Mariko Ogura

Circulating tumor cells as a surrogate marker for determining response to chemotherapy in patients with advanced gastric cancer

The purpose of this study was to quantify circulating tumor cells (CTCs) in advanced gastric cancer (AGC) patients, and to demonstrate the role of CTCs in cancer therapy. This study investigates the hypothesis that CTCs can predict clinical outcomes in patients with AGC. From November 2007 to June 2009, 52 patients with AGC were enrolled into a prospective study. The chemotherapy regimen was an S‐1‐based regimen (S‐1 with or without cisplatin) or paclitaxel. CTCs of whole blood at baseline, 2 weeks, and 4 weeks after initiation of chemotherapy, were isolated and enumerated using immunomagnetics. Patients with ≥4 CTCs at 2‐week points and 4‐week points had a shorter median progression‐free survival (PFS) (1.4, 1.4 months, respectively) than those with the median PFS of <4 CTCs (4.9, 5.0 months, respectively) (log‐rank test; P < 0.001, P < 0.001, respectively). Patients with ≥4 CTCs at 2‐week points and 4‐week points had shorter median overall survival (OS) (3.5, 4.0 months, respectively) than those with the median PFS of <4 CTCs (11.7, 11.4 months, respectively) (log‐rank test; P < 0.001, P = 0.001, respectively). In conclusion, this study demonstrates that CTC measurement may be useful as a surrogate marker for determining response to S‐1‐based or paclitaxel regimens in AGC.

Phase II study of reintroduction of oxaliplatin for advanced colorectal cancer in patients previously treated with oxaliplatin and irinotecan: RE-OPEN study

Background The effectiveness of reintroducing oxaliplatin in patients with metastatic colorectal cancer refractory to standard chemotherapy has not been verified. We performed a single-arm, open-label, Phase II study to evaluate the safety and efficacy of reintroducing oxaliplatin. Methods Eligible patients had received prior chemotherapy including oxaliplatin and irinotecan that achieved a response or stable disease followed by confirmed disease progression ≥6 months previously during prior oxaliplatin-based therapy. The primary endpoint was the disease control rate (DCR) after 12 weeks of treatment starting. The DCR was defined as the sum of patients with complete response, partial response, and stable disease. Results Thirty-three patients were enrolled. The median age was 62 (range: 35–77) years and the male/female ratio was 19/14. Eastern Cooperative Oncology Group performance status was 0 in 84.8%. Fourteen primary tumors were in the colon and 19 were in the rectum. All patients received modified FOLFOX6 as the protocol treatment. After 12 weeks of treatment starting, the DCR was 39.4% (95% confidence interval 21.8–57.0) and the response rate (complete response and partial response) was 6.1%. The median number of chemotherapy cycles was five and the median total dose of oxaliplatin was 425 mg/m2. Median progression-free survival time was 98 days and median overall survival was 300 days. The incidence of grade ≥1 and grade ≥3 allergic reactions was 28.1% and 3.1%, respectively. The incidence of grade ≥1 and grade ≥3 peripheral sensory neuropathy was 53.1% and 0%, respectively. There were no other severe adverse events and no treatment-related deaths. Conclusion Reintroducing oxaliplatin can be both safe and effective. This may be a salvage option for patients with metastatic colorectal cancer who achieved a response or stable disease with prior oxaliplatin-based therapy followed by disease progression ≥6 months previously during prior oxaliplatin-based therapy.

Retrospective study of RAS/PIK3CA/BRAF tumor mutations as predictors of response to first-line chemotherapy with bevacizumab in metastatic colorectal cancer patients

