Quantitative proteomic analysis of HER2 expression in the selection of gastric cancer patients for trastuzumab treatment

BackgroundA wide range of response rates have been reported in HER2-positive gastric cancer (GC) patients treated with trastuzumab. Other HER2-targeted therapies for GC have yet to show efficacy in clinical trials. These findings raise question about the ability of standard HER2 diagnostics to accurately distinguish between GC patients who would and would not benefit from anti-HER2 therapies.Patients and methodsGC patients (n = 237), including a subset from the Trastuzumab in GC (ToGA) trial were divided into three groups based on HER2 status and history of treatment with standard chemotherapy or chemotherapy plus trastuzumab. We applied mass spectrometry-based proteomic analysis to quantify HER2 protein expression in formalin-fixed tumor samples. Using HER2 expression as a continuous variable, we defined a predictive protein level cutoff to identify which patients would benefit from trastuzumab. We compared quantitated protein level with clinical outcome and HER2 status as determined by conventional HER2 diagnostics.ResultsQuantitative proteomics detected a 115-fold range of HER2 protein expression among patients diagnosed as HER2 positive by standard methods. A protein level of 1825 amol/µg was predicted to determine benefit from the addition of trastuzumab to chemotherapy. Trastuzumab treated patients with HER2 protein levels above this cutoff had twice the median overall survival (OS) of their counterparts below the cutoff (35.0 versus 17.5 months, P = 0.011). Conversely, trastuzumab-treated patients with HER2 levels below the cutoff had outcomes similar to HER2-positive patients treated with chemotherapy. (Progression-free survival = 7.0 versus 6.5 months: P = 0.504; OS = 17.5 versus 12.6 months: P = 0.520). HER2 levels were not prognostic for response to chemotherapy.ConclusionsProteomic analysis of HER2 expression demonstrated a quantitative cutoff that improves selection of GC patients for trastuzumab as compared with current diagnostic methods.     

The impact of primary tumour origins in patients with advanced oesophageal,oesophago–gastric junction and gastric adenocarcinoma—individual patient data from 1775 patients in four randomised controlled trials

BackgroundIt is unclear if differential chemotherapy effects exist on overall survival (OS), response rate (RR) and toxicity depending on primary tumour origin [oesophageal versus oesophago–gastric junction (OGJ) versus gastric adenocarcinoma].Patients and methodsA total of 2110 patients were enrolled in four randomised controlled trials (RCTs) assessing fluoropyrimidine ± platinum-based chemotherapy. This analysis used individual patient data and restricted to patients with adenocarcinoma who received one or more dose of chemotherapy. Gastric origin was the control in comparisons of tumour origin.ResultsOf the 2110 patients randomised, 1775 (84%) patients had adenocarcinoma with oesophageal (n = 485), OGJ (n = 457) and gastric (n = 833) origins. The median OS was 9.5 months in oesophageal, 9.3 months in OGJ and 8.7 months in gastric cancer (P = 0.68). RR was 44.1% in oesophageal, 41.1% in OGJ and 35.6% in gastric cancers (P = 0.11 and 0.27, respectively, compared with gastric cancer on multivariate analysis). Toxicity composite end point occurred in 46%, 47% and 45% in oesophageal, OGJ and gastric cancers, respectively (P = 0.85 and 0.62 compared with gastric).ConclusionsIn our large multicentre RCT dataset, no significant differences were demonstrated on multivariate analyses in OS, RR and toxic effects among patients with advanced oesophageal, OGJ and gastric adenocarcinoma. Future RCTs should not exclude oesophageal adenocarcinoma.     

Trastuzumab versus observation for HER2 nonamplified early breast cancer with circulating tumor cells (EORTC 90091-10093, BIG 1-12, Treat CTC): a randomized phase II trial

