Epiregulin gene expression as a biomarker of benefit from cetuximab in the treatment of advanced colorectal cancer

Background:

Anti-EGFR antibody, cetuximab, improves overall survival (OS) in K-ras wild-type chemotherapy–refractory colorectal cancer. Epidermal growth factor receptor ligand epiregulin (EREG) gene expression may further predict cetuximab benefit.

Methods:

Tumour samples from a phase III clinical trial of cetuximab plus best supportive care (BSC) vs BSC alone (CO.17) were analysed for EREG mRNA gene expression. Predictive effects of high vs low EREG on OS and progression-free survival (PFS) were examined for treatment–biomarker interaction.

Results:

Both EREG and K-ras status were ascertained in 385 (193 cetuximab, 192 BSC) tumour samples. Within the high EREG and K-ras wild-type status (‘co-biomarker'')-positive group (n=139, 36%), median PFS was 5.4 vs 1.9 months (hazard ratio (HR) 0.31; P<0.0001), and median OS was 9.8 vs 5.1 months (HR 0.43; P<0.001) for cetuximab vs BSC, respectively. In the rest (n=246, 64%), PFS (HR 0.82; P=0.12) and OS (HR 0.90; P=0.45) were not significantly different. Test for treatment interaction showed a larger cetuximab effect on OS (HR 0.52; P=0.007) and PFS (HR 0.49; P=0.001) in the co-biomarker-positive group.

Conclusion:

In pre-treated K-ras wild-type status colorectal cancer, patients with high EREG gene expression appear to benefit more from cetuximab therapy compared with low expression. Epiregulin as a selective biomarker requires further evaluation.     

Randomised phase II trial of S-1 plus oxaliplatin vs S-1 in patients with gemcitabine-refractory pancreatic cancer

Background:

This randomised, open-label, multicenter phase II study compared progression-free survival (PFS) of S-1 plus oxaliplatin (SOX) with that of S-1 alone in patients with gemcitabine-refractory pancreatic cancer.

Methods:

Patients with confirmed progressive disease following the first-line treatment with a gemcitabine-based regimen were randomised to receive either S-1 (80/100/120 mg day⁻¹ based on body surface area (BSA), orally, days 1–28, every 6 weeks) or SOX (S-1 80/100/120 mg day⁻¹ based on BSA, orally, days 1–14, plus oxaliplatin 100 mg m⁻², intravenously, day 1, every 3 weeks). The primary end point was PFS.

Results:

Between January 2009 and July 2010, 271 patients were randomly allocated to either S-1 (n=135) or SOX (n=136). Median PFS for S-1 and SOX were 2.8 and 3.0 months, respectively (hazard ratio (HR)=0.84; 95% confidence interval (CI), 0.65–1.08; stratified log-rank test P=0.18). Median overall survival (OS) was 6.9 vs 7.4 months (HR=1.03; 95% CI, 0.79–1.34; stratified log-rank test P=0.82). The response rate (RR) was 11.5% vs 20.9% (P=0.04). The major grade 3/4 toxicities (S-1 and SOX) were neutropenia (11.4% and 8.1%), thrombocytopenia (4.5% and 10.3%) and anorexia (12.9% and 14.7%).

Conclusions:

Although SOX showed an advantage in RR, it provided no significant improvement in PFS or OS compared with S-1 alone.     

Vascular endothelial growth factor D expression is a potential biomarker of bevacizumab benefit in colorectal cancer

Background:

Bevacizumab prolongs progression-free survival (PFS) in patients with metastatic colorectal cancer. We analysed the protein expression levels of vascular endothelial growth factor (VEGF) ligands and receptors to determine their prognostic and predictive effects.

Methods:

We graded expression of VEGF-A, VEGF-B, VEGF-C, VEGF-D, VEGF-R1, and VEGF-R2 to assess whether overexpression predicted bevacizumab resistance in samples from 268 of 471 patients randomised to capecitabine (C), capecitabine and bevacizumab (CB), or CB and mitomycin (CBM) in the MAX trial and extended the analysis to the CAIRO-2 population.

