Elasticity transition and loop formation in vibrated bead chains: a simulation of polymer chains

By measuring the distribution function of the end-to-end distance, we find that strongly shaken bead chains exhibit many properties, such as the rigid-rod-to-Gaussian chain transition, scaling, fast drop of loop formation probability in the short-chain regime, and enhancement of loop formation probability for kinked chains, of long-chain polymers. Though there is difference in local details between our chains and the worm-like chains, our results are consistent with recent calculations based on the worm-like chain model in many respects.

Pemetrexed versus gefitinib versus erlotinib in previously treated non-small cell lung cancer by retrospective analysis

e19103

Background: The standards in 2nd-line therapy with advanced non-small cell lung cancer (NSCLC) were erlotinib or pemetrexed as well as docetaxel. To evaluate the efficacies and safeties of pemetrexed, gefitinib, and erlotinib in previously treated NSCLC we analyzed the datas retrospectively. Methods: Eligible patents were 1) histologically confirmed pretreated advanced (stage IIIB or IV) NSCLC, 2) with at least one measurable lesion, 3) age over 18 years, 4) performance status (PS) 0–2, and 5) should never experience other two drugs as previous therapy. Patients of pemetrexed group received IV infusion of 500mg/m2 pemetrexed mixed with normal saline every 3 weeks with vitamin B12 and folate supplementation. Patients of gefitinib group received gefitinib 250mg PO daily and of erlotinib took erlotinib 150mg PO daily. Cycles of IV pemetrexed or taking PO drugs were continued until disease progression or unacceptable toxicity. Results: we analyzed 57 patients (pemetrexed; 20, gefitnib; 20, and erlotinib; 17). The response rates were 5.3%, 25.0%, and 12.5% (P=0.22), and the disease control rate were 5.3%, 40.0%, and 50.0% respectively (P<0.01). Median progression-free survival (PFS) of pemetrexed, gefitinib, and erlotinib were 1.7, 3.5 and 4.4 months (P<0.01) and median overall survival (OS) were 5.6, 21.8 and 21.5 months respectively (P=0.04). In subgroup analysis, patients with non-squamous carcinoma, smokers and good PS (0 or 1) showed longer PFS and OS in gefitinib and erlotinib compared with in pemetrexed. All of these agents showed mild and tolerable toxicity. Conclusions: In retrospective analysis, the patients with gefitinib or erlotinib had longer PFS and OS than pemetrexed, eventhough there was no significant difference for response rate in three group. These results have to confirm by large randomized prospective study because the sample size was small and it was not randomized.

No significant financial relationships to disclose.

Detection of human papillomavirus DNA from the breast carcinomas and the cervix: Are they correlated?

1544

Background: The association between human papillomavirus (HPV) and cervical cancer is well known. However, it remains unclear whether there is also a correlation between HPV infection and human breast cancer. The aim of this study is to investigate the hypothetic association between HPV infection and breast carcinoma through the comparison of the type of HPV infection in the breast and cervix. Methods: From April to December 2008, 106 patients who were diagnosed as breast cancer and underwent mastectomy were analyzed. Their breast tissue (tumor, normal parenchyme, and nipple-areolar complex) and cervix smear were analyzed for HPV infection with DNA chip microarray method. Results: 24 patients (23.1%) showed HPV infection in their cervix smear; high-risk type of HPV was found in 12 patients. But only six patients (5.8%) revealed the HPV infection in breast cancer; half of them were high-risk group (HPV-16, 31); the same types of HPV was found at the normal breast tissue in two patients of them. However, there were no patients with HPV infection in both breast and cervix concurrently. Conclusions: There were no positive results for HPV infection of cervix in HPV-infected breast cancer patients. Also, we cannot find that the presence of high-risk HPV in the breast might be related to the breast carcinogenesis. We concluded that HPV infection is not correlated to the carcinogenesis of breast.

No significant financial relationships to disclose.

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.

Warm ischemia time does not correlate with recipient graft function in laparoscopic donor nephrectomy

BACKGROUND

Laparoscopic donor nephrectomy (LDN) has been shown to be a safe and effective option for renal procurement. Studies comparing open nephrectomy and hand-assisted laparoscopy have emphasized decreased warm ischemia time when compared with "pure" laparoscopic retrieval. However, no data exist that define exactly what constitutes a prolonged warm ischemia time in terms of recipient graft function. The aim of this study was to use a large, single-institution experience with LDN to determine if warm ischemia time correlates with recipient graft function as measured by serum creatinine levels.

