Proportions and characteristics of interval cancer in annual fecal immunochemical test screening and postcolonoscopy colorectal cancer: Results from a Japanese multicenter prospective study using questionnaires, the C-DETECT study

OBJECTIVES

There are several types of colorectal cancer (CRC) according to the detection methods and intervals, including interval CRC (iCRC) and postcolonoscopy CRC (PCCRC). We aimed to examine their proportions and characteristics.

METHODS

We conducted a multicenter prospective study using questionnaires in Japan ("C-DETECT study"), in which differences in CRC characteristics according to detection methods and intervals were examined from consecutive adult patients. Because the annual fecal immunochemical test (FIT) was used in population-based screening, the annual FIT-iCRC was assessed.

RESULTS

In total, 1241 CRC patients (1064 with invasive CRC) were included. Annual FIT-iCRC (a), 3-year PCCRC (b), and CRC detected within 1 year after a positive FIT with noncompliance to colonoscopy (c) accounted for 4.5%, 7.0%, and 3.9% of all CRCs, respectively, and for 3.9%, 5.4%, and 4.3% of invasive CRCs, respectively. The comparison among these (a, b, c) and other CRCs (d) demonstrated differences in the proportions of ≥T2 invasion ([a] 58.9%, [b] 44.8%, [c] 87.5%, [d] 73.0%), metastasis ([a] 33.9%, [b] 21.8%, [c] 54.2%, [d] 43.9%), right-sided CRC ([a] 42.9%, [b] 40.2%, [c] 18.8%, [d] 28.6%), and female sex ([a] 53.6%, [b] 49.4%, [c] 27.1%, [d] 41.6%). In metastatic CRC, (a) and (b) showed a higher proportions of BRAF mutations ([a] [b] 12.0%, [c] [d] 3.1%).

CONCLUSIONS

Annual FIT-iCRC and 3-year PCCRC existed in nonnegligible proportions. They were characterized by higher proportions of right-sided tumors, female sex, and BRAF mutations. These findings suggest that annual FIT-iCRC and 3-year PCCRC may have biological features different from those of other CRCs.

Baseline ctDNA gene alterations as a biomarker of survival after panitumumab and chemotherapy in metastatic colorectal cancer

Certain genetic alterations and right-sided primary tumor location are associated with resistance to anti-epidermal growth factor (EGFR) treatment in metastatic colorectal cancer (mCRC). The phase 3 PARADIGM trial (n = 802) demonstrated longer overall survival with first-line anti-EGFR (panitumumab) versus antivascular endothelial growth factor (bevacizumab) plus modified FOLFOX6 in patients with RAS wild-type mCRC with left-sided primary tumors. This prespecified exploratory biomarker analysis of PARADIGM (n = 733) evaluated the association between circulating tumor DNA (ctDNA) gene alterations and efficacy outcomes, focusing on a broad panel of gene alterations associated with resistance to EGFR inhibition, including KRAS, NRAS, PTEN and extracellular domain EGFR mutations, HER2 and MET amplifications, and ALK, RET and NTRK1 fusions. Overall survival was prolonged with panitumumab plus modified FOLFOX6 versus bevacizumab plus modified FOLFOX6 in patients with ctDNA that lacked gene alterations in the panel (that is, negative hyperselected; median in the overall population: 40.7 versus 34.4 months; hazard ratio, 0.76; 95% confidence interval, 0.62-0.92) but was similar or inferior with panitumumab in patients with ctDNA that contained any gene alteration in the panel (19.2 versus 22.2 months; hazard ratio, 1.13; 95% confidence interval, 0.83-1.53), regardless of tumor sidedness. Negative hyperselection using ctDNA may guide optimal treatment selection in patients with mCRC. ClinicalTrials.gov registrations: NCT02394834 and NCT02394795 .

Bevacizumab, Irinotecan, and Biweekly Trifluridine/Tipiracil for Metastatic Colorectal Cancer: MODURATE, a Phase Ib Study

BACKGROUND

In this phase Ib study MODURATE, we optimized the dosing schedule and tested the efficacy and safety of trifluridine/tipiracil, irinotecan, and bevacizumab in patients with metastatic colorectal cancer with fluoropyrimidine and oxaliplatin treatment failure.

METHODS

We included a dose escalation (3 + 3 design) and an expansion cohort. Patients were administered trifluridine/tipiracil (25-35 mg/m2 twice daily, days 1-5), irinotecan (150-180 mg/m2, day 1), and bevacizumab (5 mg/kg, day 1) every 2 weeks. The recommended phase II dose (RP2D) in the dose escalation cohort was administered to at least 15 patients in both cohorts combined.

RESULTS

Twenty-eight patients were enrolled. Five dose-limiting toxicities were observed. RP2D was defined as trifluridine/tipiracil 35 mg/m2, irinotecan 150 mg/m2, and bevacizumab 5 mg/kg. Of 16 patients who received RP2D, 86% (14/16) experienced grade ≥3 neutropenia without febrile neutropenia. Dose reduction, delay, and discontinuation occurred in 94%, 94%, and 6% of patients, respectively. Three patients (19%) showed partial response and 5 had stable disease for >4 months, with a median progression-free and overall survival of 7.1 and 21.7 months, respectively.

CONCLUSION

Biweekly trifluridine/tipiracil, irinotecan, and bevacizumab administration may have moderate antitumor activity with high risk of severe myelotoxicity in previously treated patients with metastatic colorectal cancer [UMIN Clinical Trials Registry (UMIN000019828) and Japan Registry of Clinical Trials (jRCTs041180028)].

Ramucirumab plus FOLFIRI as second-line treatment for patients with RAS wild-type metastatic colorectal cancer previously treated with anti-EGFR antibody: JACCRO CC-16

BACKGROUND

Chemotherapy in combination with anti-epidermal growth factor receptor (EGFR) antibody is considered a first-line treatment regimen for RAS wild-type and left-sided metastatic colorectal cancer (mCRC), whereas second-line treatment regimens have not yet been established. Few studies have prospectively evaluated second-line treatment with anti-vascular endothelial growth factor antibody after first-line anti-EGFR antibody therapy for RAS wild-type mCRC.

PATIENTS AND METHODS

This non-randomized phase II trial investigated the clinical outcomes of second-line ramucirumab (RAM) plus fluorouracil, levofolinate, and irinotecan (FOLFIRI) after first-line anti-EGFR antibody in combination with doublet or triplet regimen in patients with RAS wild-type mCRC. The primary endpoint was the 6-month progression-free survival (PFS) rate. The secondary endpoints were PFS, overall survival (OS), objective response rate (ORR), rate of early tumor shrinkage (ETS), and safety. We hypothesized a threshold 6-month PFS rate of 30% and an expected 6-month PFS rate of 45%. Treatment was considered effective if the lower limit of the 90% confidence interval (CI) of the 6-month PFS rate was >0.30.

RESULTS

Ninety-two patients were enrolled in the study. The primary tumor was located on the left side in 86 (95.6%) patients. Twenty (22.0%) patients had received triplet plus cetuximab as previous therapy. Six-month PFS rate was 58.2% (90% CI 49.3% to 66.2%) with a median PFS of 7.0 months (95% CI 5.7-7.6 months). Median OS was 23.6 months (95% CI 16.5-26.3 months). The ORR and ETS rate were 10.7% and 16.9%, respectively, in 83 patients with measurable lesions. The 6-month PFS rate was comparable between patients previously treated with doublet and triplet regimens; however, median PFS was longer for the doublet regimen (7.4 versus 6.4 months, P = 0.036).

CONCLUSIONS

Our study demonstrated prospectively that RAM plus FOLFIRI is an effective second-line treatment after anti-EGFR antibody-containing first-line therapy in RAS wild-type and left-sided mCRC. Furthermore, the results were similar for patients who were previously treated with triplet regimen.

Panitumumab vs Bevacizumab Added to Standard First-line Chemotherapy and Overall Survival Among Patients With RAS Wild-type, Left-Sided Metastatic Colorectal Cancer: A Randomized Clinical Trial

Importance

For patients with RAS wild-type metastatic colorectal cancer, adding anti-epidermal growth factor receptor (anti-EGFR) or anti-vascular endothelial growth factor (anti-VEGF) monoclonal antibodies to first-line doublet chemotherapy is routine, but the optimal targeted therapy has not been defined.

Objective

To evaluate the effect of adding panitumumab (an anti-EGFR monoclonal antibody) vs bevacizumab (an anti-VEGF monoclonal antibody) to standard first-line chemotherapy for treatment of RAS wild-type, left-sided, metastatic colorectal cancer.

Design, Setting, and Participants

Randomized, open-label, phase 3 clinical trial at 197 sites in Japan in May 2015-January 2022 among 823 patients with chemotherapy-naive RAS wild-type, unresectable metastatic colorectal cancer (final follow-up, January 14, 2022).

