The effect of l-arginine supplementation and surgical trauma on the frequency of myeloid-derived suppressor cells and T lymphocytes in tumour and blood of colorectal cancer patients

PURPOSE

l-arginine (L-arg) deficiency causes immunosuppression, but it is unknown if L-arg supplementation in colorectal cancer (CRC) patients restores immune system activity. Our objective was to investigate the effect of L-arg supplementation on the frequency of monocytic (M) and polymorphonuclear (PNM) myeloid-derived suppressor cells (M-MDSCs and PMN-MDSCs, respectively).

METHODS

We enrolled 65 CRC patients (34 males, 31 females) aged 69 ​± ​10 years into a prospective, randomised, double-blind study. Twenty-eight patients received L-arg and 37 received placebo for 9 days at a dose of 10 ​g/day. The frequency changes in MDSC, CD4⁺ cells and the concentration of C-reactive protein (CRP) were assessed before supplementation with L-arg (test 1), after 9 days of supplementation (test 2), and after surgery on day 11 (test 3).

RESULTS

The frequency of M-MDSC in the tumours of patients receiving L-arg supplementation was higher than in placebo-treated patients, as was the frequency of PMN-MDSC and M-MDSC in the mucosa. CRP concentration in the serum of placebo-treated patients in test 2 was higher than in test 1, and the concentration in the serum of patients with L-arg supplementation in test 2 was lower than in test 1. Moreover, the expression pattern of the argininosuccinate synthase 1 (ASS1) suggests that CRC is not auxotrophic for L-arg.

CONCLUSIONS

The results of this study do not support the hypothesis that L-arg supplementation in CRC patients can reduce immunosuppression by decreasing the frequency of suppressor cells and increasing the frequency of effector CD4⁺ T cells.

Level of inferior mesenteric artery ligation does not affect rectal cancer treatment outcomes despite better cancer-specific survival after low ligation-randomized trial results

AIM

In rectal cancer surgery, the problem about which of the mesenteric artery ligation variants (high or low) is more beneficial to the patient remains unsolved. Recent meta-analyses suggest that the risk of surgical complications is similar for both ligation variants. The main objective was to compare the survival time in both groups with a minimum 48 months' follow-up. Secondary objectives were comparison of the number of harvested lymph nodes, the complication rate and other selected data related to the surgery.

METHOD

This was a randomized, single-centre, unblinded clinical trial of adult patients (n = 130) with cT1-3M0/ycT0-3M0 rectal and rectosigmoid junction adenocarcinoma undergoing radical open surgery. The intervention level was inferior mesenteric artery ligation.

RESULTS

The mean and median survival in the whole group was 45 months, while in the survivor group it was 83 and 82 months. The survival for 1-5 years, overall survival and disease-free survival were similar in both groups. The cancer-specific survival time was longer in the low inferior mesenteric artery ligation group (P = 0.005 for all and P = 0.02 for pTNM Stage III patients) There were no differences in the incidence of anastomotic leakage and overall morbidity. The median number of lymph nodes located at the root of the inferior mesenteric artery was 1; the mean was 1.7. They were not metastatic in any case. The median total number of harvested nodes was similar in both groups.

CONCLUSIONS

In radically treated adenocarcinoma of the rectum and the rectosigmoid junction, the level of inferior mesenteric artery ligation below the left colic artery branch provides similar treatment results to inferior mesenteric artery ligation just below its branching from the aorta in relation to overall and disease-free survival, and the risk of complications. Low inferior mesenteric artery ligation results in better cancer-specific survival. The risk of metastases at the mesenteric nodes is negligible.

Impact of chromosome 17 centromere copy number increase on patient survival and human epidermal growth factor receptor 2 expression in gastric adenocarcinoma

The accurate evaluation of human epidermal growth factor receptor 2 (HER2) status is essential for the appropriate use of targeted therapies. An increased number of chromosome 17 centromere enumeration probe (CEP17) signals may underrate fluorescence in situ hybridization (FISH) outcomes, resulting in false-negative or a false-equivocal HER2 status assessment. The aim of the present study was to assess the frequency of CEP17 copy number increase (CNI), its effects on HER2 protein expression (and the subsequent effects on tumor cells), and the survival outcomes of patients with gastric cancer. Archival primary tumor samples from 244 patients that underwent gastric resection for adenocarcinoma were retrieved for both HER2 protein expression analysis (using immunochemistry) and HER2 gene amplification (using FISH). The associations between HER2 status, CEP17 CNI and multiple clinicopathological parameters (including survival outcome), were assessed. The relationship between CEP17 CNI and HER2 protein upregulation was also investigated. CEP17 CNI was detected in 17.2% of cases, and a strong association between CEP17 CNI and HER2 upregulation was revealed. The impact of CEP17 CNI on survival did not reach statistical significance. Consequently, CEP17 CNI was discovered to be strongly associated with HER2 upregulation in tumor cells, which may characterize a critical issue in HER2 testing. Therefore, the eligibility for HER2-targeted agents in CEP17 CNI-positive patients warrants further recognition.

Characteristics of advanced methods used for typing bacterial isolates from mastitis with particular reference to Staphylococci

Staphylococci are very common human and animal pathogens. A variety of staphylococcal virulence determinates leads to vast range of infections. One of them is mastitis which is a common disease of the mammary glands. The incidence of this disease is widespread all over the world and depends on bacterial virulence and on prevention programs. The influence of mastitis on human health is not globally evaluated, however, in veterinary fields loses in milk production caused by bovine mastitis are a constant economic problem. One of the most important parts of the mastitis control programs is accurate diagnosis of the inflammation and characterization of the etiological factors which leads to reduction of mastitis spread. Recent reports show that staphylococci are common bacterial etiological factors of mastitis, and this paper is an overview of the diagnostic typing methods used for characterization of staphylococcal isolates. A number of different techniques available to applicate is described. Phenotypic methods to identify and to differentiate isolates or discriminate virulence factors are still in use, however, some advanced genetic methods offering higher discriminatory power are reported as more accurate. In fact, nowadays the most powerful tool on that field is next generation sequencing (NGS) of the whole genome, but its high cost and requirement of special laboratory equipment makes it hard to use for routine diagnostics. That is why standard PCR techniques-based methods, and the sequencing of particular genes, are mostly used for typing bacterial isolates. Most of these techniques are characterized by a high discriminatory power, big epidemiological concordance, and repeatable results. The presented report describes the techniques used most frequent in mastitis diagnostics related to staphylococci typing and shows their advantages and disadvantages.

