Phase I dose escalation trial of sorafenib as a single agent for adults with relapsed and refractory acute leukemias

7065

Background: Sorafenib is a multikinase inhibitor with activity against B-raf, VEGF, and FLT3. Based on preclinical activity in FLT3 mutant AML, sorafenib was studied in refractory acute leukemia. Methods: The primary objective was to determine the safety and tolerability of sorafenib in refractory acute leukemias. Secondary objectives included pharmacokinetics (PK) and pharmacodynamic (PD) effects of sorafenib on FLT3 phosphorylation. Dose escalation began at 400 mg BIDx14days per month, and proceeded through 600 mg BID x 21 days per month. Plasma concentration of sorafenib and its primary metabolite sorafenib N-oxide were measured by LC/MS//MS method. The plasma inhibitory assay was used to measure target inhibition of phosphorylated FLT3 and phosphorylated Erk. Results: Fifteen patients (13 = AML, 2 = ALL) were enrolled (ages 37–85) and treated on three dosing schedules (400 mg BID x 14 d, 400 mg BID x 21 days, 600 mg BID x 21days) of single agent sorafenib. The maximally tolerated dose was 400 mg BID x 21 days per month. Grade 3 or greater toxicities were experienced in 55% of cycles, most common grade 3 or greater toxicities being fatigue (16%) and hypokalemia (13%). No patients met criteria for complete or partial response, but 11 of 15 (73%) patients experienced stable disease as best response, with 6 showing a reduction in bone marrow blasts after only one cycle, half of who experienced a >50% reduction in bone marrow blasts. Interestingly, 2 pts with FLT3-ITD mutations both showed marrow blast response (1 pt >50%). Sorafenib resulted in sustained complete inhibition of FLT3 and Erk as demonstrated in all patients assessed (n = 11). Importantly, this inhibition was maintained throughout treatment cycle and 3/5 pts had FLT3 inhibitory activity 7 days post their last dose. Correlative studies suggest sorafenib N-oxide is an active metabolite. Conclusions: Sorafenib is a potent inhibitor of FLT3 with favorable PK and PD properties. Clinical activity as a single agent was limited to transient reductions in bone marrow blast counts and dose escalation was limited due to toxicities. Based on PK data in conjunction with standard curves for inhibition of FLT3 by sorafenib in plasma, the minimum FLT3 inhibitory dose of sorafenib is likely less than 400 mg BID.

No significant financial relationships to disclose.

A multinational phase III randomized trial with or without consolidation chemotherapy using docetaxel and cisplatin after concurrent chemoradiation in inoperable stage III non-small cell lung cancer (CCheIN): Interim analysis

7538

Background: Currently, the recommended treatment for inoperable stage III non-small cell lung cancer (NSCLC) is concurrent chemoradiotherapy (CCRT). The efficacy of consolidation chemotherapy after CCRT needs to be confirmed. The aim of this phase III randomized trial is to determine the efficacy of consolidation chemotherapy with docetaxel (D) and cisplatin (P) following definitive CCRT with the same agents in stage III inoperable NSCLC. Herein we report the pre-planned interim analysis. Methods: Patients with inoperable stage III NSCLC were randomized to either CCRT alone (observation arm) or CCRT followed by consolidation chemotherapy (consolidation arm). N2 or N3 disease was confirmed by PET and/or pathology. CCRT with D (20 mg/m2) and P (20 mg/m2) was administered every week for 6 weeks with a total dose of 66 Gy of thoracic RT as 33 fractions. In the consolidation arm, patients were further treated with 3 cycles of D and P (35 mg/m2 each on day 1 and 8, every 3 weeks). The primary endpoint is time to progression (TTP). Total target number of patients is 458. Results: From Oct 2005 to Mar 2008, 233 patients were enrolled and 226 were randomized (observation 112; consolidation 114). Patients’ characteristics were similar in both arms. In the consolidation arm, 83 patients (73%) received consolidation chemotherapy, of whom 52 (45%) completed 3 planned cycles. Grade 3–4 neutropenia occurred in 5.4% of 203 consolidation cycles. Common non-hematologic toxicities of all grades during consolidation were anorexia (47%), nausea (37%), vomiting (16%), fatigue (35%) and esophagitis (31%). At the time of this analysis, there were 40 and 41 deaths in the observation and consolidation arms, respectively. Treatment-related mortality rates were similar. With a median follow-up of 28.2 months, the median TTP was 9.0 months in the observation arm and 13.9 months in the consolidation arm (P=0.19). Median overall survival was 20.7 and 21.2 months, respectively (P=0.49). Conclusions: This interim analysis suggests that consolidation chemotherapy with DP after CCRT with weekly DP is feasible and relatively well tolerated. Patient enrollment is ongoing.

