Neoadjuvant chemoradiotherapy with concurrent cisplatin/5-fluorouracil is associated with increased pathologic complete response and improved survival compared to carboplatin/paclitaxel in patients with locally advanced esophageal cancer

Trimodal therapy consisting of neoadjuvant chemoradiation followed by esophagectomy has become the standard of care in North America for locally advanced esophageal cancer. While cisplatin/5-fluorouracil has been a common concurrent chemotherapy regimen since the 1980s, its utilization has declined in recent years as the Chemoradiotherapy for Oesophageal Cancer Followed by Surgery Study (CROSS) trial regimen of carboplatin/paclitaxel has become widely adopted. The efficacy of the CROSS regimen compared to alternate chemotherapy choices, however, has rarely been evaluated when each is used as a component of a trimodal treatment approach. The aim of this study is to report our institutional experience with these two concurrent chemotherapy regimens at a specialized esophageal cancer center.We performed an Institutional Review Board-approved retrospective review of a prospectively maintained institutional foregut registry from a single National Cancer Institute-designated cancer center. Esophageal cancer patients who completed trimodal therapy with a chemotherapy regimen of either carboplatin/paclitaxel or cisplatin/5-fluorouracil were identified and divided into groups based on their chemotherapy regimens. Multivariable logistic regression was used to analyze pathologic complete response rates, while the Kaplan-Meier and Cox proportional hazards models were utilized to evaluate recurrence-free and overall survival. Analytical models were adjusted for age, clinical stage, radiation dose, histologic subtype (adenocarcinoma vs. squamous cell carcinoma), and time interval from completion of neoadjuvant therapy to surgery.One hundred and forty-two patients treated between January of 2000 and July of 2015 were identified as meeting inclusion criteria. Of this group, 87 had received the CROSS regimen of carboplatin/paclitaxel, while 55 had completed cisplatin/5-fluorouracil. Multivariable analysis demonstrated that the cisplatin/5-fluorouracil.group had an increased odds of pathologic complete response (odds ratio = 2.68, 95% confidence interval, P = 0.032), as well as significantly improved recurrence-free survival (hazard ratio = 0.39, 95% confidence interval 0.21-0.73, P = 0.003) and overall survival (hazard ratio = 0.46, 95% confidence interval 0.24-0.87, P = 0.016), compared to the carboplatin/paclitaxel group.Concurrent chemotherapy with cisplatin/5-fluorouracil in locally advanced esophageal cancer is associated with higher rates of pathologic complete response and improved recurrence-free and overall survival compared to the CROSS regimen of carboplatin/paclitaxel. This suggests that, for select patients, alternate neoadjuvant chemotherapy approaches, such as cisplatin/5-fluorouracil, merit reconsideration as potential primary treatment choices in the management of this highly morbid disease.

Preoperative carboplatin and paclitaxel-based chemoradiotherapy for esophageal carcinoma: results of a modified CROSS regimen utilizing radiation doses greater than 41.4 Gy

Trimodality therapy for resectable esophageal and gastroesophageal junction cancers utilizing preoperative radiotherapy with concurrent carboplatin and paclitaxel-based chemotherapy is being increasingly utilized secondary to the results of the phase III CROSS trial. However, there is a paucity of reports of this regimen as a component of chemoradiotherapy in North America. We aim to report on our clinical experience using a modified CROSS regimen with higher radiotherapy doses. Patients with advanced (cT2-cT4 or node positive) esophageal or gastroesophageal junction carcinoma who received preoperative carboplatin/paclitaxel-based chemoradiotherapy with radiation doses of greater than 41.4 Gray (Gy) followed by esophagectomy were identified from an institutional database. Patient, imaging, treatment, and tumor response characteristics were analyzed. Twenty-four patients were analyzed. All but one tumor had adenocarcinoma histology. The median radiation dose was 50.4 Gy. Pathologic complete response was achieved in 29% of patients, with all receiving 50.4 Gy. Three early postoperative deaths were seen, due in part to acute respiratory distress syndrome and all three patients received 50-50.4 Gy. With a median follow-up of 9.4 months (23 days-2 years), median survival was 24 months. Trimodality therapy utilizing concurrent carboplatin/paclitaxel with North American radiotherapy doses appeared to have similar pathologic complete response rates compared with the CROSS trial, but may be associated with higher toxicity. Although the sample size is small and further follow-up is necessary, radiation doses greater than 41.4 Gy may not be warranted secondary to a potentially increased risk of severe radiation-induced acute lung injury.

Quality-of-life measurements in patients receiving radiation therapy for colorectal malignancies as compared to other gastrointestinal malignancies

587

Background: Therapy for GI malignancies has long been known to have a marked impact on quality of life, yet this relationship remains poorly understood.

Methods: A retrospective, IRB-approved chart review was performed of 722 patients receiving RT for any cancer diagnosis between 1/1/2006 and 12/31/2008. Subjects completed the Functional Assessment of Cancer Therapy General (FACT-G) questionnaire before and after RT. Pre- and immediately post-RT course scores were compared using student t-tests with Bonferroni correction for multiple comparisons (5 comparisons, alpha =.01).

Results: 722 of 1369 (52.7%) possible patients participated in the database. Complete pre and post RT spirituality data were available for 73 (64.6%) patients with GI malignancies. Average age was 62 years, 58 (79%) were male and 52 (71%) received definitive treatment. 27 (37%) had esophageal or gastric cancer, 22 (30%) had colorectal cancer and 24 (33%) had other GI malignancies such as pancreatic or hepatobiliary. Colorectal cancer patients fared better in overall QOL as compared to esophageal and gastric patients, pancreatic and hepatobiliary patients and patients with GI malignancies as a whole, and were the only group in which decline in overall QOL as measured by the FACT-G (77.22 to 73.08, p=0.216) did not reach or approach significance. This appeared to be largely driven by differences in physical and especially functional well-being, in which colorectal patients demonstrated the smallest decline (16.14 to 15.59, p=0.466) of any group. Colorectal patients did, however, demonstrate a larger decline in physical well-being (22.35 to 18.05, p=0.010) and overall QOL than did all-comers with any primary malignancy (22.1 to 19.4, p<.001) and (81.3 to 78.9, p<.001) respectively.

Conclusions: Physical and functional well-being, as well as overall quality of life are known to decline in patients with GI malignancies. Patients with colorectal disease appear to fare better than those with esophageal, stomach, pancreatic or hepatobiliary malignancies by these measures. Additional investigations are warranted to further define these differences.

No significant financial relationships to disclose.

Long-term update of U.S. GI Intergroup RTOG 98-11 phase III trial for anal carcinoma: Comparison of concurrent chemoradiation with 5FU-mitomycin versus 5FU-cisplatin for disease-free and overall survival

367

Background: On initial publication of GI Intergroup RTOG 98-11, concurrent chemoradiation with 5FU+mitomycin (MMC) decreased colostomy failure (CF) vs induction plus concurrent 5FU+cisplatin (CDDP), but did not significantly impact disease free or overall survival (DFS, OS). The intent of the current analysis is to determine the long-term impact of treatment on survival (DFS, OS, colostomy-free [CFS]), CF and relapse (local-regional [LRF], distant [DM]) in this patient group.

