Immune checkpoint inhibitors and tyrosine kinase inhibitors in patients with advanced hepatocellular carcinoma: Does the sequence matter?

INTRODUCTION

Combination therapy with immune checkpoint inhibitor (ICI) and antivascular endothelial growth factor (anti-VEGF) is currently the first line treatment for advanced hepatocellular carcinoma (aHCC). However, there are many patients who may not be able to receive combination therapy due to underlying comorbidities or resource limitations. For these patients, systemic treatment options include single agent tyrosine kinase inhibitors (TKIs) or ICI monotherapy. However, whether an optimal sequence of systemic therapy exists remains unknown. We aim to explore the impact of sequencing of TKI and ICI therapy in terms of response rates and to examine the safety of their use in sequential order.

METHODS

Patients with aHCC treated with both ICI and TKI between December 30, 2013 and June 13, 2018 were retrospectively identified. Patients were classified into two groups: those who received TKI in the first-line (TKI1), followed by ICI (ICI2) and those who received ICI (ICI1) in the first-line followed by TKI (TKI2). The primary objective of the study was to identify differences in objective response rate (ORR) and disease control rate (DCR), as evaluated based on response evaluation criteria in solid tumor v1.1 for TKI1, TKI2, ICI1, and ICI2. Secondary objectives included comparison of progression free survival (PFS) for each line of therapy, overall survival (OS) and adverse events (AEs).

RESULTS

Twenty-seven and 23 patients were classified into group 1 and 2, respectively. Objective response rates of TKI1 and TKI2 were 3.8% and 17.6%, respectively (p = .28); DCR to TKI1 versus TKI2 was 23.1% versus 35.3% (p = .49). ORRs of ICI1 and ICI2 were 8.7% and 14.3%, respectively (p = .66); DCR to ICI2 versus ICI1 was 56.5% versus 42.9% (p = .37). Median PFS was not significant between TKI1 and TKI2 (PFS 3.06 versus 1.61 months, p = .097) as well as between ICI2 and ICI1 (PFS 1.84 versus 2.37 month, p = .32). Median OS was also not significantly different between both groups (OS 20.63 versus 13.93 months, p = .20) on univariable and multivariable analysis (OS adjusted hazard ratio [HR] 2.07, 95% CI .83-5.18, p = .118). The proportion of patients who experienced adverse events of any grade was similar in both groups (TKI1 59.3% versus TKI2 52.2%; ICI1 78.3% versus ICI2 70.4%).

CONCLUSION

Our study suggests that the sequence of TKI versus ICI therapy in patients with aHCC may not matter, given similar efficacy and toxicity profile when either agent is received in the first or second-line setting. This finding is of value in the real-world setting, where patients may be frail or have comorbidities that render them unable to tolerate combination therapy (ICI and TKI/anti-VEGF). For these patients, sequential exposure to both classes of drugs (ICI and TKI) may be a suitable option.

Impact of Immune-Related Adverse Events on Efficacy of Immune Checkpoint Inhibitors in Patients with Advanced Hepatocellular Carcinoma

INTRODUCTION

Development of immune-related adverse events (irAEs) has been associated with enhanced efficacy with the use of immune checkpoint inhibitors (ICIs). It remains unknown whether such an association exists in advanced hepatocellular carcinoma (aHCC). This study aims to evaluate the association between irAEs and ICI efficacy in patients with aHCC.

METHODS

We performed a retrospective cohort study on patients with aHCC who received at least one dose of an ICI between May 2015 and November 2019 at the National Cancer Centre Singapore. The primary study objectives were to compare the overall survival (OS) and progression-free survival (PFS) between patients with and without irAEs. Complementary multivariable landmark analyses were performed at the 6-week and 12-week landmarks. Data cutoff was December 31, 2020.