Interventions

Panitumumab (n = 411) or bevacizumab (n = 412) plus modified fluorouracil, l-leucovorin, and oxaliplatin (mFOLFOX6) every 14 days.

Main Outcomes and Measures

The primary end point, overall survival, was tested first in participants with left-sided tumors, then in the overall population. Secondary end points were progression-free survival, response rate, duration of response, and curative (defined as R0 status) resection rate.

Results

In the as-treated population (n = 802; median age, 66 years; 282 [35.2%] women), 604 (75.3%) had left-sided tumors. Median follow-up was 61 months. Median overall survival was 37.9 months with panitumumab vs 34.3 months with bevacizumab in participants with left-sided tumors (hazard ratio [HR] for death, 0.82; 95.798% CI, 0.68-0.99; P = .03) and 36.2 vs 31.3 months, respectively, in the overall population (HR, 0.84; 95% CI, 0.72-0.98; P = .03). Median progression-free survival for panitumumab vs bevacizumab was 13.1 vs 11.9 months, respectively, for those with left-sided tumors (HR, 1.00; 95% CI, 0.83-1.20) and 12.2 vs 11.4 months overall (HR, 1.05; 95% CI, 0.90-1.24). Response rates with panitumumab vs bevacizumab were 80.2% vs 68.6%, respectively, for left-sided tumors (difference, 11.2%; 95% CI, 4.4%-17.9%) and 74.9% vs 67.3% overall (difference, 7.7%; 95% CI, 1.5%-13.8%). Median duration of response with panitumumab vs bevacizumab was 13.1 vs 11.2 months for left-sided tumors (HR, 0.86; 95% CI, 0.70-1.10) and 11.9 vs 10.7 months overall (HR, 0.89; 95% CI, 0.74-1.06). Curative resection rates with panitumumab vs bevacizumab were 18.3% vs 11.6% for left-sided tumors; (difference, 6.6%; 95% CI, 1.0%-12.3%) and 16.5% vs 10.9% overall (difference, 5.6%; 95% CI, 1.0%-10.3%). Common treatment-emergent adverse events were acneiform rash (panitumumab: 74.8%; bevacizumab: 3.2%), peripheral sensory neuropathy (panitumumab: 70.8%; bevacizumab: 73.7%), and stomatitis (panitumumab: 61.6%; bevacizumab: 40.5%).

Conclusions and Relevance

Among patients with RAS wild-type metastatic colorectal cancer, adding panitumumab, compared with bevacizumab, to standard first-line chemotherapy significantly improved overall survival in those with left-sided tumors and in the overall population.

Trial Registration

ClinicalTrials.gov Identifier: NCT02394795.

Genetic medicine in companion diagnostics of germline BRCA testing of Japanese pancreatic cancer patients

In 2021, Japan's national health insurance made germline BRCA (g.BRCA) testing available to unresectable pancreatic cancer (PC) patients as a companion diagnostic (CD) of the PARP inhibitor. This study investigated the incidence of the g.BRCA variant (g.BRCAv.) and the status of the genetic medicine associated with its testing. A total of 110 PC patients underwent the testing, five of whom (4.5%) had a deleterious g.BRCA2v. (all truncations) but no g.BRCA1v. The turnaround time (TAT) to the doctors was 13 days, and to the patients, 17 days. A higher incidence of a BRCA-related family history and a shorter TAT were seen in the g.BRCAv. patients, but they were insignificant (p = 0.085 and p = 0.059, respectively). Genetic counseling was not performed for three g.BRCA2v. patients because two of them had no accessible relatives and one died of the cancer before the genetic report was completed. Two families underwent generic counseling and testing based on the patient's genetic data. g.BRCAv. is recognized in a small fraction of PC cases, and the following genetic counseling is done more for the relatives than for the patients. TAT was constant and did not affect much on the genetic counseling, but the earlier testing is expected for patients with a deadly cancer.

Negative hyperselection of patients with RAS wild-type metastatic colorectal cancer for panitumumab: A biomarker study of the phase III PARADIGM trial

11

Background: The PARADIGM trial showed longer median overall survival (OS) with first-line mFOLFOX6 plus panitumumab (PAN) vs bevacizumab (BEV) in patients (pts) with RAS wild type (WT) and left-sided metastatic colorectal cancer (mCRC) (37.9 vs 34.3 months, respectively; hazard ratio [HR], 0.82; P=0.031) and similar OS in right-sided pts (HR 1.09; Yoshino T, et al. ASCO 2022 LBA1). We evaluated the usefulness of negative hyperselection by gene alterations in ctDNA related to primary resistance to anti-EGFR therapy. Methods: Baseline plasma ctDNA (>10 ng/mL and >10 nM DNA) from pts enrolled in the biomarker study (NCT02394834) was assessed using a custom panel (PlasmaSELECT-R 91, PGDx). Preplanned gene alterations for hyperselection included KRAS, NRAS, PTEN, and extracellular domain EGFR mutations, HER2 and MET amplifications, and ALK, RET, or NTRK1 fusions. Results: Among 802 pts in the full analysis set, 733 (91%) had evaluable pretreatment samples for ctDNA analysis. Of these pts, 204 (28%) had at least 1 gene alteration, including KRAS/NRAS (8%), BRAF V600E (11%), PTEN (5%), EGFR (3%), HER2 (5%), MET (1%), and fusions (1%). In 529 (72%) hyperselected pts without any gene alterations, OS tended to be longer with PAN vs BEV regardless of primary sidedness; the OS HRs ranged from 0.76 to 0.82, and the median OS gains ranged from 6.6 to 8.0 months (Table). Meanwhile, OS was similar or inferior with PAN vs BEV irrespective of the primary sidedness in pts with any of these gene alterations (Table). Conclusions: Negative hyperselection using ctDNA rather than tumor sidedness may identify appropriate pts for first-line PAN over BEV. These results warrant further validation in additional cohorts. Clinical trial information: NCT02394834 . [Table: see text]

Biomarker analysis for patients with pancreatic cancer treated with nanoliposomal irinotecan plus 5-fluorouracil/leucovorin

BACKGROUND

Nanoliposomal irinotecan plus fluorouracil/leucovorin (5-FU/LV) is a standard second-line therapy for patients with pancreatic cancer. Identification of biomarkers is important to determine appropriate treatment strategies. We investigated the clinical practice outcomes and biomarkers associated with the nanoliposomal irinotecan plus 5-FU/LV regimen.

METHODS

We retrospectively reviewed the data of patients treated with nanoliposomal irinotecan plus 5-FU/LV as a second or subsequent treatment after gemcitabine-based therapy between June 2020 and March 2021 at Shizuoka Cancer Center.

RESULTS

We analyzed 55 consecutive patients who met the selection criteria. At a median of 9.4 months, median progression-free survival (PFS) and median overall survival (OS) were 2.3 and 6.6 months, respectively. Multivariate analysis showed that Glasgow prognostic score (GPS) was significantly associated with PFS (hazard ratio [HR] 2.16; 95% confidence interval [CI] 1.09-4.30; P = 0.028) and OS (0 vs. 1 or 2: HR 2.46; 95% CI 1.15-5.25; P = 0.029). The OS was significantly longer in patients with CA19-9 response than in those without CA19-9 response (12.6 vs. 5.6 months; HR 0.24; 95% CI 0.08-0.75; P = 0.014).

CONCLUSIONS

Nanoliposomal irinotecan was efficacious and tolerable in clinical practice. GPS and CA19-9 response were good candidates as predictive biomarkers, whereas GPS was a good candidate prognostic biomarker for the nanoliposomal irinotecan plus 5-FU/LV regimen.

Discordance of microsatellite instability and mismatch repair immunochemistry occurs depending on the cancer type

Microsatellite instability (MSI) and deficiency of mismatch repair (dMMR) are key markers for predicting the response of immune checkpoint inhibitors (ICIs) and screening for Lynch syndrome (LS). This study examined the incidences of and factors associated with the concordance of MSI and MMR in human cancers. A total of 518 formalin-fixed cancer tissues were analyzed for MSI and MMR immunohistochemistry (IHC). MSI was analyzed by a PCR-based method using Promega markers. Concordance with MMR expression and factors associated with concordance were analyzed. In 2 colorectal cancer samples, MMR IHC failed due to inadequate staining conditions. In the remaining 516 cancers, a high level of MSI (MSI-H) was identified in 113 cases, and dMMR was identified in 112. The concordance of MSI and MMR IHC was 98.3%. Only 9 cases (4 pancreatobiliary, 3 colorectal, and 2 endometrial cancers) were discordant. Of the 113 MSI-H cases, 4 (3.5%) were proficient MMR (pMMR); of the 403 microsatellite stability (MSS) cases, 5 (1.2%) were dMMR. The independent factors associated with MSI-H/dMMR included meeting Amsterdam II criteria, assay purpose, and sampling method. Multivariate analysis revealed that cancer type (gastrointestinal cancers or others) was associated with concordance of MSI and MMR IHC. Three LS cases with pancreatic or endometrial cancer demonstrated MSS and dMMR, and one biliary cancer showed MSI-H and pMMR. Discordance between MSI and MMR IHC occasionally occurs in pancreaticobiliary and endometrial cancers. When suspected, both MSI and MMR IHC should be done to judge the ICI indication and screen for LS.