No significant financial relationships to disclose.

A randomized phase II trial of weekly docetaxel plus either cisplatin or oxaliplatin in patients with previously untreated advanced gastric cancer: Preliminary results

4566

Background: Docetaxel, in combination with cisplatin or oxaliplatin, has demonstrated efficacy against AGC. This randomized phase II trial evaluated two weekly docetaxel-based regimens to see which would be most promising according to objective response rate (ORR) as first-line therapy in AGC. Methods: Chemotherapy-naïve patients with measurable unresectable and/or metastatic gastric adenocarcinoma and a performance status ≤2 were randomly assigned to receive docetaxel (35 mg/m2) weekly on days 1 and 8 of a 21-day cycle plus either cisplatin (60 mg/m2 on day 1) (arm A) or oxaliplatin (120 mg/m2 on day 1) (arm B). Toxicity was assessed on days 1, 8, and 21 of each cycle, and response was evaluated every 2 cycles. Results: Between March 2007 and December 2008, 61 eligible patients entered. In Arm A, 29 patients were evaluable for objective response and 31 for safety. In Arm B, 28 patients were evaluable for objective response and 30 for safety. Median age was 52 years and disease status was comparable for both arms. Ten of 29 (34.5%) patients had a confirmed objective response in the arm A (95% confidence interval [CI] 17.1–51.8%) and 11 of 28 (39.2%) patients had a confirmed objective response in the arm B (95% CI 21.1- 57.2%). No significant difference was noted between the arms both for ORR (p=0.202) or for disease control (58.6% and 82.1%, respectively, p=0.082). Median progression free survival time was 4.4 month in the arm A and 4.3 months in the arm B (Hazard ratio = 0.936; 95% CI, 0.503–1.744; p = 0.836). There was no relevant difference in the occurrence of overall grade ¾ toxicity between the two arms (51.6% vs. 46.6%, respectively; p=0.800). Neutropenia was the most common grade 3/4 toxicity (32.3% vs. 36.6%, respectively). There was one treatment related death in Arm B. Conclusions: The preliminary results showed that both treatment arms have similar clinical efficacy as front-line treatment in AGC. Each regimen has a manageable tolerability profile. The accrual is ongoing.

No significant financial relationships to disclose.

Risk stratification by hormonal receptor (ER, PgR) and HER2 status in small (≤1cm) invasive breast cancer: Who might be a possible candidate for adjuvant treatment?

564

Background: With the increasing use of screening mammography, the proportion of ≤ 1 cm invasive breast cancer is increasing. Identification of breast cancer molecular subtypes has resulted in a better appreciation of the biologic heterogeneity, which is not fully explained by clinicopathologic features including staging system. The aims of this study were: 1) to identify the risk factors of systemic metastases in patients with ≤ 1 cm invasive breast cancer and 2) to investigate the patients group at greatest risk of such failure even in these small tumors. Method: Data were collected retrospectively in the breast cancer registry of our institution for patients with invasive breast cancer from October 1994 to December 2004. Results: Of 4,036 patients who received curative breast cancer surgery, 466 patients who had T1a or T1b breast cancer were identified. 39 patients who received neoadjuvant chemotherapy were excluded in this study. Ipsilateral axillary lymph node involvement was found in 13% (57/427) at the time of surgery. Axillary lymph node involvement was much more common in HER-2 positive group (33% vs 11%, p < 0.0001) and triple negative (TN) group (24% vs 11%, p = 0.002) than in hormone receptor positive group. During median 61 months of follow-up, overall 10 year estimated distant relapse-free survival (DRFS) and overall survival (OS) were 95% and 92%, respectively. Multivariate analysis was conducted in 370 (T1aN0, T1bN0) patients, who had no lymph node involvement. In Cox-regression model, HER-2 positivity and triple negativity were identified as independent prognostic factors to predict DRFS [Hazard ratio (HR) 8.8, p = 0.003 for HER-2 positive group; HR 5.1, p = 0.026 for TN group] and OS (HR 5.0, p = 0.067 for HER-2 positive group; HR 11.1, p = 0.017 for TN group) in T1bN0 tumors. Limiting to T1aN0 tumors, statistical significance was not maintained. Conclusions: Even though T1aN0 and T1bN0 tumors have been known to have a relative low risk of systemic failure, anti-HER-2 directed therapy for HER-2 positive group and new innovative adjuvant systemic treatment for TN group in patients with T1bN0 tumor should be considered. Prospective adjuvant trials should be warranted in these subgroups of patients.