BackgroundAfter analysis of minor RAS mutations (KRAS exon 3, 4/NRAS) in the FIRE-3 and PRIME studies, an expanded range of RAS mutations were established as a negative predictive marker for the efficacy of anti-EGFR antibody treatment. BRAF and PIK3CA mutations may be candidate biomarkers for anti-EGFR targeted therapies. However, it remains unknown whether RAS/PIK3CA/BRAF tumor mutations can predict the efficacy of bevacizumab in metastatic colorectal cancer. We assessed whether selection according to RAS/PIK3CA/BRAF mutational status could be beneficial for patients treated with bevacizumab as first-line treatment for metastatic colorectal cancer.MethodsOf the 1001 consecutive colorectal cancer patients examined for RAS, PIK3CA, and BRAF tumor mutations using a multiplex kit (Luminex®), we studied 90 patients who received combination chemotherapy with bevacizumab as first-line treatment for metastatic colorectal cancer. The objective response rate (ORR) and progression-free survival (PFS) were evaluated according to mutational status.ResultsThe ORR was higher among patients with wild-type tumors (64.3%) compared to those with tumors that were only wild type with respect to KRAS exon 2 (54.8%), and the differences in ORR between patients with wild-type and mutant-type tumors were greater when considering only KRAS exon 2 mutations (6.8%) rather than RAS/PIK3CA/BRAF mutations (18.4%). There were no statistically significant differences in ORR or PFS between all wild-type tumors and tumors carrying any of the mutations. Multivariate analysis revealed that liver metastasis and RAS and BRAF mutations were independent negative factors for disease progression after first-line treatment with bevacizumab.ConclusionsPatient selection according to RAS/PIK3CA/BRAF mutations could help select patients who will achieve a better response to bevacizumab treatment. We found no clinical benefit of restricting combination therapy with bevacizumab for metastatic colorectal cancer patients with EGFR-wild type tumors.

A phase I/II study of biweekly capecitabine and irinotecan plus bevacizumab as second-line chemotherapy in patients with metastatic colorectal cancer.

Background Triweekly capecitabine plus irinotecan (XELIRI) is not completely regarded as a valid substitute for fluorouracil, leucovorin, and irinotecan (FOLFIRI) in metastatic colorectal cancer (mCRC) because of the potential for greater toxicity. We conducted a phase I/II study to assess the efficacy and safety of biweekly XELIRI plus bevacizumab (BV) as second-line chemotherapy for mCRC. Methods Patients with mCRC who had received prior chemotherapy including oxaliplatin and BV and had a UGT1A1 genotype of wild-type or heterozygous for UGT1A1*6 or *28 were eligible for this study. Treatment comprised capecitabine 1,000 mg/m2 twice daily from the evening of day 1 to the morning of day 8, intravenous irinotecan on day 1, and BV 5 mg/kg on day 1 every 2 weeks. The phase I study consisted of two steps (irinotecan 150 and 180 mg/m2), and dose-limiting toxicity was assessed during the first treatment cycle. The primary endpoint of the phase II study was progression-free survival (PFS). Results The recommended dose of irinotecan was determined to be 180 mg/m2 in the phase I study. Between November 2010 and August 2013, 44 patients were enrolled in phase II. The patients’ characteristics were as follows (N=44): median age, 60 years (range 32–80); male/female, 21/23; and UGT1A1 wild-type/heterozygous, 29/15. The median PFS was 6.8 months (95% confidence interval, 5.3–8.2 months), and the primary endpoint was met. Median overall survival was 18.3 months. The response rate was 22.7%. There was no significant difference in PFS or overall survival according to UGT1A1 status. Grade 3 or higher adverse events were mainly neutropenia in six patients and diarrhea in five patients. There were no other severe adverse events or treatment-related deaths. Conclusion In mCRC patients with wild-type or heterozygous UGT1A1*6 or *28 genotype, biweekly XELIRI + BV is effective and feasible as second-line chemotherapy. Biweekly XELIRI + BV is considered a valid substitute for FOLFIRI + BV in mCRC.

Early hypertension is associated with better clinical outcomes in gastric cancer patients treated with ramucirumab plus paclitaxel

Anti-vascular endothelial growth factor (VEGF) therapeutics such as bevacizumab, which are widely used in cancer treatment, commonly leads to hypertension. Moreover, bevacizumab-induced hypertension is associated with improved clinical outcomes in several cancers. We retrospectively analyzed 89 patients with histologically confirmed advanced gastric cancer who received the human monoclonal anti-VEGF receptor-2 antibody ramucirumab plus paclitaxel at our hospital between June 2015 and October 2016 to evaluate the impact of treatment-associated hypertension occurring within the first two treatment cycles (“early hypertension”) on outcome. The objective response rate was 40%, median progression-free survival was 5.4 months, and overall survival was 10.4 months, which is similar to previous reports. Early hypertension in patients who received more than two cycles of ramucirumab + paclitaxel was associated with longer progression-free and overall survival. Objective response rates were also higher in patients with early hypertension. These data indicate that early hypertension may be predictive of better outcomes in gastric cancer patients who receive ramucirumab + paclitaxel treatment.

