Phase II study of a polyethoxylated castor oil–free, polymeric micelle formulation of paclitaxel for patients with advanced urothelial cancer previously treated with gemcitabine and platinum

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Background: Paclitaxel-loaded polymeric micelle (Genexol-PM; G-PM) is a novel polyethoxylated castor oil (Cremophor EL [CrEL])-free formulation of paclitaxel. This multicenter phase II study was designed to evaluate the efficacy and safety of the G-PM monotherapy for the treatment of gemcitabine- and cisplatin-refractory advanced urothelial cancer.

Methods: Patients with advanced urothelial cancer received G-PM 240 mg/m2 intravenously over 3 hours every 3 weeks without premedication as salvage chemotherapy after failure to gemcitabine and cisplatin combination chemotherapy. Intrapatient dose escalation of G-PM to 300 mg/m2 was carried out from the second cycle if the prespecified toxicities were not observed after the first cycle.

Results: Thirty-seven patients were enrolled in this study. Platinum-free interval was less than 6 months in 72% of patients and 64% of patients were categorized into intermediate or poor prognostic group. Overall response rate was 19% including one complete response. When response occurs it is long lasting with a median response duration of 7.8 months (range 1.5∼19.3+). The median progression-free survival was 2.7 months (95% CI, 09-4.6) with a median overall survival of 5.7 months (95% CI, 3.1-8.3). The most common major grade 3-4 non-hematologic toxicity was peripheral neuropathy (sensory type 5.6% and motor type 8.3%) followed by infection (5.6%). Grade 3 or worse hematologic toxicities were observed in only one patient.

Conclusions: G-PM showed modest activity with favorable toxicity profiles when used as salvage therapy after gemcitabine-cisplatin failure in advanced urothelial cancer.

No significant financial relationships to disclose.

Multicenter prospective phase II study of sunitinib in non-clear cell type renal cell carcinoma

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Background: Sunitinib has been shown to produce a high response rate (RR), and improved progression-free survival (PFS) in patients (pts) with clear cell RCC. Retrospective data suggest sunitinib may be effective in papillary and chromophobe RCC. We conducted a multicenter phase II trial of sunitinib in non-clear cell RCC (nccRCC).

Methods: Eligibility criteria included PS 0-1, measurable disease, and adequate organ function. Pts with brain metastases were not excluded if controlled without steroid dependence. Response assessment was performed every 6 weeks. Primary endpoint was RR. Secondary endpoints were TTP, safety and OS.

Results: Between 6/2008 and 7/2010, 29 pts with nccRCC were enrolled (total accrual 35: P0=5%, P1=20%, alpha=0.05, beta=0.2, drop-out rate 15%). Median age was 52 (18–76). Twenty-four pts (84%) had prior nephrectomy. Seven pts (24%) had poor risk and 13 (45%) had intermediate risk disease by MSKCC criteria. Twenty-one pts had papillary RCC (type II in 11 and type not- specified in 10), and 4 patients had chromophobe RCC. Two pts discontinued protocol treatment due to toxicity prior to completion of cycle 1 (one pt had cardiogenic shock 27 days after start of therapy and the other refused further treatment 5 days after therapy). Eleven pts out of 29 had partial response with a RR of 38% (95% CI, 20.2%–55.6%) and additional 15 patients (52%) had SD with a disease control rate of 90%. Response rates were not significantly different according to the histologic type (43% in papillary type and 25% in chromophobe type). Median duration of response was 12.7 months (95% CI, 2.3∼23.1) and median TTP was 6.4 months (95% CI, 4.5∼8.3). With a median FU duration of 16 months (95% CI, 8.6∼23.4), 10 pts have been dead resulting in an estimated median OS of 17.9 months. Toxicity profiles were commensurate with prior reports on Korean patients (Yoo, et al. Jpn J Clin Oncol 2010). However, there was one treatment-related death caused by acute heart failure in patient without relevant risk factors for heart disease.

Conclusions: Although our study is ongoing, the primary endpoint has been met and these data suggest that suntinib has promising activity in patients with nccRCC.

No significant financial relationships to disclose.

Application of Western patients-based Adjuvant! Online (AOL) model on Korean colon cancer patients

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Background: Adjuvant! Online (AOL) is a web-accessible risk-assessment model that predicts the mortality and the benefits of adjuvant therapy ( www.adjuvantonline.org ). AOL has never been validated for Asian colon cancer patients.

Methods: Using the Yonsei Tumor Registry (YTR) database, we calculated the survival for the patients with T1-4, N0-2, M0 colon cancer who were treated at the Yonsei Cancer Center between 1990 and 2005. Observed and predicted 5-year survival was compared for each patient.