No significant financial relationships to disclose.

Building a backlight unit with lateral gate structure based on carbon nanotube field emitters

This paper describes the fabrication of a backlight unit for liquid crystal display based on printed carbon nanotube field emitters with lateral gate and additional mesh structures. The device architecture has been optimized through field emission characterization and supporting numerical simulation. The emission current depends strongly on the cathode-gate gap, mesh position, and mesh bias. Direct observation of luminous images on a phosphor screen reveals that the electron beams undergo a noticeable shrinkage along the lateral direction with increasing anode bias, which is in good agreement with the simulation results. We suggest and demonstrate a modified structure equipped with double emitter edges leading to approximately 20% improved phosphor efficiency (34.4 lm W(-1)) and luminance (9600 cd m(-2)), compared to those from a single edge structure.

Metastasis-associated microtentacles are induced in detached and circulating breast tumor cells by expression of the microtubule-binding protein, Tau

Abstract #55

Detached human breast tumor cell lines produce microtentacles composed of a unique kinesin-dependent coordination of vimentin filaments and detyrosinated microtubules. Compelling in vivo studies show that a mechanism consistent with microtentacles is responsible for the attachment of circulating tumor cells to blood vessel walls. However, the molecular regulators of microtentacle extension have only begun to be defined. Increased expression of the microtubule-binding protein, Tau, is associated with poor patient outcome in breast cancer, but the mechanism by which Tau protein affects prognosis remains unclear. We report here that expression of Tau directly regulates the formation of metastasis-associated microtentacles in detached and circulating breast tumor cells. First, increased expression of Tau correlates with increased microtentacle frequency in a panel of human breast tumor cell lines. Endogenous Tau protein colocalizes with tubulin microtentacles in cells detached from extracellular matrix. Exogenous expression of Tau significantly increases microtentacle frequency in weakly invasive breast tumor cell lines. Tau-induced microtentacles are longer, thicker and more rigid than those in cell lines without Tau expression. Although there is increasing interest in targeting the actin cytoskeleton to reduce tumor cell motility and division, our results indicate that breast tumor cells with high Tau expression have particularly dramatic increases in microtentacles when treated with inhibitors of actin polymerization. Likewise, tubulin-stabilizing compounds, like paclitaxel, increase microtentacles and may be ill-advised in patients with high Tau expression. Indeed, clinical studies show that high Tau expression increases the likelihood of recurrence following paclitaxel treatment. We observed an enrichment of Tau in metastatic tumors compared to matched primary tumors. So while stabilizing microtubules and disrupting actin filaments can each decrease tumor cell growth, it is important to consider the effects of these treatments on Tau-expressing cells to avoid accidentally enhancing the metastatic potential of circulating tumor cells while targeting cell division.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 55.

Evaluation of response to neoadjuvant chemotherapy in primary breast cancer using PET