Methods: Stratification factors included gender, clinical node status, and primary size. DFS/OS were estimated univariately by Kaplan-Meier method and treatment arms compared by log-rank test. Time to relapse/CF were estimated by cumulative incidence method and treatment arms compared by Gray's test. Multivariate analyses were done with Cox proportional hazard models to test for treatment differences, adjusting for stratification factors.

Results: Of 682 patients accrued, 649 were analyzable for outcomes. As seen in the table, 5-yr DFS and OS were statistically better for RT+5FU/MMC vs RT+5FU/CDDP (67.7 v 57.6%, p=.0.0045; 78.2 v 70.5%, p=0.021) with trends toward statistical significance for CFS, LRF, and CF (71.8 v 64.9%, p=0.053; 20 v 26.5%, 11.9 v 17.3%, p=0.092 and 0.075). Similar results were seen in multivariate analysis.

Conclusions: Concurrent chemoradiation with 5FU-MMC has a statistically significant impact on DFS and OS vs induction + concurrent 5FU-CDDP and borderline significance for CFS, CF and LRF. Therefore, RT+5FU/MMC remains the preferred standard of care. Potential strategies to improve outcomes include treatment intensification and individualized molecular-based treatment. Supported by RTOG grant U10 CA21661 and CCOP grant U10 CA37422 from the National Cancer Institute (NCI).

[Table: see text]

No significant financial relationships to disclose.

Association of excision repair cross-complementation group 1 (ERCC1) gene expression (GE) with outcome in stage II-III esophageal adenocarcinoma (EA) patients treated with preoperative platinum-based chemoradiation (CRT) in a phase II cooperative study (SWOG 0356)

2

Background: Preoperative platinum-based CRT for operable esophageal cancer has improved overall survival (OS) compared to surgery alone. The phase II SWOG 0356 trial designed to test oxaliplatin (OXP) plus infusion 5-fluorouracil (5-FU) and external beam radiation prior to surgery for potentially curable EA has produced promising centrally confirmed complete pathologic response (pCR) rate (28.3%). After surgery patients were given a second cycle of OXP and 5FU. 2-year OS was 54.2%. However, treatment efficacy may be significantly compromised as a result of interindividual variations. We tested whether intratumoral GE levels in drug metabolism (DPD, GSTPi, TS and TP) and DNA repair (ERCC1 and XPD) predicted clinical outcome (CO). We also tested whether specific pattern of 12 polymorphisms in 8 genes (drug metabolism (GSTP, MTHFR and TS) and DNA repair (ERCC1, RAD51, XPD, XRCC1 and XRCC3)) predicted CO.

Methods: A total of 90 patients from the SWOG 0356 study were eligible for the molecular correlative study. mRNA was extracted from laser-capture-microdissected tumor tissue. After cDNA was prepared by reverse transcription, quantitation of the candidate genes and an internal reference gene (ß-actin) was performed using a fluorescence-based real-time detection method (TaqMan). Established GE cutoffs were tested (ERCC1 <1.7 x 10-3; TS <4.0 x 10-3). DNA was extracted from blood and genotyped using PCR-RFLP techniques.

Results: In univariate analysis, we found ERCC1 GE levels to be significantly associated with progression-free survival (PFS) and OS. Patients with high ERCC1 GE levels had worse 2-year PFS (17 vs 67%, p=0.004) and 2-year OS (37 vs 72%, p=0.04) compared to low GE levels. ERCC1 GE levels were not associated with pCR. All the other GE levels tested did not show significant association with CO. None of the tested polymorphisms showed any association with CO.

Conclusions: Our data suggest that GE levels of ERCC1 may help to identify patients with stage II-III EA likely to experience longer survival when treated with preoperative OXP-based CRT.

No significant financial relationships to disclose.

Patterns of radiotherapy practice in the management of gastric cancer: Preliminary findings from the Quality Research in Radiation Oncology (QRRO) GI Committee process surveys

77

Background: The specific aim of the ACR QRRO survey was to determine the national patterns of radiotherapy (RT) practice in patients (pts) treated for stage IB–IV (non-metastatic) gastric cancer (GC).

Methods: A National Process Survey was conducted from randomly selected U.S. RT facilities to assess demographics, staging, geographic region, practice setting, and treatment through retrospective on-site record review of eligible GC cases treated from 2005-2007. Three clinical performance measures (CPMs): 1) use of CT-based treatment planning; 2) use of dose volume histograms (DVHs) to evaluate RT dose to the kidneys and liver; 3) completion of RT within the prescribed time frame were assessed. Three emerging quality indicators: 1) use of intensity modulated RT (IMRT); 2) use of image-guided tools (IGRT), other than CT, for RT target delineation; 3) use of preop RT were also assessed.

Results: CPMs were computed on data collected through Aug, 2010 for 250 eligible pts at 45 institutions. Median age was 62 years; 66% male; 60% Caucasian. 13% were AJCC 2002 stage I, 29% II, 32% IIIA, 10% IIIB and 12% IV. Most pts (43%) were treated at academic centers with 32% at large non-academic centers and 25% medium-small facilities. Almost all (99.5%) pts underwent CT-based planning and 75% had DVHs to evaluate normal tissue doses to the kidneys and liver. 70% completed RT within the prescribed time frame. IMRT and IGRT were used in 22% and 17% of pts, respectively. IGRT techniques included: PET (n = 20), MRI (n = 1), respiratory gating and/or 4D-CT (n = 22) and on-board imaging (n = 10). 19% of pts received preop RT.

Conclusions: Preliminary findings from QRRO's analysis of radiation practice patterns for non-metastatic gastric cancer indicate widespread adoption of CT-based planning with the use of DVHs to evaluate normal tissue doses. Moreover, most pts completed adjuvant RT in the prescribed time frame. Emerging RT techniques such as IMRT and IGRT were not routinely incorporated into clinical practice during the evaluated time period. These data will serve as a benchmark for future QRRO gastric cancer surveys.

No significant financial relationships to disclose.

Emotional well-being and quality of life in patients undergoing radiation therapy for pancreatic and hepatobiliary malignancies

297

Background: Therapy for GI malignancies has long been known to have a marked impact on quality of life, yet this relationship remains poorly understood. The specific aim of this analysis was to evaluate the impact of radiation therapy (RT) on emotional well-being and QOL in patients receiving RT for pancreatic and hepatobiliary malignancies.

Methods: A retrospective, IRB-approved chart review was performed of 722 patients receiving RT for any cancer diagnosis between 1/1/2006 and 12/31/2008. Subjects completed the Functional Assessment of Cancer Therapy General (FACT-G) questionnaire before and after RT. Pre- and immediately post-RT course scores were compared using student t-tests with Bonferroni correction for multiple comparisons (7 comparisons, alpha =.007).

