1 group, 64.2%; SP group, 77.1%; p = 0.04). No significant differences were observed in either overall survival [hazard ratio (HR) 0.93, p = 0.63] or progression-free survival (HR 1.09, p = 0.61). Severe adverse events (AEs) and hospitalization due to AEs were more frequent in the SP group than in the S-1 group (p < 0.001 each).

CONCLUSION

Our findings do not support the survival benefit of SP over S-1 in elderly patients with AGC. We are now conducting a prospective comparative study to optimize treatment strategy and explore applicability of the geriatric assessment for these patients.

The risk factors for oxaliplatin-induced peripheral sensory neuropathy and thrombocytopenia in advanced gastric cancer

PURPOSE

Peripheral sensory neuropathy (PSN) and thrombocytopenia are the main dose-limiting toxicities of oxaliplatin for the treatment of advanced gastric cancer (AGC). Because the risk factors for those toxicities in practice have not been clarified, we conducted this prospective study.

METHODS

AGC patients who received oxaliplatin-based therapy at any of seven institutions participating in the Kyushu Medical Oncology Group were assessed after we obtained written informed consent.

RESULTS

A total of 60 patients including 39 males and 21 females were examined. The median age was 66 years. The numbers of patients receiving oxaliplatin as the first, second, or third and later lines of therapy were 39, 16, and 5, respectively. An initial dose of 130, 100, or < 100 mg/m² oxaliplatin was administered to 12, 39, and 9 patients, respectively. S-1 or capecitabine as a concomitant drug was administered in 54 and 6 patients, respectively. In multivariate analysis, the comorbidity of diabetes mellitus was associated with ≥ grade 2 thrombocytopenia (p = 0.035). No significant risk factor was associated with ≥ grade 2 PSN. However, the accumulated dose of oxaliplatin exhibited a strong correlation with ≥ grade 2 PSN (p = 0.0043), and the predicted accumulated dose of oxaliplatin in which 10% of patients developed ≥ grade 2 PSN was 800 mg/m². The frequency of PSN in subsequent paclitaxel therapy in patients with ≥ grade 2 or worse PSN in oxaliplatin-based chemotherapy did not increase compared to those with none or grade 1 PSN in oxaliplatin.

CONCLUSION

Thrombocytopenia in AGC patients with diabetes mellitus should be carefully monitored during oxaliplatin-based therapy.

Three-dimensional shaping technique for coil placement using the steam-shaped microcatheter for ruptured blood blister-like aneurysm

Treatment of blood blister-like aneurysm (BBA) is a challenge due to its unfavourable morphology, small size and the friable neck of BBA. In the management of ruptured BBA, coil placement can be achieved by stent-assisted coil embolisation. We propose to incorporate a new technique using a steam-shaped microcatheter to improve safety. A 59-year-old woman was transferred to our hospital and diagnosed with subarachnoid haemorrhage (SAH) due to a ruptured BBA of the left internal carotid artery (ICA) at the C2 portion. For coil embolisation, we selected the aneurysm sac using a three-dimensional shaping technique and the jailing method. Post-embolisation angiography revealed complete occlusion of the aneurysmal sac. For safe treatment and stability of BBA, the shape of the catheter tip and the distal portion of the microcatheter are two important factors to consider. The proposed technique could help resolve the problem of catheter shaping in the treatment of BBA.

A phase 2 study of fosaprepitant combined with high-dose dexamethasone for Japanese cancer patients receiving highly emetogenic chemotherapy

PURPOSE

Combination therapy of fosaprepitant, dexamethasone (DEX) and a serotonin (5-HT3) receptor antagonist is a standard antiemetic prophylaxis for patients receiving highly emetogenic chemotherapy (HEC). However, the appropriate dose of DEX has not been established in Japan. This study determined the efficacy and safety of triplet antiemetic prophylaxis in Japanese patients receiving HEC when administered the same doses of DEX as those given in a previous international phase 3 study on this drug.