BackgroundTrastuzumab improves the outcome of women with HER2 positive breast cancer. We aimed to assess whether trastuzumab decreases the detection rate of circulating tumor cells (CTCs) in women with high risk, HER2 nonamplified, early breast cancer.Patients and methodsThe EORTC 90091-10093 BIG 1–12 Treat CTC is a phase II trial, conducted in 70 hospitals and 6 CTC laboratories across 5 European countries. Patients with centrally confirmed HER2 nonamplified breast cancer and ≥1 centrally confirmed CTC per 15 ml of blood by CellSearch® following surgery and (neo)adjuvant chemotherapy were randomized (1 : 1) to 6 cycles of trastuzumab intravenously versus 18 weeks of observation. Randomization was stratified for center, locally confirmed estrogen receptor status and adjuvant versus neoadjuvant chemotherapy. The primary end point was rate of detection of ≥1 CTC per 15 ml of blood at week 18. Secondary end points were invasive disease-free survival (iDFS) and cardiac safety.ResultsBetween 30 April 2013 and 17 October 2016, 1317 patients were screened; 95 (7.2%) had detectable CTC(s), and 63 (4.8%) were randomized to trastuzumab (n = 31) or observation (n = 32). Fifty-eight patients were assessable for the primary end point, 29 in each arm. In 9 of the 58 patients, CTC(s) were still detected at week 18 : 5 in the trastuzumab and 4 in the observation arm (one-sided Fisher’s exact test, P = 0.765). An Independent Data Monitoring Committee recommended stopping further accrual for futility for the primary end point. Median follow-up at database lock was 13 months (IQR 4–16.5). The 1-year iDFS was 93.8% (95% CI 77.3–98.4) in the observation versus 84.8% (95% CI 63.4–94.2) in the trastuzumab arm. No grade 2–4 cardiac events were observed in the trastuzumab arm.ConclusionTrastuzumab does not decrease the detection rate of CTCs in HER2 nonamplified, nonmetastatic breast cancer.     

Human epidermal growth factor receptor 2 (HER2) in gastric cancer: a new therapeutic target

Surgery is the only curative therapy for gastric cancer. In the metastatic setting the objective of treatment is to manage symptoms, improve quality of life and prolong survival, but current treatment options have limited efficacy and some of them exhibit unfavourable toxicity profiles. Fluoropyrimidine, taxanes and platinum-based regimens are used most frequently and offer a response rate of 30-50% with a median overall survival of =1 year. These discouraging data support the need for new therapeutic strategies based on targeted drugs. Trastuzumab, a monoclonal antibody against HER2, has shown survival benefits when given with chemotherapy in all setting of HER2-positive breast cancer patients. The ToGA trial, the first study evaluating the efficacy and safety of adding trastuzumab to chemotherapy in HER-2 positive advanced gastric cancer, showed a significant superiority of combination over chemotherapy alone. Based on these results trastuzumab combined with a cisplatin and fluoropyrimidine regimen appear the new reference treatment for HER-2 positive metastatic gastric cancer.     

Les anticorps conjugués en oncologie : du concept au trastuzumab emtansine (T-DM1)

Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate (ADC) which associates the selective intracellular targeting of the cytotoxic agent, DM1 (maytansine derivative) to the antitumor activity of trastuzumab. T-DM1 targets the epidermal growth factor receptor 2 (HER2), highly expressed in the most aggressive forms of breast cancer. Current standard of care in HER2-positive advanced or metastatic breast cancers has its limitations, particularly after progression on HER2-targeted approved therapies. T-DM1 showed a significant antitumor activity in vitro and in vivo, and in experimental models resistant to HER2-targeted agents. Phase I and II studies showed that the maximum tolerated dose for T-DM1 is 3.6 mg/kg given intravenously every three weeks. At this recommended dose, T-DM1 provided objective tumor responses and favourable safety profile. A phase II randomised study, evaluating T-DM1 in first line vs trastuzumab plus docetaxel, the current standard of care in advanced or metastatic breast cancers, showed improved tolerability and efficacy. Recently, the results of EMILIA, a phase III randomised study assessing, after prior treatment with trastuzumab and a taxane, the efficacy and the safety of T-DM1 vs lapatinib plus capecitabine, confirmed the therapeutic benefit. T-DM1 appears to be an effective therapeutic option to treat patients with HER2-positive metastatic breast cancer.     

Very high quantitative tumor HER2 content and outcome in early breast cancer

BackgroundIt is unknown how a very high tumor total HER2 (human epidermal growth factor receptor-2) content (H2T) influences outcome in early breast cancer treated with adjuvant trastuzumab plus chemotherapy.Patients and methodsH2T was measured using a novel quantitative assay (HERmark®) from formalin-fixed tumor tissue of 899 women who participated in the FinHer trial (ISRCTN76560285). In a chromogenic in situ hybridization (CISH) test, 197 (21.9%) patients had HER2-positive cancer and were randomly assigned to receive trastuzumab or control.ResultsCancer H2T levels varied 1808-fold. High H2T levels were correlated with a positive HER2 status by CISH (P < 0.0001). A nonlinear association was present between H2T and the hazard of distant recurrence in a subpopulation treatment effect pattern plot analysis in CISH-positive disease. Patients with very high H2T (defined by ≥22-fold the median of HER2-negative cancers; 13% of CISH-positive cancers) did not benefit from adjuvant trastuzumab [hazard ratio (HR) 1.23; 95% confidence interval (CI) 0.33–4.62; P = 0.75], whereas the rest of the patients with HER2-positive disease by CISH (87%) did benefit (HR 0.52; 95% CI 0.28–1.00; P = 0.050).ConclusionPatients with HER2-positive breast cancer with very high tumor HER2 content may benefit less from adjuvant trastuzumab compared with those whose cancer has more moderate HER2 content.     