Extremely High Mortality Rate after a Successful Gastrectomy for Cancer in Older Adults

PURPOSE

Poor physiological reserve for withstanding major cancer surgery in older adults is an important concern in the selection of patients for oncologic gastrectomy. The present study aimed to analyze mortality patterns among patients who underwent gastrectomy for cancer according to age groups. The primary outcomes of this study were early- and middle-term results: 30-day and 3-, 6-, 12-, and 36-month mortality rates.

MATERIALS AND METHODS

A retrospective review of 288 patients who underwent surgical resection for gastric cancer in two centers was carried out. Patients were stratified into four groups according to age: 29-50 years (group I, n=27), 51-65 years (group II, n=117), 66-75 years (group III, n=81), and 76-92 years (group IV, n=58). Statistical calculations focused on the differences in the survival rates between groups I and II as well as between groups II and IV.

RESULTS

The middle-aged patients (group II) had significantly better 3-year survival than either the youngest (group I) or the oldest patients (group IV). The 6-month mortality rates were 16.9% in group III and 29.3% in group IV. Two-thirds of the patients from groups III and IV who died between 2 and 6 months after surgery had an uneventful postoperative course.

CONCLUSIONS

Age is an important prognostic factor of middle-term survival after gastrectomy for cancer. Geriatric assessment and better patient selection for major surgery for cancer are required to improve the outcome of gastrectomy for cancer in patients aged over 75 years.

The relationship between HER2 overexpression and angiogenesis in gastric cancer

In gastric cancer, HER2 protein overexpression is considered to be conducive to the higher proliferation activity of the tumor cells. Tumor formation is associated with angiogenesis in order to secure an abundant supply of oxygen and glucose to cancer cells. The aim of the study was to assess if HER2 overexpression is related to higher microvessel density (MVD) in the tumor stroma.The archival samples of primary tumor from 144 consecutive patients that underwent gastric resection for cancer between August 1, 2006 and December 31, 2013 in the Department of Oncological Surgery of Medical University of Gdańsk were analyzed. CD34 was used as a marker of MVD in the tumor stroma. Both CD34 and HER2 protein expressions were tested by immunohistochemistry.The assays were unsuccessful to estimate HER2 in 10 cases and CD34 in 14 cases due to technical reasons. The results were obtained for 128 patients. HER2 0 and HER2 1+ were considered negative, while HER2+ and HER2 3+ were recognized as positive. Mean MVD (mean number of vessels in the visual field) was 32.4 (median 29.5). Microvessel density was insignificantly higher in HER2 positive tumors. The slight difference was also seen between IHC 2+ and 3+ groups. The differences did not reach the level of statistical significance.Statistical analysis performed in our study did not reveal the significant relationship between HER2 overexpression on the tumor cells and MVD in the tumor stroma.

The rate of denitrification using hydrodynamically disintegrated excess sludge as an organic carbon source

This study investigates the potential of hydrodynamically disintegrated excess activated sludge when used as a supplementary carbon source for denitrification. Two objectives constituted this study: (i) to analyse the denitrification rate by using excess sludge subjected to hydrodynamic disintegration (HD), performed at different energy densities, as an organic carbon source, and (ii) to analyse the impact of hydrolysis of disintegrated sludge on the denitrification rate. Nitrate reduction tests were conducted to assess the denitrification rate for the following sources of organic carbon: thickened excess sludge disintegrated at three levels of energy density (70, 140 and 210 kJ/L), acetic acid solution and municipal wastewater after mechanical treatment. It was found that the HD of excess sludge conducted at different levels of energy density led to dissolved organic compounds characterised by various properties as donors of H⁺ in the denitrification process. The susceptibility of disintegrated sludge to anaerobic hydrolysis decreased along with the increasing energy density. The obtained organic carbon contributed to a lower increase in the denitrification rate in comparison to that when disintegrated sludge not subjected to hydrolysis was applied.

Microbiology neutralization of zearalenone using Lactococcus lactis and Bifidobacterium sp

The aim of the study was to neutralize zearalenone by lactic acid bacteria (LAB) such as Lactococcus lactis and Bifidobacterium sp. and investigate the mechanism of zearalenone (ZEA) binding. Neutralization of ZEA by LAB was confirmed by identification of binding kinetics and spectroscopic studies such as Fourier transform infrared spectroscopy (FT-IR) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The obtained results showed that the kinetic process of zearalenone binding to L. lactis is not homogeneous but is expressed with an initial rapid stage with about 90% of ZEA biosorption and with a much slower second step. In case of Bifidobacterium sp., the neutralization process is homogeneous; the main stage can be described with about 88% of ZEA biosorption. MALDI-TOF-MS measurements and FTIR analysis confirmed the uptake of zearalenone molecules by bacterial species. Moreover, the assessment of dead and live lactic acid bacteria cells after zearalenone treatment was performed using fluorescence microscopy. Graphical abstract Microbiology neutralization of zearalenone using Lactococcus lactis and Bifidobacterium sp. was confirmed by identification of binding kinetics and spectroscopic studies such as FT-IR spectroscopy and MALDI-TOF-MS spectrometry. The mechanism of ZEA binding was also investigated.