Results: 722 of 1369 (52.7%) patients participated in the Patient Related Outcome database. Complete pre and post RT spirituality data were available for 73 (64.6%) patients with GI malignancies, including 24 (33%) with pancreatic or hepatobiliary disease. Average age was 61, 15 (63%) were male and 14 (58%) received definitive treatment. A decrease in both functional and physical well-being was demonstrated in post-RT scores as compared to pre-RT. Emotional well-being, however, increased (17.60 to 18.72, p=0.051), a trend not replicated in any of the other GI malignancies. Further analysis demonstrated this improvement was largely due to a decrease in positive response to the statements “I feel nervous” (1.21 to 0.67, p=0.009) and “I worry my condition will get worse” (1.58 to 1.25, p=0.043). A decrease in positive response to “I feel sad” and an increase in positive response to “I am satisfied with how I am coping with my illness” were also noted, but differences were not significant.

Conclusions: Emotional well-being of those receiving RT for pancreatic and hepatobiliary malignancies appears to improve over the course of therapy, even while other measures of QOL decline. Additional investigations in larger populations are warranted to further elucidate this relationship. Documentation of PROs may have potential for impact on QOL for patients with these and other malignancies.

No significant financial relationships to disclose.

Estimation of disruption of animal cells by laminar shear stress

Using mechanical cell properties measured by micromanipulation, and a model of cell distortion in laminar flow fields, a method has been developed for predicting disruption of animal cells by laminar shear stresses. Predictions of the model were compared with measured losses of cell number and viability of TB/C3 murine hybridomas sheared in a cone and plate viscometer at shear rates up to 3950 s(-1), and shear stresses up to 600 Nm(-2), achieved by enhancement of viscosity with dextran. In all cases, the experimental, results and predictions were within 30%. Such excellent agreement suggests it might be possible to use micromanipulation measurements of animal cell mechanical properties to predict cell damage in more complex flow fields, such as those in bioreactors.

Morphology and clavulanic acid production of Streptomyces clavuligerus: Effect of stirrer speed in batch fermentations

Streptomyces clavuligerus ATCC 20764 was grown from spore-inocuia on a glycerol, malt extract, bacteriological peptone medium in 5-L batch fermentations at 490, 990, and 1300 rpm. Dry cell weights, clavulanic acid production, and the morphological parameters main hyphal length, total hyphal length, number of tips, and hyphal growth unit were measured. Growth and productivity were hardly dependent on stirrer speed. After early growth fragmentation of long, highly branched mycelia to shorter, less branched fragments occurred. This was followed by regrowth and, at 1300 rpm, a second fragmentation phase. The effect of increasing stirrer speed was to accelerate the initial fragmentation phase. It was clearly possible to obtain the same biomass concentration and clavulanic acid liter, with different morphologies depending on stirrer speed. This shows that for this fermentation at least there is no direct link between morphology and productivity and, hence, that it might be possible to manipulate them independently to improve fermentor performance.

A structured model for hyphal differentiation and penicillin production using Penicillium chrysogenum

A structured kinetic model describing growth, differentiation, and penicillin production in submerged Penicillium chrysogenum fermentations is reported. The filamentous hyphae are divided into four distinct regions on the basis of the activities and structure of hyphal compartments, viz., actively growing (mainly apical) regions, nongrowing or penicillin producing regions, vacuoles, and degenerated or metabolically inactive regions. A mechanistic approach is taken to give quantitative descriptions of differentiation and degeneration as a consequence of vacuolation. The growth and degeneration of vacuoles are expressed in the form of a population balance. The model assumes that newly generated vacuoles appear by differentiation of healthy regions, grow in size with limitation of available substrate, and eventually give rise to empty hyphal compartments. In the model the penicillin production is related to the amounts of the nongrowing regions of the hyphae. The model is used for successful predictions of the amounts of the four hyphal regions and the penicillin G production rate throughout the fed-batch fermentations of an industrial P. chrysogenum strain under different glucose feeding regimes. Quantitative information on proportions of the hyphal regions was obtained from image analysis measurements and the parameters of the kinetic model were identified. When the glucose feed rate to the production culture is switched between a high and a low value, the model can successfully predict the dynamic changes of differentiation and the resulting penicillin production caused by the variations in the nutrient conditions. The use of image analysis to characterize differentiation as a basis for structured modeling of the penicillin fermentation appears to be very powerful, and the method has great potential for use in process simulation and control of antibiotic fermentations.

A unique case of Hajdu-Cheney syndrome and squamous cell carcinoma of the anus

OBJECTIVE

Hajdu-Cheney syndrome (HCS), first described in 1948 by Hajdu and independently in 1965 by Cheney, is an extremely rare disorder characterized by severe and excessive bone resorption leading to osteoporosis, with a wide range of other systemic complications from connective tissue and bone dysplasia. Currently there are approximately 50 distinct cases reported in the literature. There have been several reports associating polycystic kidneys with HCS and several other connective tissue disorders, suggesting a possibility of a hyperproliferative component to the syndrome. No articles exist in the current literature describing a case of HCS with concurrent carcinoma. Here, we present a case of a 54-year-old nonimmune compromised woman with multiple stigmata of HCS and recently diagnosed anal squamous cell carcinoma.

METHOD

This is a case report of HCS and stage T3N0 squamous cell carcinoma of the anus.

RESULTS

This is the first report of a patient with HCS with malignancy.

CONCLUSIONS

We present a patient with HCS who developed anal squamous cell carcinoma. The mechanism of HCS, which is still unknown, may either make patients more susceptible to carcinoma or may just be a reflection of the normal incidence of anal squamous cell carcinoma given attributable risk factors.

Oxaliplatin (OXP) plus protracted infusion 5-fluorouracil (PIFU) and external beam radiation (EBRT) prior to surgery (S) for potentially curable esophageal adenocarcinoma (EA): A Southwest Oncology Group (SWOG) phase II trial with molecular correlates (S0356)