Tumor-infiltrating lymphocytes in patients with HER2-positive breast cancer treated with neoadjuvant chemotherapy plus trastuzumab,lapatinib or their combination: A meta-analysis of randomized controlled trials

BackgroundA relationship between baseline tumor-infiltrating lymphocytes (TIL) and outcomes has been described in HER2-positive breast cancer. Nevertheless, the magnitude of this association and whether this effect differs based on the type of anti-HER2 agent remain controversial. This meta-analysis investigated the association between baseline TIL and pathologic complete response (pCR) rates in HER2-positive breast cancer patients treated with neoadjuvant chemotherapy plus trastuzumab and lapatinib either alone or in combination.MethodsA literature search covering PubMed, Embase and the Cochrane library up to October 31, 2016 identified randomized, controlled trials investigating neoadjuvant chemotherapy plus trastuzumab and lapatinib either alone or in combination where published data for pCR based on pre-treatment TIL scores were available. Two subgroups were considered: high baseline TIL vs. non-high TIL, according to each study definition. Summary risk estimates (odds ratio) and 95% confidence intervals (CI) were calculated for pCR using pre-treatment TIL levels for each trial. Pooled analyses were conducted using random and fixed effects models. Interaction P-values were computed using a Monte Carlo permutation test.ResultsA total of 5 studies (N = 1256 patients) were included. Overall, high TIL subgroup was associated with a significantly increased pCR rate (OR 2.46; 95% CI 1.36–4.43; P = 0.003). No interaction was observed between TIL subgroup (high vs. non-high TIL) and response to anti-HER2 agent(s) (trastuzumab vs. lapatinib vs. their combination; P = 0.747) and chemotherapy (anthracycline and taxanes vs. taxanes only; P = 0.201). A stronger association between high TIL subgroup and pCR rates was observed when examining only the 4 studies using anthracycline- and taxane- based neoadjuvant chemotherapy and the 60% cut-off for high TIL (N = 869, NeoALTTO excluded) with an OR of 2.88 (95% CI 2.03–4.08; P < 0.001).ConclusionsIn HER2-positive breast cancer, high baseline TIL are associated with increased pCR probability irrespective of neoadjuvant anti-HER2 agent(s) and chemotherapy regimens used.     

Multicenter phase II study of trastuzumab in combination with capecitabine and oxaliplatin for advanced gastric cancer

BackgroundTrastuzumab has been approved for use in combination with fluoropyrimidine plus cisplatin for the treatment of human epidermal growth factor receptor 2 (HER2)-positive advanced gastric cancer (AGC). Although capecitabine plus oxaliplatin (XELOX) is a standard first-line regimen for AGC, combination trastuzumab plus XELOX has not been studied.MethodsPatients with metastatic or unresectable HER2-positive AGC were diagnosed by either HER2 immunohistochemistry (IHC) 3+ or IHC 2+/fluorescence in-situ hybridisation (FISH)+ received intravenous trastuzumab (8 mg/kg for first cycle and 6 mg/kg for subsequent cycles on day 1) plus oral capecitabine (1000 mg/m² twice daily on days 1–14) and intravenous oxaliplatin (130 mg/m² on day 1), every 3 weeks. The primary end-point was the objective response rate, and secondary end-points included progression-free survival (PFS), overall survival (OS) and toxicity profiles.ResultsFifty-five HER2-positive AGC patients were enrolled between August 2011 and February 2013. The median age was 57 years (range = 29–74). The confirmed objective response rate was 67% (95% confidence interval (CI) = 54–80%). After a median follow-up period of 13.8 months (range = 6.1–23.9), the median PFS and OS were 9.8 months (95% CI = 7.0–12.6) and 21.0 months (95% CI = 6.4–35.7), respectively. Frequently encountered grade 3–4 toxicities included neutropenia (18%), anaemia (11%), and peripheral neuropathy (11%). There was a treatment-related death caused by severe diarrhoea and complicated sepsis.ConclusionCombination of trastuzumab and XELOX is well tolerated and highly effective in patients with HER2-positive AGC.     