RESULTS

One hundred and sixty-eight patients were included. Median age was 69 years, 85.7% were male, 57.7% had hepatitis B infection, 60.7% had ECOG 0, and 78.0% had Child-Pugh A liver cirrhosis. 82.7% received ICI monotherapy, while 17.3% received ICI in combination. Development and severity of irAE were correlated with survival. The median PFS for grade ≥3 irAE versus grades 1-2 irAE versus no irAE was 8.5 versus 3.6 versus 1.3 mths (p < 0.001). The median OS for grade ≥3 irAE versus grades 1-2 irAE versus no irAE was 26.9 versus 14.0 versus 4.6 mths (p < 0.001). Patients with ≥2 irAEs had a significantly longer OS on multivariable analysis (adjusted hazard ratio [aHR]0.35, p < 0.001). The presence of grade ≥3 irAEs was associated with a significantly longer OS on the multivariable analysis at the 6-week landmark (aHR0.34, p = 0.030) and 12-week landmark (aHR0.28, p = 0.011). The use of systemic corticosteroids in patients with irAE was associated with a trend toward a longer OS (20.7 vs. 14.3 mths, p = 0.064).

CONCLUSION

Our study suggests that the presence of all-grade irAEs may be a potential prognostic biomarker in patients with aHCC treated with ICI. Patients with more severe irAEs and multisystem involvement have better prognosis. The prompt use of systemic corticosteroids to treat patients with irAEs is key to ensure the best long-term outcomes for these patients.

Molecular Imaging and Therapy of Liver Tumors

Liver cancer is one of the top leading causes of mortality worldwide. Conventional imaging using contrast enhanced CT and MRI are currently the mainstay of oncologic imaging of the liver for the diagnosis and management of cancer. In the past two decades, especially since the advent of hybrid imaging in the form of PET/CT and SPECT/CT, molecular imaging has been increasingly utilized for oncologic imaging and the variety of radionuclide probes for imaging liver cancers have been expanding. Beyond the usual workhorse of FDG as an oncologic tracer, there is a growing body of evidence showing that radiolabeled choline tracers, C-11 acetate and other new novel tracers may have increasing roles to play for the imaging of liver tumors. On the therapy front, there have also been advances in recent times in terms of targeted therapies for both primary and secondary liver malignancies, particularly with transarterial radioembolization. The concept of theranostics can be applied to transarterial radioembolization by utilizing a pretreatment planning scan, such as Tc-99m macroaggregated albumin scintigraphy, coupled with post treatment imaging. Radiation dose planning by personalized dosimetric calculations to the liver tumors is also being advocated. This article explores the general trends in the field of nuclear medicine for the imaging and treatment of liver cancer above and beyond routine diagnosis and management.

Real-world efficacy and safety of immune checkpoint inhibitors in advanced hepatocellular carcinoma: Experience of a tertiary Asian center

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Background: Immune checkpoint inhibitor (ICI) use in advanced hepatocellular carcinoma (HCC) is increasing. Real-world data on efficacy and safety however is lacking, more so when used in patients who fall out of standard clinical trial criteria. Methods: We conducted a retrospective review of all patients with advanced HCC seen at our centre who received at least one dose of an ICI between May 2015 - June 2018. Data cutoff was 31 Dec 2018. Responses were evaluated using RECIST v1.1 criteria. Results: 114 patients fulfilled inclusion criteria. Median age was 66 years and 88.6% were male. 96.5% had an ECOG PS of 0 – 1. 64.9% received an ICI within a clinical trial setting. 62.3% received monotherapy ICI. 19.6% of patients had Child-Pugh B disease on initiation of ICI, and 69.3% had an ALBI Grade of 2. 50.0% were known to have hepatitis B and 11.4% had hepatitis C. Baseline HBV VL ranged from undetectable to 8210000 IU/mL. 30.7% received prior systemic treatment, most commonly sorafenib (82.9%). Over a median follow-up duration of 5.7 months (0.03 - 42.4), ORR was 18.4%, and disease control rate (DCR) was 51.8%. Median PFS was 2.6 months (1.7 - 3.9), and median OS was 13.9 months (7.0 - 16.2). 5 patients (23.8%) had response duration of more than 18 months. 35.1% received further systemic therapy after ICI. On multivariable analyses, age ≥ 65 years, higher albumin level and lower bilirubin level were associated with increased OS. 68.0% of patients experienced adverse events (AEs) of any grade, 12.0% of these being grade 3 - 4. No grade 5 adverse events were observed. Use of antiviral therapy was associated with a lower risk of hepatic AEs (p = 0.04) whilst high baseline HBV VL was not associated with an increased risk of reactivation or hepatic AEs. Conclusions: In the real-world setting, responses and adverse event profiles to ICI use are comparable to those observed in clinical trials despite a more heterogenous population base. The expansion of indications for ICI use in advanced HCC beyond current approvals warrants greater study.