Effectiveness and safety of gemcitabine plus nab-paclitaxel in elderly patients with advanced pancreatic cancer: a single-center retrospective cohort study

PURPOSE

This study aimed to evaluate the effectiveness and safety of gemcitabine (GEM) plus nab-paclitaxel (GnP) in patients aged ≥ 75 years with advanced pancreatic cancer and compare it with monotherapy (GEM or S-1).

METHODS

We retrospectively reviewed the data of consecutive patients with advanced pancreatic cancer aged ≥ 75 years who received either GnP or monotherapy (GEM or S-1) between January 2014 and May 2020. The primary efficacy outcome was overall survival (OS).

RESULTS

A total of 96 patients were included in this study; 51 were treated with GnP and 45 with monotherapy (31 with GEM and 14 with S-1). The median OS and progression-free survival were 10.8 and 6.7 months in the GnP group and 10.7 and 4.3 months in the monotherapy group, respectively. The treatment effect on OS was consistently favorable in the GnP group across most subgroups, particularly in patients with locally advanced cancer, modified Glasgow prognostic score of 0 or 1, and neutrophil/lymphocyte ratio < 3.1. The disease control rates were 76% and 48% in the GnP and monotherapy groups, respectively, and grade 3 or 4 neutropenia occurred in 23 (45%) and 11 (24%) patients of the GnP and monotherapy groups, respectively.

CONCLUSIONS

This study demonstrated that GnP was not superior to monotherapy with regard to OS. However, multivariate analysis showed that GnP treatment positively affected the OS and could be considered as a treatment option, even for elderly patients.

Panitumumab (PAN) plus mFOLFOX6 versus bevacizumab (BEV) plus mFOLFOX6 as first-line treatment in patients with RAS wild-type (WT) metastatic colorectal cancer (mCRC): Results from the phase 3 PARADIGM trial

LBA1

Background: PARADIGM is the first prospective trial to test the superiority of PAN vs. BEV in combination with standard doublet first-line chemotherapy for patients (pts) with RAS WT mCRC and left-sided primary tumors. Methods: This open-label, multicenter trial in Japan (NCT02394795) randomly selected pts with chemotherapy-naive RAS WT mCRC to PAN + mFOLFOX6 or BEV + mFOLFOX6. Overall survival (OS) as primary endpoint was hierarchically tested in patients with left-sided tumors, followed by those in the full-analysis set (FAS) population. Key secondary endpoints included progression-free survival (PFS), response rate (RR), and curative resection (R0) rate. Results: From May 2015 to June 2017, 823 pts were randomized; 12 did not receive protocol treatment and 9 were excluded due to major deviation of inclusion criteria. A total of 400 pts received PAN and 402 pts received BEV as FAS; 312 and 292 pts had left-sided primary tumors, respectively. OS was analyzed after 448 OS events in left-sided pts with a median follow-up of 61 months. PAN significantly improved OS vs. BEV in both populations: left-sided (HR, 0.82; 95.798% CI, 0.68-0.99, p = .031, which crossed the boundary of significance [0.042]), and FAS (HR, 0.84; 95% CI, 0.72-0.98; p = .030, with < 0.05 as the boundary). Although PFS was comparable between treatment groups, RR and R0 resection rates were higher with PAN compared with BEV (Table). HR for OS in the right-sided population was 1.09. No new safety signal was observed. Conclusions: PAN significantly improved OS vs. BEV in combination with mFOLFOX6 in pts with RAS WT and left-sided mCRC, establishing a standard first-line combination regimen for this population. Clinical trial information: NCT02394795. [Table: see text]

Present status of germline findings in precision medicine for Japanese cancer patients: issues in the current system

OBJECTIVE

Since 2019, precision cancer medicine has been covered by national insurance in Japan; however, to date, germline findings have not been fully reported. The aim of this study was to evaluate the current status and raise a problem of germline finding analysis and disclosure in Japanese precision cancer medicine.

METHODS

Germline findings of 52 genes were examined in 296 cases with advanced cancer by a case series study.

RESULTS

Six (2.0%) cases were examined by the Oncoguide™ NCC Oncopanel with germline testing, but no germline findings were reported. The remaining 290 (98.0%) cases were analyzed by FoundationOne® CDx (tumor-only testing), which recognized 404 pathogenic variants; those of BRCA1/2 were recognized in 16 (5.5%) tumors. Our institutional algorithm suggested 39 candidate germline findings in 34 cases, while the public algorithm listed at least 91 candidate germline findings. Four germline findings had been previously identified (BRCA1: 3 and ATM: 1). Nine of 30 cases with candidate germline findings excluding these known germline findings refused or deferred germline testing. Only 4 of 16 cases that received counseling underwent germline testing, and those 4 revealed 3 germline findings (BRCA2, CDK4 and RAD51C); in total, 8 (2.7%) germline findings were revealed. Reasons for refusing genetic counseling and/or germline testing included extra hospital visits, added expense for germline testing due to limited national insurance coverage, poor patient physical condition and no known family members associated with the possible germline finding.

CONCLUSIONS

In current Japanese precision cancer medicine, only a small fraction of the patients undergoes germline testing and demonstrated germline finding. The current results suggested a need for earlier indications for precision cancer medicine, broader insurance coverage and more efficient germline finding prediction algorithms, to increase the number of germline testings and to improve the following managements.

A randomized phase II trial of preoperative chemotherapy of S-1/CDDP with or without trastuzumab followed by surgery in HER2 positive advanced gastric or esophagogastric junction adenocarcinoma with extensive lymph node metastasis: Japan Clinical Oncology Group study JCOG1301C (Trigger Study)

285

Background: The efficacy of trastuzumab has been established for HER2-positive advanced gastric cancer patients with metastatic disease. However, it remains unclear if the addition of trastuzumab to preoperative chemotherapy is effective for treatment of HER2-positive locally advanced gastric cancer. Methods: Eligible patients with HER2-positive gastric cancer with extensive lymph node metastasis were randomized to preoperative S-1/cisplatin (SP) (group A) or SP plus trastuzumab (group B). In both groups, patients received S-1, 80–120 mg/body, on days 1–14 and cisplatin, 60 mg/m2, on day 1, q21, 3-4 courses. Additionally, in group B, patients received infusions of trastuzumab (first course 8 mg/kg followed by 6 mg/kg, day 1). After gastrectomy, adjuvant chemotherapy with S-1 was performed for 1 year in both groups. The primary endpoint was overall survival, and the sample size was planned to be 130 patients in total, expecting a 10% increase in the 3-year overall survival (70% vs 80%) with a 1-sided alpha of 0.2, a power of 0.75. Results: The study was terminated in March 2021 due to slow patient accrual. In total, 46 patients were randomized to either group A (22 patients) or group B (24 patients). Patient characteristics were well balanced between the groups. Planned preoperative chemotherapy was completed in 20 patients (90.9%) in group A and in 23 patients (95.8%) in group B, and R0 resection was achieved in 20 patients (90.9%) in group A and 22 patients (91.7%) in group B. The incidences of grade 3 or 4 hematological/non-hematological adverse events during preoperative chemotherapy were 27.3/18.2% in group A and 4.2/8.3% in group B. Objective response rate (CR/PR) tended to be higher in group B (66.7% [16/24]) than in group A (36.4% [8/22], p = 0.08). Pathological response rate (> grade 1b in Japanese classification, 22.7% [5/22] vs. 50.0% [12/24], p = 0.07) and the proportion of patients achieving downstage to ypStage 0/I/II (22.7% [5/22] vs. 50.0% [12/24], p = 0.07) were also higher in group B than in group A. Conclusions: Preoperative chemotherapy with SP plus trastuzumab was feasible, and tended to show better radiological and pathological response rates. Better survival outcomes are expected by adding trastuzumab to preoperative chemotherapy with SP for locally advanced gastric cancer with extensive nodal metastasis. Clinical trial information: UMIN000016920.