4513

Background: Although neoadjuvant combined modality therapy (NACMTX) has become a standard of care in the United States, median overall survival (OS) for patients (PTS) with EA has changed little over the past 25 years. Progression free survival (PFS) and OS after NACMTX depend on extent of primary tumor response. New regimens to increase pathologic complete response (pCR) are needed. Based on phase I data, SWOG designed a phase II trial (S0356) to test OXP with PI5FU and EBRT for PTS with EA. Objectives included pCR rate ≥ 25%, acceptable toxicity (TOX), PFS, OS and exploration of molecular parameters relevant to pCR. Methods: Eligibility: clinical stage II/III EA, ≥ 18 years, Zubrod PS ≤ 2, standard hematologic/non-hematologic values, and tumor < 2 cm into the gastric cardia. OXP 85 mg/m2 was given day (d) 1, 15 and 29; PI5FU 180 mg/m2/d was given d 8-d43. EBRT 180 cGy/d started d 8 x 25 fractions, 5 d/week to total dose 4500 cGy. S was planned 2–4 weeks after NACMTX, with a second cycle of OXP/ PI5FU after S. Central pathology review of surgical specimens was mandated. The trial used a 2-stage design; the trial was halted at 45 PTS to review pCR rate; it reopened to full accrual. Results: 98 PTS enrolled between 9/15/04 and 8/18/08. 6 PTS were ineligible; 2 PTS did not receive therapy (TX). 90 PTS, 84 men (93%), median age 61.7 years, were analyzed. 4 deaths (4.5%) were due to protocol TX; 2 due to NACMTX, 2 to S. 43% and 18% of PTS had grade 3/4 toxicity, respectively: 39% GI, 22% flu-like/fatigue, 17% pulmonary, 16% hematologic, 14% mucositis and 3% neurologic. 77 PTS (86%) underwent S. 30 PTS (33%) had pCR. 9 PTS (10%) had in-situ cancer or T1N0M0. <50% received postoperative CTX. Conclusions: OXP, PI5FU and EBRT for PTS with EA has produced the highest pCR rate reported to date for a cooperative group trial. Significant but manageable non-hematologic TOX was observed. S mortality is acceptable. Future trials built on this platform should plan to complete all TX before S. Tumor molecular profiles (analyses in progress) may predict benefit from this treatment. Data on PFS and OS will follow.

[Table: see text]

pH and expansin action on single suspension-cultured tomato (Lycopersicon esculentum) cells

The aim of this study was to measure key material properties of the cell walls of single suspension-cultured plant cells and relate these to cell-wall biochemistry. To this end, micromanipulation was used to compress single tomato cells between two flat surfaces until they ruptured, and force-deformation data were obtained. In addition to measuring the bursting force, we also determined the elastic (Young's) modulus of the cell walls by matching low strain (< or = 20% deformation) experimental data with a cell compression model, assuming linear elastic cell walls. The walls were most elastic at pH 4.5, the pH optimum for expansin activity, with an elastic modulus of 2.0 +/- 0.1 GPa. Following the addition of exogenous expansins, cell walls became more elastic at all pH values. Western blot analysis of proteins from walls of cultured cells revealed the presence of expansin epitopes, suggesting that the inherent pH dependence of elasticity and other compression phenomena is related to the presence of endogenous expansin proteins and their wall-loosening ability. Although strict application of the linear-elastic model could not be applied to large deformations-for example, up to cell bursting-because of irreversible behaviour, the deviation of the data from the model was generally small enough to allow estimation of the strain in the cell wall at failure. This strain was greater at pH 4.5 and when expansins were added to the suspension. The changes in elasticity are consistent with suggestions about the mode of expansin action. The estimated strains at failure are compatible with data on the failure of Acetobacter-derived cellulose-xyloglucan composites and proposed mechanisms of such failure. Through the measurement of cell-wall material properties using micromanipulation, it may be possible to understand more fully how cell-wall composition, structure and biochemistry lead to cell mechanical behaviour.

Psychiatric illness delays diagnosis of esophageal cancer

Evidence suggests that patients with psychiatric illnesses may be more likely to experience a delay in diagnosis of coexisting cancer. The association between psychiatric illness and timely diagnosis and survival in patients with esophageal cancer has not been studied. The specific aim of this retrospective cohort study was to determine the impact of coexisting psychiatric illness on time to diagnosis, disease stage and survival in patients with esophageal cancer. All patients with a diagnosis of esophageal cancer between 1989 and 2003 at the Portland Veteran's Administration hospital were identified by ICD-9 code. One hundred and sixty patients were identified: 52 patients had one or more DSM-IV diagnoses, and 108 patients had no DSM-IV diagnosis. Electronic charts were reviewed beginning from the first recorded encounter for all patients and clinical and demographic data were collected. The association between psychiatric illness and time to diagnosis of esophageal cancer and survival was studied using Cox proportional hazard models. Groups were similar in age, ethnicity, body mass index, and history of tobacco and alcohol use. Psychiatric illness was associated with delayed diagnosis (median time from alarm symptoms to diagnosis 90 days vs. 35 days in patients with and without psychiatric illness, respectively, P < 0.001) and the presence of advanced disease at the time of diagnosis (37% vs. 18% of patients with and without psychiatric illness, respectively, P= 0.009). In multivariate analysis, psychiatric illness and depression were independent predictors for delayed diagnosis (hazard ratios 0.605 and 0.622, respectively, hazard ratio < 1 indicating longer time to diagnosis). Dementia was an independent risk factor for worse survival (hazard ratio 2.984). Finally, psychiatric illness was associated with a decreased likelihood of receiving surgical therapy. Psychiatric illness is a risk factor for delayed diagnosis, a diagnosis of advanced cancer, and a lower likelihood of receiving surgical therapy in patients with esophageal cancer. Dementia is associated with worse survival in these patients. These findings emphasize the importance of prompt evaluation of foregut symptoms in patients with psychiatric illness.

Factors associated with long-term survival following stem cell transplantation (SCT) for non-Hodgkin lymphoma

18504

Background: Psychosocial variables have been associated with survival in stem cell transplantation recipients. The purpose of this study was to examine the relationship between clinical, psychosocial, and demographic variables and long-term survival. Methods: Autologous SCT recipients with NHL (n=315) from 1/92 - 4/05 (mean age = 51.6 yrs (±12); 35% F; 7% AA; median survival/follow-up = 4.4/ 6.1 yrs) completed the Center for Epidemiologic Studies-Depression Scale, Functional Assessment of Cancer Therapy- BMT (FACT-BMT; physical well-being, PWB), Profile of Mood States, and the Medical Outcomes Study Social Support Survey (MOS-SS) prior to transplantation. Clinical and demographic data were abstracted from the patient’s record. Cox’s proportional hazards regression models were used to assess the effect of the following variables on survival: clinical - histological subtypes (HS) [anaplastic large cell (ALC), diffuse large B-cell (DLBC), mantle cell (MC), indolent, and aggressive], grade, stage, type of conditioning regimen (TC), chemosensitivity (CS), number of chemotherapy regimens (1–7) prior to SCT (NCR); demographic - age, race, gender; and psychosocial - depressed mood, general distress, quality of life, and social support. Measures with a univariate p-value <0.2 were fit in a backwards stepwise regression; remaining variables had a p-value < 0.05. Results: The included univariate model variables (p-values) were: HS (0.0004), grade (0.004), TC (0.14), CS (0.0001), NCR (0.02), PWB (0.03), FACT-BMT subscale (0.16), SS-Emotional (0.05), SS-affection (0.13). In the regression model, predictors of survival were: HS (<0.0001), median survival = ALC 1.9, DLBC 2.7, aggressive 3.3, MC 5.1, indolent 8.4 yrs; CS (0.008); NCR (0.03), and PWB(0.03). Conclusions: Clinical variables were the most predictive of survival. Psychosocial variables were not associated with survival.

No significant financial relationships to disclose.