HER2 and gastric cancer: a novel therapeutic target for trastuzumab

HER2 protein overexpression by immunohistochemistry (IHC) and/or erB2 gene amplification by in situ hybridization (ISH) was detected in 4-28% of gastric or gastro-oesophageal junction (GOJ) cancers. Most studies have shown that HER2-overexpressing gastric cancers were worse prognosis. Trastuzumab is a humanized monoclonal antibody directed against HER2 with known efficacy in patients with HER2+ early or metastatic breast cancer. The international randomized trial ToGA study showed the superiority of the combination of trastuzumab with chemotherapy doublet fluoropyrimidine (5-FU or capecitabine) plus cisplatin (FP) every three weeks compared with chemotherapy alone in terms of overall survival : 13.8 versus 11.1 months (HR: 0.74, 95% CI: 0.60-0.91, P = 0.0046) in HER2+ advanced gastric cancers. The benefit was even greater in the subgroup with HER2 overexpression (16% of the screened population) as defined by IHC3+ or IHC2+ confirmed by positive ISH test. Trastuzumab plus FP chemotherapy has become the standard treatment for patients with HER2+ non-pretreated metastatic adenocarcinoma of the stomach or GOJ cancer. All these cancers should be tested for HER2 on paraffin block resection or biopsy specimens of the primary tumour or metastases. Endoscopic gastric biopsies should be multiple. The IHC should be the initial test. The standardized immunohistochemical scoring system differs from that recommended for breast cancer given the heterogeneity of HER2 expression and the frequency of incomplete membranous staining in gastric cancers. Equivocal IHC2+ tumours should be tested by ISH with two tools: fluorescence in situ hybridization (FISH) or bright field in situ hybridization (SISH). The perspectives are the assessment of trastuzumab in the perioperative and adjuvant setting, the development of novel anti-HER2 drugs and research into mechanisms of resistance and predictive molecular markers.     

Preliminary safety and efficacy of first-line pertuzumab combined with trastuzumab and taxane therapy for HER2-positive locally recurrent or metastatic breast cancer (PERUSE)

BackgroundPertuzumab combined with trastuzumab and docetaxel is the standard first-line therapy for HER2-positive metastatic breast cancer, based on results from the phase III CLEOPATRA trial. PERUSE was designed to assess the safety and efficacy of investigator-selected taxane with pertuzumab and trastuzumab in this setting.Patients and methodsIn the ongoing multicentre single-arm phase IIIb PERUSE study, patients with inoperable HER2-positive advanced breast cancer (locally recurrent/metastatic) (LR/MBC) and no prior systemic therapy for LR/MBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab [8 mg/kg loading dose, then 6 mg/kg every 3 weeks (q3w)] and pertuzumab (840 mg loading dose, then 420 mg q3w) until disease progression or unacceptable toxicity. The primary end point was safety. Secondary end points included overall response rate (ORR) and progression-free survival (PFS).ResultsOverall, 1436 patients received at least one treatment dose (initially docetaxel in 775 patients, paclitaxel in 589, nab-paclitaxel in 65; 7 discontinued before starting taxane). Median age was 54 years; 29% had received prior trastuzumab. Median treatment duration was 16 months for pertuzumab and trastuzumab and 4 months for taxane. Compared with docetaxel-containing therapy, paclitaxel-containing therapy was associated with more neuropathy (all-grade peripheral neuropathy 31% versus 16%) but less febrile neutropenia (1% versus 11%) and mucositis (14% versus 25%). At this preliminary analysis (52 months’ median follow-up), median PFS was 20.6 [95% confidence interval (CI) 18.9–22.7] months overall (19.6, 23.0 and 18.1 months with docetaxel, paclitaxel and nab-paclitaxel, respectively). ORR was 80% (95% CI 78%–82%) overall (docetaxel 79%, paclitaxel 83%, nab-paclitaxel 77%).ConclusionsPreliminary findings from PERUSE suggest that the safety and efficacy of first-line pertuzumab, trastuzumab and taxane for HER2-positive LR/MBC are consistent with results from CLEOPATRA. Paclitaxel appears to be a valid alternative taxane backbone to docetaxel, offering similar PFS and ORR with a predictable safety profile.ClinicalTrials.govNCT01572038.     