Usefulness of an S-1 dosage formula: An exploratory analysis of randomized clinical trial (JCOG1001)

288

Background: Although the S-1 dose is determined by body surface area (BSA), its blood concentration and adverse events are affected by renal function. One study had reported the clinical utility of an S-1 dosage formula for calculating the dose for target blood concentration based on renal function (Booka E. Gastric Cancer 2016;19:876-86.). The present study aimed to explore the usefulness of this formula in adjuvant chemotherapy for gastric cancer. Methods: Ad hoc analyses was performed using data from patients enrolled in a phase III trial, JCOG1001, to evaluate the role of bursectomy for resectable advanced gastric cancer. In the abovementioned trial, patients with stage II/III received adjuvant S-1 chemotherapy based on BSA. The present study calculated the S-1 dose using the following formula: 1447.8 * (14.5+0.301*CLcr+8.23*SEX [male=1, female=0])*BSA (mg/day). Patients were divided into three groups, overdosed (OD), equal dosed (ED), and underdosed (UD), by comparing the initial dosage administered with that recommended by the formula. Results: Among the 686 eligible pts, 324, 304, and 58 were respectively classified as OD/ED/UD, with the following characteristics: median age, 67.5/64/53.5 years; men 188/229/57 (58%/75%/98%); undifferentiated type, 168/172/38 (52%/57%/66%); and pStage III, 212/200/41 (65%/66%/71%). Median relative dose intensity in OD/ED/UD pts was 93.8%/108.8%/75.0% based on the formula-recommended dose. The planned adjuvant S-1 therapy was completed in 69%/74%/74%, dose reduction and treatment schedule alteration were required in 31%/21%/9% and 20%/17%/9%, and treatment was terminated due to adverse events in 25%/18%/12%. The 5-year relapse-free (RFS) and overall survival (OS) OD/ED/UD patients were 66.6%/69.2%/74.0% and 77.0%/74.3%/77.3%, in pStage II 80.2%/85.6%/93.8% and 88.3%/90.1%/100%, and pStage III 59.6%/60.4%/65.8% and 67.0%/70.0%/67.7%, respectively. OD pts had significantly higher incidences of grade 3 or higher anemia, thrombocytopenia, diarrhea, stomatitis than ED and UD pts. Conclusions: Despite no difference in survival, this formula improved treatment compliance in OD patients receiving adjuvant S-1 chemotherapy for gastric cancer.[Table: see text]

Microsatellite instability is biased in Amsterdam II-defined Lynch-related cancer cases with family history but is rare in other cancers: a summary of 1000 analyses

Background

Microsatellite instability (MSI) is a key marker for predicting the response of immune checkpoint inhibitors (ICIs) and for screening Lynch syndrome (LS).

Aim

This study aimed to see the characteristics of cancers with high level of MSI (MSI-H) in genetic medicine and precision medicine.

Methods

This study analyzed the incidence of MSI-H in 1000 cancers and compared according to several clinical and demographic factors.

Results

The incidence of MSI-H was highest in endometrial cancers (26.7%, 20/75), followed by small intestine (20%, 3/15) and colorectal cancers (CRCs)(13.7%, 64/466); the sum of these three cancers (15.6%) was significantly higher than that of other types (2.5%)(P < 0.0001). MSI-H was associated with LS-related cancers (P < 0.0001), younger age (P = 0.009), and family history, but not with smoking, drinking, or serum hepatitis virus markers. In CRC cases, MSI-H was significantly associated with a family history of LS-related cancer (P < 0.0001), Amsterdam II criteria [odds ratio (OR): 5.96], right side CRCs (OR: 4.89), and multiplicity (OR: 3.31). However, MSI-H was very rare in pancreatic (0.6%, 1/162) and biliary cancers (1.6%, 1/64) and was null in 25 familial pancreatic cancers. MSI-H was more recognized in cancers analyzed for genetic counseling (33.3%) than in those for ICI companion diagnostics (3.1%)(P < 0.0001). Even in CRCs, MSI-H was limited to 3.3% when analyzed for drug use.

Conclusions

MSI-H was predominantly recognized in LS-related cancer cases with specific family histories and younger age. MSI-H was limited to a small proportion in precision medicine especially for non-LS-related cancer cases.

Efficacy and safety of S-1 following gemcitabine with cisplatin for advanced biliary tract cancer

Background Combination therapy of gemcitabine with cisplatin (GC) is a standard first-line therapy for unresectable or recurrent biliary tract cancer (BTC). S-1 is often used as a second-line therapy in clinical practice, based on the results of some clinical studies investigating its efficacy and safety following gemcitabine monotherapy. However, few studies have reported on the clinical outcomes of S-1 following GC. The purpose of this study was to elucidate the efficacy and safety of S-1 following GC for unresectable and recurrent BTC. Methods We retrospectively collected the data of 116 patients (pts) who were treated with S-1 as a second-line therapy following GC for unresectable or recurrent BTC at Shizuoka Cancer Center (November 2009 to July 2019). Results Of these 116 pts., 84 were assessable. Patient characteristics were as follows: intrahepatic bile duct/extrahepatic bile duct/gallbladder cancer, 30/23/31 pts.; metastatic/recurrent/locally advanced, 57/17/10 pts. The median time to treatment failure and overall survival were 2.5 and 6.0 months, respectively. Among 65 pts. with measurable lesions, the overall response rate was 3.1% (2/65 pts) and the disease control rate was 24.6% (19/65 pts). The common grade 3/4 toxicities included anemia (12%), neutropenia (4%), infections (16%), fatigue (6%), and diarrhea (4%). Dose reduction or treatment schedule modification of S-1 was required in 29 pts. (34.5%), and 17 pts. (20%) terminated S-1 due to adverse events. Conclusions The efficacy and safety of S-1 following GC were almost the same as those of S-1 following GEM monotherapy for unresectable or recurrent BTC.

Impact of tumor growth rate during preceding treatment on tumor response to nivolumab or irinotecan in advanced gastric cancer

Background

Nivolumab (NIVO) and irinotecan (IRI) are standard treatments for refractory advanced gastric cancer (AGC); however, it is unclear which drug should be administered first or in which cases. The tumor growth rate (TGR) during preceding treatment is reported to be associated with tumor response in metastatic colorectal cancer patients treated with regorafenib or trifluridine/tipiracil, suggesting that TGR may be useful for drug selection. Therefore, we evaluated the association between TGR during preceding treatment and the tumor response to NIVO or IRI.

Patients and methods

We retrospectively evaluated consecutive AGC patients treated with NIVO or IRI and divided them into slow-growing (Slow) and rapid-growing (Rapid) groups according to TGR and the presence or absence of new lesions (NL+/NL−, respectively) during preceding treatment (Slow group: NL− with low TGR <0.30%/day; Rapid group: NL+ or high TGR ≥0.30%/day).

Results

A total of 117 patients (Rapid/Slow groups, 72/45; NIVO/IRI groups, 32/85) were eligible. All baseline characteristics except peritoneal metastases were similar between patients treated with NIVO and IRI in the Rapid and Slow groups. The response rate was significantly higher in patients treated with NIVO compared with IRI [31%/3%; odds ratio (OR), 13.8; P = 0.01; adjusted OR, 52; P = 0.002] in the Slow group, but there was no difference between patients treated with NIVO and IRI (5%/8%; OR, 0.68; P = 0.73; adjusted OR, 0.94; P = 0.96) in the Rapid group. Disease control rate, progression-free survival, and overall survival were consistent with these results.

Conclusions

Our findings suggest that NIVO treatment is a more favorable option for patients with slow-growing tumors, and NIVO and IRI are similarly recommended for patients with rapid-growing tumors in refractory AGC. TGR and NL emergence during preceding treatment may be helpful for drug selection and warrant further investigation.

•

NIVO and IRI are standard treatments for refractory AGC, although it is unclear which should be administered first.

•

TGR may be useful for drug selection, therefore we evaluated the association between TGR and the tumor response to NIVO or IRI.

•

In the Slow group, the response rate (RR) was significantly higher in patients treated with NIVO compared with IRI.

•

In the Rapid group, there was no significant difference in RR between the NIVO and IRI groups.

•

TGR and NL emergence during preceding treatment may be useful for drug selection.

Phase II study of cetuximab plus S-1/cisplatin therapy in Japanese patients with advanced gastric cancer

OBJECTIVE

We evaluated the efficacy and safety of first-line S-1 plus cisplatin in combination with cetuximab for Japanese patients with advanced gastric cancer, including gastroesophageal junction adenocarcinoma.

METHODS

This open-label, single arm, multicenter, phase 2 trial was conducted to assess first-line cetuximab plus S-1 plus cisplatin for advanced gastric cancer. A total of 40 patients from 10 centers were enrolled. Cetuximab was administered weekly, with the initial infusion at 400 mg/m2 and then 250 mg/m2 each subsequent week. S-1 plus cisplatin chemotherapy was concomitantly conducted in a 5-week cycle: S-1 (40-60 mg, adjusted for body surface area) was given twice daily for 3 consecutive weeks, followed by a 2-week rest period, and cisplatin (60 mg/m2) was given on day 8 of each cycle for a maximum of 8 cycles. Treatment continued until the occurrence of radiographically confirmed progressive disease, unacceptable toxicity or withdrawal of consent. The primary endpoint was the best overall response. Secondary endpoints included progression-free survival and safety.