METHODS

A total of 640 LDNs were performed from March 1996 to August 2001. Warm ischemia times were prospectively collected and were defined as the time from renal artery occlusion to immersion in iced saline. Serial recipient creatinine levels were measured at 1 week and 1, 3, 6, and 12 months (when possible) from the transplant. Data were analyzed using Pearson correlation analysis at a confidence interval of 95%.

RESULTS

Mean warm ischemia time was 151 s with a standard error of 3.4 s and ranged from 35 to 720 s. Recipient creatinine mean at 1 week was 1.94 mg/dl with a standard error of 0.06 mg/dl and ranged from 0.5 to 10.5 mg/dl. Recipient creatinine mean at 1 month was 1.68 mg/dl with a standard error of 0.06 mg/dl and ranged from 0.6 to 8.5 mg/dl. Recipient creatinine mean at 3 months was 1.60 mg/dl with a standard error of 0.04 mg/dl and ranged from 0.6 to 8.8 mg/dl. Recipient creatinine mean at 6 months was 1.63 mg/dl with a standard error of 0.06 mg/dl and ranged from 0.7 to 13.5 mg/dl. Recipient creatinine mean at 12 months was 1.70 mg/dl with a standard error of 0.07 mg/dl and ranged from 0.5 to 14.5 mg/dl. No correlation was found between warm ischemia time and recipient creatinine levels at 1 week (p = 0.4737), 1 month (p = 0.9180), 3 months (p = 0.6227), 6 months (p = 0.8349), or 12 months (p = 0.2835).

CONCLUSIONS

Warm ischemia time does not correlate with recipient graft function in LDN within the range of times studied. Shorter warm ischemia time associated with open donor nephrectomy and hand-assisted LDN does not necessarily offer a measurable advantage in recipient graft function. During extraction of the kidney, expediency to minimize warm ischemia time should not supersede controlled and safe maneuvers in renal vessel division and extraction of the kidney.

Laparoscopic right donor nephrectomy: technique and comparison with left nephrectomy

BACKGROUND

Laparoscopic donor nephrectomy (LDN) preferentially involves the left kidney to optimize vessel length, but occasionally, right nephrectomy is preferred. Right LDN differs markedly in anatomic relations and the need for a fourth port. This retrospective study compares donor outcomes and graft function of right and left LDN and describes the technique.

METHODS

Consecutive patients undergoing right LDN from March 26, 1996 to December 31, 2000 were compared with those undergoing left LDN. Age, height, weight, body mass index, creatinine, creatinine clearance, operative time, warm ischemia time, analgesic requirements, serial postoperative creatinine, time to diet resumption, and hospital stay were compared. A second cohort matched for age, gender, race, and temporal left LDN also were compared with the group undergoing right LDN.

RESULTS

No significant differences were found for any of the parameters measured.

CONCLUSION

This study demonstrates that despite substantial differences in the procedures, donor outcome and graft survival are similar for right and left LDN.

Association of human herpesvirus 6 reactivation with severe cytomegalovirus-associated disease in orthotopic liver transplant recipients

To explore the possible interaction between human herpesvirus 6 (HHV-6) and cytomegalovirus (CMV) in patients who have undergone organ transplantation, stored serum samples from 139 orthotopic liver transplant recipients were tested for HHV-6 immunoglobulin (Ig) G and IgM antibodies. HHV-6 reactivation occurred in 87 patients (62.6%) and was associated with CMV disease (P=.01), severe CMV-associated disease (P=.01), older age (P=.005), and use of muromonab-CD3 (Orthoclone; Orthobiotech) as treatment for rejection (P=.02). Trends for an association between HHV-6 reactivation and invasive fungal disease (P=.12), bacteremia (P=.10), and graft loss (P=.12) were seen. In a multivariate analysis of risk factors for severe CMV-associated disease, HHV-6 reactivation (relative risk [RR], 3.5; 95% confidence interval [CI], 1.2-10.2; P=.02), CMV donor-positive-recipient-negative match (RR, 5.7; 95% CI, 2.5-13.2; P<.001), and elevated serum creatinine level (P<.0001) were independent predictors. HHV-6 reactivation is associated with severe CMV-associated disease in liver transplant recipients.

Optimal dosing of penicillin G in the third trimester of pregnancy for prophylaxis against group B Streptococcus

OBJECTIVE

We wanted to determine the optimal dose of intravenous penicillin (PCN) in the third trimester of pregnancy for the prophylaxis of group B Streptococcus.