A regression model for predicting conditional survival for head and neck cancer patients: A SEER analysis

6527

Background: Survival probability changes as patients survive longer periods of time after diagnosis, and estimates of prognosis at diagnosis are no longer valid. Conditional survival (CS) accounts for the changing hazard rate over time and is a more accurate estimate of survival probability for these cancer survivors. The specific aim of this project was to build a statistical model and web-based tool to predict conditional survival for an individual head & neck cancer patient based on tumor and patient characteristics. Methods: Using 27,825 patients diagnosed with head & neck cancer between 1988–97 from the Surveillance, Epidemiology, and End Results 17 (SEER) database, we built a multivariate Cox proportional hazards regression prediction model. Patient and tumor characteristics included as covariates were age, sex, race, tumor site, stage, and grade. The primary endpoint was conditional overall survival. The model was validated for discrimination using the concordance index and a calibration plot was constructed. Bootstrapping was used to correct for optimistic bias. We also built a web-browser software tool to allow a user to enter patient information into the model and calculate conditional survival probability. Results: The regression model showed very good calibration and discrimination with a bootstrap-corrected C-index of 0.71. For a 65-yr old white male with a moderately-differentiated tonsil cancer with regional lymph nodes, the model predicted that the 5-yr conditional overall survival would increase from 50% at the time of diagnosis to 63% at 3 years after diagnosis. For a 75-yr old black male with a well-differentiated localized lip cancer, 5-yr conditional survival would improve from 58% at diagnosis to 70% by 3 years from diagnosis. Conclusions: Our regression model can accurately predict conditional survival for head & neck cancer patients based upon specific patient and tumor characteristics. This tool allows the calculation of more specific prognosis predictions for individual cancer patients who have already survived a period of time after diagnosis and treatment.

No significant financial relationships to disclose.

The role of radiation therapy in benign diseases

Although adequate prospective data are lacking, radiation therapy seems to be effective for many benign diseases and remains one of the treatment modalities in the armamentarium of medical professionals. Just as medication has potential adverse effects, and surgery has attendant morbidity, irradiation sometimes can be associated with acute and chronic sequelae. In selecting the mode of treatment, most radiation oncologists consider the particular problem to be addressed and the goal of therapy in the individual patient. It is the careful and judicial use of any therapy that identifies the professional. With an understanding of the current clinical data, treatment techniques, cost, and potential detriment, the goal is to provide long-term control of the disease while minimizing unnecessary treatment and potential risks of side effects. The art lies in balancing benefits against risks.

Dose intensity comparison of African-American and white patients in NSABP breast treatment trials of postoperative doxorubicin and cyclophosphamide

6111

Background: It has been proposed that ethnic neutropenia in African-American (AA) breast cancer patients leads to lower chemotherapy dose intensity (DI) compared to white (W) patients and hence to increased mortality from the disease [Hershman 2003]. Thomas et al. [2005] confirmed that AA patients in NSABP breast treatment trials had lower WBC and ANC than W counterparts and found that the total amount of chemotherapy received was no different in AA and W patients. The aim of the present study was to extend previous work to determine whether postop doxorubicin (A) and cyclophosphamide (C) DIs (as opposed to total doses) were lower in AA pts enrolled in NSABP breast cancer adjuvant treatment trials. Methods: Pooled data from AA and white (W) pts enrolled in NSABP trials B-15, B-16, B-18 (postop pts only), B-22, B-23, and B-25 (N=10,678 total: 1,040 AA pts and 9,638 W pts) were analyzed. Outcome measures were 1) total A received as a % of the total dose projected on the basis of BSA divided by total days of chemotherapy and 2) corresponding % of C divided by total days of chemotherapy. These quantities were compared in AA and W pts using ANOVA with adjustment for protocol, BMI, G-CSF use, C regimen (600mg/m2 ×4, 1200mg/m2 ×2, 1200mg/m2 ×2, 2400mg/m2 ×2, 2400mg/m2 ×4), and significant pairwise interactions among these variables. Results: After adjustment for the above-listed factors, AA was not a significant predictor of dose intensity for either A or C (p = 0.24 for both comparisons). Conclusions: This retrospective exploratory analysis suggests that despite lower baseline WBC and ANC, AA pts enrolled in these NSABP trials did not receive substantially lower A and C DI than did W pts. Recommending identical dose regimens for AA and W patients in AC-based breast treatment trials is thus most likely clinically reasonable.

No significant financial relationships to disclose.

Image-guided intensity modulated radiation therapy (IG-IMRT) affords increased survival for biliary tract tumors: Results from preliminary analysis

4131

Background: The purpose of this study is to determine the effect of image-guided radiotherapy on survival in adenocarcinoma of the biliary tract. Methods: Between 1995 and 2005, 43 pts with primary biliary tract (gallbladder or bile duct) neoplasms were treated with radiotherapy. 26 of the pts were female and 17 were male. Their average age at registration was 64, and ranged from 25 to 86. Twenty-five pts (58%) were Hispanic, while 18 (42%) were white. 31 pts (72%) underwent surgical treatment, most having cholecystecomy (50%). 29 pts (67%) had chemotherapy: 21 (72%) were given fluorouracil-based drugs, 2 (7%) received gemcitabine, and 6 (21%) received other agents. 23 pts (53%) received conventional radiation treatment using AP/PA, AP/PA with opposing lateral, or AP with opposing lateral fields. 20 pts (47%) received IG-IMRT using Nomos Peacock and daily ultrasound image guidance (BAT, Nomos, Cranberry, PA). For daily ultrasound-based image-guidance, sagittal and axial ultrasound images were acquired, and used to align pt anatomy through superimposition of CT derived organ and vascular guidance structures. Pts were treated using a boost technique to a reduced volume at gross disease after an initial dose to gross tumor and clinically evident microscopic disease. Results: Median dose to target was 54 Gy, with median conventional and IG-IMRT total doses of 48.6 and 60 Gy respectively (p=0.05). Treatment was well tolerated, with only two patients reporting RTOG grade 3 toxicity. All other patients exhibited Grade ≤2, with 23/43 reporting Grade ≤1 The median survival time from the date of registration for all patients was 8.7 months; conventional RT pts had a median survival of 6.1 months, while the IG-IMRT cohort had a median survival of 11.4 months (p = .02). Conclusions: Ultrasound-based image-guided IMRT is a feasible mechanism of delivering moderate dose escalation in conjunction with tighter safety margins, resulting in acceptable acute toxicities. Early survival data with this novel technique are encouraging and demonstrate a notable survival differential using image guided radiotherapy as component of multi-modaility regimens.

No significant financial relationships to disclose.