RESULTS

A total of 40 patients were evaluable. One patient (2.5%) had a complete response; 15 patients (37.5%) had a partial response. The observed overall response rate according to the independent review committee was 40.0% (95% confidence interval, 24.9-56.7; P = 0.7043 [one-sided null hypothesis: overall response rate ≤ 43%]); median PFS was 5.6 months (95% confidence intervals, 4.2-8.3). No adverse events leading to death were reported during the study, and no specific safety concerns were observed.

CONCLUSIONS

Overall, the addition of cetuximab to S-1 plus cisplatin was well tolerated in patients with advanced gastric cancer but provided no additional clinical benefit in this study. ClinicalTrials.gov identifier: NCT01388790.

Evaluation of Definitive Chemoradiotherapy Versus Radical Esophagectomy in Clinical T1bN0M0 Esophageal Squamous Cell Carcinoma

BACKGROUND

The standard treatment for patients with clinical T1bN0M0 esophageal squamous cell carcinoma is radical esophagectomy. Definitive chemoradiotherapy is regarded as a treatment option, and recently, good clinical outcomes of this treatment have been reported. This study compared prognosis after definitive chemoradiotherapy with radical esophagectomy.

METHODS

From January 2011 to December 2019, 68 consecutive patients who were diagnosed clinical T1bN0M0 squamous cell carcinoma were enrolled and investigated retrospectively. Patients were classified into two groups whether treated by surgery or definitive chemoradiotherapy. Survival outcomes were compared, and subsequent therapies after recurrence were also investigated.

RESULTS

Among 68 patients, 39 patients underwent surgery and 29 patients received definitive chemoradiotherapy. No significant difference was noted in overall survival between the two groups. However, the rate of 5-year recurrence-free survival was significantly lower in definitive chemoradiotherapy group than that of surgery group (91.1 vs. 62.7%, hazard ratio 3.976, 95% confidence interval 1.076-14.696, p = 0.039). Patients who had local recurrence after definitive chemoradiotherapy received endoscopic submucosal dissection or photodynamic therapy as salvage therapies, which resulted in no disease progression and a good prognosis.

CONCLUSIONS

Definitive chemoradiotherapy may become a promising alternative therapy comparable with radical esophagectomy in patients with clinical T1bN0M0 esophageal squamous cell carcinoma. Early detection of recurrence by frequent follow-up after definitive chemoradiotherapy is important to control disease within local recurrence, and salvage therapy for local lesions could contribute to long-term survival.

Comparison of irinotecan and oxaliplatin as the first-line therapies for metastatic colorectal cancer: a meta-analysis

Background

Irinotecan (IRI) and oxaliplatin (Ox) are standard therapeutic agents of the first-line treatments for metastatic colorectal cancer (mCRC). Previous meta-analyses of randomized controlled trials (RCTs) showed that treatment with Ox-based compared with IRI-based regimens was associated with better overall survival (OS). However, these reports did not include trials of molecular targeting agents and did not take methods for the administration of concomitant drugs, such as bolus or continuous infusion of 5-fluorouracil, into account. A systematic literature review was performed to compare the efficacy and toxicity profiles between IRI- and Ox-based regimens as the first-line treatments for mCRC.

Methods

This meta-analysis used data from the Cochrane Central Register of Controlled Trials, PubMed, and SCOPUS. The primary endpoint was OS, and the secondary endpoints were progression-free survival (PFS), objective response rate (ORR), and adverse events (AEs).

Results

Nineteen trials involving 4571 patients were included in the analysis. No statistically significant difference was observed between the two groups in terms of OS, PFS, and ORR. There was no significant heterogeneity. Regarding ≥ grade 3 AEs, IRI-based regimens were associated with a high incidence of leukopenia, febrile neutropenia, and diarrhea. Moreover, there was a high incidence of thrombocytopenia and peripheral sensory neuropathy in patients who received Ox-based regimens. In a subgroup analysis, IRI combined with bevacizumab was correlated with a better PFS (HR = 0.90, 95% CI = 0.82–0.98, P = 0.02), but not with OS (pooled HR = 0.91, 95% CI = 0.80–1.03, P = 0.15).

Conclusion

Although the safety profiles of IRI- and Ox-based regimens varied, their efficacy did not significantly differ. The combination of anti-VEGF antibody and IRI was associated with better PFS compared with anti-VEGF antibody and Ox. Both regimens could be used as the first-line treatments for mCRC with consideration of the patients’ condition or toxicity profiles.

Efficacy and safety of 5-fluorouracil (5-FU) / levofolinate / irinotecan (FOLFIRI) for previously treated advanced pancreatic cancer (APC)

407

Background: 5-fluorouracil (5-FU) / levofolinate / irinotecan (FOLFIRI) is one of the preferred regimens for patients (pts) with advanced pancreatic cancer (APC) who received prior gemcitabine-based therapy in the National Comprehensive Cancer Network Guidelines. However, its survival benefit or safety in clinical practice is unclear. Methods: We retrospectively assessed the data of consecutive pts with APC who received FOLFIRI as a second or later-line treatment after gemcitabine-based therapy at Shizuoka Cancer Center between May 2014 and March 2020. Results: The characteristics of 102 pts included in this analysis were as follows: median age (range), 67 (39-78) y; male/female, 55/47; ECOG PS0/1/2, 21/72/9; the number of metastatic sites 0/1/2/3/4, 7/48/35/8/4; unresectable/recurrent, 84/18; UGT1A1 status wild/*6 or*28 heterozygous/homo or double-heterozygous/unknown, 40/40/5/17; treatment line of FOLFIRI 2nd/3rd/4th, 64/32/6. Previous treatment history according to the treatment line of FOLFIRI was as follows: 2nd-line, all patients received GEM-based regimen, GEM plus nanoparticle albumin bound paclitaxel in 63 pts (98.4%) and GEM in 1 (1.6%); 3rd, GEM-based and S1 in 20 (62.5%), GEM-based and 5-FU/levofolinate/oxaliplatin (FOLFOX) in 12 (37.5%); 4th, GEM-based, FOLFOX and S-1 or other agent in 5 (83.3%), 2 GEM-based regimens and S1 in 1 (16.7%). The median treatment cycle was 5 (range 1-55). The median treatment cycle according to the treatment line was as follows: 2nd-line, 7(1-55); 3rd, 4(1-14); 4th, 3.5(1-10). The initial dosage for each cytotoxic agent was as follows: bolus 5-FU injected/omited 72/30; continuous 5-FU 2400/2000/1200 mg/m2, 88/13/1; irinotecan 180/150/120/less than or equal to 100mg/m2, 27/59/13/3. The overall response rate (ORR) and disease control rate (DCR) were 5.9% and 52.9%, respectively. ORR and DCR according to the treatment line were as follows: 2nd-line, 9.3/64.1%; 3rd, 0/68.8%; 4th, 0/50.0%. At the median follow up 6.5 M, the median overall survival (OS) and progression free survival (PFS) were 6.6M and 3.1M, respectively. The median OS and PFS according to the treatment line were as follows: 2nd-line, 8.1/3.6M; 3rd, 5.1/2.1M; 4th, 6.6/2.0M. Adverse events (AEs) were observed in 70.8% pts. Grade 3 or higher AEs occurred in 27.2% pts [neutropenia in 26 (25.2%) pts, febrile neutropenia in 4 (3.9%) pts, nausea in 4 (3.9%) pts, decreased appetite in 3 (2.9%) pts]. No treatment related deaths were observed. Conclusions: FOLFIRI is well tolerated and effective especially in the second-line treatment for pts with gemcitabine-refractory APC.