STUDY DESIGN

Healthy women in the third trimester with a singleton pregnancy were recruited. Eligibility included no previous penicillin or cephalosporin allergy and no history of renal disease. We obtained a baseline 24-hour urine collection for total protein concentration and creatinine clearance. Two intravenous catheters were placed, and 1 million units of penicillin G (PCN G) sodium was infused through one catheter. Serial blood samples were obtained through the second catheter at 1, 5, 15, 30, 60, 90, 120, 150, 180, 210, and 240 minutes. Serum was stored at -80 degrees C until assays were performed. Reverse-phase high-performance liquid chromatography was used to determine serum concentrations.

RESULTS

Fifteen patients met the requirements for eligibility. The average 24-hour urine sample for total protein concentration was 187 mg/dL (range, 11-252), and creatinine clearance was 191 mL/min (range, 137-245). Average maximum serum concentration (C(max)) was 67 microg/mL (range, 34-132) and was reached within 5 minutes. Average serum PCN concentration was 12 microg/mL (range, 9-25) after 4 hours of urine collection.

CONCLUSION

The C(max) was 67 microg/mL (670 x minimum inhibitory concentration). One million units of intravenous PCN G exceeds MIC in the treatment of GBS. The dosing interval should be 4 hours to ensure anti-GBS activity in all patients. More frequent dosing does not increase activity. Current recommendations for GBS prophylaxis which use PCN G should be modified pending future studies of neonatal PCN concentrations.

Prospective study of zinc intake and the risk of age-related macular degeneration

PURPOSE

Zinc is found in high concentrations in the retina and is hypothesized to reduce the risk of age-related macular degeneration (AMD). Any long-term benefit associated with dietary zinc intake has not been evaluated.

METHODS

We followed 66,572 women and 37,636 men who were > or = 50 years old and had no diagnosis of AMD or cancer. Zinc intake from food, multivitamins, and supplements was assessed with a semiquantitative food-frequency questionnaire at baseline (in 1984 for women and in 1986 for men) and repeated during follow-up (twice for women, once for men).

RESULTS

During 10 years of follow-up for women and 8 years of follow-up for men, we confirmed 384 incident cases of AMD (195 cases of the early form and 189 cases of the late form) associated with a visual acuity loss of 20/30 or worse. After multivariate adjustment for potential risk factors, the pooled relative risk was 1.13 (95% confidence interval [CI], 0.82 to 1.57; p-value, test for trend, 0.74) among participants in the highest quintile of total zinc intake (energy-adjusted median; 25.5 mg/day for women and 40.1 mg/day for men) compared with those in the lowest quintile (energy-adjusted median; 8.5 mg/day for women and 9.9 mg/day for men). The relative risk for highest compared with lowest quintile was 1.04 (95% CI, 0.59 to 1.83; p-value, test for trend, 0.54) for zinc intake from food. Subjects who took zinc supplements had a pooled multivariate relative risk of 1.04 (95% CI, 0.75 to 1.45).

CONCLUSIONS

In these two large prospective studies, moderate zinc intake, either in food or in supplements, was not associated with a reduced risk of AMD.

Identification and role of thiols in Toxoplasma gondii egress

The nucleoside triphosphate hydrolase of Toxoplasma gondii is a potent apyrase that is secreted into the parasitophorous vacuole where it appears to be essentially inactive in an oxidized form. Recent evidence shows that nucleoside triphosphate hydrolase can be activated by dithiothreitol in vivo. On reduction of the enzyme, there is a rapid depletion of host cell ATP. Previous results also demonstrate a dithiothreitol induced egress of parasites from the host cell with a concurrent Ca2+ flux, postulated to be a consequence of the release of ATP-dependent Ca2+ stores within the tubulovesicular network of the parasitophorous vacuole. Reduction of the nucleoside triphosphate hydrolase appears crucial for its activation; however, the exact mechanism of reduction/activation has not been determined. Using a variety of techniques, we show here that glutathione promoters activate a Ca2+ flux and decrease ATP levels in infected human fibroblasts. We further show the in vitro activation of nucleoside triphosphate hydrolase by endogenous reducing agents, one of which we postulate might be secreted into the PV by T. gondii. Our findings suggest that the reduction of the parasite nucleoside triphosphate hydrolase, and ultimately parasite egress, is under the control of the parasites themselves.

Are concerns over right laparoscopic donor nephrectomy unwarranted?

OBJECTIVE

To examine the ability of several large, experienced transplantation centers to perform right-sided laparoscopic donor nephrectomy safely with equivalent long-term renal allograft function.