Abstract #4019

Purpose&#x2028; To estimate the usefulness of PET scan to assess the response of neoadjuvant chemotherapy, PET scan results were compared with conventional imaging modalities(US and MRI).&#x2028; Patients and Methods&#x2028; Fourty-one patients undergoing neoadjuvant chemotherapy between December 2004 and March 2008 were included. PET scan was performed before and after chemotherapy. Pathologic results were classified into two groups; pathological complete response(pCR) and non-pCR. Clinical responses were assessed with the results of imaging modalities such as post-chemotherapy size or pSUV(postTx), size difference between treatment(delta) and reduction rate(RR) of size or pSUV, and they are compared with postoperative pathologic results.&#x2028; Results&#x2028; 7 out of 41 patients (17.1%) had pCR. The results of US shows that postTx size (1.7±1.5cm) of pCR was not dfferent from those of non-pCR (3.6±3.0cm), and the delta (3.1±1.9cm) and RR (67.7±29.1%) of pCR were higher than those of non-pCR (1.3±1.3cm, 31.0±25.4%), respectively. As a result of MRI, postTx size, delta, RR of pCR was differ from those of non-pCR (1.0±1.7cm vs 2.8±1.7cm p&lt;0.05; 4.5±1.0cm vs 2.3±1.8cm, p&lt;0.05; 88.0±20.8% vs 44.6±24.7%, p&lt;0.01). In PET scan, only postTx pSUV of pCR was differ from that of non-pCR (1.4±1.3 vs 5.3±8.3cm, p&lt;0.05). As a result of receiver operating characteristic curve analyses for the prediction of pathological response of breast cancer, area under curve values (95% confidence interval) of US, MRI, PET for delta were 0.83(0.69∼0.98), 0.91(0.80∼1.01), 0.62(0.38∼0.86), and those of RR were 0.80(0.60∼0.99), 0.90(0.77∼1.02), 0.72(0.47∼0.96), respectively&#x2028; Conclusions&#x2028; We suggest that MRI is useful method to evaluate the response of neoadjuvant chemotherapy. Although PET scan shows less effective for evaluating the response of chemotherapy than MRI, PET scan with the ability to detect the distant metastatic lesions may be helpful to decide the proper management plans for advanced breast cancer.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4019.

Second-line therapy with irinotecan or gefitinib in docetaxel pretreated patients with non-small cell lung cancer: A new treatment strategy according to clinical predictors for response

18026

Background: Retrospective analyses of previous trials have shown the clinical advantage of gefitinib in advanced non-small cell lung cancer (NSCLC) patients with certain favorable baseline factors (Asian ethnicity, female, adenocarcinoma, or no smoking history). This prospective phase II study was designed to test the hypothesis that higher response rates might be achieved if patients are selected according to these clinical predictors for response. Methods: Korean NSCLC patients who have failed after docetaxel-based first-line chemotherapy were consecutively accrued. Patients without any of the favorable clinical predictors (i.e., male smoker with non-adenocarcinoma) received irinotecan 100 mg/m2 on days 1, 8 and 15 every 4 weeks (irinotecan arm). Patients who had at least one of the predictors for response received gefitinib 250 mg/d orally from day 1 (gefitinib arm). Primary endpoint was response rate. With a two-stage phase II design, the required number of patients was at least 25 per each arm. Results: Of 68 patients accrued, 25 were treated with irinotecan and 43 with gefitinib. In the gefitinib arm, 22 patients were female, 20 were never-smoker, and 33 had adenocarcinoma. Treatment duration was significantly longer in the gefitinib arm (2.0 months for irinotecan arm v 4.4 months for gefitinib arm; p<0.01). Median number of chemotherapy cycles was 2 (range, 1–4) for irinotecan arm. Fewer drug-related toxicities were observed with gefitinib compared with irinotecan. In the irinotecan and gefitinib arm, 28% and 13% of patients, respectively, discontinued treatment because of toxicity. The objective responses of irinotecan and gefitinib arm were 16% (95% CI, 2–30) and 37% (95% CI, 21–51), respectively (p=0.07). Patients in the gefitinib arm had a longer, although statistically insignificant (p=0.11), progression-free survival (6.5 months; 95% CI, 3.8–9.2) than those in the irinotecan arm (3.2 months; 95% CI, 2.0–4.4). Conclusions: Gefitinib could be a reasonable second-line option in Korean NSCLC patients who had at least one favorable clinical predictor. Updated results, including an exploratory analysis of molecular characterization, will be presented.

No significant financial relationships to disclose.