Nivolumab in advanced esophageal squamous cell carcinoma (ATTRACTION-1/ONO-4538-07): Minimum of five-year follow-up

207

Background:ATTRACTION-1/ONO-4538-07 (AT-1), an open-label, single-arm, multicenter phase 2 clinical trial conducted in Japan, evaluated the clinical activity and safety of nivolumab in patients with advanced esophageal squamous cell carcinoma (ESCC) refractory/intolerant to fluoropyrimidine-, platinum-, and taxane-based chemotherapy. We previously reported the 2-year follow-up findings of AT-1, in which nivolumab demonstrated antitumor activity with a manageable safety profile for these patients. Here we report the final findings from AT-1 at a minimum follow-up of 5 years. Methods:Patients aged ≥20 years with an Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0-1 received 3 mg/kg nivolumab intravenously every 2 weeks in 6-week cycles until disease progression or unacceptable toxicity. The primary endpoint was centrally-assessed objective response rate (ORR), defined as the proportion of patients whose best overall response was either a complete or partial response. Secondary endpoints included overall survival (OS), investigator-assessed ORR, progression-free survival (PFS), change in tumor burden, time to response, time to disease progression, and duration of response. Results:Between February 25 and November 14, 2014, a total of 65 patients were enrolled. Sixty-four patients were evaluated for the efficacy, and all patients were evaluated for the safety. At the final database lock on August 6, 2020, 11 (17.2%, 95% confidence interval [CI] 9.9-28.2) of 64 patients had an objective response by central assessment. The median OS was 10.8 months (95% CI, 7.4-13.9), and the estimated 5-year OS rate was 6.3% (95% CI, 2.0-14.0). The median PFS was 1.5 months (95% CI, 1.4-2.8), and the estimated 5-year PFS rate was 6.8% (95% CI, 2.2-15.1). Treatment-related adverse events that occurred with a frequency of > 10% were diarrhea and rash. The presentation will include characteristics of long-term survivors as well as detailed efficacy and safety data of nivolumab. Conclusions:This final assessment represents the longest follow-up of patients with advanced ESCC treated with nivolumab. Nivolumab demonstrated continued long-term efficacy in these patients based on a minimum of 5-year long-term survival update of AT-1. Furthermore, no new safety signals with nivolumab were identified during long-term follow-up. These findings are consistent with those of nivolumab monotherapy for various types of cancer. Clinical trial information: No.142422.

Cumulative incidence of venous thromboembolism in patients with advanced cancer in prospective observational study

Venous thromboembolism (VTE) is frequently observed in patients with advanced cancer. The objective of this prospective observational study was to estimate, based on intensive screening, using computed tomography, lower‐extremity ultrasonography, and D‐dimer testing, the prevalence of VTE in patients with advanced cancer.

Patients with metastatic or locally advanced cancer without anticoagulant therapy, who were planning to receive chemotherapy during 4 weeks, were eligible. Evaluations of VTE were performed at pretreatment, 12 weeks, and 24 weeks after the start of chemotherapy. Primary endpoint was cumulative incidence of VTE for 24 weeks. Secondary endpoints included incidence of VTE (pretreatment, 12 weeks, and 24 weeks after the start of chemotherapy), VTE according to primary cancer site, symptomatic VTE, pulmonary thromboembolism (PE), and treatment of VTE.

We enrolled 860 patients with a median age of 68 years, including 34% female and 71% lung cancer. Cumulative incidence of VTE for 24 weeks was 22.6% (95% confidence interval: 19.8%–25.5%) (194 of 860 patients). Incidence of VTE was 11.3% pretreatment, 16.8% 12 weeks, and 14.1% 24 weeks. Symptomatic VTE was observed in 4.0% and PE in 1.0% of patients. By multivariate analysis, sex, D‐dimer level, and platelet count were independent risk factors of VTE for 24 weeks.

This large prospective observational study showed that cumulative incidence of VTE was high in advanced cancer patients, mainly lung cancer. Although most patients showed asymptomatic VTE, intensive screening of VTE may be considered in advanced cancer patients, especially in women with high level of D‐dimer and decreased platelet count (UMIN000015243).

Five-year follow-up of nivolumab treatment in Japanese patients with esophageal squamous-cell carcinoma (ATTRACTION-1/ONO-4538-07)

BACKGROUND

In the phase II ATTRACTION-1 study, nivolumab demonstrated a promising antitumor activity among Japanese patients with treatment-refractory advanced esophageal cancer. Here, we report the follow-up results of ATTRACTION-1 of > 5 years.

METHODS

We enrolled patients with esophageal cancer that was refractory or intolerant to a standard chemotherapy. Then, nivolumab (3 mg/kg) was administered every 2 weeks. The primary endpoint was a centrally assessed objective response rate.

RESULTS

Nivolumab was administered to 65 patients with esophageal squamous-cell carcinoma (ESCC). The centrally assessed objective response rate was 17.2%. The overall survival rates at 3 and 5 years were 10.9% and 6.3%, respectively. Three-year survivors tended to have more reduced target lesions. A total of 63.1% of the patients exhibited treatment-related adverse events, and no new safety signal was observed. Patients with select adverse events tended to have better overall survival than those without. No apparent chronological order was observed between the first response and the onset of select adverse events.

CONCLUSION

Our follow-up analysis of more than 5 years is currently the longest and is the first to demonstrate that nivolumab has long-term efficacy and safety for advanced ESCC.

The Safety and Survival Outcome of Hepatectomy with Combined Bile Duct Resection for Colorectal Liver Metastasis

BACKGROUND

Biliary confluence is sometimes involved in colorectal liver metastasis (CRLM), and therefore bile duct resection (BDR) is occasionally necessary for complete resection. However, the utility of hepatectomy with combined BDR is unclear. The safety and survival outcome of hepatectomy with combined BDR for CRLM was assessed.

METHODS

Patients who underwent hepatectomy for CRLM between 2002 and 2017 were identified from a prospectively compiled database. Postoperative outcomes were compared between patients undergoing hepatectomy alone and with combined BDR for CRLM.

RESULTS

A total of 734 patients who underwent hepatectomy for CRLM were included. Hepatectomy with combined BDR was performed in 16 (2.1%) patients. The postoperative complications rate (Clavien-Dindo ≥ 3) of patients undergoing hepatectomy with BDR was 31.2%, which was higher than that without BDR (P = 0.001) for CRLM. The mortality rate of surgery for CRLM was 0%. The 5- and 10-year relapse-free survival (RFS) rates for hepatectomy with BDR were 45.0% and 30.0%, respectively. Patients undergoing hepatectomy with BDR had a similar RFS to those without BDR for CRLM (P = 0.351). The 5- and 10-year overall survival (OS) rates for hepatectomy with BDR were 62.6% and 62.6%, respectively. Patients undergoing hepatectomy with BDR had a similar OS to those without BDR for CRLM (P = 0.738).

CONCLUSIONS

In conclusion, hepatectomy with combined BDR was a potentially feasible treatment option that obtained favorable survival outcomes in patients with invasion of the biliary confluence by CRLM, although BDR with hepatectomy for CRLM was associated with a high rate of morbidity.

The Negative Impact of Preoperative Chemotherapy on Survival After Esophagectomy for Vulnerable Elderly Patients with Esophageal Cancer

BACKGROUND

The standard treatment for patients 75 years of age or younger with cStage 2 or 3 esophageal cancer is preoperative chemotherapy followed by esophagectomy. The optimal treatment for elderly patients, especially those considered vulnerable, remains unclear.

METHODS

This study retrospectively reviewed the data for 42 patients ages 75-80 years with cStage 2 or 3 esophageal cancer who underwent esophagectomy between October 2002 and February 2019. The patients who received preoperative chemotherapy were compared with those who did not. The study also examined short- and long-term outcomes and the impact of preoperative chemotherapy on overall survival (OS) stratified by performance status (PS).

RESULTS

Of the 42 patients, 18 underwent esophagectomy without preoperative chemotherapy and 24 underwent esophagectomy after preoperative chemotherapy. A significantly greater proportion of the patients with PS 0 received preoperative chemotherapy than the patients with PS 1 (P =0.007). The multivariate analysis showed preoperative chemotherapy to be an independent negative prognostic factor for OS (hazard ratio [HR], 5.025; 95% confidence interval [CI] 1.136-22.222; P = 0.033). Subgroup analysis showed that preoperative chemotherapy had a significant negative impact on the OS of the patients with PS 1 (P < 0.001).

CONCLUSION

Preoperative chemotherapy was ineffective for the patients with PS 0 and had a significantly negative impact on the OS of the patients with PS 1. Preoperative chemotherapy should not be administered to patients 75 years of age or older with cStage 2 or 3 esophageal cancer.

Abstract 1974: Clonal and subclonal mutational landscapes in circulating tumor DNA in metastatic colorectal cancer: An exploratory analysis from the phase III PARADIGM study

Introduction: We performed an exploratory analysis of circulating tumor DNA (ctDNA) in patients (pts) with RAS wild-type (WT) chemotherapy-naïve stage IV metastatic colorectal cancer (mCRC) from the ongoing phase III PARADIGM study (NCT02394834). The clonal and subclonal mutational landscapes of RAS WT pts were analyzed using a mCRC-focused custom ctDNA sequencing panel.

Methods: Randomized pts (1:1) received mFOLFOX6 plus either panitumumab or bevacizumab. Pre-treatment plasma samples (DNA yield &gt;10ng/mL and &gt;10nM) were sequenced using the custom ctDNA panel (PlasmaSELECTTM-R 91, PGDx) to detect mCRC mutations, amplifications, and rearrangements in 90, 26, and 3 genes, respectively, as well as microsatellite instability (MSI), in 250kb targeted regions using stringent quality criteria. Pre-treatment archival tissue samples from 590 pts were analyzed by the Broad Institute Solid Tumor panel, which covered 1,072 genes with 7.3Mb targeted regions.