METHODS

To assess the efficacy and safety of a sufficient dose of DEX (12 mg on day 1, 8 mg on day 2, 16 mg on days 3 and 4) in combination with intravenous fosaprepitant and granisetron, we prospectively examined patients receiving HEC including cisplatin (≥50 mg/m). The primary endpoint was to determine the percentage of patients who had achieved a complete response (CR), which was defined as no vomiting and no rescue therapy during the entire treatment course.

RESULTS

Between February 2013 and January 2015, 44 patients were enrolled with a median age of 65 years (range, 30-75). There were 34 males (77.3%) in the study. Most of the patients had upper gastrointestinal cancers. The CR rate during the treatment course was 70% (95% confidence interval [CI]: 55%-83%) in the overall phase and 91% (95% CI: 78%-97%) in the acute phase and 70% (95% CI: 55%-83%) in the delayed phase. Appreciable severe toxicities related to the antiemetic therapy were not observed.

CONCLUSIONS

These results suggest that a sufficient dose of DEX in combination with fosaprepitant and granisetron is optimal as an antiemetic prophylaxis for Japanese patients receiving HEC.

E‑cadherin regulates proliferation of colorectal cancer stem cells through NANOG

Cancer stem cells (CSCs) possess a self-renewal ability and display tumorigenic potential in immunodeficient mice. Colorectal CSCs are thought to be a uniform population and no functionally distinct subpopulations have been identified. Because E-cadherin is an essential molecule for self-renewal of embryonic stem cells, we examined E-cadherin expression, which may play a role in maintaining the properties of CSCs, in EpCAM^high/CD44⁺ colorectal CSCs from human primary colorectal cancers. We obtained 18 surgical specimens of human primary colorectal cancer. CD44, EpCAM, and E-cadherin expression were analyzed by fluorescence-activated cell sorting. Sorted EpCAM^high/CD44⁺ colorectal CSCs were injected into immunodeficient mice to estimate the tumorigenic potential. Genetic profiles were analyzed by cDNA microarray. Notably, colorectal CSCs could be divided into two populations based on the E-cadherin expression status, and they exhibited different pathological characteristics. Compared to E-cadherin-negative colorectal CSCs, E-cadherin-positive (EC⁺) colorectal CSCs demonstrated higher tumor growth potential in vivo. EC⁺ colorectal CSCs revealed a higher expression of the pluripotency factor NANOG, which contributed to the higher tumor growth potential of EC⁺ colorectal CSCs through control of cyclin D1 expression. These findings are the first demonstration of functionally distinct subpopulations of colorectal CSCs in human clinical samples.

Functional characterization of recombinant snake venom rhodocytin: rhodocytin mutant blocks CLEC-2/podoplanin-dependent platelet aggregation and lung metastasis

Essentials We generated recombinant rhodocytin that could aggregate platelets via CLEC-2. Recombinant wild-type rhodocytin formed heterooctamer with four α- and β-subunits. Asp 4 in α-subunit of rhodocytin was required for binding to CLEC-2. Inhibitory mutant of rhodocytin blocked podoplanin-dependent hematogenous metastasis.