Prognostic and predictive value of circulating tumour DNA (ctDNA) by amplicon-based next generation sequencing (NGS) of advanced pancreatic cancer (APC) in a phase I trial of oxaliplatin capecitabine and irinotecan (OXIRI) triplet chemotherapy

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Background: Tumoral KRAS mutations (KRAS mt) are detected in ~80% of APC and associated with a negative prognosis. Digital droplet PCR (ddPCR) has high sensitivity for circulating KRASmtbut narrower gene coverage. NGS using hybrid-capture methods has reported ctDNA KRASmtin ~30% of patients (pt). We previously presented clinical results of the Phase I trial of OXIRI (GI ASCO 18 #411). We now present the first prospective evaluation of ctDNA in APC by an amplicon-based NGS approach in this Phase I trial. Methods: Paired ctDNA and CA19-9 samples were taken at baseline, C2D1, C3D1 and end of trial. A targeted panel with error-correction (Lucence Diagnostics) was used to detect for mtin KRAS, TP53, SMAD4, CDKN2A, CTNNB1, GNAS, APC and MYC. CT scans were performed every 2 cycles. Survival curves by Kaplan Meier were compared by mutational status, ctDNA and CA19-9 response using the log-rank test. Spearman correlation of ctDNA and CA19-9 changes was performed. Results: ctDNA mtwas detected at baseline in 19/23 (83%) samples, comprising KRAS 17/23 (73%), TP53 (61%), SMAD4 (48%) and CDKN2A (30%). KRAS mtand SMAD4 mt conferred a negative prognosis for overall survival with a hazard ratio of 4.2 (CI: 1.6-10.4; p = 0.01) and 2.8 (CI: 0.9-8.65; p = 0.01) respectively. Drop in ctDNA and CA19-9 was associated with a trend for longer progression free survival at C2D1 (both) and C3D1 (ctDNA only). Radiological partial response (PR) was associated with lower ctDNA in 5/5 pt and CA 19-9 in 4/5 pt. Decrease in ctDNA and CA19-9 was associated with disease control (PR/SD) at C2D1 in 11/14 pt and 10/10 pt; at C3D1 in 11/12 pt and 6/7 respectively. No significant correlation between the amplitude of CA19-9 and ctDNA changes was found. Conclusions: ctDNA could be detected in 83% of pts of whom KRAS mtrates were similar to reports using tissue NGS. Determination of RAS mtand SMAD4 mtin ctDNA may aid in the prognostication of pts and decrease in ctDNA levels may predict for treatment benefit, similar in extent to CA 19-9. This may be particularly useful in non-CA19-9 secreting APC as an adjunct to imaging. Clinical trial information: NCT02368860.

What is the value of third-line chemotherapy in advanced gastroesophageal cancer? A 5-year retrospective analysis at a single center

AIM

The survival benefit of using a non-cross resistant second-line chemotherapy in the third-line setting in metastatic gastroesophageal cancer is unproven. We evaluated the utility of third-line chemotherapy in patients treated at a single institution.

METHODS

Between 2010 and 2014, efficacy and toxicity data of patients who received three or more lines of systemic therapies for metastatic gastroesophageal adenocarcinoma at the National Cancer Centre Singapore was retrospectively analyzed.