Results: Between May 29, 2015 and June 8, 2017, 823 pts were enrolled across 197 sites. Plasma samples were collected from 756 pts, with 747 (98.8%) samples meeting the quality criteria. The average total and distinct sequencing coverages were 34,200 and 5,865, respectively, with 49.1% of bases mapping to regions of interest. Mutation frequencies in ctDNA were generally consistent with those observed in RAS-WT TCGA CRC and rectal cancers (n=283), except for TET2 and DNMT3A potentially due to clonal hematopoiesis. Mutations in BRAF, APC, CTNNB1, PTEN, PIK3CA, and MSI-status observed in ctDNA were significantly different between left and right-sided tumors, consistent with known differences in tumor sidedness. In the 747 plasma samples, 4,072 mutations were observed; 1,871 had a mutant allele frequency (MAF) &lt;25% of the highest MAF in each sample (defined as subclonal) and 2,201 had a MAF above this threshold (defined as clonal). Clonal mutations were 77.5% concordant with mutations in corresponding tissue samples. Subclonal mutations showed 17.3% concordance between tissue and plasma, suggesting that tumor heterogeneity may result in subclonal mutations in ctDNA. Although pts with KRAS/NRAS mutations (G12, G13, A59, Q61, K117, A146) in archival FFPE tissue were not eligible for this study, 38 RAS mutations (58% subclonal) were observed in ctDNA of 32 pts, suggesting that sub-populations of tumor cells may have KRAS mutations in these cases. Patient-level subclonality analyses suggested that the fraction of subclonal mutations were higher in pts with metastases in ≥2 organ sites.

Conclusion: The validated ultra-deep plasma sequencing panel was concordant with tissue sequencing and detected tumor heterogeneity. The PARADIGM study will report the efficacy of anti-EGFR/VEGF therapies; post-treatment collection of ctDNA is ongoing. The relationship between therapeutic effects and clonal and subclonal mutational landscapes will be examined in the future. Funded by Takeda Pharmaceutical Company Limited, Tokyo, Japan. ClinicalTrial.gov number: NCT02394834

Citation Format: Katsuya Tsuchihara, Riu Yamashita, Takayuki Yoshino, Kohei Shitara, Jun Watanabe, Hirofumi Yasui, Hisatsugu Ohori, Manabu Shiozawa, Kentaro Yamazaki, Eiji Oki, Takeo Sato, Takeshi Naitoh, Yoshito Komatsu, Takeshi Kato, Kazunori Yamanaka, Ikuo Mori, Masamitsu Hihara, Junpei Soeda, Takeharu Yamanaka, Kiwamu Akagi, Atsushi Ochiai, Kei Muro, Victor E. Velculescu, Hiroyuki Uetake. Clonal and subclonal mutational landscapes in circulating tumor DNA in metastatic colorectal cancer: An exploratory analysis from the phase III PARADIGM study [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1974.

Prediction of S-1 adjuvant chemotherapy benefit in Stage II/III gastric cancer treatment based on comprehensive gene expression analysis

BACKGROUND

Studies to identify predictive biomarkers of adjuvant chemotherapy with S-1 after gastrectomy in Stage II/III gastric cancer patients have been done; however, more clarity and understanding are needed. Our aim in the present study was to identify biomarkers predicting benefit due to S-1 adjuvant chemotherapy using comprehensive gene expression analysis.

METHODS

We retrospectively analyzed 102 patients receiving adjuvant chemotherapy with S-1 and 46 patients not receiving S-1 adjuvant chemotherapy after gastrectomy for gastric cancer treatment between January 2014 and December 2016. Hierarchical clustering analysis was performed based on the gene expression data obtained using cDNA microarray. Differentially expressed genes (DEGs) were identified using thresholds of absolute fold changes of > 4.0 and a false discovery rate P value of < 0.01. Gene Ontology (GO) analysis and GO network visualization were performed using the ClueGO app in Cytoscape.

RESULTS

Hierarchical clustering analysis in patients treated with S-1 adjuvant chemotherapy revealed two clusters with favorable and unfavorable survival outcomes. We identified 147 upregulated DEGs and 192 downregulated DEGs in the favorable outcome group. GO analysis to identify significantly upregulated genes showed enrichment in immune-related genes and GO terms. Upregulation of these immune-related genes was not associated with survival in patients not receiving S-1 adjuvant chemotherapy.

CONCLUSIONS

The upregulation and enrichment of immune-related genes and GO terms may be predictive biomarkers in patients who would benefit from adjuvant S-1 chemotherapy to treat Stage II/III gastric cancer.

Impact of tumour growth rate during preceding treatment on tumour response to regorafenib or trifluridine/tipiracil in refractory metastatic colorectal cancer

Background

Although regorafenib (REG) and trifluridine/tipiracil (FTD/TPI) have been recognised as standard treatments in metastatic colorectal cancer (mCRC), the best option remains unclear. Pretreatment tumour growth rate (TGR) is associated with radiotherapeutic efficacy in laryngeal cancer. However, no reports are available on the association between TGR during preceding treatment and the efficacy of REG or FTD/TPI.

Patients and methods

We retrospectively analysed the data of consecutive mCRC patients treated with REG or FTD/TPI and classified them into slow-growing or rapid-growing (SG or RG) groups according to TGR and emergence of new lesion (NL+) or their absence (NL−) during preceding treatment period [SG: NL− with low TGR (<0.33%/day); RG: NL+ or high TGR (≥0.33%/day)].

Results

A total of 244 patients (RG/SG, 133/111; REG/FTD/TPI, 132/112) were eligible. The RG proportion with a long duration from first-line chemotherapy and the SG proportion with elevated alkaline phosphatase were higher in REG, whereas the SG proportion with performance status 2 was higher in FTD/TPI. The disease control rates (DCRs) were similar between REG and FTD/TPI (24%/30%; OR: 0.74; p=0.44; adjusted OR: 0.73; p=0.47) in the RG, whereas the DCR was significantly higher for FTD/TPI than for REG (47%/26%; OR: 2.56; p=0.029; adjusted OR: 3.38; p=0.01) in the SG.

Conclusions

TGR and NL during preceding treatment may be helpful for drug selection in refractory mCRC patients to be treated with REG or FTD/TPI. However, further studies are needed to confirm the value of TGR for drug selection.

Comprehensive assessment of multiple tryptophan metabolites as potential biomarkers for immune checkpoint inhibitors in patients with non-small cell lung cancer

Purpose

Tryptophan metabolites have immunomodulatory functions, suggesting possible roles in cancer immunity.

Methods

Plasma tryptophan metabolites were measured using liquid chromatography/mass spectrometry before immune checkpoint inhibitors (ICIs) in patients with non-small cell lung cancer (NSCLC).

Results

The 19 patients with NSCLC had significantly lower levels of tryptophan (p = 0.002) and xanthurenic acid (p = 0.032), and a significantly higher level of 3-hydroxyanthranilic acid (3-HAA) (p = 0.028) compared with the 10 healthy volunteers. The patients achieving objective responses had significantly lower levels of 3-HAA than those who did not (p = 0.045). Receiver operating characteristic analyses determined that the cutoff value of 3-HAA for objective response was 35.4 pmol/mL (sensitivity: 87.5% and specificity: 83.3%). The patients with 3-HAA < 35.4 pmol/mL had significantly longer median progression-free survival (7.0 months) than those without (1.6 months, p = 0.022).

Conclusions

Tryptophan metabolites may have a potential for predicting the efficacy of ICIs.

Registration number

University Hospital Medical Information Network Clinical Trial Registry 000026140.

Electronic supplementary material

The online version of this article (10.1007/s12094-020-02421-8) contains supplementary material, which is available to authorized users.

Randomized, Phase II Study of Trastuzumab Beyond Progression in Patients With HER2-Positive Advanced Gastric or Gastroesophageal Junction Cancer: WJOG7112G (T-ACT Study)

PURPOSE

This study evaluated the continuous use of trastuzumab beyond progression (TBP) in human epidermal growth factor receptor 2 (HER2)-positive advanced gastric or gastroesophageal junction (G/GEJ) cancer.

PATIENTS AND METHODS

Patients with HER2-positive advanced G/GEJ cancer refractory to first-line chemotherapy with trastuzumab in combination with fluoropyrimidine and platinum were eligible. Patients were randomly assigned to the paclitaxel (80 mg/m2, days 1, 8, and 15, every 4 weeks) or paclitaxel with trastuzumab (PT; initially 8 mg/kg followed by 6 mg/kg, every 3 weeks) arms. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), response rate, and safety. Biomarkers such as HER2 expression status in tumor tissue after first-line treatment, HER2 amplification evaluated in serum cell-free DNA, and soluble HER2 levels were analyzed.

