Phase II study of everolimus in patients with advanced gastric cancer refractory to chemotherapy including fluoropyrimidine and platinum

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Background: To evaluate feasibility with activity and toxicities of everolimus, a novel inhibitor of mammalian target of rapamycin (mTOR), in patients with advanced gastric cancer (AGC) who failed chemotherapy including both fluoropyrimidine and platinum (FP).

Methods: Fifty-four patients were enrolled between Jul 2008 and Feb 2010. Everolimus, 10 mg daily, was given until disease progression or unacceptable toxicity. Primary objective was to determine 4-month progression-free survival (PFS) and secondary objectives were to investigate response rate, toxicity and overall survival OS rate. Pre- (n = 28) and on-treatment (n = 19) tumor biopsies were evaluated for phosphorylated (p) mTOR, pS6 kinase1, pS6 and eukaryotic initiation factor 4E binding protein 1 expression.

Results: A total of 180 cycles of everolimus were administered with a median of 2 (range, 1-20) cycles in each patient. Two patients (3.7%) achieved confirmed partial response and 19 patients (35.2%) showed stable disease, resulting in a disease control rate of 38.9%. At a median follow-up duration of 8.7 months in surviving patients (range, 3.0–19.4 months), a 4-month PFS rate was 18.4% with a median PFS of 1.7 months (95% CI, 1.5-2.2 months) and a median OS time was 8.3 months (95% CI, 4.5-12.1 months). Peritoneal metastasis (Hazard ratio [HR], 3.97; 95% CI, 1.54-10.23; p = 0.010) and low expression level of pS6Ser240/4 at baseline (HR, 7.64; 95% CI, 2.591-22.51; p = 0.001) were significantly associated with shorter PFS time. Treatment was in general well tolerated. Toxicities of grade 3/4 included anemia (9.4%), thrombocytopenia (9.4%), hepatic dysfunction (11.3%) and pulmonary toxicities (one interstitial pneumonitis and a diffuse alveolar hemorrhage [DAH] case). The DAH and cardiopulmonary dysfunction in another case resulted in treatment-related mortalities.

Conclusions: Everolimus monotherapy showed modest activity against AGC refractory to FP. pS6Ser240/4 might be a potential biomarker for the clinical activity of everolimus. The toxicity profile was generally mild. However, careful monitoring for treatment-related pulmonary complication seems to be required.

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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.

Changes in imatinib plasma trough level during long-term treatment of patients with advanced gastrointestinal stromal tumors

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Background: Pharmacokinetic study in patients with gastrointestinal stromal tumors (GISTs) suggested that plasma concentrations of imatinib decrease following long-term exposure. We therefore measured changes in imatinib plasma trough levels (Cmin) after long-term exposure.

Methods: Between November 2009 and May 2010, follow-up (FU) imatinib Cmin was measured in 65 patients who received the same dose of imatinib for at least 9 months after a previous baseline (BL) measurement. Total 244 blood samples were obtained (127 at BL and 117 at FU) and plasma level was measured by liquid chromatography-tandem mass spectrometry.

Results: Median patient age was 54 years (range, 28–76 years) and 42 (64.6%) patients were male. Sixty-one (93.8%) patients were treated with 400 mg/day imatinib and 4 (6.2%) with 300 mg/day. The median interval from initiation of imatinib to BL test was 6.4 months (range, 0.5–66.6 months), and the median interval between BL and FU test was 13.1 months (range, 9.6–18.4 months). The mean ± standard deviation imatinib Cmin was significantly higher at FU than at BL (1442 ± 693 ng/mL vs 1221 ± 624 ng/mL, p<0.001). The mean inter- and intra-subject variabilities were 49.2% and 25.5%, respectively, at BL, and 44.2% and 20.4%, respectively, at FU. Multivariate analysis showed a significant correlation between the ratio of FU to BL imatinib Cmin and that of albumin (r=-0.397, p=0.001). In per-sample analysis, imatinib Cmin was significantly correlated with age, hemoglobin, albumin, creatinine clearance, previous major gastrectomy and time between initiation of imatinib and plasma level tests.

Conclusions: Steady-state imatinib Cmin did not decrease but remained stable in most GIST patients during long-term treatment. Changes in imatinib Cmin were associated with changes in albumin concentration. Monitoring of imatinib Cmin only for concerns about time-dependent decreases in imatinib exposure is not necessary.