Results:

Patients with low expression of VEGF-D (0, 1+) benefited from bevacizumab treatment (PFS hazard ratio (HR) (C vs CB+CBM), 0.21; 95% CI, 0.08–0.55; overall survival (OS) HR, 0.35; 95% CI, 0.13–0.90). Patients with higher VEGF-D expression received less benefit (VEGF-D 2+ PFS HR, 0.67; 95% CI, 0.45–1.00; OS HR, 0.82; 95% CI, 0.52–1.30; VEGF-D 3+ PFS HR, 0.77; 95% CI, 0.50–1.17; OS HR, 1.28; 95% CI, 0.79–2.09) (P interaction <0.05). In CAIRO-2, there was no difference in PFS or OS according to VEGF-D expression.

Conclusions:

The predictive value of VEGF-D expression for bevacizumab may depend on the chemotherapy backbone used. Further evaluation is required before clinical utilisation.     

Aspirin as a neoadjuvant agent during preoperative chemoradiation for rectal cancer

Background:

Recently, many studies have suggested a possible adjuvant role of aspirin in colorectal cancer, reporting a positive prognostic effect with its use in patients with established disease. The aim of this study was to investigate the anticancer effect of aspirin use during preoperative chemoradiation for rectal cancer.

Methods:

Two hundred and forty-one patients with stage II–III rectal cancer and candidates for chemoradiation (CRT) were selected and assigned to two groups: group 1, patients taking aspirin at the time of diagnosis, and group 2, all others. Treatment and oncological outcomes were explored.

Results:

Aspirin use was associated with a higher rate of tumour downstaging (67.6% vs 43.6%, P=0.01), good pathological response (46% vs 19% P<0.001), and a slightly, although not significant, higher rate of complete pathological response (22% vs 13% P=0.196). Aspirin use was also associated with a better 5-year progression-free survival (86.6% vs 67.1% hazard rate (HR)=0.20; 95% CI=0.07–0.60) and overall survival (90.6% vs 73.2% HR=0.21; 95% CI=0.05–0.89). Although chance of local relapse was similar (HR=0.6; 95% CI=0.06–4.5), aspirin use was associated with a lower risk of developing metastasis (HR=0.30; 95% CI=0.10–0.86).

Conclusions:

Aspirin might have anticancer activity against rectal cancer during preoperative CRT. This finding could be clinically relevant and should be further investigated with randomised trials.     

A randomised phase II trial of selumetinib vs selumetinib plus temsirolimus for soft-tissue sarcomas

Background:

The MEK inhibitor, selumetinib, suppresses soft-tissue sarcoma (STS) cell proliferation in vitro. Mammalian target of rapamycin inhibitors possess modest activity against STS; however, resistance develops via MAPK pathway feedback activation. The combination of selumetinib and temsirolimus synergistically inhibits STS cell line growth. Therefore, a randomized phase II trial of selumetinib vs selumetinib plus temsirolimus was conducted.

Methods:

Seventy-one adults with advanced STS who received ⩽2 prior chemotherapeutics were randomized to selumetinib 75 mg p.o. bid and allowed to crossover upon progression, or to selumetinib 50 mg p.o. bid plus temsirolimus 20 mg i.v. weekly, with primary endpoint of progression-free survival (PFS).

Results:

There was no difference in PFS between the two arms for the overall cohort (median 1.9 vs 2.1 months); an improved median PFS was observed in the combination arm (N=11) over single agent (N=10) in the prespecified leiomyosarcoma stratum (median 3.7 vs 1.8 months; P=0.01). Four-month PFS rate was 50% (95% confidence interval 0.19–0.81) with the combination vs 0% with selumetinib alone in the leiomyosarcoma cohort. Most common grade 3/4 adverse events with the combination were mucositis (29%), lymphopenia (26%), neutropenia and anaemia (20% each).

Conclusions:

While single-agent selumetinib has no significant activity in STS, the combination may be active for leiomyosarcomas.     