Same Quality of Life for Polish Breast Cancer Patients Treated with Mastectomy and Breast Reconstruction or Breast-Conserving Therapy

Breast cancer often requires combined oncologic treatments, the base of which is surgery. Quality of life (QoL) after each surgical procedure may influence the process of decision making among women, who qualify for multiple oncological strategies. Our knowledge about QoL in breast cancer patients is derived from comparative studies. Results may differ, depending on country, culture, and societal relations.

was to investigate the quality of life of Polish patients treated with breast-conserving therapy (BCT) or mastectomy with breast reconstruction.

The study involved women who underwent surgery for breast cancer in the Department of Surgical Oncology of the Gdynia Oncology Center from September 2010 to November 2013. Eighty-two breast reconstructions (in 79 patients) and 226 BCT procedures were performed. QoL was measured with the use of EORTC QLQ-C30 and QLQ-BR23 questionnaires.

Global QoL was high in both groups and did not differ significantly. Body image was slightly better after BCT than after mastectomy with breast reconstruction, but sexual QoL was lower. Future perspective was quite low in both groups. Disease symptoms were not bothering.

The global QoL among Polish breast cancer patients treated with BCT or mastectomy with breast reconstruction is high and does not differ between groups. There is a need for anxiety and disease-related fear prophylaxis and for the improvement of sex life of breast cancer survivors.

Interventions to reduce or prevent obesity in pregnant women: a systematic review

BACKGROUND

Around 50% of women of childbearing age are either overweight [body mass index (BMI) 25-29.9 kg/m(2)] or obese (BMI ≥ 30 kg/m(2)). The antenatal period provides an opportunity to manage weight in pregnancy. This has the potential to reduce maternal and fetal complications associated with excess weight gain and obesity.

OBJECTIVES

To evaluate the effectiveness of dietary and lifestyle interventions in reducing or preventing obesity in pregnancy and to assess the beneficial and adverse effects of the interventions on obstetric, fetal and neonatal outcomes.

DATA SOURCES

Major electronic databases including MEDLINE, EMBASE, BIOSIS and Science Citation Index were searched (1950 until March 2011) to identify relevant citations. Language restrictions were not applied.

REVIEW METHODS

Systematic reviews of the effectiveness and harm of the interventions were carried out using a methodology in line with current recommendations. Studies that evaluated any dietary, physical activity or mixed approach intervention with the potential to influence weight change in pregnancy were included. The quality of the studies was assessed using accepted contemporary standards. Results were summarised as pooled relative risks (RRs) with 95% confidence intervals (CIs) for dichotomous data. Continuous data were summarised as mean difference (MD) with standard deviation. The quality of the overall evidence synthesised for each outcome was summarised using GRADE (Grading of Recommendations Assessment, Development, and Evaluation) methodology and reported graphically as a two-dimensional chart.

RESULTS

A total of 88 studies (40 randomised and 48 non-randomised and observational studies, involving 182,139 women) evaluated the effect of weight management interventions in pregnancy on maternal and fetal outcomes. Twenty-six studies involving 468,858 women reported the adverse effect of the interventions. Meta-analysis of 30 RCTs (4503 women) showed a reduction in weight gain in the intervention group of 0.97 kg compared with the control group (95% CI -1.60 kg to -0.34 kg; p = 0.003). Weight management interventions overall in pregnancy resulted in a significant reduction in the incidence of pre-eclampsia (RR 0.74, 95% CI 0.59 to 0.92; p = 0.008) and shoulder dystocia (RR 0.39, 95% CI 0.22 to 0.70; p = 0.02). Dietary interventions in pregnancy resulted in a significant decrease in the risk of pre-eclampsia (RR 0.67, 95% CI 0.53 to 0.85; p = 0.0009), gestational hypertension (RR 0.30, 95% CI 0.10 to 0.88; p = 0.03) and preterm birth (RR 0.68, 95% CI 0.48 to 0.96; p = 0.03) and showed a trend in reducing the incidence of gestational diabetes (RR 0.52, 95% CI 0.27 to 1.03). There were no differences in the incidence of small-for-gestational-age infants between the groups (RR 0.99, 95% CI 0.76 to 1.29). There were no significant maternal or fetal adverse effects observed for the interventions in the included trials. The overall strength of evidence for weight gain in pregnancy and birthweight was moderate for all interventions considered together. There was high-quality evidence for small-for-gestational-age infants as an outcome. The quality of evidence for all interventions on pregnancy outcomes was very low to moderate. The quality of evidence for all adverse outcomes was very low.

LIMITATIONS

The included studies varied in the reporting of population, intensity, type and frequency of intervention and patient complience, limiting the interpretation of the findings. There was significant heterogeneity for the beneficial effect of diet on gestational weight gain.

CONCLUSIONS

Interventions in pregnancy to manage weight result in a significant reduction in weight gain in pregnancy (evidence quality was moderate). Dietary interventions are the most effective type of intervention in pregnancy in reducing gestational weight gain and the risks of pre-eclampsia, gestational hypertension and shoulder dystocia. There is no evidence of harm as a result of the dietary and physical activity-based interventions in pregnancy. Individual patient data meta-analysis is needed to provide robust evidence on the differential effect of intervention in various groups based on BMI, age, parity, socioeconomic status and medical conditions in pregnancy.