Conditional survival for patients with colon cancer: An analysis of National Surgical Adjuvant Breast and Bowel Project (NSABP) trials C-03 through C-06

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Background: Survival for cancer patients is usually only reported as survival from time of diagnosis to some time landmark (e.g., 5 yrs). For pts surviving one or more years after diagnosis, however, their survival probability changes, and is more accurately depicted by conditional survival (CS), defined as the probability of surviving for an additional fixed time interval given that the pt has already survived a period of time. The purpose of this study was to determine the 5-yr CS of colon cancer pts in 4 NSABP trials. Methods: We analyzed long-term overall survival data from the 5587 colon cancer pts who were enrolled in fluorouracil (or equivalent) arms of NSABP trials C-03 through C-06. We computed observed 5-yr overall CS for pts who had already survived without disease from 0 to 5 yrs after diagnosis, and stratified the results by age, sex, race, stage, number of positive nodes, number of nodes resected, tumor location, and performance status. Results: The Table below shows the 5-yr overall CS for all pts and for selected subgroups for different survival times since diagnosis. As disease-free survival time since diagnosis increased, 5-yr observed overall CS increased from 76% to 90% at 5 yrs. For pts under age 50, CS increased from 78% to 95% at 5 yrs, but for pts > 70 yrs, CS remained fairly constant (71–82%). For pts with > 10 positive nodes, CS increased from 37% to 81% at 5 yrs, but did not change appreciably for node-negative pts (87–92%). Dukes’ C pts saw an increase in CS from 68% to 88% at 5 yrs, while CS for Dukes’ B pts did not change appreciably. Conclusion: Projected survival probability generally increases with time for colon cancer pts who remain disease-free for a period of time after diagnosis, and conditional survival can provide more informative prognostic information for these pts. An additional effect is that prognostic factors that are important at baseline become less important for conditional survival as the disease-free period increases.

[Table: see text]

No significant financial relationships to disclose.

Conditional survival probability for head and neck squamous cell cancer: Results from the SEER 11 Dataset

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Background: Survival for most cancers is typically reported as a 5-yr percentage from the time of diagnosis. Surviving patients e.g., desire to know if their likelihood for survival has improved, given that they have lived X-years since diagnosis. Conditional survival (CS) is a calculated probability of survival that demonstrates the changing likelihood of demise during a span of intervals after diagnosis. The specific aim of this study is to assess the CS for patients with head and neck squamous cell carcinoma (HNSCC). Methods: The study population included HNSCC patients from the Surveillance, Epidemiology, and End Results (SEER 11) Program. Cumulative survival rates were calculated using JMP v6 (SAS, Cary, NC) with the product-limit method, and derived on the basis of the subsequent annual survival data. Results were also sub-stratified by site of disease. Results: 90,526 patients with histologically confirmed HNSCC diagnosed from 1973 to 2001 were included. The cumulative HNSCC crude cohort 5-year CS at diagnosis is 33%, and 38% at one-year after diagnosis. 5-year CS is 43% at 2 years post-diagnosis, where it plateaus for the next 8 one-year intervals. Sub-site analysis reveals similar CS trends for all HNSCC sites except the nasopharynx. Nasopharynx cancer CS, in contrast, progressively increases over all intervals. Conclusions: HNSCCC 5-year mortality risk stabilizes within 2–3 years after diagnosis, and with the exception of nasopharyngeal cancers, does not substantially improve thereafter. The SEER data represent the largest pooled dataset for HNSCC, but do not necessarily address all relevant issues contributing to risk for death. These data, however, do provide useful estimates for HNSCC patients with known survival after diagnosis, and may have utility in the design of clinical trials which incorporate survival modeling.

[Table: see text]

No significant financial relationships to disclose.

Conditional survival in gallbladder carcinoma: Results from the SEER 11 dataset

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Background: Traditionally, survival is reported as 5-or10-yr survival from diagnosis. However, the 5-yr probability of demise changes considerably with each year survived in many cancers. Clinicians may utilize conditional survival to estimate risk over time. Gallbladder cancer is a rare neoplasm with little extant data with regard to risk assessment for patients with one or more years survival post-therapy. The specific aim of this study is to assess the conditional survival of patients with gallbladder adenocarcinoma using data extracted from the Surveillance, Epidemiology, and End Results (SEER 11) Program. Methods: Cumulative observed survival rates were calculated by the life-table method using SEER data for 3744 patients with histologically confirmed gallbladder adenocarcinoma (diagnosed from 1973 to 2001). On the basis of the cumulative survival estimates, we derived the conditional survival, defined as the calculated probability of survival having already survived a specified number of years from diagnosis, with sub-stratification by extent of disease. Results: Conditional survival calculations reveal dismal 5-year survival at diagnosis (Figures 1 and 2), with increasing probability of survival per each year survived. However, conditional survival plateaus at approximately 60–70% at 4 years post-diagnosis, with little change in conditional survival until 10 years. Conclusions: This dataset represents the largest pooled data for gallbladder carcinoma, and is markedly larger than any given institutional series. Consequently, while imperfect, this data represents a useful estimate for patients with considerable post-diagnosis survival. Although the disease-free survival outcomes for patients with gallbladder adenocarcinoma remain low, for those patient surviving even 1 year post-diagnosis, conditional survival estimates increase rapidly.

[Table: see text]

No significant financial relationships to disclose.

A SEER database analysis of conditional survival for prostate cancer patients

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Background: Survival probability changes for patients who have already survived one or more years following diagnosis, and is more accurately represented by conditional survival. The specific aims of this study were to determine the 5-year conditional survival rates for prostate cancer patients. Methods: Using the Surveillance, Epidemiology, and End Results (SEER 11) database from the NCI, we analyzed 66,822 prostate cancer patients diagnosed between 1988 and 1994 that were staged using the SEER-modified AJCC staging system (3rd edition). Using the life table method, we computed observed 5-year conditional survival, stratified by stage, age, and race, for patients who had already survived 0 to 5 years after diagnosis. Results: For each category, we compared baseline 5-year observed survival at diagnosis with 5-year observed conditional survival after having already survived 5 years. Survival decreased from 79% to 67% for Stage I, decreased from 80% to 71% for Stage II, decreased from 83% to 75% for Stage III, but increased from 38% to 49% for Stage IV patients. Survival rates did not change for patients <70 years (79–80%), but decreased from 61% to 55% for patients >70 years old. Although blacks (60–62%) had lower survival than whites (69–71%), no race had any appreciable change in their conditional survival for those who had survived 5 years from diagnosis. Conclusions: For prostate cancer patients who have already survived some time after diagnosis, the expected 5-year conditional survival increases for Stage IV patients, but decreases for other stages and for older patients. Conditional survival can provide more accurate longer term prognostic information for prostate cancer patients who have already survived a number of years after diagnosis.

No significant financial relationships to disclose.