SUMMARY

Background Rhodocytin, a disulfide-linked heterodimeric C-type lectin from Calloselasma rhodostoma consisting of α-subunits and β-subunits, induces platelet aggregation through C-type lectin-like receptor 2 (CLEC-2). CLEC-2 is a physiological binding partner of podoplanin (PDPN), which is expressed on some tumor cell types, and is involved in tumor cell-induced platelet aggregation and tumor metastasis. Thus, modified rhodocytin may be a possible source of anti-CLEC-2 drugs for both antiplatelet and antimetastasis therapy. However, its molecular function has not been well characterized, because of the lack of recombinant rhodocytin that induces platelet aggregation. Objective To produce recombinant rhodocytin, in order to verify its function with mutagenesis, and to develop an anti-CLEC-2 drug based on the findings. Methods We used Chinese hamster ovary cells to express recombinant rhodocytin (wild-type [WT] and mutant), which was analyzed for induction/inhibition of platelet aggregation with light transmission aggregometry, the formation of multimers with blue native PAGE, and binding to CLEC-2 with flow cytometry. Finally, we investigated whether mutant rhodocytin could suppress PDPN-induced metastasis in an experimental lung metastasis mouse model. Results Functional WT] rhodocytin (αWTβWT) was obtained by coexpression of both subunits. Asp4 in α-subunits of rhodocytin was required for CLEC-2 binding. αWTβWT formed a heterooctamer similarly to native rhodocytin. Moreover, an inhibitory mutant of rhodocytin (αWTβK53A/R56A), forming a heterotetramer, bound to CLEC-2 without inducing platelet aggregation, and blocked CLEC-2-PDPN interaction-dependent platelet aggregation and experimental lung metastasis. Conclusion These findings provide molecular characterization information on rhodocytin, and suggest that mutant rhodocytin could be used as a therapeutic agent to target CLEC-2.

Optimisation of antithrombin resistance assay as a practical clinical laboratory test: Development of prothrombin activator using factors Xa/Va and automation of assay

INTRODUCTION

Antithrombin resistance (ATR) is a novel thrombotic risk in abnormal prothrombins. A manual ATR assay using Oxyuranus scutellatus (Ox) venom as a prothrombin activator was established for detecting antithrombin-resistant prothrombin. However, this assay was limited because of Ox snake venom availability and its throughput capacity. Here, we have improved the ATR assay using bovine factors Xa and Va (FXa/Va) as prothrombin activators and have optimised assay conditions for an automated instrument (ACL TOP 500).

METHODS

Diluted plasma was incubated with a prothrombin activator mix (phospholipids, CaCl₂ , and bovine FXa/Va), followed by inactivation with antithrombin for 10, 20 and 30 minutes. We added a chromogenic substrate S-2238, and assessed changes in absorbance/min at 405 nm. We also adapted assay conditions for ACL TOP 500.

RESULTS

Optimum conditions for FXa/Va treatment were 6.25% phospholipids, 5 mM CaCL₂ , 0.01 μg/mL FXa and 0.1 μg/mL FVa. ATR assay kinetics with the FXa/Va activator was comparable with that with the Ox activator in heterozygous reconstituted plasma with the recombinant wild-type or antithrombin-resistant prothrombin. Using ACL TOP 500, optimum conditions for the FXa/Va treatment were 10.0% phospholipids, 5 mM CaCl₂ , 0.02 μg/mL FXa and 0.2 μg/mL FVa. The automated ATR assay with the FXa/Va activator demonstrated good detectability for antithrombin-resistant prothrombin in plasma from a heterozygous carrier with prothrombin Yukuhashi or Belgrade.

CONCLUSION

We optimised the ATR assay with the FXa/Va activator and adapted the assay for ACL TOP 500; the assay showed the ability to clearly detect antithrombin-resistant prothrombin in manual and automated procedures.

Retrospective analysis of cardiovascular diseases related to chemotherapies for advanced solid tumor patients