A randomized double blind phase I-II study to determine the tolerability/efficacy of two different doses of lenalidomide (L), CC- 5013, in biochemically relapsed (BR) prostate cancer (PC) patients (pts) (M0) after local treatment (LT)

5130

Background: BR following LT is common in PC with no defined standard treatment. Lenalidomide (L) is an immunomodulatory agent with anti-angiogenic and direct antitumor effects. Methods: This trial was designed to evaluate a dose-effect relationship of L in BR PC. Pts were randomized to either 5 or 25 mg/day(d), PO, d 1–21 (28-d cycles); then stratified by PSADT (< 3, 3–8.9, ≥ 9 mos), LT and prior ADT. Eligible pts had: rising PSA (≥1 ng/mL), M0 disease, testosterone > 150 ng/mL, adequate bone marrow, renal, and hepatic function. Baseline and Q 2 mos PSA's were processed after Q 6 mos of L, along with CT and bone scan. Toxicity exams were Q mo. Primary endpoints are safety and progression after 6 mo of L (defined by a confirmed ↑ in PSA > 25% over the baseline value or mets). Secondary endpoints are changes of slopes in PSA related to pharmacokinetics (pk). A sample size of 30 pts/arm provides an 85% power to detect a PSA progression rate of 40% (compared to 80% predicted ) with a Type I error = 0.05 (Fishers exact test). Results: 59 pts were entered July 20, 2006-December 31, 2008. Pooled data from the 2 arms: median: age 64 (50–81), ECOG PS 0, baseline PSA 9.3 ng/ml (1.3–92.8 ng/ml). 16 pts had PSADT <3 mos, 26 from 3–8.9 mos, and 17 ≥ 9 mos. Median: F/U on all 59 pts is 351 + d (9 +-887+d); # cycles = 6 (1–30). Thus far, 44/59 pts completed 6 cycles of L (1 had PD, 6 stopped L due to toxicity, 8 too early). 22 /44 who completed 6 mos of L remained on L > 6 mos ( 7+-30+ mos); including 7 pts ≥ 24 mos. Of 44 pts, blinded evaluation of PSA's at 6 mos: 4 pts had ≥ 50% ↓, 22 had stable PSA,17 had PD, 1 too early . Rash was DLT. Other Gr toxicities: appendicitis, abd pain, neck pain, venous thrombolic disease, fatigue, pruritus. Conclusions: Preliminary data prior to unblinding the study treatment arms, from pooled data, suggest that L may be administered > 6 mos with acceptable toxicity, and is associated with PSA declines and long term stabilization in pts with BR. Supported by a grant from Celgene Corporation. Data coordination infrastructure is supported by the Prostate Cancer Foundation and The James Stine research fund.

[Table: see text]

Phase I trial of docetaxel (D) plus samarium153 (Sm 153) in patients (pts) with hormone refractory prostate cancer (HRPC)

15547

Background: Bone targeted approaches hold great promise for improving outcomes in HRPC. Docetaxel (D) and samarium 153 (Sm153 ) have individually demonstrated a clinical benefit and preclinical data strongly support biological synergism in HRPC. Preclinical data suggests that 24 hour after a dose of D, there is maximum G2M arrest. This results in the accumulation of cells in the most radiosensitive phase of the cell cycle. This phase I trial was designed to evaluate toxicity and preliminary efficacy of combined D and Sm153 administered sequentially in advanced HRPC. Methods: HRPC pts progressing after anti-androgen withdrawal; = 2 prior chemotherapy regimens; acceptable bone marrow, renal and hepatic function were eligible. Planned D treatment in 4 cohorts (N=3/cohort) includes: Cohort 1: D 50mg/m2 IV on days 1, 22, 91, and 112; cohort 2: D 75mg/m2 IV on days 1 and 22 followed by 50mg/m2 IV on days 91 and 112; cohort 3: D 75mg/m2 IV on days 1 and 22 followed by 75mg/m2 IV on days 91 and 112; cohort 4: D 75 mg/m2 IV on days 1, 22, 42, 91, 112, and 133. Sm 153 (1.0 mi/Kg) is administered IV days 2 and 92 of each cycle. Cycles are repeated Q 12 wks (max 2 cycles). The endpoint for this trial is dose limiting toxicity and maximal tolerated dose. Results: From 5/11/05 - 1/7/07 ten pts were enrolled. Median: age 69.5 yrs (range 58–76), ECOG performance status 1 (range 0–1), baseline PSA 76.65 ng/ml (range 9.6–1064 ng/ml ), prior hormonal manipulations 3 (range1–6). Three pts had prior taxotere and 3 pts had prior palliative RT. All had bone metastases and 2 also had soft tissue disease. Five pts completed 2 cycles of treatment as planned. Five pts had 1 cycle (one pt is on treatment, 3 pts had PD and 1 had prolonged grade 1 thrombocytopenia =3 wks). Nine of 10 pts had reversible grade 3 / 4 neutropenia (1 pt had reversible episode of neutropenia with fever). Seven of 7 symptomatic pts had improvement in pain. Four of 10 of pts had a 50 % decline in PSA level lasting = 4 weeks; no soft tissue disease responses. Conclusions: Our preliminary data suggest that Q 3 wk D and Q 3 month Sm153 may be administered simultaneously at full doses in extensively pretreated HRPC pts, with acceptable toxicity and significant activity. This study is supported by a grant from sanofi- aventis and Sm153 is provided by Cytogen.

No significant financial relationships to disclose.

A phase II evaluation of imatinib mesylate (G) in stage M0 prostate cancer (PC) patients (pts) on hormonal therapy (HT) with evidence of biochemical relapse