Thymidine synthase,thymidine phosphorylase,and excision repair cross-complementation group 1 expression as predictive markers of capecitabine plus cisplatin chemotherapy as first-line treatment for patients with advanced oesophageal squamous cell carcinoma

Background:

Our purpose was to evaluate thymidine synthase (TS), thymidine phosphorylase (TP), and excision repair cross-complementation group 1 (ERCC1) expression as biomarkers for capecitabine and cisplatin (XP) combination chemotherapy in patients with metastatic oesophageal squamous cell cancer.

Method:

A total of 113 patients with metastatic oesophageal squamous cell cancer were treated with XP chemotherapy at the Samsung Medical Center between 2003 and 2007, of whom 72 had available clinical data and paraffin blocks for immunohistochemistry of TS, TP, and ERCC1.

Results:

The median age of the 72 patients was 62 years. The overall response rate (RR) was 51.4%. The median progression-free survival (PFS) and overall survival (OS) were 4.2 and 12.0 months, respectively. High expression of TS and TP was associated with a higher RR than was low expression of TS and TP (54.1 vs 40.5%, P=0.022). Strong ERCC1 expression and a low TS score were identified as unfavourable independent risk factors for PFS (HR 10.71, 95% confidence interval (CI) 2.1–54.7, P=0.004 for strong ERCC1 expression; and HR 2.9, 95% CI 1.0–7.9, P=0.044 for low TS score). Strong ERCC1 expression was identified as an unfavourable independent risk factor for OS (HR 3.73, 95% CI 1.39–10.0, P=0.009).

Conclusion:

These data indicate that expression of TS, TP, and ERCC1 may be predictive markers for response and survival in patients with metastatic oesophageal squamous cell cancer receiving XP chemotherapy.     

ERCC1 is a prognostic biomarker in locally advanced head and neck cancer: results from a randomised,phase II trial

Background:

Cisplatin-radiotherapy is a preferred standard for locally advanced, head and neck squamous cell carcinoma (HNSCC). However, the cisplatin-attributable survival benefit is small and toxicity substantial. A biomarker of cisplatin resistance could guide treatment selection and spare morbidity. The ERCC1-XPF nuclease is critical to DNA repair pathways resolving cisplatin-induced lesions.

Methods:

In a phase II trial, patients with untreated Stage III-IVb HNSCC were randomised to cisplatin-radiotherapy with/without erlotinib. Archived primary tumours were available from 90 of 204 patients for this planned substudy. Semi-quantitative ERCC1 protein expression (H-score) was determined using the FL297, 4F9, and 8F1 antibodies. The primary analysis evaluated the relationship between continuous ERCC1 protein expression and progression-free survival (PFS). Secondary analyses included two pre-specified ERCC1 cutpoints and performance in HPV-associated disease.

Results:

Higher ERCC1 expression was associated with inferior PFS, as measured by the specific antibodies FL297 (HR=2.5, 95% CI=1.1–5.9, P=0.03) and 4F9 (HR=3.0, 95% CI=1.2–7.8, P=0.02). Patients with increased vs decreased/normal ERCC1 expression experienced inferior PFS (HR=4.8 for FL297, P=0.003; HR=5.5 for 4F9, P=0.007). This threshold remained prognostic in HPV-associated disease.

Conclusion:

ERCC1-XPF protein expression by the specific FL297 and 4F9 antibodies is prognostic in patients undergoing definitive cisplatin-radiotherapy for HNSCC, irrespective of HPV status.     

Phase I trial outcomes in older patients with advanced solid tumours

Background:

This study had two aims: (a) to test the hypothesis that advanced age is associated with lower levels of tolerability and clinical benefit to experimental Phase I trial agents; (b) to assess the validity of the Royal Marsden Hospital (RMH) prognostic score as a patient selection tool in older patients.

Methods:

Clinico-pathological characteristics and treatment outcomes of all patients treated consecutively from 2005 to 2009 in phase I trials at the RMH were recorded. All toxicity and clinical outcome data were compared between patients aged below and above 65 years of age.