Results: The median age of the study population was 60 years (range, 15-87 years) and the median follow-up duration was 7.9 years (range, 0.06-19.8 years) for all 1,431 patients. While AOL underestimate overall survival (OS) (predicted-observed=-1.02%, P=0.008), it overestimate colon cancer-specific survival (CCSS) (predicted-observed=3.8%, P<0.001) in Korean patients. Especially, AOL underestimated OS and CCSS in younger patients than age 50 years (predicted-observed=-4.3%, P<0.001 and predicted-observed=-3.5%, P<0.001, respectively). We conducted an internal model validation by using a Korean version of AOL (KAOL), which was a new model for prognosis based on AOL's parameters. 5-year OS and CCSS between the observed and the KAOL predicted survival were not different (77.25 vs. 77.15, P=0.873 and 77.4% vs. 77.6%, P=0.78, respectively). The concordance indexes about OS and CCSS were 0.75 and 0.74, respectively.

Conclusions: KAOL model for Korean colon cancer patients is more suitable to predict 5-year outcomes compared to ALO model for Western patients.

No significant financial relationships to disclose.

Gene-expression profiles related to a synergistic effect of taxane and suberoylanilide hydroxamic acid combination treatment in gastric cancer cells

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Background: We evaluated the cytotoxic effects of combining of suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, with taxanes in human gastric cancer cell lines, and evaluated the pre-treatment difference of gene profile to identify genes that could potentially mediate the cytotoxic response.

Methods: Twenty-five gastric cancer cell lines with 22K gene expression data were treated with SAHA and paclitaxel or docetaxel, and the synergistic interaction between the drugs was evaluated in vitro using the combination index (CI) method. We performed significance analysis of microarray (SAM) to identify chemosensitivity-related genes in gastric cancer cell lines that were concomitantly treated with SAHA and taxane. We generated a correlation-matrix between gene expression and CI values to identify genes whose expression correlated with a combined effect of taxanes and SAHA.

Results: Taxane and SAHA combination had a synergistic cytotoxic effect against taxane-resistant gastric cancer cells. We selected 49 chemosensitivity-related genes, which were commonly identified in paclitaxel and docetaxel combined with SAHA, via SAM analysis. Among them, nine common genes (SLIT2, REEP2, EFEMP2, CDC42SE1, FSD1, POU1F1, ZNF79, ETNK1, and DOCK5) were extracted from the subsequent correlation-matrix analysis.

Conclusions: Taxane and SAHA combination could be efficacious for the treatment of gastric cancer. The genes which were related with the synergistic response to taxane and SAHA could serve as surrogate biomarkers to predict the therapeutic response in gastric cancer patients. We are researching to determine the expression of the nine genes in malignant human gastric cancer tissue and to correlate them with clinical information.

No significant financial relationships to disclose.

Use of class III beta tubulin to predict efficacy from paclitaxel- or docetaxel-based chemotherapy in patients with advanced gastric cancer

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Background: To predict clinical outcome in patients with advanced gastric cancer (AGC) received paclitaxel or docetaxel based chemotherapy, we evaluated expression of class III beta tubulin (bTubIII).

Methods: Expression of bTubIII was evaluated by immunohistochemistry (IHC) on formalin-fixed, paraffin-embedded tumors from the primary gastric cancer. Tumors were classified as bTubIII “low” and “high” according to median of IHC score [intensity (0-3) × portion (0-100)]. The expression of bTubIII was investigated for their association with clinical outcomes of efficacy and toxicity.

Results: One hundred twenty-four AGC pts who were treated with paclitaxel or docetaxel combined with an infusional 5-fluorouracil and low-dose leucovorin as first and second-line palliative chemotherapy were enrolled. Thirty-three patients (26.7%) were confirmed to have high expression of bTubIII. The patients with high expression of bTubIII showed higher disease control rate (DCR) and longer progression-free survival (PFS) than those with low expression in patients treated with paclitaxel (79.3 % vs. 57.3 %, p = 0.039, and 3.0 months vs. 1.5 months, p = 0.073). By contrast, there was no difference of DCR and PFS according to expression of bTubIII in patients treated with docetaxel. The expression of bTubIII was not associated with toxicity in both patients treated with paclitaxel or docetaxel.

Conclusions: The expression of bTubIII may be a predictive marker in AGC patients received paclitaxel based chemotherapy, but not docetaxel.

No significant financial relationships to disclose.

Low vitamin D status is associated with physical inactivity, obesity and low vitamin D intake in a large US sample of healthy middle-aged men and women

The aim of this study was to investigate modifiable predictors of vitamin D status in healthy individuals, aged 55-74, and living across the USA. Vitamin D status [serum 25-hydroxyvitamin D (25(OH)D)] was measured along with age and season at blood collection, demographics, anthropometry, physical activity (PA), diet, and other lifestyle factors in 1357 male and 1264 female controls selected from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) cohort. Multivariate linear and logistic regression analyses were used to identify associations with vitamin D status. Three%, 29% and 79% of the population had serum 25(OH)D levels<25, <50 and <80 nmol/L, respectively. The major modifiable predictors of low vitamin D status were low vitamin D dietary and supplement intake, body mass index (BMI) >30 kg/m2, physical inactivity (PA) and low milk and calcium supplement intake. In men, 25(OH)D was determined more by milk intake on cereal and in women, by vitamin D and calcium supplement and menopausal hormone therapy (MHT) use. Thus targeting an increase in vigorous activity and vitamin D and calcium intake and decreasing obesity could be public health interventions independent of sun exposure to improve vitamin D status in middle-aged Americans.