14612

Background: Imatinib mesylate (Gleevec, G) is a potent inhibitor of the tyrosine kinases and other signaling mediated events. Preclinical models suggest that G inhibits platelet derived growth factor (PDGF) and stem cell factor (SCF) which are important for prostate cancer growth. This trial was designed to evaluate the safety and efficacy of G in PCA pts on HT with stage M0 disease. Methods: Eligible PCA pts included: stage M0 disease with rising PSA levels while on hormonal therapy, no prior chemotherapy. Planned treatment included G 400 mg PO BID given up to a maximum of 12 months. The statistical endpoint for this trial was the% of pts with a ↓ in prostate specific antigen (PSA) ≥ 50% lasting ≥ 4 wks. A 2 stage trial was designed where the study would terminate if the% of pts meeting the endpoint was not convincingly > 30% with 5% chance for error. Pts with a > 50% rise in PSA from baseline were removed from study. Follow-up included monthly toxicities and PSA (specimens frozen/stored until completion of each 3 months of therapy). Results: From 10/1/02–10/11/04, nine pts were enrolled. Pt characteristics included median: age of 67 years (range 52–80), ECOG performance status of 0 (range 0–1), baseline PSA of 29.6 ng/ml (range 2.69–39.52), # prior hormonal manipulations of 3 (1–5). Prior local therapies included: 1 status post (s/p) RP alone, 2 s/p RT alone, 2 s/p neoadjuvant HT plus RP, 2 s/p neoadjuvant HT plus RT. Two pts had no prior local therapy. Two pts had prior salvage RT, 1 had prior palliative RT. Eight of 9 pts evaluable for response and toxicity. One patient never received treatment. None of the pts had a decline 50% decline in PSA level lasting ≥ 4 weeks. Three of 8 pts (38%) had rapid increases in PSA and 4/8 pts (50%) developed metastatic disease after 3 months of therapy. Only one pt completed 12 months of planned therapy. Grade 3/4 toxicities included: fatigue (25%), rash (25%), arthralgias (12.5%), peripheral edema (25%), depression (12.5%), necessitating dose delays and/or discontinuation of G in 4/8 pts (50%). Conclusions: These data suggest significant toxicity and low clinical benefit. Further evaluation of Gleevec in this pt population is not warranted.

No significant financial relationships to disclose.

Traumatic asymmetrical bilateral hip dislocation in an adult

Bilateral hip dislocation occurring as a result of trauma is a rare condition. Simultaneous anterior and posterior traumatic dislocation of both hips is even more unusual. A case is reported of asymmetrical bilateral traumatic hip dislocation without an associated fracture of the pelvis or femur occurring in a young adult with no previous history of hip abnormality or ligamentous laxity. An unusual mechanism for this injury is also described.

Prostate cancer prevention strategies using antiproliferative or differentiating agents

Differentiation or antiproliferative therapies have been most effective in the treatment of promyelocytic leukemia and are being investigated for the treatment of solid tumors including prostate cancer (PCa). Research suggests that these agents may induce terminal differentiation (arrest in G(0)), induce differentiation to a mature cell with cellular functions and a growth pattern similar to nonmalignant cells, or trigger apoptosis. This review focuses on classes of agents under laboratory and clinical evaluation as antiproliferative or differentiating agents: polyamine inhibitors, vitamin D and its analogs, metabolites of vitamin A, the short-chain fatty acid, phenylbutyrate, and nonsteroidal anti-inflammatory agents. Because differentiation therapies offer a reduced toxicity profile and have potential for preventing or slowing cancer progression, they may offer an alternative to chemotherapy for men with advanced PCa, or may be useful as low-toxicity agents given chronically for chemoprevention in men at high risk for PCa. Clinical trials are needed to define the role of these agents in primary and secondary prevention.

Clinical results evaluation of the Girdlestone's procedure after hip arthrography

Background. To date very little work has Bern done on the clinical evaluation of the hip in patients who hale ultimately has a prosthesis removed. This operation, known in English as the Girdlestone procedure, is referred to in Poland as "pendent hip". The present authors have evaluated clinical outcomes of this procedure, taking into account its "rescue" nature.<br /> Material and methods. 22 patients were evaluated, ranging in age from 68 to 87 years, operated in our Clinic between 1979 and 1999 (women: 62,8%; averageage of patientswhen the Girdlestone procedure was performed: 67,2 years). The average observation period after removal of the endoprosthesis was 5,2 years (ranging from 1 to 21 years). The anterolateral approach to the hip joint was used. On each occasion the wound was closed with layer sutures, leaving 4 drains. Postoperative limb traction was maintained for a period lasting form 2 to 4 weeks. The patients were allowed to walk after 4 weeks, with progressively increased load on the operated leg. Clinical evaluated of "pendent hip" was performed using the Harris scale. Shortening of the operated leg (in cm) was also included as well as successful treatment of inflammation (for a period of at least I year) with normalization of the biochemical markers of infection X-ray examinations included periarticular calcification, the remains of cement, and the degree of proximal displacement after surgery on the proximal end of the femur. The patient's subjective evaluation was also included in the overall outcome.<br /> Results. The outcome of surgery was evaluated as good by 12 patients (54,6%), and as satisfactory by 9 (40,9%). These patients did not fully accept the shortening of the limb, the relatively small range of motion, and the need for permanent orthopedic aids (orthopedic shoes to compensate for shortening and elbow cruthes). 1 patient evaluated the outcome as poor due to persistent infection. In 95,5% of the sases the Girdlestone procedure freed the patients of infection and pain, or noticeably reduced it. Only in 1 case did it prove impossible to manage infection completely (4,5%). 18 patients had shortened limbs > 3 cm, while insufficiency of the buttock muscles with positive Trendelenburg and Duchenne signs were the cause of great difficulties and rapid fatigue during walking. The average evaluation of pendent hip using the Harris scale was 58,6 points. In radiological evaluation we often encountered the remains of bone cement. In the case of aseptic loosening this had no impact on the healing process and the late outcome of surgery. Only in I case did it prove impossible to control infection without complete removal od fragments of bone cement. Osteoporosis of the pelvis and proximal end of the femir was found in all patients.<br /> Conclusion. The Girdlestone procedure is a sensible rescue technique both for infected hip prostheses and in situation where reimplantation of the prosthesis is technically impossible.