Evaluation of comparative survival based on the AJCC 5th and 6th editions for breast cancer staging: 25 year experience in two southwest Washington state community cancer programs

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Background: The revised American Joint Committee on Cancer (AJCC) sixth edition (6th ed.) cancer staging system increased stratification within breast cancer (BC) stages II and III defined by the AJCC 5th ed. system. The specific aim of this study was to determine and compare disease-free survival (DFS) for stage 0-III breast carcinoma between the 5th and 6th editions using retrospective data gathered from 1980–2004 in southwest Washington state (WA). Methods: 4,810 patients (pts) were identified using cancer registries at Saint John Medical Center in Longview, WA and Southwest Washington Medical Center in Vancouver, WA. Patients were restaged retrospectively using the 5th and 6th ed. systems. DFS was determined using the Kaplan-Meier method and compared using the log-rank test. Results: The age at diagnosis ranged 20–99 yrs, with a mean age = 60. The mean length for disease-free follow-up was 224 mos. Stage 0 and stage 1 criteria were unchanged between editions, and 10-yr DFS was 94% and 87% for stage 0 and stage 1, respectively. In stage II pts, 13% (199/1,519) were upstaged to stage III by the 6th ed. criteria, significantly improving the 10-yr DFS for stage II from 66% (5th ed.) to 72% (6th ed; p = 0.003). The majority, 85% (167/199), of pts upstaged were from the 539 classified as stage IIb disease by the 5th ed. This accompanied an increase in the 10-year DFS for stage IIb from 54% (fifth) to 62% (sixth; p = 0.046). The number of pts with stage III disease increased from 313 to 588 in the 6th ed. 10-year DFS increased from 30% to 36% (p = 0.025), respectively. Most of this increase resulted from changes within stage IIIa, as DFS increased from 32% to 41% (p = 0.046). When compared, DFS outcomes between stage IIIb and IIIc were not found to be statistically significant (p = 0.501). Conclusions: The AJCC 6th ed. system for BC provides greater distinctions between stages compared to the 5th ed., and reclassification results in significant changes in projected outcomes. However, the addition of the IIIc substage does not seem to show the same significant distinction when compared to the existing stage IIIb substage in outcomes.

No significant financial relationships to disclose.

Risk of cardiac (CD) and pulmonary (PD) death after post-operative radiotherapy (PORT) for non-small cell lung cancer (NSCLC): Analysis of the Surveillance, Epidemiology, and End-Results (SEER) program

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Background: Since radiation treatment planning and delivery techniques have evolved over time, we investigated if the risk of CD and PD after PORT for NSCLC has decreased. Methods: We selected postoperative patients with non-metastatic NSCLC diagnosed in 1980–1995 from the SEER data. To account for peri-operative mortality, patients with survival less than 6 months were excluded. Variables analyzed included age, gender, laterality, disease stage, SEER geographic region, ethnicity/race, and histology. CD and PD were calculated at 10 years and compared for patients diagnosed during 1980–83, 1984–88, 1989–91, and 1992–95. Cox proportional hazards models (CPHM) were used to calculate the hazard of CD and PD. Results: This analysis included 29,093 patients treated with observation (OB) and 8334 patients who received PORT. For the patients treated with OB, the 10 yr mortality rates for CD/PD were 17%/2%, 15%/3%, 15%/3%, and 14%/<0.1% for years of diagnosis of 1980–83, 1984–88, 1989–91, and 1992–95, respectively. For the patients who were treated with PORT, the 10 yr mortality rates for CD/PD were 21%/3%, 21%/4%, 15%/4%, and 14%/<0.1% for years of diagnosis of 1980–83, 1984–88, 1989–91, and 1992–95, respectively. CPHM showed the hazard of CD for patients treated with OB to be significantly decreasing; 1980–83 (HR=1.412; CI=1.257–1.585; p<0.0001), 1984–88 (HR=1.260; CI=1.124–1.413; p<0.0001), 1989–91 (HR=1.180; CI=1.054–1.321; p=0.0042), and 1992–95 (HR=1.00; Ref.). CPHM showed the hazard of CD for patients who received PORT to be significantly decreasing; 1980–83 (HR=1.568; CI=1.222–2.011; p=0.0004), 1984–88 (HR=1.435; CI=1.125–1.830; p=0.0036), 1989–91 (HR=0.992; CI=0.767–1.282; p=0.9504), and 1992–95 (HR=1.00; Ref.). Although PD showed a similar decreasing trend relative to year of diagnosis, CPHM did not demonstrate this to be statistically significant. Conclusions: There was a greater reduction in the CD rate in the PORT group compared to the OB group. While there appeared to be a trend in the reduction of PD, the results were not significant which may be secondary to too few events occurring.

No significant financial relationships to disclose.

The current role of staging laparoscopy for adenocarcinoma of the pancreas: a review

In the absence of metastatic disease patients with localized or locally advanced pancreatic cancer can benefit from surgical resection or chemoradiation. Despite the advances of imaging technology, however, noninvasive staging modalities are still inaccurate in identifying small volume metastatic disease leading potentially to inappropriate treatment and avoidable morbidity in a subgroup of patients. Staging laparoscopy may identify those patients with unsuspected metastatic disease on preoperative imaging and prevent unnecessary laparotomy or chemoradiation. A controversy exists, however, as to whether the procedure should be used routinely or selectively in pancreatic cancer patients with no evidence of metastasis on noninvasive staging. This review aims to assess the current role of staging laparoscopy by examining its diagnostic accuracy and ability to prevent unnecessary treatment as well as its morbidity, oncologic effect and cost-effectiveness. The available literature will be evaluated critically, its limitations identified and exisiting controversies addressed.

Current and ongoing progress in the therapy for resectable esophageal cancer

There have been recent advances in the surgical approach to respectable esophageal cancer. In addition, despite the paucity of level 1 data, regardless of histology (squamous cell or adenocarcinoma), neo-adjuvant chemoradiotherapy has evolved into a de facto standard of care for resectable disease. Pathologic response rate is a surrogate for a more favorable outcome. In addition, there are a number of molecularly targeted agents that may have clinical utility for these patients. Current clinical trials have been designed with a translational research component to define which patients may benefit from the incorporation of these novel agents alongside standard combined-modality approaches.

Genotype, obesity and cardiovascular disease--has technical and social advancement outstripped evolution?

Teleologically, our ancestors were highly adapted hunter-gatherers. In recent history, the environment in which Homo sapiens exists has altered drastically and humans are exposed to environments for which the hunter-gatherer genotype is ill-suited. The adoption of a sedentary Western lifestyle, and the case of obtaining food of a high calorific content imposed upon a thrifty genotype, have resulted in the current global epidemic of obesity, Type 2 diabetes and the Metabolic Syndrome. The ramification of this epidemic is that cardiovascular disease is becoming a global healthcare problem, which will have its greatest impact on the developing nations. A global strategy is required to reduce the impact of the Western lifestyle on the health of developing nations and prevent obesity and Type 2 diabetes. Such an approach needs to be culturally sensitive, integrated, and multidisciplinary and involve a range of interventions that work at the individual and community levels. If lifestyle measures fail, then pharmacological intervention may be necessary. For this, novel agents such as dual PPARalpha/gamma agonists may be the therapy of the future.

Phase III trial comparing whole-pelvic versus prostate-only radiotherapy and neoadjuvant versus adjuvant combined androgen suppression: Radiation Therapy Oncology Group 9413

PURPOSE

This trial tested the hypothesis that combined androgen suppression (CAS) and whole-pelvic (WP) radiotherapy (RT) followed by a boost to the prostate improves progression-free survival (PFS) by 10% compared with CAS and prostate-only (PO) RT. This trial also tested the hypothesis that neoadjuvant and concurrent hormonal therapy (NCHT) improves PFS compared with adjuvant hormonal therapy (AHT) by 10%.