A case report of trastuzumab dose in gastric cancer

Introduction

Trastuzumab (Herceptin®, F. Hoffman-La Roche) is now approved for the treatment of metastatic HER2-positive gastric cancer based on the improved survival observed on the phase III Trastuzumab for Gastric Adenocarcinoma (ToGA) study. Standard dosing of trastuzumab is currently extrapolated from breast cancer data: a 3-week schedule (8 mg/kg load, 6 mg/kg q 3 weeks) or a weekly schedule (4 mg/kg load, 2 mg/kg q week).

Case study

Our case study examines an HER2-positive metastatic gastric cancer patient that required a higher than currently recommended standard dose of trastuzumab to achieve treatment response.

Discussion

Several mechanisms may explain these findings and include higher clearance of trastuzumab, higher tumor burden, and pharmacologic resistance in metastatic gastric cancer versus breast cancer. The question of trastuzumab dosing in gastric cancer is currently being evaluated in a phase III clinical trial.Key Words: Trastuzumab, metastatic gastric cancer, pharmacokinetics     

Effect of docetaxel duration on clinical outcomes: exploratory analysis of CLEOPATRA,a phase III randomized controlled trial

BackgroundCombination pertuzumab, trastuzumab, and docetaxel (D) is considered standard first-line treatment of human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer. This post hoc, exploratory analysis of CLEOPATRA study data evaluated the clinical effects of D treatment duration within this regimen. The clinical benefits of pertuzumab and trastuzumab by different durations of D treatment were also evaluated.Patients and methodsPatients with HER2-positive metastatic breast cancer received trastuzumab and D plus pertuzumab or placebo. Clinical outcomes were analyzed by the number of D cycles that patients received (<6D, 6D, or >6D). Progression-free survival (PFS) and overall survival (OS) for each treatment arm within each D cycle group were estimated using the Kaplan–Meier approach. Time-dependent, multivariate Cox regression was applied to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for HER2-targeted therapy and D cycle groups.ResultsOverall, 804 patients received <6D (n = 119), 6D (n = 210), or >6D (n = 475) cycles. After adjusting for pertuzumab benefits versus placebo (PFS HR = 0.61, 95% CI 0.51–0.74, P < 0.0001; OS HR = 0.60, 95% CI, 0.49–0.74, P < 0.0001), >6D versus 6D cycles was not associated with statistically significant improvements in PFS (HR = 0.80, 95% CI 0.63–1.01, P = 0.0640) or OS (HR = 0.88, 95% CI 0.69–1.12, P = 0.3073). Consistent improvements in PFS and OS were observed with pertuzumab versus placebo, irrespective of D duration. The HRs for PFS were 0.395, 0.615, and 0.633 for <6D, 6D, and >6D cycles, respectively (P < 0.05 for all D cycle groups). Corresponding HRs for OS were 0.577, 0.700, and 0.612, respectively (P < 0.05 for <6D and >6D).ConclusionsAfter accounting for pertuzumab benefits, more than six cycles of D treatment was not associated with significant improvements in either PFS or OS compared with six cycles. The addition of pertuzumab to trastuzumab improved clinical outcomes versus trastuzumab plus placebo, regardless of D treatment duration.ClinicalTrials.gov identifierNCT00567190.     

A phase two randomised trial of neratinib monotherapy versus lapatinib plus capecitabine combination therapy in patients with HER2+ advanced breast cancer

BackgroundThe safety and efficacy of neratinib monotherapy were compared with that of lapatinib plus capecitabine in patients with human epidermal growth factor receptor-2-positive (HER2+), locally advanced/metastatic breast cancer and prior trastuzumab treatment.MethodsPatients received neratinib 240 mg/d continuously (n = 117) or lapatinib 1250 mg/d continuously plus capecitabine 2000 mg/m² per day on days 1–14 of each 21-d cycle (n = 116). The primary aim was to demonstrate non-inferiority of neratinib for progression-free survival (PFS).FindingsThe non-inferiority of neratinib was not demonstrated when compared with lapatinib plus capecitabine (hazard ratio, 1.19; 95% confidence interval, 0.89–1.60; non-inferiority margin, 1.15). Median PFS for neratinib was 4.5 months versus 6.8 months for lapatinib plus capecitabine and median overall survival was 19.7 months versus 23.6 months. Objective response rate (neratinib, 29% versus lapatinib plus capecitabine, 41%; P = 0.067) and clinical benefit rate (44% versus 64%; P = 0.003) were lower for the neratinib arm but consistent with previously reported results. In both treatment arms, diarrhoea was the most frequently reported treatment-related adverse event of any grade (neratinib, 85% versus lapatinib plus capecitabine, 68%; P = 0.002) and of grade 3/4 (28% versus 10%; P < 0.001), but was typically managed with concomitant anti-diarrhoeal medication and/or study treatment modification. Importantly, neratinib had no significant skin toxicity.InterpretationThe results are considered as inconclusive since neither inferiority nor non-inferiority of treatment with neratinib versus lapatinib plus capecitabine could be demonstrated. The study confirmed relevant single-agent clinical activity and acceptable overall tolerability of neratinib in patients with recurrent HER2+ advanced breast cancer.     