Evaluation of an ultrabroadband high-gain amplification technique for chirped pulse amplification facilities

Recently, an amplification technique for ultrashort pulses was explored in detail in a theoretical paper by Ross et al. [Opt. Commun. 144, 125 (1997)]. The technique, based on nonlinear optics, is called optical parametric chirped pulse amplification. It has a number of features that, in principle, make it highly attractive. It primarily offers extremely large gains simultaneously with extremely large bandwidths. Additional attractions are virtually no spatial and temporal phase distortion of the amplified pulse, high efficiencies and a low thermal loading, reduced amplified spontaneous emission levels, small optical material lengths, and an inherent simplicity of implementation. We present an evaluation of the technique as a front end amplifier for the ultrashort pulse amplification chain of the Vulcan laser system. Such a device could replace some of the existing amplification in Nd:glass and additionally have a wider effect as a direct replacement of Ti:sapphire regenerative amplifiers on large-scale chirped pulse amplification scale facilities.

In vivo corrosion of 316L stainless-steel hip implants: morphology and elemental compositions of corrosion products

Eleven surgically retrieved stainless steel implants showing varying degrees of surface corrosion were examined to characterize the morphology and composition of corrosion products. The implants were fabricated to the specification AISI316L (Muller) and BS 3531 pt 1 1971-78 (Charnley). They had been in place for 9-21 y (Mean :13 y) and failures were due to aseptic loosening. The morphology and chemical compositions of corrosion products were recorded using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Nine implants had areas of corrosion covering 1-5 cm of the stem, partially or all round. Corrosion existed in layers. The layers consisted either of chromium in association with sulfur, or iron in association with phosphorus. Variable amounts of calcium and chlorine were also present in all layers. Nickel, which makes up 13% of the alloy, was persistently absent. The presence and extent of corrosion was independent of the alloy composition and could not be related to the duration of implantation.

[Results of respiratory muscle training in patients with chronic obstructive lung diseases with a moderately severe course]

The aim of the study was to testify the effectiveness and acceptance of combination of the resistive inspiratory muscle training and the following walking training in 26 stable COPD pts with FEVI%VC about 50%. Measurements of inspiratory (MIP cm H20) and expiratory (MEP cm H20) muscle strength and also spirometric examinations two times before the training and one time after every month of observation were done. During first 3 months of the training inspiratory resistor (Pflex) was used. Everyday 20 s MVV with smaller orifice of Pflex (strength training) and 30 min quiet breathing by medium orifice of Pflex 3 times a week (endurance training) were performed. In first 3 months of experiment 13 patients resigned of it. Other 13 pts (age 64 +/- 11.9. F-4 with medium FEVI%VC = 47.3 +/- 14.5, MIP = -54.1 +/- 11.4, MEP = = 99.8 +/- 40.5) were trained during 3 months. In 11 of them (FEVI%VC = 50.0 +/- 17.3) MIP improved by 33%. Values of other indices did not change at all. After 3 month of resistive training 11 pts (3-F) were qualified to walking training but only 5 (1-F) of them had finished it. After 5 month of exercises their MIP improved by 74% (p < 0.5) and MEP by 50% (p < 0.05). We conclude that our method of resistive breathing with Pflex is effective and well tolerated by stable COPD pts but accepted only by 50% of them. It may be used as the first step before conditioning training. Inspiratory muscle training is not alternative to pharmacological treatment but is valuable supplementation of it.

[Evaluation of respiratory muscle strength in patients with interstitial lung changes based on simultaneous measurement of esophageal and mouth pressure]

A well know good relation between nasal and oesophageal inspiratory pressures exists in healthy and in COPD patients "sniff manoeuvres. Similar results are obtained using "gasp" maneuvers. The aim of the study was to appreciate the usefulness of "gasp" for evaluation of inspiratory muscles strength in ILD patients. 18 ILD patients were examined: group A consisted of 9 pts (8M+IF) aged 35 +/- 8.6 yrs, with static compliance > 70% pred. (mean 98.6 +/- 16.3), group B consisted of 9 pts (6M + 3F) (aged 52 +/- 13.0) with static compliance < 70% pred. (mean 37.2 +/- 12.0), Pmo and Poe (Milic-Emili method) were measured simultaneously during breathing with Pflex device (1.7 mm diameter). Results were stored in a computer for further analysis. In all patients spirometry, plethysmography and maximal inspiratory (MIP) and maximal expiratory (MEP) pressure measurements were performed. Poe and Pmo in group A were nearly the same (8.16 +/- 1.82 vs. 8.35 +/- 2.74 kPa), but in the group B Pmo was lower than Poe (4.81 +/- 1.59 vs. 6.19 +/- 2.03 kPa; p < 0.0005). We conclude that "gasp" - Pmo is a useful method for inspiratory muscle strength measurement only in ILD patients with normal static compliance but in ILD patients with decreased compliance "gasp" - Poe measurement in necessary.

Phase I/pharmacokinetic study of topotecan by 24-hour continuous infusion weekly

Topotecan (SK&F 104864, hycamptamine, NSC 609699) is believed to exert its cytotoxic effects through inhibition of topoisomerase I, the activity of which recovers rapidly on removal of the drug in vitro. In vivo studies show that the activity of topotecan is schedule dependent, favoring repeated doses. Early human studies showed that topotecan (the active lactone) had a short half-life in plasma. To prolong drug exposure, we administered topotecan as a 24-h i.v. infusion and repeated it weekly. We treated 32 patients with doses of 1.0-2.0 mg/m2. Median performance status was 1, and all but four patients had received prior chemotherapy. Dose-limiting neutropenia occurred at doses > or = 1.75 mg/m2; nadirs were observed after 1-3 doses. The recommended phase II dose is 1.5 mg/m2/week. One patient with metastatic colon cancer had a partial response. Both plasma topotecan (lactone) and total topotecan (measured by converting the hydroxyacid form to the lactone by acidification of the sample) were measured by high-performance liquid chromatography in 21 patients. During infusion, mean topotecan plasma steady-state concentrations ranged from 4.7-11.4 nM. Plasma elimination was best fit to a one-compartment model with a mean t1/2 of 3.5 h. The mean total body clearance was 388 ml/min/m2. Concentrations of the inactive form approximated those of the lactone throughout. No evidence for dose-dependent pharmacokinetics was observed in this dose range. Pharmacodynamic analysis, using the sigmoid Emax model, revealed that the pharmacokinetic parameters of both lactone and total drug were positively correlated with bone marrow toxicity. Total drug steady-state plasma concentration provided a good estimate of neutropenia, suggesting a simple, easily monitored, pharmacokinetic parameter for adaptive dosing using this schedule. Phase II evaluation of this weekly schedule is indicated in solid tumors.