[Table: see text]

Major arterial aneurysms and pseudoaneurysms in Behçet's disease: results from a single centre

OBJECTIVE

Behçet's disease (BD) with arterial involvement is closely correlated with mortality and morbidity due to life-threatening complications such as arterial occlusion and aneurysm rupture. We aimed to determine the clinical characteristics of BD patients with aneurysms and pseudoaneurysms in the major arterial systems.

METHODS

Medical records of 30 BD patients diagnosed with aneurysms or pseudoaneurysms in the major arterial systems were reviewed to determine the clinical characteristics of BD, the sites and types of arterial aneurysms or pseudoaneurysms, laboratory test results, and response to treatment.

RESULTS

A total of 47 aneurysms and pseudoaneurysms (32 saccular aneurysms, eight fusiform aneurysms, and seven pseudoaneurysms) were detected in 30 patients. Most aneurysms and pseudoaneurysms (27 patients, 90%) had not ruptured. Symptomatic lesions presented in 21 patients (70%), and asymptomatic lesions were incidentally detected in nine (30%). Ten of the 30 patients (33.3%) presented two or more aneurysmal lesions. Recurrence was observed in five patients (16.7%) after treatment with stent graft (n = 3), graft interposition (n = 1), or graft embolization (n = 1).

CONCLUSION

We suggest that BD patients diagnosed with major arterial aneurysms should be further evaluated to detect possible associated venous or arterial thrombosis formations or aneurysmal lesions at other sites.

Unusual pathology of canary poxvirus infection associated with high mortality in young and adult breeder canaries (Serinus canaria)

Mortality in excess of 65% occurred in a flock of 450 canaries (Serinus canaria). Clinical signs in the canaries included severe respiratory distress, loss of feathers and/or scaly skin on the head, neck and back, anorexia, loss of weight and fluffed-up appearance of several days duration before death. Gross pathology in most of the canaries included thickened eye lids and small scab-like nodules on the skin of the head and neck, enlarged thymus, mild to severe consolidation of lungs and exudate in the sinuses and trachea. A few birds also had thickened air sacs and enlarged and pale spleens. Microscopically unusual lesions included severe epithelial proliferation and hypertrophy and mononuclear inflammatory cells containing eosinophilic intracytoplasmic inclusion bodies of poxvirus in the thymus, bursa of Fabricius, spleen, bone marrow, air sac, peritoneum, external and middle ears, and lachrymal gland. Similar inclusion bodies associated with inflammation were also seen in the epidermis, dermis, feather follicles, conjunctivae, sinuses, turbinates, choana, oral mucosa including tongue, oesophagus, larynx, trachea, syrinx and bronchi and parabronchi of lungs. Some of the birds also had concurrent bacterial, mycotic and polyomavirus infections. Poxvirus was isolated from lungs and skin in chicken embryo liver cells and confirmed as avian poxvirus by polymerase chain reaction.

Self-assembled growth and luminescence of crystalline Si/SiOx core-shell nanowires

Crystalline Si/SiOx core/shell nanowires (NWs) are self-assembled by annealing Ni-coated hydrogenated Si-rich SiOx (SRO:H) films at 1100 degrees C in the presence of Si powder. Plasma-enhanced chemical vapor deposition is used to grow 100 nm SRO:H thin films with varying silicon concentration (n(Si)). The NWs vary from SiOx nanowires to Si/SiOx core/shell structures depending on the composition of the SRO:H substrate, with the fraction of core/shell structures increasing with increasing Si concentration. As n(Si) increases from 37 to 43 at.%, the average diameter of the NWs also increases from 48 to 157 nm. A growth model based on the diffusion-assisted vapor-liquid-solid mechanism is proposed to explain how the core/shell structures are self-assembled. Photoluminescence (PL) spectra of the individual NWs have two major emission bands in the near UV (381 nm) and blue (423 nm) ranges at n(Si) = 43 at.%, named as UV and BL PL bands, respectively. In contrast, only the BL PL band is observed at n(Si) < or = 39 at.%. These results suggest that the BL and UV PL bands can be attributed to the defect states in the SiOx shell and at the Si core/SiOx shell interface, respectively, and that the BL band is closely related to the growth process of the NWs.