Escalating and de-escalating treatment in HER2-positive early breast cancer

The current standard adjuvant systemic treatment of early HER2-positive breast cancer consists of chemotherapy plus 12 months of trastuzumab, with or without endocrine therapy. Several trials have investigated modifications of the standard treatment that are shorter and less resource-demanding (de-escalation) or regimens that aim at dual HER2 inhibition or include longer than 12 months of HER2-targeted treatment (escalation). Seven randomized trials investigate shorter than 12 months of trastuzumab treatment duration. The shorter durations were not statistically inferior to the 1-year duration in the 3 trials with survival results available, but 2 of the trials were small and 1 had a relatively short follow-up time of the patients at the time of reporting. The pathological complete response (pCR) rates were numerically higher in all 9 randomized trials that compared chemotherapy plus dual HER2 inhibition consisting of trastuzumab plus either lapatinib, neratinib, or pertuzumab with chemotherapy plus trastuzumab as neoadjuvant treatments, but the superiority of chemotherapy plus dual HER2-inhibition over chemotherapy plus trastuzumab remains to be demonstrated in the adjuvant setting. One year of adjuvant trastuzumab was as effective as 2 years of trastuzumab in the HERA trial, and was associated with fewer side-effects. Extending 1-year adjuvant trastuzumab treatment with 1 year of neratinib improved disease-free survival in the ExteNET trial, but the patient follow-up times are still short, and no overall survival benefit was reported. Several important trials are expected to report results in the near future and may modify the current standard.     

Multicentre randomised phase II trial of gemcitabine + platinum,with or without trastuzumab,in advanced or metastatic urothelial carcinoma overexpressing Her2

AimTo investigate the efficacy and safety of gemcitabine and platinum salt, with or without trastuzumab, in patients with locally advanced or metastatic urothelial carcinoma overexpressing Her2.MethodsThe main eligibility criterion was Her2 overexpression on immunohistochemistry (IHC 2+ or 3+) of primary tumour tissue confirmed by fluorescence in situ hybridisation (FISH). Patients were randomised to Arm A: gemcitabine 1000 mg/m² (days 1 and 8) plus either cisplatin (70 mg/m²) or carboplatin (AUC = 5) (day 1 every 3 weeks) or Arm B: added trastuzumab (8 mg/kg loading dose, then 6 mg/kg every 21 days until progression). The primary end-point was progression-free survival (PFS).ResultsAmong 563 screened patients, 75 (13.3%) were Her2 positive (IHC 2+/3+ and FISH+) and 61 met all eligibility criteria (median age, 64 years; 54/61 males; 50/61 baseline ECOG-PS 0-1; 11 locally advanced and 50 metastatic). There was no significant difference between Arms A and B in median PFS (10.2 versus 8.2 months, respectively, p = 0.689), objective response rate (65.5% versus 53.2%, p = 0.39), and median overall survival (15.7 versus 14.1 months, respectively, p = 0.684). In an exploratory analysis, trastuzumab-treated patients receiving cisplatin rather than carboplatin-based chemotherapy fared better (PFS: 10.6 versus 8.0; OS: 33.1 versus 9.5 months). Myelosuppression was the main grade 3/4 toxicity. A case of grade 3 cardiotoxicity and one death from febrile neutropenia occurred in arm B.ConclusionThe unexpectedly low incidence of Her2 overexpression precluded the detection of a significant difference in efficacy on addition of trastuzumab to platinum-based chemotherapy with gemcitabine. However, the satisfactory tolerance of the combination warrants further studies, especially of the cisplatin-based combination, in well-defined patient subsets.     