Comprehensive analysis of ERCC, XPD, and XRCC polymorphisms: Association with clinical outcomes in patients with advanced gastric cancer

4649

Background: Platinum-DNA adducts are repaired by nucleotide excision repair (NER) pathway, in which genes of the excision repair cross-complementation 1 (ERCC1), xeroderma pigmentosum group D (XPD) and X-ray repair cross-complementing group (XRCC) have an important role. The purpose of this study was to investigate the relationship between single nucleotide polymorphisms (SNPs) of these genes and the clinical outcomes to combination chemotherapy of 5-FU and oxaliplatin in advanced gastric cancer (AGC). Methods: We searched SNPs of NER pathway genes from database of the International Hapmap Project. Tagging SNPs and halpotype blocks were founded by linakage disequilibrium and haplotype analysis. Whole blood samples were obtained from the patients before chemotherapy. DNA was extracted from the peripheral blood mononuclear cells and the genotyping was performed by SNaPshot methods. Seventy three metastatic or relapsed AGC patients received modified FOLFOX-6 as a first-line palliative chemotherapy and were analyzed. Results: By searching the database of the International Hapmap Project, we found 17 SNPs in ERCC, 69 SNPs in XPD, 78 SNPs in XRCC. We found that some SNPs played a role as a tagging SNP and belonged to haplotype block (5 tapping SNPs and one haplotype block in ERCC, 8 tapping SNPs and two haplotype blocks in XPD, 9 tapping SNPs and two haplotype block in XRCC). Tagging SNPs were analyzed and matched with clinical significance. Among the 22 tagging SNPs of NER pathway genes, only XPD-C156A SNP (rs238406) showed clinical correlation. AA genotype of XPD C156A showed higher response rate (CC: CA: AA= 29.2%: 43.3%: 63.2%, p=0.083) and toxicities (neutropenia of grade 3 or 4) (CC: CA: AA= 4.3%: 3.2%: 21.1%, p=0.060) than CC or CA genotypes. Conclusions: Our results suggest that some SNPs of ERCC, XPD and XRCC showed linkage disequilibrium and belonged to haplotype blocks. And XPD-C156A SNP showed clinical correlation in AGC patients treated with modified FOLFOX-6 regimen. These findings require independent prospective confirmation.

[Table: see text]

Randomized phase II trial of irinotecan, leucovorin and 5-fluorouracil (ILF) versus cisplatin plus ILF (PILF) for advanced gastric cancer

4580

Background: Irinotecan, in combination with 5-fluorouracil (FU) or cisplatin, clearly demonstrated efficacy against gastric cancer. We compared the combination of irinotecan, leucovorin and FU (ILF) with cisplatin plus ILF (PILF) as first-line chemotherapy in patients with advanced gastric cancer (AGC). Methods: Patients with chemotherapy-naïve, histologically-confirmed, metastatic gastric adenocarcinoma were randomized to receive irinotecan 150 mg/m2 on day 1, leucovorin 20 mg/m2 and a 22-h infusion of FU 1,000 mg/m2 on days 1 and 2 (ILF), or ILF plus cisplatin 30 mg/m2 on day 2 (PILF). Treatment was repeated every 2 weeks until disease progression, unacceptable toxicity, or patients’ refusal. Primary endpoint was response rate which assessed every 4 cycles of chemotherapy. With a single-stage phase II design, the required number of patients was at least 35 per each arm. Results: Of 91 patients registered, 46 patients were treated with ILF and 44 with PILF. For both arms, 635 chemotherapy cycles were delivered (median, 6 for ILF and 8 for PILF; p=0.46). Both ILF and PILF were generally well tolerated. However, PILF was associated with, although statistically insignificant, substantially more grade 3 or 4 toxicities than ILF (46% and 38%, respectively). In the ILF and PILF arm, 11% and 25% of patients, respectively, discontinued treatment because of toxicity. Treatment duration was similar for both arms (4.3 for ILF v 5.6 months for PILF; p=0.13). Four patients died during treatment: one in the ILF arm and 3 in the PILF arm. The objective response rate was 37% for both arms. Disease control (response plus stable disease) was achieved in 59% and 73% (p=0.02) of patients treated with ILF and PILF. There were no significant differences in therapeutic efficacy between ILF and PILF with respect to progression-free (4.8 v 6.2 months; p=0.60) and overall (10.9 v 10.4 months; p=0.93) survival. Conclusions: Both ILF and PILF appear to be active as first-line chemotherapy for AGC, with acceptable safety profiles. Given the comparable efficacy results, ILF could be a reasonable standard chemotherapy for untreated AGC patients.

No significant financial relationships to disclose.