Appropriate management of cardiovascular diseases (CVDs) related to chemotherapy for solid tumors is important for safe oncologic treatment. However, prediction of the onset and progression of CVDs has not generally been established in Japan. We carried out a retrospective analysis of advanced or recurrent solid tumor patients who received chemotherapies in a single institution. Patient characteristics, chemotherapy regimens, adverse events, CVDs before chemotherapy, and diagnosis of CVDs in association with chemotherapy were assessed. During the period from April 2006 to March 2012, 394 patients were examined. Cardiac diseases (CDs), hypertension (HT), or arterial thrombosis or venous thromboembolism were prevalent in 37 (9.4%), 22 (5.6%), five (1.3%), and 14 (3.5%) cases, respectively. HT (14.5%) and venous thrombosis (5.8%) were frequent in patients who received bevacizumab-containing chemotherapy. Four cases with left ventricular dysfunction experienced a decrease of ejection fraction and early filling/atrial filling (E/A) and E/A tended to decrease before ejection fraction. Ninety (62.1%) of 145 cases showed an increase in the D-dimer (DD) level before chemotherapy, and a further increase in DD level was found when venous thrombosis occurred. Relative risks of the disease progression of HT, CD, and thromboembolism because of chemotherapy were 1.3, 1.9, and 3.6, respectively. A decrease in E/A and an increase in DD were suggested to be valuable for early diagnosis of the respective onsets of left ventricular dysfunction and venous thrombosis related to chemotherapy. We conclude that patients with previous CD tend to have disease progression of CD during chemotherapy.

C-type lectin-like receptor 2 promotes hematogenous tumor metastasis and prothrombotic state in tumor-bearing mice

Essentials The role of C-type lectin-like receptor-2 (CLEC-2) in cancer progression is unclear. CLEC-2-depleted mouse model is generated by using a rat anti-mouse CLEC-2 monoclonal antibody. CLEC-2 depletion inhibits hematogenous tumor metastasis of podoplanin-expressing B16F10 cells. CLEC-2 depletion prolongs cancer survival by suppressing thrombosis and inflammation.

SUMMARY

Background C-type lectin-like receptor 2 (CLEC-2) is a platelet activation receptor of sialoglycoprotein podoplanin, which is expressed on the surface of certain types of tumor cells. CLEC-2-podoplanin interactions facilitate hematogenous tumor metastasis. However, direct evidence of the role of CLEC-2 in hematogenous metastasis and cancer progression is lacking. Objective and methods We generated immunological CLEC-2-depleted mice by using anti-mouse CLEC-2 monoclonal antibody 2A2B10 and investigated whether CLEC-2 promoted hematogenous tumor metastasis and tumor growth and exacerbated the prognosis of mice bearing podoplanin-expressing B16F10 melanoma cells. Results Our results showed that hematogenous metastasis was significantly inhibited in CLEC-2-depleted mice. B16F10 cells co-cultured with wild-type platelets, but not with CLEC-2-deficient platelets, showed increased proliferation. However, B16F10 cell proliferation was not inhibited in CLEC-2-depleted mice. Histological analysis showed that thrombus formation in tumor vessels was significantly inhibited and functional vessel density was significantly increased in CLEC-2-depleted mice. These data suggest that CLEC-2 deficiency may inhibit thrombus formation in tumor vessels and increase the density of functional vessels, thus improving oxygen and nutrient supply to tumors, indirectly promoting tumor proliferation. Furthermore, the overall survival of CLEC-2-depleted mice was significantly prolonged, which may be due to the suppression of thrombus formation in the lungs and subsequent inhibition of systemic inflammation and cachexia. Conclusions These data provide a rationale for the targeted inhibition of CLEC-2 as a new strategy for preventing hematogenous tumor metastasis and for inhibiting cancer-related thromboembolism.

Multicenter randomized phase II study of cisplatin and fluorouracil plus docetaxel (DCF) compared with cisplatin and fluorouracil plus Adriamycin (ACF) as preoperative chemotherapy for resectable esophageal squamous cell carcinoma (OGSG1003)

BACKGROUND

This phase II trial evaluated the efficacy of cisplatin and fluorouracil (CF)-based combination neoadjuvant chemotherapy on the outcome of patients with resectable locally advanced esophageal squamous cell carcinoma (ESCC). We compared the recurrence-free survival (RFS) associated with CF plus Adriamycin (ACF) with that associated with CF plus docetaxel (DCF) to select an alternative regimen in a new phase III trial investigating the optimal neoadjuvant treatment of patients with ESCC.