SUMMARY BACKGROUND DATA

Early reports noted a higher incidence of renal vein thrombosis and eventual graft loss. However, exclusion of right-sided donors would deprive a significant proportion of donors a laparoscopically harvested graft.

METHODS

A retrospective review was performed among 97 patients from seven centers performing right-sided laparoscopic donor nephrectomy. Surgical and postoperative demographic factors were evaluated. Complications were identified and long-term renal allograft function was compared with historical left-sided laparoscopic donor nephrectomy cohorts.

RESULTS

Right laparoscopic donor nephrectomy was performed for varying reasons, including multiple left renal arteries or veins, smaller right kidney, or cystic right renal mass. Mean surgical time was 235.0 +/- 66.7 minutes, with a mean blood loss of 139 +/- 165.8 mL. Conversion was required in three patients secondary to bleeding or anatomical anomalies. Mean warm ischemic time was limited at 238 +/- 112 seconds. Return to diet was achieved on average after 7.5 +/- 2.3 hours, with mean discharge at 54.6 +/- 22.8 hours. Two grafts were lost during the early experience of these centers to renal vein thrombosis. Both surgical and postoperative complications were limited, with few long-term adverse effects. Mean serum creatinine levels were higher than open and left laparoscopic donor nephrectomy on postoperative day 1, but at all remaining intervals the right laparoscopic donors had equivalent creatinine values.

CONCLUSIONS

These results confirm that right laparoscopic donor nephrectomy provides similar patient benefits, including early return to diet and discharge. Long-term creatinine values were no higher than in traditional open donor or left laparoscopic donor cohorts. These results establish that early concerns about high thrombosis rates are not supported by a multiinstitutional review of laparoscopic right donor nephrectomies.

Prospective study of dietary fat and the risk of age-related macular degeneration

BACKGROUND

The relation between intakes of total fat and specific types of fat and age-related macular degeneration (AMD) remains unclear.

OBJECTIVE

Our objective was to examine prospectively the association between fat intake and AMD.

DESIGN

We conducted a prospective follow-up study of participants in the Nurses' Health Study and the Health Professionals Follow-up Study. At baseline (1984 for women and 1986 for men), the study included 42743 women and 29746 men aged > or = 50 y with no diagnosis of AMD who were followed until 1996. Fat intake was assessed with a food-frequency questionnaire.

RESULTS

We accrued 567 patients with AMD with a visual loss of 20/30 or worse. The pooled multivariate relative risk (RR) for the highest compared with the lowest quintile of total fat intake was 1.54 (95% CI: 1.17, 2.01; P for trend = 0.008). Linolenic acid was positively associated with risk of AMD (top versus bottom quintile of RR: 1.49; 95% CI: 1.15, 1.94; P for trend = 0.0009). Docosahexaenoic acid had a modest inverse relation with AMD (top versus bottom quintile of RR: 0.70; 95% CI: 0.52, 0.93; P for trend = 0.05), and >4 servings of fish/wk was associated with a 35% lower risk of AMD compared with < or = 3 servings/mo (RR: 0.65; 95% CI: 0.46, 0.91; P for trend = 0.009).

CONCLUSIONS

Total fat intake was positively associated with risk of AMD, which may have been due to intakes of individual fatty acids, such as linolenic acid, rather than to total fat intakes per se. A high intake of fish may reduce the risk of AMD.

Urinary retention following routine neurosurgical spine procedures

BACKGROUND

The rate and duration of urinary retention after routine cervical and lumbar spine procedures were studied.

METHODS

Preoperative, intraoperative, and postoperative factors related to urinary retention (age, sex, duration of operation, medications, Foley use, hospital stay, and cost) were analyzed in a retrospective review of 503 patients' charts.

RESULTS

Urinary retention occurred 38% of the time following cervical and lumbar spine procedures. Advanced age and preoperative beta blockers contributed to a higher incidence of urinary retention. Preoperative anti-inflammatory medications and narcotic analgesics reduced the frequency of urinary retention. The duration of urinary retention was prolonged in older patients and patients who underwent intraoperative Foley catheterization. Urinary retention contributed to longer hospitalization and increased hospital costs.

CONCLUSIONS

Transient urinary retention is a common complication of routine neurosurgical spine procedures that prolongs hospital stays and increases the costs of hospitalization.