Comparison of the epidermal growth factor receptor gene mutation in matched primary tumor and lymph node metastasis of non-small cell lung cancer

7614

Background: Mutations in epidermal growth factor receptor (EGFR) are considered as a strong predictive marker to EGFR tyrosine kinase inhibitors (TKIs) in non-small-cell lung cancer (NSCLC). Recent studies suggested EGFR status may change between primary NSCLC and corresponding metastatic site. However, it has not fully been evaluated whether EGFR mutation differs in metastases compared to primary NSCLC. Methods: In total, 128 tumor samples from 64 NSCLC patients were investigated comparing matched 64 primary tumors, and 64 lymph node metastases. The epidermal growth factor receptor mutation status was analyzed by a direct sequencing method (exons 18–21 in EGFR) on tumor samples of primary NSCLC and corresponding lymph node metastasis. Results: In 17.2% of patents (11/64), EGFR mutation was identified in either primary NSCLC or metastasis by DNA sequencing. Six (54.5%) out of eleven cases showed discordance of EGFR mutation in the primary tumor/metastasis site. Two cases showed EGFR mutation in the metastasis but not in the primary tumor, while, in four cases, EGFR mutation was detected in the primary tumor but not in the metastasis site. The majority of discordance of EGFR mutations was identified in exon 19 (83.3%, 5/6). The median overall survival (OS) was 17.7 months (95% confidence interval, 9.4–20.0). Median OS was not varied by the discordance of EGFR mutation status between primary NSCLC and corresponding metastatic site. Conclusions: The status of EGFR mutation in primary NSCLC and that in corresponding metastasis site varied in considerable cases by DNA sequencing. Whether the status of EGFR mutation changes during the process of metastasis remains to be evaluated. Future study to evaluate the correlation of tumour response to TKIs and the discordance of the EGFR mutation status is warranted.

No significant financial relationships to disclose.

Two different schedules of docetaxel plus cisplatin as first-line therapy in advanced non-small cell lung cancer: A preliminary result from a randomized phase II study

7135

Background: There has been increasing interest in the use of a weekly administration of docetaxel as a way of reducing its hematologic toxicity. The purpose of this randomized study is to evaluate the toxicity and efficacy of docetaxel and cisplatin combination on two schedules in patients with previously untreated, advanced non-small cell lung cancer (NSCLC). Methods: Consenting patients with stage IIIB/IV or recurrent NSCLC were randomized to receive first-line chemotherapy with cisplatin 75 mg/m2 on day 1, plus either weekly (35 mg/m2 on day 1, 8, 15 of a 4-week cycle) or 3-weekly (75 mg/m2 on day 1 of a 3-week cycle) docetaxel, both for up to 6 cycles. Objectives of this randomized phase II trial were response, toxicity and quality of life (QOL; measured with EORTC QLQ-C30). With a two-stage phase II design, the required number of patients was 39 per each arm. Results: Of 85 patients accrued, 71 patients were evaluable for response and 83 for safety. Baseline characteristics were well-balanced between the two arms: male (56 patients); median age (64 years); adenocarcinoma/squamous cell carcinoma (53/32); stage IIIB/IV/recurrent (12/63/10); ECOG performance status 0/1/2 (20/44/21). Median number of chemotherapy cycles was 3 (1–6) for both arms. Median dose intensities were docetaxel 88%, cisplatin 98% in weekly arm, and docetaxel 97%, cisplatin 98% in 3-weekly arm. The objective responses of weekly and 3-weekly arm were 38% (95% CI, 23–53) and 42% (95% CI, 27–57), respectively. There was significantly more grade 3/4 neutropenia (66% v 12%; P < .001) and febrile neutropenia (40% v 7%; P < .001) on 3-weekly arm but less grade 3/4 diarrhea (2% v 14%; P = .05) and severe skin/nail toxicity (5% v 29%; P = .003). No difference in the rates of treatment delay or dose reduction for both arms; however, 19% of day 15 docetaxel were omitted in weekly arm due to toxicity. Conclusions: Both weekly and 3-weekly docetaxel plus cisplatin appear to be active as first-line chemotherapy for advanced NSCLC, with different safety profiles. Updated results and QOL data, including a prolonged follow-up, will be presented.

No significant financial relationships to disclose.