Phase I/pharmacokinetic/biochemical study of the nitroimadazole hypoxic cell sensitiser SR2508 (etanidazole) in combination with cyclophosphamide

SR2508 sensitises certain hypoxic tumor cells in vitro and in vivo to the cytotoxic action of radiation and alkylating agents. The mechanism of sensitisation may derive in part from depletion of glutathione (GSH) and possibly inhibition of GSH-dependent enzymes in target cells. We treated 46 evaluable patients with cyclophosphamide 750-1000 mg m-2 followed by SR2508 at eight dose levels ranging from 2.5 to 15.0 g m-2. Each patient received SR2508 as a single agent initially, followed a week later by the combination of cyclophosphamide and SR2508. Initially, myelosuppression was the major toxicity; potentiation of cyclophosphamide-induced leukopenia by SR2508 required a dose reduction of cyclophosphamide to 750 mg m-2 at SR2508 doses above 7.2 g m-2. At doses above 9.4 g m-2 an acute syndrome of muscle pains and painful paresthesias of the extremities lasting 12-24 h was observed to occur with increasing severity. This side-effect was intolerable in two of three patients treated at 15.0 g m-2. The only other reproducible side-effect was nausea and vomiting which was controllable with antiemetics. Plasma and urine SR2508 concentrations were measured by HPLC in 45 patients. Plasma elimination curves fit a 2-compartment model. The mean terminal half-life at each dose level ranged from 5.1-5.8 h. The mean area under the plasma concentration-time curve was linearly related to dose, and mean total body clearance ranged from 46.6-94.0 ml-1 min-1 m-2; renal clearance accounted for 65.7-79.3%. Pretreatment with cyclophosphamide did not influence the kinetics of SR2508 in individual patients. Examination of the glutathione content of peripheral mononuclear cells and tumour samples showed that depletion to below 50% of control occurred in the majority of patients. GSH transferase inhibition occurred with a similar time-course, but to a lesser extent. These data suggest that the further evaluation of this regimen should be conducted with SR2508 administration preceding that of cyclophosphamide and that its evaluation in cyclophosphamide-sensitive tumours is warranted.

Research considerations. Geropsychiatry unit evaluation

The specialized psychiatric units for geriatric patients are believed to be effective, yet no studies could be found documenting this. A method of evaluating the effectiveness of a geropsychiatric program is to measure changes in the cognitive and functional status of its patients. This study supports the hypothesis that there would be an improvement in the geropsychiatric patients' cognitive and functional assessment scores by discharge and after hospitalization.

Preservation of immune effector cell function following administration of a dose-intense 5-fluorouracil-chemotherapy regimen

In a phase II clinical trial of 5-fluorouracil (5FU) plus N-(phosphonacetyl)-L-aspartate (PALA) therapy administration, a number of slowly developing clinical responses were observed. Because of this, a variety of immune parameters were sequentially studied in 21 patients on this trial. Of the 21 patients studied, 20 provided sufficient samples to compare baseline with subsequent values, 10 of the 20 patients responded to treatment. Responders and non-responders did not differ in any studied parameter at baseline. After 2 months of therapy, non-specific monocyte cytotoxicity (NSMC), antibody-dependent monocyte cytotoxicity (ADMC) and natural killer (NK) activity were higher in the entire study population, but these increases were not statistically significant. When responders and non-responders were evaluated separately, it was apparent that the trend was due solely to the changes observed in the responding patient population. When mean lysis values for each patient group were determined for each studied time point, it was possible to generate a mean area under the cytotoxicity/time curve (AUC) for each studied parameter. NSMC and ADMC did not differ in responders and non-responders. However, NK activity was significantly greater by mean AUC analysis (P = 0.006) in the responding group; NK activity was maintained in the responders, but decreased in non-responders. When lymphocyte and monocyte expression of the surface markers beta 2-microglobulin, HLA-DR, CD56, HNK-1, CD16 and interleukin-2 receptor were evaluated, there were no differences among responders and non-responders at baseline by mean AUC analysis or when comparing baseline with non-baseline values. It is concluded that although baseline immunological characteristics do not identify patients who are likely to respond to weekly 5FU and PALA, treatment is not associated with deleterious effects on the immune effector function parameters evaluated in this study, there being no effects on expression of a variety of associated cell-surface molecules.

Phase I and pharmacokinetic study of the novel platinum analogue CI-973 on a 5-daily dose schedule