Maternal and prepubertal diet, mammary development and breast cancer risk

At present, we do not know what causes sporadic breast cancer. Environmental factors,particularly diet, appear to explain at least 70% of newly diagnosed breast cancers, but it is not clear what these factors are. We propose that the lack of progress in this area is due to a lack of considering the effect of timing of environmental and dietary exposures on the breast. The evidence provided above suggests that an in utero exposure to an estrogenic environment-including that caused by diet [high (n-6) PUFA or genistein]-increases breast cancer risk. This increase may be mediated by an increased presence of TEB in the mammary epithelial tree and increased ER-alpha levels, reduced ER-beta levels or both. Prepubertal estrogenic exposure, in contrast, reduces later risk of developing breast cancer. The protective effect of estrogens may be mediated by early epithelial differentiation, reduced presence of ER-alpha and increased levels of ER-beta in the mammary gland. The challenge we are now facing is to determine whether the data obtained mainly through the use of animal models is relevant to women and if so, how we might be able to modulate pregnancy and childhood estrogenic exposure by appropriate dietary modifications to reduce breast cancer risk in women.

Laparoscopic nephrectomy in the markedly obese living renal donor

OBJECTIVES

To determine whether laparoscopic living donor nephrectomy is safe and efficacious in markedly obese renal donors.

METHODS

From 1996 to 1999, 431 laparoscopic living donor nephrectomies were performed. The markedly obese group consisted of 41 patients with a body mass index (BMI) greater than 35. Forty-one controls with a BMI less than 30 were matched to the obese donors by sex, age, race, and date of surgery.

RESULTS

The markedly obese and control groups were closely matched in sex, race, age, serum creatinine level, creatinine clearance, HLA match to recipient, side of donated kidney, and experience level of the surgeons. The obese patients had a BMI range of 35.2 to 53.9 (mean 39.3), and the control patients had a BMI range of 18.4 to 29.0 (mean 24.3). Donor operations in the markedly obese were significantly longer by an average of 40 minutes. The greater intraoperative blood loss and longer extraction incision length seen in the markedly obese did not reach statistical significance. More and larger laparoscopic ports were used in the markedly obese. Obese donors were more likely to require conversion from laparoscopic nephrectomy to open nephrectomy than ideal-sized donors. The postoperative recovery of the gastrointestinal tract, hospitalization time, analgesic requirements, and total complications were equal in the two groups, although the obese donors' complications tended to be cardiopulmonary problems. The recipient graft function was equivalent between the two groups.

CONCLUSIONS

Laparoscopic living donor nephrectomy is more difficult to perform in the markedly obese but is associated with an equivalent donor morbidity and recipient renal outcome.

Laparoscopic live donor nephrectomy: the University of Maryland 3-year experience

PURPOSE

We determined whether laparoscopic living donor nephrectomy decreases the morbidity of renal donation for the donor, while providing a renal allograft of a quality comparable to that of open donor nephrectomy.

MATERIALS AND METHODS

In a 3-year period laparoscopic donor nephrectomy was performed via the transperitoneal approach. We evaluated donor and recipient medical records for preoperative donor characteristics, intraoperative parameters and complications, and postoperative recovery and complications.

RESULTS

Of the 320 laparoscopic donor nephrectomies performed the left kidney was removed in 97.5%. Intraoperative complications, which developed in 10.4% of cases, tended to occur early in the experience and required conversion to open nephrectomy in 5. Average operative time was 31/2 hours and warm ischemia time was 21/2 minutes. As the series progressed, blood loss as well as laparoscopic port size and number decreased but extraction site size remained constant at 7 cm. Urinary retention, prolonged ileus, thigh numbness and incisional hernia were the most common postoperative complications. Postoperative analgesic requirements were low and average hospitalization was 66 hours.

CONCLUSIONS

Laparoscopic donor nephrectomy appears to be safe and decreases morbidity in the renal donor. Allograft function is comparable to that in open nephrectomy series. The availability of laparoscopic harvesting may be increasing the living donor volunteer pool.

Simultaneous cadaver pancreas living-donor kidney transplantation: a new approach for the type 1 diabetic uremic patient

OBJECTIVE

To review the authors' experience with a new approach for type I diabetic uremic patients: simultaneous cadaver-donor pancreas and living-donor kidney transplant (SPLK).

SUMMARY BACKGROUND DATA

Simultaneous cadaver kidney and pancreas transplantation (SPK) and living-donor kidney transplantation alone followed by a solitary cadaver-donor pancreas transplant (PAK) have been the transplant options for type I diabetic uremic patients. SPK pancreas graft survival has historically exceeded that of solitary pancreas transplantation. Recent improvement in solitary pancreas transplant survival rates has narrowed the advantage seen with SPK. PAK, however, requires sequential transplant operations. In contrast to PAK and SPK, SPLK is a single operation that offers the potential benefits of living kidney donation: shorter waiting time, expansion of the organ donor pool, and improved short-term and long-term renal graft function.