Results:

One thousand and four patients were treated in 30 Phase I trials, with 315 (31%) patients aged 65 years and older. Grade 3–5 toxicities (22.8% vs 24.8% (P=0.52)), trial discontinuation (6% vs 4% P=0.33), and dose interruptions (8.0% vs 8.0% (P=0.96)) were observed at similar rates in patients below and above 65 years of age, respectively. The overall response rate 5.2% vs 4.1%, progression-free survival (PFS) 1.9 vs 3.5 months and clinical benefit rate (CBR) at 6 months 15.2% vs 14.3% were comparable in both groups. To avoid bias due to the potential therapeutic benefit of abiraterone, comparisons were repeated excluding prostate cancer patients with similar results (ORR 4.6% vs 4%, PFS 1.8 vs 3.0 months, CBR at 6 months 13.5% vs 9.5%). Multivariate analysis indicated that the previously identified RMH score (including albumin and lactate dehydrogenase levels) was an accurate predictor of outcome.

Conclusions:

Phase I clinical trials should be considered in patients with advanced cancers regardless of age, as older patients who enter these have similar safety and efficacy outcomes as their younger counterparts. The RMH prognostic score can assist in the selection of suitable older patients.     

RAD21 cohesin overexpression is a prognostic and predictive marker exacerbating poor prognosis in KRAS mutant colorectal carcinomas

Background:

RAD21 is a component of the cohesion complex and is integral to chromosome segregation and error-free DNA repair. RAD21 is functionally important in tumour progression but its role in colorectal carcinoma (CRC) is unclear. We therefore assessed its clinicopathological and prognostic significance in CRC, as well as its effect on chemosensitivity.

Methods:

A retrospective observation study examined RAD21 expression in 652 CRCs using a tissue microarray approach. Correlation with clinicopathological factors including gender, tumour grade, mucinous subtype, TNM stage, disease-specific survival (DSS), BRAF and KRAS mutation status, tumour p53 immunostaining, tumour microsatellite instability and tumour CpG island methylator phenotype was performed. Colorectal cancer cell clones with stable RAD21 knockdown were generated and tested for cellular sensitivity to conventional chemotherapeutic drugs.

Results:

RAD21 expression was significantly correlated with male gender (56.7% vs 43.3%, P=0.02), well-differentiated histology (14.4% vs 4.0%, P=0.0001), higher T-stage (36.1% vs 27.0%, P=0.01), presence of metastasis (18.8% vs 12.6%, P=0.03), and shorter DSS (hazard ratio (HR) 1.4, 95% CI 1.1 to 1.9, P=0.01) in both univariate and multivariate analysis. RAD21 expression was associated with shorter DSS in patients with KRAS mutant tumours (HR:2.6, 95% CI:1.4–4.3, P=0.001) and in patients receiving adjuvant chemoradiotherapy (HR:1.9, 95% CI:1.2–3.0, P=0.008). Colorectal cancer cells with RAD21 knockdown exhibited enhanced sensitivity to 5-fluorouracil, either alone or in combination with oxaliplatin.

Conclusions:

RAD21 expression in CRC is associated with aggressive disease especially in KRAS mutant tumours and resistance to chemoradiotherapy. RAD21 may be an important novel therapeutic target.     

Pre-treatment neutrophil-to-lymphocyte ratio as predictor of adverse outcomes in patients undergoing radical cystectomy for urothelial carcinoma of the bladder

Background:

An elevated neutrophil-to-lymphocyte ratio (NLR) is associated with poor outcome in various tumours. Its prognostic utility in patients with urothelial carcinoma of the bladder (UCB) undergoing radical cystectomy (RC) is yet to be fully elucidated.

Methods:

A cohort of patients undergoing RC for UCB in a tertiary referral centre between 1992 and 2012 was analysed. Neutrophil-to-lymphocyte ratio was computed using complete blood counts performed pre-RC, or before neo-adjuvant chemotherapy where applicable. Time-dependent receiver operating characteristic curves were used to determine the optimal cutoff point for predicting recurrence-free survival (RFS), cancer-specific survival (CSS) and overall survival (OS). The predictive ability of NLR was assessed using Kaplan–Meier analyses and multivariable Cox proportional hazards models. The likelihood-ratio test was used to determine whether multivariable models were improved by including NLR.