RESULTS

Thirty-two (6%) patients received three or more lines of chemotherapy. The median age and ECOG performance status were 59 years (36-82) and 1 (0-2), respectively. Majority of patients (88%) had tumor located in the stomach and 13 patients (41%) had diffuse histology or poorly cohesive or signet ring cells. Four (12%) patients had HER2-positive disease. Prior therapy was platinum (100%), fluoropyrimidine (97%), taxane (63%), irinotecan (28%), anthracycline (13%) and ramucirumab (3%). Third-line therapy consisted of 24 (75%) monotherapy, 6 (19%) doublet, 1 (3%) triplet chemotherapy and 1 (3%) clinical trial. Monotherapy irinotecan (44%) was most common, followed by docetaxel (19%) and paclitaxel (9%). Of 22 patients evaluable for response, there was 1 (5%) partial response, 9 (41%) stable disease. Median overall survival was 18.3 weeks (4.3-65.1). Of 30 patients evaluable for toxicities, 17 (57%) experienced at least one grade 3 or 4 toxicities.

CONCLUSION

The benefit of using non-cross resistant second-line regimens as third-line chemotherapy was small with moderate toxicity. Newer agents such as nivolumab or TAS-102 or clinical trial may be preferred.

Circulating tumor DNA as a potential marker of adjuvant chemotherapy benefit following surgery for localized pancreatic cancer

BACKGROUND

In early-stage pancreatic cancer, there are currently no biomarkers to guide selection of therapeutic options. This prospective biomarker trial evaluated the feasibility and potential clinical utility of circulating tumor DNA (ctDNA) analysis to inform adjuvant therapy decision making.

MATERIALS AND METHODS

Patients considered by the multidisciplinary team to have resectable pancreatic adenocarcinoma were enrolled. Pre- and post-operative samples for ctDNA analysis were collected. PCR-based-SafeSeqS assays were used to identify mutations at codon 12, 13 and 61 of KRAS in the primary pancreatic tumor and to detect ctDNA. Results of ctDNA analysis were correlated with CA19-9, recurrence-free and overall survival (OS). Patient management was per standard of care, blinded to ctDNA data.

RESULTS

Of 112 patients consented pre-operatively, 81 (72%) underwent resection. KRAS mutations were identified in 91% (38/42) of available tumor samples. Of available plasma samples (N = 42), KRAS mutated ctDNA was detected in 62% (23/37) pre-operative and 37% (13/35) post-operative cases. At a median follow-up of 38.4 months, ctDNA detection in the pre-operative setting was associated with inferior recurrence-free survival (RFS) [hazard ratio (HR) 4.1; P = 0.002)] and OS (HR 4.1; P = 0.015). Detectable ctDNA following curative intent resection was associated with inferior RFS (HR 5.4; P < 0.0001) and OS (HR 4.0; P = 0.003). Recurrence occurred in 13/13 (100%) patients with detectable ctDNA post-operatively, including in seven that received gemcitabine-based adjuvant chemotherapy.

CONCLUSION

ctDNA studies in localized pancreatic cancer are challenging, with a substantial number of patients not able to undergo resection, not having sufficient tumor tissue for analysis or not completing per protocol sample collection. ctDNA analysis, pre- and/or post-surgery, is a promising prognostic marker. Studies of ctDNA guided therapy are justified, including of treatment intensification strategies for patients with detectable ctDNA post-operatively who appear at very high risk of recurrence despite gemcitabine-based adjuvant therapy.

Rogaratinib treatment of patients with advanced urothelial carcinomas prescreened for tumor FGFR mRNA expression