Second-line chemotherapy with mitomycin C and S-1 in patients with advanced gastric cancer

14083

Background: S-1, a fourth generation oral fluoropyrimidine that mimics infusional 5-fluorouracil, has demonstrated activity against advanced gastric cancer. Based on a single agent activity and in vitro synergy between mitomycin C (MMC) and 5-fluorouracil, we conducted a phase II study to assess the efficacy and tolerability of the combination of S-1 and MMC as second-line chemotherapy for previously treated, advanced gastric cancer. Methods: Patients with measurable gastric cancer, progressive after at least one prior chemotherapy for metastatic disease, were treated with MMC 7 mg/m2 on day 1 and S-1 40 mg/m2 twice daily as an intermittent regimen of 4 weeks of treatment followed by a 2-week rest. Treatment was repeated every 6 weeks, for up to 4 cycles. Objective response rate was the primary endpoint and was evaluated every 2 cycles of chemotherapy. With a single-stage phase II design, at least 25 patients were required. Results: Of the 26 patients registered, 24 patients were evaluable for response and 26 for safety. Eighteen patients (69%) were previously treated with 5-fluorouracil-based chemotherapy, and 10 (39%) were treated with taxanes. The patients’ median age was 55 years (range, 38–73) and 7 (27%) had an ECOG performance status of 2. A total of 64 chemotherapy cycles were delivered (median, 2; range, 1–4). In an intent-to-treat analysis, 6 patients (23%) achieved a partial response, which maintained for 3.5 months. The median progression-free and overall survivals were 4.4 months (95% CI, 1.7–7.2) and 5.4 months (95% CI, 3.4–7.4), respectively. Major toxic effects included stomatitis, diarrhea and fatigue, but were generally mild and manageable. No patient developed hemolytic reaction. Conclusions: Second-line chemotherapy with MMC and S-1 is an effective regimen for advanced gastric cancer with an acceptable toxicity profile and a convenient administration schedule.

No significant financial relationships to disclose.

The ERB family receptor dimerization in glioblastoma—An eTag assay analysis of 23 cases

1582

Background: Glioblastoma is the most malignant astrocytic tumor and accounts for about 50–60% of all astrocytic neoplasms. Despite intensive radiation and chemotherapy, less than 2% of patients survive more than 3 years. The Erb family of signaling molecules are transmembrane receptors with intrinsic kinase activity (except ErbB3) capable of modifying tyrosine residues on the receptor itself as well as on downstream signaling molecules. Under physiological conditions a variety of ligands interact and act as driving forces in the formation of homo and heterodimeric complexes between the four receptors leading to signal amplification and downstream activities. More than one third of glioblastoma cases show gene amplification of epidermal growth factor receptor (EGFR) which can be in truncated or rearranged form. The eTag assay system (Monogram) is an antibody based fluorescent assay that has the potential to assess the activation state of the EGFR signaling pathway. Methods: Twenty three cases of glioblastoma were selected for eTag analysis. There were twelve males and eleven females with ages ranging from 20–84 years. After reviewing the histology, 10 micron sections were cut from formalin fixed paraffin embedded (FFPE) tumor tissue blocks. Specific monoclonal antibodies of the Erb family bound to a fluorescent reporter (eTag) were applied to tissue sections. After binding of specific analyte, a second monoclonal antibody is added which acts as molecular scissors resulting in cleavage of “eTags”. The released eTag molecules are separated by capillary electrophoresis and measured as relative fluorescent units. Various FFPE tumor cell lines were used as controls. Results: Nineteen out of twenty three tumors (82%) showed the presence of dimers of the Erb family signaling pathway. High levels of intra and /or extracellular EGFR homodimers (HER-1-HER-1) were detected in eight samples (35%). EGFR-HER-3 dimers and EGFR-HER-2 dimers were seen at high levels in four and six samples (17% and 26% respectively). High levels of HER-2-HER3 dimers were detected in six samples (26%). Conclusion: The EGFR signaling pathway plays a substantial role in tumorigenesis of glioblastoma. Identification of receptor homo and heterodimers may be of value during treatment planning of individual patients.

No significant financial relationships to disclose.