PATIENTS AND METHODS

Patients with resectable advanced ESCC were randomly assigned to either ACF (Adriamycin 35 mg/m2, cisplatin 70 mg/m2 i.v. on day 1, fluorouracil 700 mg/m2 continuous infusion for 7 days) every 4 weeks or DCF (docetaxel 70 mg/m2, cisplatin 70 mg/m2 i.v. on day 1, fluorouracil 700 mg/m2 continuous infusion for 5 days) every 3 weeks. Surgery was scheduled after completion of two cycles of chemotherapy. The primary end point was RFS, analyzed by the intention-to-treat.

RESULTS

Between October 2011 and October 2013, 162 patients at 10 institutions were enrolled in the study, all of whom were eligible and randomly assigned to the two groups (81 to the ACF group and 81 to the DCF group). The R0 resection rates for the ACF and DCF groups were equivalent (95.9% versus 96.2%, P = 0.93). The 2-year RFS and overall survival rates for DCF versus ACF were 64.1% versus 42.9% (hazard ratio 0.53, 95% confidence interval 0.33-0.83, P = 0.0057) and 78.6% versus 65.4% (P = 0.08), respectively.

CONCLUSION

Compared with ACF, DCF chemotherapy was associated with prolonged RFS for patients with resectable advanced ESCC. Thus, DCF chemotherapy has potential as a standard neoadjuvant therapy for resectable ESCC.

CLINICAL TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trials Registry of Japan (identification number UMIN000004555/000004616).

Efficacy and Safety of TAS-102 in Clinical Practice of Salvage Chemotherapy for Metastatic Colorectal Cancer

BACKGROUND

TAS-102 is an anti-metabolite which demonstrated activity against multidrug-resistant advanced colorectal cancer. Its major toxicities are hematological disorders.

PATIENTS AND METHODS

Background, TAS-102 efficacy, toxicities and outcomes for patients with multidrug-resistant advanced colorectal cancer from six Institutions of the Kyushu Medical Oncology Group were retrospectively surveyed.

RESULTS

Forty-three patients, including fragile patients due to declining performance status and other comorbidities (37%) were analyzed. Efficacy was reflected in an objective overall response of 3%, median progression-free survival of 74 days (2.5 months) and median overall survival of 229 days (7.6 months). The most frequent Common Terminology Criteria for Adverse Events grade 3/4 adverse events were neutropenia (44%), leukopenia (26%) and anemia (23%). Febrile neutropenia was found in 7%. Sub-group analysis demonstrated an improved outcome on treatment with the sequence regorafenib-TAS-102.

CONCLUSION

TAS-102 was safely administered to modestly fragile patients with equivalent efficacy to that for the non-fragile population. Further investigation of sequential treatment using regorafenib and TAS-102 is needed.

Intraluminal superior vena cava metastasis from adenosquamous carcinoma of the duodenum: A case report

In 2013, a 76-year-old male with a cardiac pacemaker was diagnosed with adenosquamous carcinoma of the duodenum. Subsequently, a pancreatoduodenectomy and lymph node dissection were performed, and 12 cycles of adjuvant chemotherapy (modified FOLFOX6 regimen), which consisted of fluorouracil, leucovorin and oxaliplatin, were administered via a central venous catheter. At 5 months after the completion of adjuvant chemotherapy, the patient experienced the sudden onset of severe pain at the back right of the ear, edema of the right side of the face and right jugular vein dilatation. Computed tomography (CT) revealed filling defects in the superior vena cava (SVC) and right brachiocephalic vein, indicating catheter-induced venous thrombosis. Although the catheter was removed and anti-coagulation therapy, aspiration of the thrombosis and ballooning dilatation were performed immediately, the patient's symptoms were not ameliorated. Notably, histological examination following thrombus aspiration revealed metastatic cancer cells, and fluorodeoxyglucose-positron emission tomography/CT identified metabolically active nodules in the SVC at locations consistent with the initial duodenal tumors detected by CT and in the first thoracic vertebrae. The tumor thrombus rapidly increased in size and resulted in worsening dyspnea. Subsequently, radiotherapy was performed, followed by chemotherapy, which relieved the systemic symptoms and suppressed the tumor growth. Adenosquamous carcinoma of the duodenum is extremely rare, and to the best of our knowledge, intraluminal SVC metastasis as a result of adenosquamous carcinoma of the duodenum has not been reported previously. The placement of a cardiac pacemaker, central venous catheter and tumor cells possessing high metastatic potential are hypothesized to have contributed to this rare case of metastasis.