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Background: Activation of FGFR signaling is involved in a variety of malignancies including advanced urothelial cancer (UC). Rogaratinib is an oral pan-FGFR kinase inhibitor. We report here the results from a phase I expansion cohort in UC patients prescreened for FGFR1-3 mRNA expression levels and activating mutations. (NCT01976741) Methods: Patients with advanced urothelial carcinomas were selected based on high FGFR1-3 mRNA expression in biopsy specimens. Selected patients were treated with rogaratinib 800mg twice daily until tumour progression, untolerable toxicity, or withdrawal. Tumor response was assessed by RECIST, v1.1. Adverse events were reported using CTCAE v4.03 criteria. Results: A total of 219 UC patients were prescreened for FGFR1-3 mRNA expression levels and FGFR3 activating mutations, with 99 samples (45%) found to be FGFR-positive. Of those, 87% of samples were positive for FGFR3 mRNA, 5% for FGFR1 mRNA and 8% were double FGFR mRNA-positive (FGFR1/2, 1/3 or 2/3). Frequency of FGFR3 activating mutations in UC samples was 7%, all of which also had high FGFR3 mRNA. Fifty two patients (median prior line of treatment 2) started treatment and 51 were evaluable for response. Rogaratinib was generally well tolerated and AEs manageable with dose modification. The most common AEs were diarrhea (49%) and hyperphosphatemia (49%). Objective response rate (ORR) was 24% (12/51; all PRs) and disease control rate (DCR) was 73% (37/51). Eleven of 12 pts with a PR were positive for FGFR3 mRNA, 5 of whom also had FGFR3 mutations, and one patient was positive for FGFR1 mRNA. Ten FGFR-positive UC patients had prior immuno-oncology (I/O) treatment, 9 of whom had progressive disease as best response. For these 10 patients the ORR was 30% and the DCR 80%. Conclusions: Selection of pts for treatment with rogaratinib based on FGFR mRNA expression levels was feasible and identified drug-sensitive patients with and without underlying DNA alterations. Rogaratinib had a favorable safety profile and showed promising anti-tumor activity in UC patients. Responses and disease stabilization were observed with rogoratinib in UC pts refractory to prior I/O treatment. Clinical trial information: NCT01976741.

A phase II open-label, single-centre, non-randomized trial of Y90 transarterial radioembolization in combination with nivolumab in Asian patients with intermediate stage hepatocellular carcinoma: An immunological study of radioembolization in combination with anti-PD1 therapy in HCC

TPS542

Background: In recent years, Yttrium-90 (Y90) trans-arterial radioembolization (TARE) has emerged as a therapeutic option for intermediate stage hepatocellular carcinoma (HCC). Cancer immunotherapy targeting tumour immune evasion has shown remarkable successes in various cancers. Nivolumab, an immune checkpoint inhibitor of programmed death 1 (PD1), has demonstrated encouraging activity in advanced stage HCC. Similarly, chronic hepatitis B virus (HBV) infection, a strong risk factor for HCC, is characterized by immune escape mechanisms. We hypothesize that TARE will stimulate tumor and/or HBV specific T cell responses that can be boosted using nivolumab. We thus propose an open label phase 2 trial investigating the combination of TARE with nivolumab in BCLC intermediate stage HCC. Methods: Eligible patients (pts) have ECOG performance status ≤ 2, Child-Pugh A score, intermediate stage HCC planned for TARE according to institutional practice with adequate organ function. Pts will be treated with TARE followed by nivolumab 240mg, 21 days after TARE and every 2 weeks thereafter. Pre- and on-treatment tumor biopsies will be taken. Primary end-point is response rate (RR) of combinational TARE and nivolumab. Key secondary end points are: progression free survival, overall survival, safety and quality of life using FACT-HEP score and EORTC QLQ-C30. Exploratory objectives are to evaluate how tumor PD L-1 expression, HCC mutational burden and blood lymphocyte activation/phenotypic profiles correlate with tumor response. Where possible, serial changes in antigen-specific T cell responses to HBV and/or tumour antigens will also be assessed. This study aims to enroll 40 pts as calculated using the Simon two-stage optimal design with 80% power and one sided significance level of 0.05. This will assess whether the addition of nivolumab improves the RR of TARE at 8 weeks from 21% to 41%. Patient accrual was initiated in December 2016 and as of September 2017, 9 pts have been treated. Clinical trial information: 03033446.