Results:

The cohort included 424 patients followed for a median of 58.4 months. An NLR of 3 was determined as the optimal cutoff value. Patients with an NLR⩾3.0 had significantly worse survival outcomes (5y-RFS: 53% vs 64%, log-rank P=0.013; 5y-CSS: 57% vs 75%, log-rank P<0.001; 5y-OS: 43% vs 64%, log-rank P<0.001). After adjusting for disease-specific predictors, an NLR ⩾3.0 was significantly associated with worse RFS (HR=1.49; 95% CI=1.12–2.0, P=0.007), CSS (HR=1.88; 95% CI=1.39–2.54, P<0.001) and OS (average HR=1.67; 95% CI=1.17–2.39, P=0.005). The likelihood-ratio test confirmed that prognostic models were improved by including NLR.

Conclusions:

Neutrophil-to-lymphocyte ratio is an inexpensive prognostic biomarker for patients undergoing RC for UCB. It offers pre-treatment prognostic value in addition to established prognosticators and may be helpful in guiding treatment decisions.     

Ethnicity and outcome of young breast cancer patients in the United Kingdom: the POSH study

Background:

Black ethnic groups have a higher breast cancer mortality than Whites. American studies have identified variations in tumour biology and unequal health-care access as causative factors. We compared tumour pathology, treatment and outcomes in three ethnic groups in young breast cancer patients treated in the United Kingdom.

Methods:

Women aged ⩽40 years at breast cancer diagnosis were recruited to the POSH national cohort study (MREC: 00/06/69). Personal characteristics, tumour pathology and treatment data were collected at diagnosis. Follow-up data were collected annually. Overall survival (OS) and distant relapse-free survival (DRFS) were assessed using Kaplan–Meier curves, and multivariate analyses were performed using Cox regression.

Results:

Ethnicity data were available for 2915 patients including 2690 (91.0%) Whites, 118 (4.0%) Blacks and 87 (2.9%) Asians. Median tumour diameter at presentation was greater in Blacks than Whites (26.0 mm vs 22.0 mm, P=0.0103), and multifocal tumours were more frequent in both Blacks (43.4%) and Asians (37.0%) than Whites (28.9%). ER/PR/HER2-negative tumours were significantly more frequent in Blacks (26.1%) than Whites (18.6%, P=0.043). Use of chemotherapy was similarly high in all ethnic groups (89% B vs 88.6% W vs 89.7% A). A 5-year DRFS was significantly lower in Blacks than Asians (62.8% B vs 77.0% A, P=0.0473) or Whites (62.8 B% vs 77.0% W, P=0.0053) and a 5-year OS for Black patients, 71.1% (95% CI: 61.0–79.1%), was significantly lower than that of Whites (82.4%, 95% CI: 80.8–83.9%, W vs B: P=0.0160). In multivariate analysis, Black ethnicity had an effect on DRFS in oestrogen receptor (ER)-positive patients that is independent of body mass index, tumour size, grade or nodal status, HR: 1.60 (95% CI: 1.03–2.47, P=0.035).

Conclusion:

Despite equal access to health care, young Black women in the United Kingdom have a significantly poorer outcome than White patients. Black ethnicity is an independent risk factor for reduced DRFS particularly in ER-positive patients.     

Randomised phase II study comparing dose-escalated weekly paclitaxel vs standard-dose weekly paclitaxel for patients with previously treated advanced gastric cancer

Background:

This randomised phase II trial compared dose-escalated weekly paclitaxel (wPTX) vs standard-dose wPTX for patients with previously treated advanced gastric cancer (AGC).

Methods:

Ninety patients were randomised to a standard dose of wPTX (80 mg m⁻²) or an escalated dose of wPTX (80–120 mg m⁻²) to assess the superiority of overall survival (OS) with a one-sided alpha error of 0.3 and a power of 0.8.

Results:

The median OS showed a trend towards longer survival in the dose-escalated arm (11.8 vs 9.6 months; hazard ratio (HR), 0.75; one-sided P=0.12), although it was statistically not significant. The median progression-free survival (PFS) was significantly longer in the dose-escalated arm (4.3 vs 2.5 months, HR, 0.55; P=0.017). Objective response rate was 30.3% with dose escalation and 17.1% with standard dose (P=0.2). The frequency of all grades of neutropenia was significantly higher with dose escalation (88.7% vs 60.0%, P=0.002); however, no significant difference was observed in the proportion of patients experiencing grade 3 or more (40.9% vs 31.1%, P=0.34).