Class III β-tubulin,but not ERCC1, is a strong predictive and prognostic marker in locally advanced head and neck squamous cell carcinoma

BackgroundRecent researches revealed that class III β-tubulin (TUBB3) is a prognostic marker in various tumors and role of TUBB3 in head and neck squamous cell carcinoma (HNSCC) is not defined yet. We analyzed the significance of TUBB3 expression along with p53 and ERCC1 in locally advanced HNSCC patients receiving cisplatin-based induction chemotherapy.Materials and methodsRetrospective review of medical records at Seoul National University Hospital between 1998 and 2007 was carried out. Immunohistochemical stain of TUBB3, p53, and ERCC1 was done in paraffin-embedded tumor tissue. We assessed response to treatment, progression-free survival (PFS), overall survival (OS), and cancer-specific survival (CSS).ResultsEighty-five patients with oropharyngeal, hypopharyngeal, and laryngeal cancers received induction chemotherapy with 5-fluorouracil (5-FU) and cisplatin (n = 55), or 5-FU, cisplatin, and docetaxel (Taxotere) (n = 30). Eighty-three received definitive treatment after induction chemotherapy, where 62 received radiotherapy and 21 received surgery. TUBB3-positive patients showed lower response rate than TUBB3-negative patients (69% versus 88%, P = 0.039). Shorter median PFS was observed in TUBB3-positive group (12 versus 47 months, P = 0.001). Shorter median OS was observed in TUBB-positive group not reaching statistical significance (30 versus 59 months, P = 0.072). TUBB3 status significantly influenced CSS (35 months versus not reached, P = 0.017). Positive p53 status was related to poorer OS and CSS. ERCC1 showed no influence on chemotherapy response, PFS, OS, and CSS.ConclusionTUBB3 is a predictive and prognostic marker along with well-known p53 in HNSCC patients receiving cisplatin-based induction chemotherapy. Clinical impact of ERCC1 is not evident in this setting.     

Duration of adjuvant trastuzumab in HER2 positive breast cancer: Overall and disease free survival results from meta-analyses of randomized controlled trials

BackgroundOne year of trastuzumab, chosen empirically, improves survival of women with early-stage, HER2-positive breast cancer but also adds substantially to cost, toxicity, and inconvenience. Longer treatment does not improve outcomes, but potentiates toxicities.MethodsMedline, Embase, and major conference proceedings were searched systematically in June 2017 to identify Randomized Controlled Trials (RCTs) comparing one year versus shorter durations of trastuzumab in adjuvant treatment of breast cancer. Reported Hazard-Ratios (HR) for Overall Survival (OS) and Disease-Free Survival (DFS), and Odds-Ratio for cardiac events, with respective 95% Confidence Intervals (CI) from each study was weighted using generic inverse-variance, and pooled in a meta-analysis. Inter-study heterogeneity and sub-group difference (based on hormone-receptors and node-positivity) were assessed using I², and chi² statistics, respectively.ResultsFour studies (n = 7614) satisfied inclusion criteria. Individual RCTs had diverse pre-specified upper-limits of 95% CI for declaring non-inferiority (range: <1.15 to <1.53). Pooled results demonstrated significant improvements in OS (HR 1.28, p = 0.04), and DFS (HR 1.24, p = 0.005) with 1 year of trastuzumab compared to shorter durations. Absence of multiplicity argument allowed for declaring superiority of 1 year of trastuzumab based on our results despite non-inferiority designs of individual trials. No influence on overall effect by duration of trastuzumab in experimental arm (9 weeks versus 6 months) was noted. No statistical interaction by hormone-receptor status and node-positivity on overall results was noticed [p(sub-group difference) 0.73, and 0.52, respectively]. Odds-Ratio for cardiac events was 2.65 (p < 0.001) favoring shorter duration.ConclusionOne year of trastuzumab prolongs overall, and disease-free survivals in women with early-stage HER2 positive breast cancer compared to shorter durations and this should remain as the standard of care. Cardiotoxicity increased significantly with the 1-year treatment.     

Efficacy of trastuzumab in Japanese patients with HER2-positive advanced gastric or gastroesophageal junction cancer: a subgroup analysis of the Trastuzumab for Gastric Cancer (ToGA) study

Background

The Trastuzumab for Gastric Cancer (ToGA) study is the first international trial to include Japanese patients with human epidermal growth factor 2 (HER2) positive advanced/metastatic gastric or gastroesophageal junction cancer. ToGA showed that trastuzumab plus chemotherapy (capecitabine/cisplatin or 5-fluorouracil/cisplatin) improved overall survival in the overall population (hazard ratio 0.74). Regional differences in outcome in favor of Japanese populations were observed in other studies; therefore, subgroup analyses of ToGA may contribute to the evaluation of the potential benefits of this regimen in Japanese patients.