A pilot phase II study of consolidation chemotherapy with docetaxel and cisplatin following concurrent chemoradiotherapy (CCRT) for locoregionally advanced head and neck squamous cell carcinoma (HNSCC)

5549

Background: With the improvement seen with CCRT in the management of locoregionally advanced HNSCC, distant failures have become a more relevant problem in terms of survival. As a consequence, more effective strategies including consolidation chemotherapy are warranted. The primary objective of this pilot phase II study was to assess the feasibility and efficacy of docetaxel and cisplatin consolidation following primary CCRT for HNSCC. Methods: Thirty-three patients with previously untreated, stage III/IV HNSCC participated in this study. CCRT consisted of cisplatin 100 mg/m2 on day 1, 22 and 43. Concurrent radiotherapy (70 Gy) to the primary tumor and neck was performed over a period of 7 weeks. After completion of CCRT, patients with no evidence of disease progression received an additional 4 cycles of consolidation chemotherapy with docetaxel 75 mg/m2 and cisplatin 75 mg/m2 every 3 weeks. To minimize the expected accrual into unacceptable treatment, either in terms of clinical response or toxicity, a total of 35 patients would be required in a two-stage design. Results: Baseline characteristics were: male (22), median age (60 years), ECOG performance status 0/1 (15/18), stage III/IV (10/23). Of these, 27 (81%) patients completed CCRT. After CCRT, 3 complete and 19 partial responses were recorded, giving an overall response rate of 67% (95% CI, 51–83%). Of the 19 patients who went to consolidation phase, only 4 (21%) completed all 4 cycles of docetaxel and cisplatin. Failure to consolidation chemotherapy was attributed to the following causes: toxicity (11 including 3 treatment-related deaths), disease progression (4). During consolidation chemotherapy, 13 patients (68%) had grade 3/4 neutropenia and febrile neutropenia occurred in 6 (32%). With consolidation chemotherapy, one patient with initial stable disease achieved a partial response. Median survival in all patients was 11.0 months, and 8.3 months for those treated with consolidation chemotherapy. Conclusions: The poor compliance and the high incidence of severe toxicities, including 3 treatment-related deaths, prompted no further evaluation of this consolidation chemotherapy following CCRT.

No significant financial relationships to disclose.

Vascular endothelial growth factor (VEGF) polymorphism is associated with prognosis of patients with gastric cancer

4019

Background: Recent studies demonstrated that the expression of vascular endothelial growth factor (VEGF) family had a prognostic significance in patients with gastric cancer. The present study analyzed VEGF polymorphism and its impact on prognosis in patients with gastric cancer. Methods: Five hundred three consecutive patients with surgically resected gastric adenocarcinoma at a single institution between January 2000 and December 2001 were enrolled into the study. Genomic DNA was extracted from paraffin-embedded tumor tissue and four VEGF (-460T > C, +405C > G, 936C> T, and -1154G > A) genotypes were determined using a PCR-RFLP assay. Results: The median age of patients was 60.0 years (range, 25–83 years), and 337 (67.0%) patients were male. Pathologic stages after resection were as follows: stage 0 (n=6, 1.2%), stage I (n=277, 55.1%), stage II (n=105, 20.9%), stage III (n=74, 14.7%), and stage IV (n=41, 8.2%). The estimated 5-year disease-free survival (DFS) rates according to stage were significantly different (p < 0.0001). Three VEGF polymorphisms (+405C > G, 936C, and -1154G > A > T) were not associated with survival of patients, while -460T > C polymorphism had a prognostic significance. In patients with early stage gastric cancer (stage 0 or 1, n=283), the estimated 5-year DFS and carcinoma-specific survival (CSS) for patients with homozygous genotype (CC or TT) of -460T > C were superior to those for heterozygous genotype (CT) (98.1% versus 90.3%, p=0.0047; 98.1% versus 92.5%, p=0.0284). In Cox multivariate regression, stage and VEGF -460T > C genotype were an independent prognostic factors for both DFS (p=0.007; p=0.010) and CSS (p=0.013; p=0.038). Conclusions: VEGF -460T > C polymorphism was found to be an independent prognostic marker for patients with curatively resected early stage gastric adenocarcinoma. Accordingly, VEGF -460T > C polymorphism can help to identify patients with unfavorable clinical outcome and thereby may be useful to refine therapeutic decisions in early stage gastric cancer.

No significant financial relationships to disclose.