Conclusion:

Dose-escalated wPTX in patients with pretreated AGC met our predefined threshold of primary end point, OS (P<0.3); however, it did not show a significantly longer OS. Progression-free survival was significantly better with dose escalation.     

Cediranib with mFOLFOX6 vs bevacizumab with mFOLFOX6 in previously treated metastatic colorectal cancer

Background:

Cediranib is a highly potent inhibitor of vascular endothelial growth factor (VEGF) signalling with activity against all three VEGF receptors. Bevacizumab is an anti-VEGF-A monoclonal antibody with clinical benefit in previously treated metastatic colorectal cancer (mCRC).

Methods:

Patients with mCRC who had progressed following first-line therapy were randomised 1 : 1 : 1 to modified (m)FOLFOX6 plus cediranib (20 or 30 mg day⁻¹) or bevacizumab (10 mg kg⁻¹ every 2 weeks). The primary objective was to compare progression-free survival (PFS) between treatment arms.

Results:

A total of 210 patients were included in the intent-to-treat (ITT) analysis (cediranib 20 mg, n=71; cediranib 30 mg, n=73; bevacizumab, n=66). Median PFS in the cediranib 20 mg, cediranib 30 mg and bevacizumab groups was 5.8, 7.2 and 7.8 months, respectively. There were no statistically significant differences between treatment arms for PFS (cediranib 20 mg vs bevacizumab: HR=1.28 (95% CI, 0.85–1.95; P=0.29); cediranib 30 mg vs bevacizumab: HR=1.17 (95% CI, 0.77–1.76; P=0.79)) or overall survival (OS). Grade ⩾3 adverse events were more common with cediranib 30 mg (91.8%) vs cediranib 20 mg (81.4%) or bevacizumab (84.8%).

Conclusion:

There were no statistically significant differences between treatment arms for PFS or OS. When combined with mFOLFOX6, the 20 mg day⁻¹ dose of cediranib was better tolerated than the 30 mg day⁻¹ dose.     

VEGF-A polymorphisms predict progression-free survival among advanced castration-resistant prostate cancer patients treated with metronomic cyclophosphamide

Background:

No data are available on the pharmacogenetics of metronomic chemotherapy in prostate cancer. The aim of this study was to evaluate the association between VEGF-A sequence variants and prostate-specific antigen (PSA) progression, progression-free survival (PFS) and overall survival (OS), in advanced castration-resistant prostate cancer patients treated with metronomic cyclophosphamide (CTX), celecoxib and dexamethasone.

Methods:

Forty-three patients were enrolled, and genomic DNA was extracted. VEGF-A gene SNPs (−2578A/C, −634C/G, +936C/T) were analysed using TaqMan PCR assays. Hardy–Weinberg equilibrium was tested for each SNP, and genetic effects were evaluated by Fisher''s exact test. PFS and OS were analysed with GraphPad Prism software, using the product limit method of Kaplan and Meier, and comparing survival curves using both the log-rank test and the Gehan–Wilcoxon test. We used Bonferroni correction to account for multiple testing, and a two-tailed P-value of <0.017 was considered statistically significant.

Results:

Overall, 20 patients (46%) experienced a reduction in PSA levels from baseline and, among them, 14 (32%) showed a confirmed PSA ≥50% decrease. In non-responders, the −2578CC genotype was more frequent (18.60% vs 2.33% in responders; P=0.0212) whereas the −634CC genotype frequency was 22.73% vs 0% in responders (P=0.0485). With regard to PFS, patients harbouring the −634CC genotype had a median PFS of 2.2 months whereas patients with the genotype −634CG/GG had a median PFS of 6.25 months (P=0.0042).

Conclusion:

The −634CC genotype is significantly associated with a shorter PFS in patients treated with a metronomic CTX schedule.     

BRAF mutations,microsatellite instability status and cyclin D1 expression predict metastatic colorectal patients' outcome

Background:

The significance of BRAF mutations, microsatelite instability (MSI) status and cyclin D1 expression in patients with metastatic colorectal cancer (mCRC) was evaluated.