Oxaliplatin (OX), chronomodulated capecitabine, and UGT1A1 genotype-directed dosing of irinotecan (IR) triplet chemotherapy (OXIRI) in patients (pts) with advanced pancreatic cancer (APC)

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Background: The FOLFIRINOX regimen is highly active in APC, but its use is limited by toxicity. Irinotecan (IR) toxicity is correlated with UGT1A1 genotype status and chronomodulated delivery of fluoropyrimidines may reduce toxicity and increase efficacy. We have presented the dose escalation (DES) of OXIRI. In dose expansion (DXP), several pts required dose reduction after cycle 1 and we evaluated a lower starting dose. We now present data of the recommended Phase II dose (RP2D) and DES combined. Methods: Pts with APC and ECOG performance status ≤2, adequate organ function were enrolled. Previous OX or IR exposure was disallowed. During DES, APC pts homozygous for UGT1A1*6/*6 or UGT1A1*28/*28 were excluded. During DXP, only pts progressing on ≥ 1 line prior chemo was allowed and IR was dosed according to UGT1A1 genotype. At RP2D, pts received iv OX 37.5mg/m2 and IR 50mg/m2 on D1, 8 and po capecitabine 2650mg once at midnight on D1-14 every 21D until progression. Results: A total of 25 pts were enrolled, 17 in DES and 8 in DXP, 21 had metastatic and 4 had locally advanced APC. Male:Female 11:14, median (range) age and ECOG PS was 65yrs (50-77) and 0 (0-1) respectively. Pts with 0, 1 or 2 lines of prior chemo were 4 (16%) , 14 (56%) and 7(28%) respectively. Grade 3/4 AEs (≥5%) related to OXIRI were neutropenia (32%), anaemia (12%), diarrhoea (16%). No events of febrile neutropenia were reported. At data cut-off on 31 Aug 2017, 4 pts are on study. Median progression-free and overall survival was 22 and 35 wks respectively. Response rate (RR) was 5/25 (20%, overall); 5/20 (25%, evaluable pts) including 1 complete response and 1 unconfirmed partial response. Disease control rate for ≥ 12wks was 16/25 (64%) with 3 pts > 52wks. CA19-9 decrease of ≥ 20% was seen in 9/25 pts. Conclusions: OXIRI is an active regimen with RR of 20% despite 84% of pts having prior chemo, with disease control for ≥ 12wks in 64% of pts. Predominant toxicity was neutropenia. This study was supported by the National Medical Research Council Singapore. Clinical trial information: NCT02368860.

BCLC subclassification and tumour characteristics to provide prognostication of outcomes in an Asian population of locally advanced hepatocellular carcinoma treated using selective internal radiation therapy with Yttrium-90

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Background: Selective internal radiation therapy (SIRT) with Yttrium-90 (Y90) is preferentially used in locally advanced hepatocellular carcinoma (HCC) patients in the Barcelona clinic liver cancer (BCLC) B or C cohort. However, the BCLC B cohort has a wide heterogeneity. To address this, Bolondi et al. proposed a BCLC B subclassification system. Additionally, the BCLC C cohort is also diverse in their Child-Pugh (CP) stage and extent of portal vein thrombosis (PVT). The effect of these subclassifications on survival outcomes has not been studied in HCC patients treated using SIRT. Methods: 392 HCC patients treated using SIRT from 1st January 2008 to 17th March 2017 were analyzed. These patients were classified according to the proposed subclassification system for the BCLC B cohort, and CP stage for the BCLC C cohort, and their survival outcomes reviewed. Results: 293 patients met the study’s inclusion criteria. For B1/B2/B3/B4/ C CP-A and C CP-B, the median OS was 48.3/28.7/14.4/13.7/12.8 and 6.6 months respectively. Overall comparison between the subgroups for median OS reached statistical significance (p < 0.001). The Cox proportional-hazards regression analysis found that tumour location defined as unilobar or bilobar disease significantly influenced median OS. In the BCLC C cohort, the extent of portal vein invasion significantly influenced median OS (p < 0.001). For the BCLC C CP-A group, median OS for segmental/sectoral branch invasion, right and/or left portal vein invasion and main portal vein trunk invasion was 24.1, 12.8 and 6.5 months respectively. Conclusions: Bolondi et al.’s subclassification system optimizes prognostic prediction by reducing the clinical heterogeneity in BCLC B HCC patients treated using SIRT. However tumour location, unaccounted for in the proposed subclassification, is also an important prognosticator. For the BCLC C cohort CP stage, extent of PVT, and tumour location were important predictors of treatment outcomes.