Methods

We performed subgroup analyses on 101 Japanese patients enrolled into ToGA (trastuzumab plus chemotherapy, n?=?51; chemotherapy, n?=?50).

Results

Median overall survival in the Japanese subgroup was 15.9?months (95% confidence interval 12–25) for trastuzumab plus chemotherapy and 17.7?months (95% confidence interval 12–24) for chemotherapy (hazard ratio 1.00; 95% confidence interval 0.59–1.69). After adjusting for prespecified covariates, the estimated hazard ratio for overall survival was 0.68 (95% confidence interval 0.36–1.27). Further post hoc and exploratory examinations supported the robustness of the adjusted hazard ratios.

Conclusions

After adjusting for imbalanced patient backgrounds between arms, overall survival of Japanese patients with human epidermal growth factor 2 positive advanced/metastatic gastric or gastroesophageal junction cancer who received trastuzumab plus chemotherapy was improved compared with patients who received chemotherapy alone.     

Defining prognosis for women with breast cancer and CNS metastases by HER2 status

BackgroundThe purpose of this retrospective study was to determine, in a cohort of patients with breast cancer and central nervous system (CNS) metastases, the effect of trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive disease and to compare this with that of patients with HER2-negative disease.MethodsFive hundred and ninety-eight patients with invasive breast cancer, CNS metastases and known HER2 status were identified. Time to CNS metastases and survival after CNS metastases were estimated by the Kaplan–Meier method, and Cox models were fitted to determine the association between HER2 status, trastuzumab treatment and outcomes after adjustment for other patient characteristics.ResultsIn the multivariable model, patients with HER2-negative disease [Hazard ratio (HR) 1.50, 95% confidence interval (CI) 1.15–1.95, P = 0.003] and patients with HER2-positive disease who did not receive trastuzumab (HR 2.13, 95% CI 1.51–3.00, P < 0.0001) had shorter times to CNS metastases compared with patients with HER2-positive disease who had received trastuzumab as first-line therapy for metastases. Furthermore, patients with HER2-negative disease (HR 1.66, 95% CI 1.31–2.12, P < 0.0001) and patients with HER2-positive disease who had never received trastuzumab (HR 1.34, 95% CI 0.78–2.30, P = 0.28) had an increased hazard of death compared with patients with HER2-positive disease who had received trastuzumab before or at the time of CNS metastases diagnosis.ConclusionIn our cohort of patients with breast cancer and CNS metastases, patients with HER2-positive disease treated with trastuzumab had longer times to development of and better survival from CNS metastases compared with patients with HER2-positive disease who had never received trastuzumab and patients with HER2-negative breast cancer.     

An exploratory analysis of the factors leading to delays in cancer drug reimbursement in the European Union: The trastuzumab case

BackgroundThe European Union (EU) has adopted a common procedure for granting marketing authorisation for cancer drugs. Nevertheless, pricing and reimbursement decisions are a competency of EU national governments, and their policies are diverse. We aimed to evaluate the time for trastuzumab reimbursement approval and its association to health expenditure, to health policy performance, to the availability of cost-effectiveness studies and to breast cancer outcome.MethodsBreast cancer outcome was estimated by the mortality/incidence (M/I) ratio. Trastuzumab reimbursement approval dates were provided by Roche. Spearman’s rank correlation and Wilcoxon rank-sum test were used to evaluate associations and/or differences between the variables studied. Additional analyses were made by grouping countries according to compliance to the 180 day timeframe stipulated in the EU 89/105/EEC Directive for drug pricing and reimbursement.ResultsA statistically significant inverse and strong correlation between breast cancer M/I ratio and health expenditure (r_s = –0.730, p < 0.001) and health policy performance (r_s = –0.711, p < 0.001) was found, meaning the better the score and the higher the expenditure, the fewer patients died after a breast cancer diagnosis. Factors associated with trastuzumab faster reimbursement and compliance to the 89/105/EEC Directive were better health policy score, higher health expenditure and availability of cost-effectiveness studies.ConclusionHigher health policy scores and health expenditure are associated with faster reimbursement of trastuzumab and better breast cancer outcome. Although the study design does not allow inference of causal associations, a marked difference is observed between Eastern and Western Europe, with long delays and increased breast cancer mortality identified in Eastern European countries.