Methods:

Primary tumours from 144 patients treated for mCRC were assessed for BRAF (V600E) mutation, MSI status and cyclin D1. The data were correlated with progression-free survival (PFS) and overall survival (OS).

Results:

BRAF mutations were detected in 10 (out of 22, 45%) patients with MSI-H tumours compared with 2 (out of 122, 1.6%) in those with microsatellite stable tumours (P<0.001). The presence of BRAF mutations was correlated with cyclin D1 overexpression (7 out of 26 patients, 58% vs 5 out of 118 patients, 14% P=0.001). Patients with BRAF-mutated primary tumours had a significantly decreased PFS (2.7 vs 9.8 months; P<0.001) and median OS (14 vs 30 months; P<0.001) than patients with wild-type (wt) tumours. Patients with MSI-H and BRAF-mutated tumours experienced significantly lower PFS (3.1 vs 11.4 months; P=0.008) and OS (14.5 vs 35.5 months; P=0.004) than patients with MSI-H and BRAF wt tumours. Similarly, BRAF mutations and cyclin D1 overexpression were correlated with decreased PFS (3.1 vs 8.6 months; P=0.03) and OS (17.8 vs 39.2 months; P=0.01).

Conclusion:

BRAF V600E mutations are associated with MSI-H status and cyclin D1 overexpression and characterize a subgroup of patients with poor prognosis.     

Phosphorylated protein phosphatase 2A determines poor outcome in patients with metastatic colorectal cancer

Background:

Protein phosphatase 2A (PP2A) is a tumour suppressor frequently inactivated in human cancer and its tyrosine-307 phosphorylation has been reported as a molecular inhibitory mechanism.

Methods:

Expression of phosphorylated PP2A (p-PP2A) was evaluated in 250 metastatic colorectal cancer (CRC) patients. Chi-square, Kaplan–Meier and Cox analyses were used to determine correlations with clinical and molecular parameters and impact on clinical outcomes.

Results:

High p-PP2A levels were found in 17.2% cases and were associated with ECOG performance status (P=0.001) and presence of synchronous metastasis at diagnosis (P=0.035). This subgroup showed substantially worse overall survival (OS) (median OS, 6.0 vs 26.2 months, P<0.001) and progression-free survival (PFS) (median PFS, 3.8 vs 13.3 months, P<0.001). The prognostic impact of p-PP2A was particularly evident in patients aged <70 years (P<0.001). Multivariate analysis revealed that p-PP2A retained its prognostic impact for OS (hazard ratio 2.7; 95% confidence interval, 1.8–4.1; P<0.001) and PFS (hazard ratio 3.0; 95% confidence interval, 1.8–5.0; P<0.001).

Conclusions:

Phosphorylated PP2A is an alteration that determines poor outcome in metastatic CRC and represents a novel potential therapeutic target in this disease, thus enabling to define a subgroup of patients who could benefit from future treatments based on PP2A activators.     

The preoperative lymphocyte to monocyte ratio predicts clinical outcome in patients with stage III colon cancer

Background:

Inflammation has a critical role in the pathogenesis and progression of cancer. The lymphocyte to monocyte ratio (LMR) could be shown to be prognostic in haematologic neoplasia. In this study, we analysed the LMR with clinical outcome in stage II and III colon cancer patients.

Methods:

Three hundred and seventy-two patients with stage II and III colon cancer were included in this retrospective study. Kaplan–Meier curves and multivariate Cox-regression analyses were calculated for time to recurrence (TTR) and overall survival (OS).

Results:

Including all patients, the elevated preoperative LMR was significantly associated with increased TTR and OS in multivariate analysis (HR: 0.47, 95%CI: 0.29–0.76, P=0.002; HR: 0.51, 95%CI: 0.31–0.83, P=0.007; respectively). In subanalyses, the association was limited to patients with stage III (HR: 0.40, 95%CI: 0.22–0.72, P=0.002), in contrast to patients with stage II (HR: 0.40, 95%CI: 0.28–1.66, P=0.397). When the subgroup of patients with ‘high-risk'' LMR⩽2.83 was analysed, no benefit of adjuvant 5-FU-based chemotherapy could be found (HR: 0.99; 95%CI: 0.60–1.63; P=0.953).