RESULTS

Overall, 91 patients were allocated to the paclitaxel (n = 46) and PT (n = 45) arms. The median PFS in the paclitaxel and PT arms was 3.2 and 3.7 months, respectively (hazard ratio [HR], 0.91; 80% CI, 0.67 to 1.22; P = .33), and the median OS in both arms was 10 months (HR, 1.2; 95% CI, 0.75 to 2.0; P = .20). The overall response rates in the paclitaxel and PT arms were 32% and 33%, respectively ( P = 1.00), and safety was comparable between the 2 arms. On exploratory analyses, HER2 positivity of tumor tissues was lost after first-line chemotherapy in 11 (69%) of 16 patients whose tumor tissues were available, and circulating HER2 DNA amplification was detected in 41 (60%) of 68 patients. However, no biomarkers associated with efficacy of TBP were found.

CONCLUSION

The TBP strategy failed to improve PFS in patients with HER2-positive advanced G/GEJ cancer, and no beneficial biomarkers were found.

Chemoradiotherapy for high-risk stage II laryngeal cancer

BACKGROUND

Definitive radiotherapy (RT) for stage II laryngeal cancer is known to be less effective for locoregional control and survival (LRCS) in patients with high-risk factors (e.g., subglottic extension, impaired cord mobility, or bulky tumor size) than in low-risk patients. The purpose of this study was to evaluate the safety and efficacy of chemoradiotherapy (CRT) for stage II laryngeal cancer patients with high-risk factors METHODS: Sixty-five consecutive patients with stage II laryngeal cancer who received radiotherapy (RT) alone or CRT were retrospectively analyzed. The patients were classified into three groups: RT, low risk (RT-low, n = 26); RT, high risk (RT-high, n = 25); and CRT, high risk (CRT-high, n = 14).

RESULTS

The glottis was the most common primary tumor site in all groups. Most patients in the CRT-high group received platinum-based CRT. The 5-year locoregional control and survival (LRCS) rates were 88.3, 44.2, and 85.7% in the RT-low, RT-high, and CRT-high groups, respectively. In multivariate analysis, high-risk disease and CRT were significantly associated with 5-year LRCS rates.

CONCLUSION

CRT may provide better locoregional control than RT alone in high-risk stage II laryngeal cancer.

Association between dexamethasone treatment and alterations in serum concentrations of trace metals

Previously, a significant elevation in the serum levels of iron (Fe) was observed within a few days after the initiation of cisplatin (CDDP)-based chemotherapy. To clarify the underlying mechanisms, the serum concentration of hepcidin, a negative regulator of Fe release, was determined in the clinical samples obtained from six patients with cancer. The result showed that the serum concentration of hepcidin in patients receiving CDDP-based chemotherapy was significantly increased after 4-6 days of treatment, in comparison to the baseline level, suggesting that aforementioned excessive systemic Fe was not explained by the change of serum hepcidin level. All these patients received antiemetic premedication. We next evaluated of the effects of Pt-containing drugs and prophylactic antiemetic dexamethasone medication on the serum concentration of trace metals in mice, and on the hepatic and renal concentration of trace metals. The serum concentrations of Fe, Cu, and Zn in the CDDP-treated and oxaliplatin-treated mice were not significantly altered in comparison to those of the vehicle-treated control group. The serum concentrations of Fe, Cu, and Zn were increased after 24 h of dexamethasone treatment, compared to those of the control group (P < 0.05). The hepatic concentration of Mn was significantly reduced, whereas those of Fe and Cu inclined to diminish. The present findings suggest that dexamethasone can partly contribute to the changes in the serum concentrations of trace metals during anticancer chemotherapy.

Long-term efficacy and predictive correlates of response to nivolumab in Japanese patients with esophageal cancer

The long-term efficacy of nivolumab in esophageal squamous cell carcinoma and its association with disease biomarkers are currently not well known. Therefore, we investigated the association in Japanese patients with treatment-refractory advanced esophageal cancer who participated in an open-label, single-arm, multicenter phase II study. Patients received nivolumab 3 mg/kg i.v. every 2 weeks until disease progression or unacceptable toxicity, and were followed up for 2 years after the initial dosing of the last patient. Archival tissue samples were collected before treatment and analyzed for programmed death ligand-1 (PD-L1) and CD8⁺ status of tumors and tumor-infiltrating lymphocytes (TILs) and human leukocyte antigen class 1. Efficacy end-points included objective response rate (ORR), overall survival (OS), progression-free survival (PFS), time to response, and duration of response. Of 65 enrolled patients (83% male), 64 were evaluable for efficacy and 41 (63%) for biomarkers. The ORR, median OS, and survival rate were 17.2%, 10.78 months, and 17.2%, respectively. Time to response was 1.45 months and duration of response was 11.17 months. The PD-L1 positivity of tumor cells was possibly associated with better PFS (2.04 vs 1.41 months, cut-off 1%) and OS (11.33 vs 6.24 months, cut-off 1%). Median OS was prolonged in patients with a median number of TILs greater than 63.75% vs 63.75% or less (11.33 vs 7.85 months). Nivolumab showed continued long-term efficacy, as seen by the stability of PFS and OS, in Japanese patients with esophageal squamous cell carcinoma. Further investigation of PD-L1 tumor expression and TILs as potential biomarkers for predicting patients likely to benefit from nivolumab therapy is warranted.

Appropriate Candidates for Salvage Esophagectomy of Initially Unresectable Locally Advanced T4 Esophageal Squamous Cell Carcinoma

BACKGROUND

Standard treatment for unresectable locally advanced esophageal cancer is definitive chemoradiotherapy (dCRT). Although salvage esophagectomy is the only curative treatment available following dCRT failure, the appropriate candidates for salvage esophagectomy remain unclear.

PATIENTS AND METHODS

Three hundred seventeen patients who underwent dCRT from April 2004 to December 2016 were stratified into three study groups-a complete response (CR) group, chemotherapy or best supportive care (BSC) group, and salvage esophagectomy group-and compared. We also investigated the clinical outcomes and prognostic factors of salvage esophagectomy.

RESULTS

Seventy-one patients (22.4%) achieved CR after dCRT, 18 patients (5.7%) underwent salvage esophagectomy, and 228 patients (71.9%) underwent palliative chemotherapy or BSC. The 5-year overall survival (OS) rates of the CR group, salvage esophagectomy group, and chemotherapy or BSC group were 83.0%, 51.6%, and 1.3%, respectively. Salvage esophagectomy recipients had a worse OS rate than CR patients (p < 0.001) but a better OS rate than those in the chemotherapy or BSC group (p < 0.001). Incomplete resection was the only significant variable associated with poor OS on univariate Cox proportional-hazards analysis (hazard ratio: 7.633, 95% confidence interval: 1.692-34.482; p = 0.008). Patients with tumors in the upper thoracic esophagus were more likely to undergo incomplete resection (p = 0.011).

CONCLUSIONS

Patients who achieve R0 resection are good candidates for salvage esophagectomy regardless of their response to dCRT. Those with upper thoracic esophageal tumors are at risk of incomplete resection; careful attention is required when considering these patients for salvage esophagectomy.

Risk factors for aspiration pneumonia during concurrent chemoradiotherapy or bio-radiotherapy for head and neck cancer

Background

Aspiration pneumonia is one of the most important side effects of chemoradiotherapy (CRT) and bio-radiotherapy (BRT) in patients with head and neck cancer (HNC). Aspiration pneumonia can lead to cancer-related mortality in HNC patients. However, the relationship between aspiration pneumonia occurring during CRT or BRT for HNC and treatment outcomes in HNC patients is not well characterized. In this study, we assessed the influence of aspiration pneumonia on treatment outcomes and sought to identify the clinical risk factors for aspiration pneumonia during definitive CRT and BRT in HNC patients.

Methods

We retrospectively assessed the data pertaining to patients with locally advanced HNC who received definitive CRT or BRT at the Shizuoka Cancer Center between August 2006 and December 2016.

Results

Among the 374 HNC patients who received CRT or BRT, 95 (25.4%) developed aspiration pneumonia during treatment. Aspiration pneumonia was significantly associated with therapeutic response to CRT or BRT (multivariate adjusted odds ratio for complete response, 0.52, p = 0.020) and poor overall survival (multivariate adjusted hazard ratio for overall survival, 1.58, p = 0.024). The multivariate analyses identified four independent factors for aspiration pneumonia: poor oral hygiene, high N-classification, hypoalbuminemia before treatment, and inpatient treatment.

Conclusions

Aspiration pneumonia occurring during CRT or BRT has a detrimental effect on the therapeutic response and survival of HNC patients. Careful attention should be paid to these risk factors for aspiration pneumonia in HNC patients undergoing CRT or BRT.