Abstract 1520: Plasticity of CD44+ colorectal cancer stem cells depends on TGF-beta-induced epithelial mesenchymal transition (EMT): evidences from ex vivo culture system

Background

EpCAMhigh CD44+ colorectal cancer (CRC) cells are thought to be cancer stem cells. Recently CD44- CRC cells are also suggested to acquire a character of cancer stem cells, but the molecular mechanisms have not been clarified. Epithelial-mesenchymal transition (EMT) is a possible process of cancer cells to acquire stemness. However, it is unclear whether EMT can be induced in primary human CRC.

Patients and Methods

We obtained surgical specimens from 51 CRC patients, and cultured isolated cancer cells on matrigel-coated dish with medium containing several growth factors. For induction of EMT, TGF-beta was added into the culture medium. Immunocytochemistry staining, flow cytometric analysis of the spheroid cells and single cell PCR analysis using 48-gene set containing and Embryonic stem cell (ES)-related genes EMT-related genes were performed.

Results

Cancer cells proliferated and formed sphere (&gt;50 μm in diameter) in 15 out of 51 samples after one week culture. The sphere-forming ability was related with clinical stage (Stage1 and 2:16.7% Stage 3 and 4:41.3%). Sorted single CD44+ cell had higher sphere-forming ability, compared to CD44- cell. The higher expression of ES- and EMT-related genes was observed in sphere-forming cells than in non-sphere forming cells. To confirm the heterogeneity of sphere forming cells derived from sorted single cell, we performed single cell PCR using C1 single cell auto prep system. Cells consisted of a sphere were classified into 2 different population on the basis of primary component analysis. In addition, flow cytometric analysis revealed that sphere forming CD44+ cells gave rise to CD44- cells. These results suggest that CD44+ cells have an ability to reconstruct the heterogeneous population. Next we isolated sphere-forming cells and cultured on the same condition. Isolated sphere-forming CD44+ cells could form sphere with high efficiency. This result suggests that CD44+ cell have a self-renewal ability. Previously, it has been reported that EMT was induced after TGF-beta treatment in cancer cell lines and these cells acquired cancer stem cell properties. In our culture system, we could detect very few CD44+ cells after 8-days culture of CD44- cells, and TGF-beta treatment also increased the number of CD44+ cells. These CD44 expressing cells expressed N-cadherin. Furthermore N-cadherin expressing cells expressed ES-and EMT-related genes. At last, TGF-beta enhanced sphere-forming ability in CD44- cells.

Conclusions

To our knowledge, this is the first report that CD44- cells from primary CRC samples undergo EMT and induced CD44+ cells by TGF-beta treatment. Investigation whether these induced CD44+ cells have cancer stem cell like properties such as tumorigenic potential in immunosuppressive mouse is underway. Also we are going to identify cancer stem cell specific gene expression in our culture system using DNA microarray.

Citation Format: Michitaka Nakano, Hioshi Ariyama, Shingo Tamura, Taichi Isobe, Kohta Miyawaki, Yuta Okumura, Hitoshi Kusaba, Takashi Ueki, Eishi Baba, Koichi Akashi. Plasticity of CD44+ colorectal cancer stem cells depends on TGF-beta-induced epithelial mesenchymal transition (EMT): evidences from ex vivo culture system. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1520. doi:10.1158/1538-7445.AM2015-1520