Conclusion:

The LMR might be an independent prognostic marker for TTR in stage III colon cancer patients. Our results further suggest that high-risk patients based on the LMR do not benefit from adjuvant chemotherapy. Independent validation of our findings is warranted.     

Sorafenib in advanced melanoma: a critical role for pharmacokinetics?

Background:

Inter-patient pharmacokinetic variability can lead to suboptimal drug exposure, and therefore might impact the efficacy of sorafenib. This study reports long-term pharmacokinetic monitoring of patients treated with sorafenib and a retrospective pharmacodynamic/pharmacokinetic analysis in melanoma patients.

Patients and methods:

Heavily pretreated patients with stage IV melanoma were started on sorafenib 400 mg twice daily (bid). In the absence of limiting toxicity, dose escalation of 200 mg bid levels was done every 2 weeks. Plasma sorafenib measurement was performed at each visit, allowing a retrospective pharmacodynamic/pharmacokinetic analysis for safety and efficacy.

Results:

In all, 19 of 30 patients underwent dose escalation over 400 mg bid, and 28 were evaluable for response. The overall disease control rate was 61% (95% confidence interval (CI): 42.6–78.8), including three confirmed responses (12%). Disease control rate and progression-free survival (PFS) were improved in patients with high vs low exposure (80% vs 32%, P=0.02, and 5.25 vs 2.5 months, P=0.005, hazard ratio (HR)=0.28 (95% CI: 0.11–0.73)). In contrast, drug dosing had no effect on PFS. In multivariate analysis, drug exposure was the only factor associated with PFS (HR=0.36 (95% CI: 0.13–0.99)). Diarrhoea and anorexia were correlated with drug dosing, while hypertension and hand–foot skin reaction were correlated with drug exposure.

Conclusions:

Although sorafenib had modest efficacy in melanoma, these results suggest a correlation between exposure and efficacy of sorafenib. Therefore, dose optimisation in patients with low exposure at standard doses should be evaluated in validated indications.     

Correlation of extended RAS and PIK3CA gene mutation status with outcomes from the phase III AGITG MAX STUDY involving capecitabine alone or in combination with bevacizumab plus or minus mitomycin C in advanced colorectal cancer

Background:

Mutations affecting RAS genes are now established predictive markers of nonresponse to anti-EGFR antibodies in advanced CRC. This analysis assessed the prognostic and predictive impact of extended RAS and PIK3CA gene mutation status in patients receiving capecitabine plus or minus bevacizumab (±mitomycin C) in the randomised phase III MAX study.

Methods:

DNA was extracted from archival macrodissected formalin-fixed paraffin-embedded tumour tissue. Mutation status was determined using pyrosequencing, confirmed with Sanger sequencing (for equivocal RAS) and correlated with efficacy outcomes. Predictive analyses were undertaken using a test for interaction involving both C vs CB+CBM.

Results:

Of the available 280 of the 471 (59.4%) patients, mutations in KRAS exons 2, 3 and 4 and NRAS 2, 3 and 4 were as follows: 32%, 2.9%, 2.2%, 1.4%, 0.7% and 0% (total RAS MT 39%). The PIK3CA MT rate was 7.5% exon 9 and 3.6% exon 20. Extended RAS gene mutation status (WT vs MT) had no prognostic impact for PFS (HR 0.91 (0.71–1.17)) or OS (HR 0.95 (0.71–1.25)). The RAS gene mutation status was not predictive of the effectiveness of bevacizumab for PFS (HR 0.56 (0.37–0.85) for RAS MT and HR 0.69 (0.5–0.97) for RAS WT; P for interaction 0.50). The PIK3CA mutation was neither predictive for bevacizumab effect nor prognostic.

Conclusion:

Of KRAS exon 2 WT patients, 10% had additional RAS mutations. Neither all RAS gene mutation status nor PIK3CA mutation status was prognostic for PFS or OS, or predictive of bevacizumab outcome in patients with advanced CRC.