Gastric peritoneal carcinomatosis - a retrospective review

AIM

To characterize patients with gastric peritoneal carcinomatosis (PC) and their typical clinical and treatment course with palliative systemic chemotherapy as the current standard of care.

METHODS

We performed a retrospective electronic chart review of all patients with gastric adenocarcinoma with PC diagnosed at initial metastatic presentation between January 2010 and December 2014 in a single tertiary referral centre.

RESULTS

We studied a total of 271 patients with a median age of 63.8 years and median follow-up duration of 5.1 mo. The majority (n = 217, 80.1%) had the peritoneum as the only site of metastasis at initial presentation. Palliative systemic chemotherapy was eventually planned for 175 (64.6%) of our patients at initial presentation, of which 171 were initiated on it. Choice of first-line regime was in accordance with the National Comprehensive Cancer Network Guidelines for Gastric Cancer Treatment. These patients underwent a median of one line of chemotherapy, completing a median of six cycles in total. Chemotherapy disruption due to unplanned hospitalizations occurred in 114 (66.7%), while cessation of chemotherapy occurred in 157 (91.8%), with 42 cessations primarily attributable to PC-related complications. Patients who had initiation of systemic chemotherapy had a significantly better median overall survival than those who did not (10.9 mo vs 1.6 mo, P < 0.001). Of patients who had initiation of systemic chemotherapy, those who experienced any disruptions to chemotherapy due to unplanned hospitalizations had a significantly worse median overall survival compared to those who did not (8.7 mo vs 14.6 mo, P < 0.001).

CONCLUSION

Gastric PC carries a grim prognosis with a clinical course fraught with disease-related complications which may attenuate any survival benefit which palliative systemic chemotherapy may have to offer. As such, investigational use of regional therapies is warranted and required validation in patients with isolated PC to maximize their survival outcomes in the long run.

Microarray-based tumor molecular profiling to direct choice of cisplatin plus S-1 or oxaliplatin plus S-1 for advanced gastric cancer: A multicentre, prospective, proof-of-concept phase 2 trial

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Background: Theoxaliplatin/S-1 (SOX) and cisplatin/S-1 (SP) regimens are interchangeably used in the management of advanced gastric cancer (AGC). We previously developed a classification tool using gene expression signatures which successfully stratified gastric cancer cell lines and primary tumour samples according to their sensitivity to SOX or SP ( Tan et al, Gastroenterology 2011). We now report the first prospective study to evaluate the feasibility and efficacy of using a genomic classifier to tailor treatment in this setting. Methods: Pts with histologically-confirmed locally-advanced, metastatic and recurrent GC were recruited from 3 centres in Singapore and South Korea. Tumours were analysed using the Affymetrix HG-U133 Plus 2.0 array and results were used to classify pts as G1 (oxaliplatin-sensitive), G2 (cisplatin-sensitive) and G3 (status unclear or gene expression not available). G1 and G2 pts were matched to SOX and SP regimens respectively, while G3 pts were assigned SOX. The primary endpoint was best overall response; secondary endpoints were turnaround time and biomarker analyses. Results: Between July 2, 2010, and Apr 2, 2015, we screened 85 AGC pts. 74 pts received at least 1 cycle of treatment and were evaluable for analysis. Median turnaround time was 7 working days (IQR, 5–9). The misclassification rate was 6%. After an initial 30 pts in the G1 subgroup were treated with SOX, subsequent pts ( N = 13) classified as G1 received the SP regimen. The ORR were 44.8%, 8.3%, 26.7% and 55.6% for G1 SOX, G1 SP, G2 SP ( N = 19), G3 SOX ( N = 12) respectively; and was higher in G1 pts treated with SOX compared with SP ( P = 0.033). Post hoc genomic reclassification based on Lei et al (Gastroenterology 2013) confirmed the utility of the metabolic subtype as a predictive marker of benefit from chemotherapy (log rank P value for PFS = 0.004). Conclusions: This bench-to-bedside effort establishes that molecular profiling to direct choice of conventional chemotherapy for AGC is possible within a reasonable timeframe. The clinical utility of our genomic classifiers in question are promising but warrant further investigation. Clinical trial information: NCT01100801.