MATERIALS AND METHODS

Eligibility included localized prostate cancer with an elevated prostate-specific antigen (PSA) < or = 100 ng/mL and an estimated risk of lymph node (LN) involvement of 15%. Between April 1, 1995, and June 1, 1999, 1,323 patients were accrued. Patients were randomly assigned to WP + NCHT, PO + NCHT, WP + AHT, or PO + AHT. Failure for PFS was defined as the first occurrence of local, regional, or distant disease; PSA failure; or death for any cause.

RESULTS

With a median follow-up of 59.5 months, WP RT was associated with a 4-year PFS of 54% compared with 47% in patients treated with PO RT (P =.022). Patients treated with NCHT experienced a 4-year PFS of 52% versus 49% for AHT (P =.56). When comparing all four arms, there was a progression-free difference among WP RT + NCHT, PO RT + NCHT, WP RT + AHT, and PO RT + AHT (60% v 44% v 49% v 50%, respectively; P =.008). No survival advantage has yet been seen.

CONCLUSION

WP RT + NCHT improves PFS compared with PO RT and NCHT or PO RT and AHT, and compared with WP RT + AHT in patients with a risk of LN involvement of 15%.

Sensitivity of cell hydraulic conductivity to mercury is coincident with symplasmic isolation and expression of plasmalemma aquaporin genes in growing maize roots

Root elongation occurs as individual cells along the growing zone increase in volume. This increase is caused by water entering the cell either by moving across the cell membrane from the apoplast via aquaporins, or entering through plasmodesmata that symplastically connect cells to each other or with the sieve element. In this investigation we used mercury, a known inhibitor of aquaporin water channels, to manipulate the water permeability of growing maize root cells. 20 micro M HgCl(2) was found to reduce root elongation by around 75% and this reduction in growth was greatest in the older growing cells, with little effect on the younger cells near the root tip. Cell hydraulic conductivity (Lp) of cells close to the root tip (at 3 mm) remained unaffected by mercury treatment in contrast to older growing and non-growing cells where Lp was greatly reduced. Using reverse transcription-polymerase chain reaction analysis, younger root regions were shown to express higher levels of two plasmalemma intrinsic protein genes than older root regions further away from the root tip. However, a gene encoding a tonoplast aquaporin was expressed at similar levels in both regions of the growing zone. The fluorescent tracer, carboxyfluorescein, demonstrated symplastic connection between the phloem and root cortical cells at 3 mm but not at 5 or 20 mm. The data are consistent with a decrease in symplastic continuity along the growing zone and highlight a change in the principal pathway of water uptake during the development of the growing root cell.

Decreasing the hyphal branching rate of Saccharopolyspora erythraea NRRL 2338 leads to increased resistance to breakage and increased antibiotic production

Mutation and selection for increased resistance to cell-wall synthesis inhibitors led to alterations in the hyphal branching rate of Saccharopolyspora erythraea NRRL 2338. Mutants with decreased branching frequency exhibited increased hyphal strength (estimated by in vitro micromanipulation). As the hyphal strength was increased, this led to a greater proportion of hyphal particles in liquid culture with a hyphal fragment diameter of greater than 88 microm. This, in turn, coincided with proportionately increased antibiotic production.

Dependence of morphology on agitation intensity in fed-batch cultures of Aspergillus oryzae and its implications for recombinant protein production

We previously reported that, although agitation conditions strongly affected mycelial morphology, such changes did not lead to different levels of recombinant protein production in chemostat cultures of Aspergillus oryzae (Amanullah et al., 1999). To extend this finding to another set of operating conditions, fed-batch fermentations of A. oryzae were conducted at biomass concentrations up to 34 g dry cell weight/L and three agitation speeds (525, 675, and 825 rpm) to give specific power inputs between 1 and 5 kWm(-3). Gas blending was used to control the dissolved oxygen level at 50% of air saturation except at the lowest speed where it fell below 40% after 60-65 h. The effects of agitation intensity on growth, mycelial morphology, hyphal tip activity, and recombinant protein (amyloglucosidase) production in fed-batch cultures were investigated. In the batch phase of the fermentations, biomass concentration, and AMG secretion increased with increasing agitation intensity. If in a run, dissolved oxygen fell below approximately 40% because of inadequate oxygen transfer associated with enhanced viscosity, AMG production ceased. As with the chemostat cultures, even though mycelial morphology was significantly affected by changes in agitation intensity, enzyme titers (AGU/L) under conditions of substrate limited growth and controlled dissolved oxygen of >50% did not follow these changes. Although the measurement of active tips within mycelial clumps was not considered, a dependency of the specific AMG productivity (AGU/g biomass/h) on the percentage of extending tips was found, suggesting that protein secretion may be a bottle-neck in this strain during fed-batch fermentations.

Viability, strength, and fragmentation of Saccharopolyspora erythraea in submerged fermentation

Two fermentations of the commercially important erythromycin-producing filamentous bacterium Saccharopolyspora erythraea were conducted in defined media. One was glucose-limited and the other nitrate-limited. The viability of the hyphae was determined using the fluorescent stain BacLight (Molecular Probes, Eugene, OR). Also, the force required to strain hyphae to breakage was determined using micromanipulation and a sensitive force transducer. In both fermentations, fragmentation coincided with the appearance of regions in the mycelia with permeabilised membranes (considered nonviable). Under glucose-limitation, hyphal breaking force rose to 1,050 +/- 130 nN at the end of the growth phase and fell to an undetectable value as a result of glucose exhaustion. Under nitrate-limitation, hyphal breaking force fell from 900 +/- 160 nN during the growth phase to 550 +/- 40 nN in the stationary phase. In both cases image analysis showed that the dimensions of mycelia were of the same order, suggesting that the major factor influencing fragmentation was the appearance of nonviable regions (assumed to be weak). The location in which nonviable regions first appear within hyphae could not be determined because of their appearance coinciding with fragmentation.

Atrial natriuretic peptide-like immunoreactivity in neurons and astrocytes of human cerebellum and inferior olivary complex

Atrial natriuretic peptide (ANP) has previously been localized in areas of mammalian brain associated with olfaction, cardiovascular function, and fluid/electrolyte homeostasis. Despite the presence of several types of natriuretic peptide receptors in mammalian cerebellum, neither intrinsic nor extrinsic sources of the natriuretic peptides have been described. In this report we describe the immunohistochemical localization of both intrinsic and extrinsic sources for ANP in human cerebellum. ANP-like immunoreactivity (ANP-LIR) was observed in climbing fibers in the cerebellar molecular layer that probably originated from isolated immunopositive neurons of the inferior olivary complex. Intrinsic sources of ANP-LIR included small subpopulations of protoplasmic and fibrous astrocytes and Bergmann glia, as well as Golgi and Lugaro neurons of the granule cell layer. These results suggest that, in addition to its presumptive roles in local vasoregulation, ANP may serve as a modulator of the activity of Purkinje neurons.