METHODS

Between May 1998 and September 1999, the authors performed 30 SPLK procedures, coordinating the cadaver pancreas transplant with simultaneous transplantation of a laparoscopically removed living-donor kidney. Of the 30 SPLKs, 28 (93%) were portally and enterically drained. During the same period, the authors also performed 19 primary SPK and 17 primary PAK transplants.

RESULTS

One-year pancreas, kidney, and patient survival rates were 88%, 95%, and 95% for SPLK recipients. One-year pancreas graft survival rates in SPK and PAK recipients were 84% and 71%. Of 30 SPLK transplants, 29 (97%) had immediate renal graft function, whereas 79% of SPK kidneys had immediate function. Reoperative rates, early readmission to the hospital, and initial length of stay were similar between SPLK and SPK recipients. SPLK recipients had a shorter wait time for transplantation.

CONCLUSIONS

Early pancreas, kidney, and patient survival rates after SPLK are similar to those for SPK. Waiting time was significantly shortened. SPLK recipients had lower rates of delayed renal graft function than SPK recipients. Combining cadaver pancreas transplantation with living-donor kidney transplantation does not harm renal graft outcome. Given the advantages of living-donor kidney transplant, SPLK should be considered for all uremic type I diabetic patients with living donors.

The AGAMOUS-LIKE 20 MADS domain protein integrates floral inductive pathways in Arabidopsis

The very late-flowering behavior of Arabidopsis winter-annual ecotypes is conferred mainly by two genes, FRIGIDA (FRI) and FLOWERING LOCUS C (FLC). A MADS-domain gene, AGAMOUS-LIKE 20 (AGL20), was identified as a dominant FRI suppressor in activation tagging mutagenesis. Overexpression of AGL20 suppresses not only the late flowering of plants that have functional FRI and FLC alleles but also the delayed phase transitions during the vegetative stages of plant development. Interestingly, AGL20 expression is positively regulated not only by the redundant vernalization and autonomous pathways of flowering but also by the photoperiod pathway. Our results indicate that AGL20 is an important integrator of three pathways controlling flowering in Arabidopsis.

Relative contribution of preload and afterload to the reduction in cardiac output caused by nitric oxide synthase inhibition with L-N(G)-methylarginine hydrochloride 546C88

OBJECTIVE

The nitric oxide synthase inhibitor L-N(G)-methylarginine hydrochloride (L-NMMA HC1 546C88) causes reductions in cardiac output (CO), a potential limitation to clinical application. This drop in CO exceeds that from phenylephrine at matched systemic arterial pressure. We tested the hypothesis that the greater fall in CO attributable to L-NMMA primarily reflects a difference in venoconstriction between agents, such that phenylephrine produces larger increases in preload (an independent determinant of CO).

DESIGN

Random infusion of phenylephrine or L-NMMA.

SETTING

An animal research laboratory.

SUBJECTS

Eight healthy, conscious, male dogs.

INTERVENTIONS

L-N(G)-methylarginine hydrochloride (20 mg/kg for 1 hr) and phenylephrine (0.5 to 3 microg/kg/min) were administered into eight dogs chronically instrumented to measure left ventricular pressure and dimension. Data were measured at a constant heart rate (140 beats/min) to render CO proportional to stroke dimension.

MEASUREMENTS AND MAIN RESULTS

At a matched increase in afterload (effective arterial elastance), L-NMMA increased preload (end-diastolic dimension) to a lesser degree (3.8%+/-1.5%, p < .05) than phenylephrine (9.6%+/-1.6%, p < .05 vs. L-NMMA). Neither L-NMMA nor phenylephrine affected the slope of the end-systolic pressure dimension relationship, although L-NMMA shifted the relationship rightward (1.7+/-0.7 mm, p < .05), consistent with a mild negative inotropic effect. L-NMMA decreased the stroke dimension to a greater extent than phenylephrine (-24.1%+/-6.8% and -10.6%+/-3.4%, respectively, p < .05).

CONCLUSIONS

Differential CO responses to phenylephrine and L-NMMA were primarily attributable to changes in preload. Variable venular vs. arteriolar constrictor effects must be considered when evaluating the integrated cardiovascular response to a vasoactive agent.