Two Cases of Long-Term Survival of Advanced Colorectal Cancer with Synchronous Lung Metastases Treated with mFOLFOX6/XELOX + Bevacizumab

Background: Colorectal cancer (CRC) with lung metastases has an unfavorable prognosis. However, nowadays, even advanced CRC can have a favorable outcome in certain cases. A complete response (CR) is a rare event in advanced CRC with lung metastases. Herein, we report 2 rare cases of advanced CRC attaining a CR. Case Presentation: Case 1 was a 58-year-old man who underwent laparoscopic ileocecal resection for cecum cancer with multiple metastases to the lungs in 2011. We performed treatment with mFOLFOX6 and bevacizumab chemotherapy in August 2011. After 11 courses, computed tomography (CT) revealed a CR to chemotherapy in February 2012. He has remained disease-free for 5 years and 3 months. Case 2 was a 70-year-old woman who underwent laparoscopic ileocecal resection for cecum cancer in August 2010. Recurrence of multiple metastases to both lungs was detected in November 2010. We started treatment with XELOX and bevacizumab chemotherapy in January 2011. In January 2011, CT after 14 courses revealed disappearance of the lung lesions, thereby indicating a CR. She has remained disease-free for 5 years and 4 months. Conclusion: We encountered 2 patients with CRC with lung metastases who were treated with chemotherapy leading to a CR. Cases resulting in such a desirable outcome are extremely rare.

Phase II trial of biweekly cetuximab and irinotecan as third-line therapy for pretreated KRAS exon 2 wild-type colorectal cancer

Efficacy and safety of biweekly cetuximab plus irinotecan were evaluated to provide guidance for its use in Japan as third‐line treatment for pretreated metastatic colorectal cancer (mCRC) patients harboring wild‐type KRAS exon 2. Objective response rate (ORR) was used as primary endpoint based on an expected proportion of 0.23 with confidence width of 0.298 (95% CI, 0.105‐0.403), which showed 35 to be the minimal participant number. Forty patients, refractory to first‐ and second‐line chemotherapy containing irinotecan, oxaliplatin, and fluoropyrimidine, were enrolled. ORR and disease control rate were 25.0% (95% CI: 11.5‐38.4) and 72.5% (95% CI: 56.8‐86.4), respectively. Median progression‐free survival (PFS), overall survival (OS), and number of courses were 5.70 months (95% CI: 2.7‐7.9), 15.1 months (95% CI: 11.8‐19.0), and 10.5 (range: 3.0‐31.0), respectively. Grade 3 adverse events were skin toxicity (12.5%), diarrhea (10.0%), neutropenia (5.0%), febrile neutropenia (5.0%), nausea (5.0%), anorexia (5.0%), and fatigue (2.5%). Cmax mean was 723.2 μg/mL after first dose. High area under the curve (AUC)last variance was associated with t1/2 range of 131.2‐1209.6 hours (median, 174.4 hours). Early tumor shrinkage (ETS) and median depth of response were 25.0% and 13.0%, respectively. Mutation frequencies in KRAS exon 3 or 4, NRAS, BRAF, and PIK3CA were 5.5%, 2.7%, 8.3%, and 5.5%, respectively. Multivariate Cox regression analysis assessed whether any gene mutations and ETS are predictors for PFS, and whether performance status, synchronous metastasis, and ETS are predictors for OS. Importantly, the data provide guidance for a biweekly cetuximab plus irinotecan regimen in mCRC patients.

Change in clinical outcomes during the transition of adjuvant chemotherapy for stage III colorectal cancer

Background There are robust data supporting the contribution of oxaliplatin (L-OHP) regarding clinical outcomes for colorectal cancer (CRC) in an adjuvant setting in European and US trials; however, there is no Japanese clinical evidence although L-OHP has been approved since 2009. We examined the transition of adjuvant chemotherapy for stage III colorectal cancer in our institute. Methods A total of 642 patients with histopathologically confirmed stage III CRC underwent curative surgery from 2005 to 2010. We examined disease free survival (DFS), overall survival (OS) and prognostic factors for stage III CRC patients who underwent adjuvant chemotherapy. Results A total of 509 patients received adjuvant chemotherapy. 3-year DFS and 5-year OS rates were 74.5% and 87.5%, respectively. The frequency of inclusion of L-OHP as adjuvant chemotherapy was increased after 2008. A total of 189 patients received adjuvant chemotherapy from 2005 to 2007 increasing to 320 patients from 2008 to 2010; the 5-year OS rates were 82.4% and 91.5%, respectively, and the 3-year DFS rates were 69.2% and 76.6%, respectively (OS, P = 0.007; DFS, P = 0.023). In univariate analysis, adjuvant chemotherapy including L-OHP was no significant deference compared to FU monotherapy. (OS: HR 0.88, 95%CI 0.4–1.91, p = 0.75, DFS: HR 0.78, 95%CI 0.21–2.3, p = 0.29). In multivariate analysis, the OS was predicted by means of N stage (HR = 2; 95%CI, 1.1–3.8; P = 0.02) and pathology (HR = 0.28; 95%CI, 0.13–0.59; P = 0.0008). The DFS was predicted by means of N stage (HR = 2.67; 95%CI, 1.82–3.9; P < 0.05), T stage (HR = 1.61; 95%CI, 1.1–2.3; P = 0.01) pathology (HR = 0.47; 95%CI, 0.29–0.75; P < 0.05) and venous invasion (HR = 2.06; 95%CI, 1.12–3.77; P = 0.01). Conclusions Clinical outcomes of stage III CRC patients receiving adjuvant chemotherapy improved. The frequency of L-OHP usage was increasing annually, however it was no influence for clinical outcomes in this study. It will be necessary to reevaluate additional effect of L-OHP with more patients.

Anticoagulant therapy for venous thromboembolism detected by Doppler ultrasound in patients with metastatic colorectal cancer receiving bevacizumab

Background Doppler ultrasound imaging is useful for management of venous thromboembolism associated with a subclavicular implantable central venous access system in patients receiving bevacizumab (Bev). We investigated the efficacy and safety of our anticoagulant regimen based on Doppler findings. Methods Patients aged ≤75 years with metastatic colorectal cancer, no history of thromboembolism, and no prior use of Bev received chemotherapy plus Bev. Doppler ultrasound imaging of the deep venous system to detect thrombosis was performed after the first course of Bev and repeated after the third course in patients with asymptomatic thrombosis. Indications for anticoagulant therapy in patients with asymptomatic thrombosis were as follows: enlarging thrombus (E), thrombus >40 mm in diameter (S), thrombus involving the superior vena cava (C), and decreased blood flow (V). Results Among 79 patients enrolled in this study, asymptomatic thrombosis was detected in 56 patients (70.9%) by Doppler ultrasound imaging after the first course of Bev and there was no thrombus in 23 patients (29.1%). Of these 56 patients, 11 (19.6%) received anticoagulant therapy with warfarin, including eight after the first course and three after follow-up imaging. S + V was observed in four of 11 patients (36.4%), as well as V in two (18.2%), S + V + C in one (9.1%), E + S + V in one (9.1%), E + C in one (9.1%), E in one (9.1%), and C in one (9.1%). All patients resumed chemotherapy, including seven who resumed Bev. Improvement or stabilization of thrombi was achieved in ten patients (90.9%). Only one patient had symptomatic thromboembolism. Mild bleeding due to anticoagulant therapy occurred in six patients (54.5%), but there were no treatment-related severe adverse events or deaths. Severe thromboembolism was not observed in the other 68 patients. Conclusion Our anticoagulant protocol for asymptomatic thrombosis detected by Doppler ultrasound imaging was effective at preventing severe thromboembolism during continued treatment with Bev.

Association between intratumoral HER2 heterogeneity (IHH) and trastuzumab (T-mab) efficacy in HER2 positive–gastric cancer (GC).

92 Background: ToGA study showed superiority of adding T-mab to standard chemotherapy and a positive correlation between HER2 expression levels and the T-mab efficacy. In gastric cancer IHH is frequently recognized but its clinical impact on T-mab efficacy is unclear. Methods: Patients who were treated with T-mab and had surgical specimens available for IHC test were retrospectively examined. When all tumor cells overexpressed HER2 protein by IHC, the tumor was defined as non-HER2-heterogeneous. The others were defined as HER2-heterogeneous. Progression-free survival (PFS) and overall survival (OS) were estimated using by Kaplan-Meier methods and compared by the log-rank test. The level of significance was set to p<0.05 and all statistical tests were two-sided. Results: 23 patients were enrolled. Their median age was 68 years and 83% were male. PS 0, GEJ cancer, intestinal type histology, visceral metastasis (lung or liver), and previous chemotherapy were found in 57%, 35%, 83%, 57%, and 57% of them, resp...