CI-973, a platinum(II) derivative with a 2-methyl-1,4-butanediamine carrier ligand, has activity in cisplatin-resistant tumor models in vitro and in vivo. In a Phase I pharmacokinetic study, 31 patients were treated with CI-973 (24 to 50 mg/m2/day for 5 days; 28-day cycles) given i.v. over 30 min without routine antiemetic prophylaxis or hydration. Of the 29 patients evaluable for maximum tolerated dose determination, most had a performance status of 0 or 1, and most had received prior chemotherapy. Neutropenia was dose limiting at 40 and 50 mg/m2/day. Recovery from neutropenia was generally rapid with nadir counts and recovery usually occurring by Days 15 and 22, respectively. Drug-associated thrombocytopenia was uncommon and never severe, even in patients with Grade 4 neutropenia. Anemia was common, but did not appear dose related. Drug-related nausea and vomiting and changes in renal function were relatively infrequent and mild. No clinically evident ototoxicity was reported, although changes in audiograms were noted in several patients. CI-973 concentrations were measured in plasma ultrafiltrate and urine by high-pressure liquid chromatography. The harmonic mean terminal half-life was 2.0 h. The mean CI-973 renal and nonrenal clearance values were 42.3 and 37.4 ml/min/m2, respectively. The mean recovery of CI-973 in urine was 53% of the administered dose. The mean ratio of CI-973 renal clearance to creatinine clearance was 0.92. Total clearance correlated with creatinine clearance (r2 = 0.63). A relationship between toxicity, expressed as the percentage of reduction in absolute granulocyte count, and area under the CI-973 plasma concentration-time curve was found in a subgroup of "good-risk" patients. This relationship, described well by a sigmoidal Emax pharmacodynamic model, did not hold for patients with extensive prior therapy or poor performance status. A model for toxicity prediction based on dose and creatinine clearance has been derived and will be validated in future studies. The recommended Phase II dose of CI-973 is 30 mg/m2/day for 5 days.

Phase II trial of PALA in combination with 5-fluorouracil in advanced pancreatic cancer

Phosphonacetyl-L-aspartate (PALA), in inhibitor of aspartate transcarbamylase that depletes uridine nucleotide pools, selectively potentiates the antitumor activity of 5-fluorouracil (5-FU) in preclinical models. Due to the promising results we obtained using PALA/5-FU in colorectal cancer, we performed a phase II trial in patients presenting with advanced pancreatic cancer. PALA was given intravenously at 250 mg/m2 on day 1, followed 24 h later by 2,600 mg/m2 5-FU given by 24-h infusion. Treatments were repeated weekly. A total of 41 patients who had not previously undergone chemotherapy were entered in the trial; of these, 35 were evaluable for response. Toxicity was generally mild to moderate; neurotoxicity (13/35) and diarrhea (8/35) predominated. Among the 35 patients, 1 achieved a complete response and 4, a partial remission, for an overall response rate of 14%. The median survival was 5.1 months. Pretreatment with PALA alone was not sufficient to enhance the activity of 5-FU in pancreatic cancer.

Phase II study of weekly 5-fluorouracil, cisplatin and vinblastine in advanced non-small cell lung cancer

The scheduling of chemotherapeutic agents may be important in optimising their antitumour actions. This has been explored in non-Hodgkin lymphoma, osteogenic sarcoma and bladder cancer with improved results using intensive, weekly dosing schemas. We began a phase II study of cisplatin, 5-fluorouracil and vinblastine in non-small cell lung cancer (NSCLC) on a weekly schedule. 38 patients with advanced or metastatic NSCLC were entered; 32 are evaluable for response. 11 patients were treated with 5-fluorouracil 1.5 g/m2 and vinblastine 4 mg/m2 by 24-h continuous infusion, and cisplatin 30 mg/m2 over 30 min, 6-8 h after the start of the infusion. Because of prohibitive myelotoxicity, the next 27 patients received 5-fluorouracil 1.2 g/m2 and vinblastine 3 mg/m2. None had had prior chemotherapy while 6 had had previous radiation therapy. Myelosuppression was the predominant toxic effect. Other side-effects included neuropathy, diarrhoea, mucositis, nausea and vomiting. 32 patients are evaluable for response: there have been 14 partial remissions (44%). Responses have occurred chiefly in lung and lymph nodes. The median survival on this study is 7 months, and responders did not live longer than non-responders. While this regimen is well tolerated by the majority of patients and has a response rate comparable to other active regimens identified in single institution studies, survival does not appear to be enhanced. We conclude that the schedule manipulation described here does not enhance the therapeutic index of these drugs in NSCLC.

Phase I trial of fluorouracil modulation by N-phosphonacetyl-L-aspartate and 6-methylmercaptopurine riboside: optimization of 6-methylmercaptopurine riboside dose and schedule through biochemical analysis of sequential tumor biopsy specimens

Preclinical and clinical studies demonstrate that the selective antitumor activity of fluorouracil (5-FU) is enhanced by agents which perturb certain intracellular nucleotide pools. We previously demonstrated that the combination of N-phosphonacetyl-L-aspartate (PALA), which depletes pyrimidine nucleotide pools, and 5-FU yielded a 43% response rate among 37 assessable patients with colorectal carcinoma. In preclinical tumor models, 6-methylmercaptopurine riboside (MMPR), an inhibitor of purine synthesis, elevates phosphoribosylpyrophosphate (PRPP) pools and promotes the anabolism of 5-FU to fluorinated nucleotides. In vivo, the addition of MMPR enhances the therapeutic efficacy of PALA-5-FU. In a phase I trial, we sought to determine the optimal dose and schedule of MMPR in combination with PALA (250 mg/m2 on day 1) and 5-FU (1300 mg/m2 by 24-hour infusion on day 2). MMPR (75-225 mg/m2) was given intravenously on day 1 to 27 patients with solid tumors (15 colorectal, seven breast, five other). Toxic effects were mild to moderate and included leukopenia, mucositis, nausea, or rash. Two of seven patients given MMPR at 225 mg/m2 had grade 3 diarrhea. PRPP was measured using a [14C]orotic acid 14CO2 release assay in tumor biopsy specimens obtained before and 12 hours and 24 hours after MMPR doses were given to 20 patients. The addition of MMPR elevated PRPP pools in human solid tumors. At 12 hours after treatment, two (50%) of four patients showed a twofold or greater elevation of PRPP at the MMPR dose level of 75 mg/m2; a similar elevation was observed in five (71%) of seven patients given 150 mg/m2 MMPR and in three (43%) of seven patients given 225 mg/m2 MMPR. At 24 hours after treatment, results for the respective dose levels of MMPR were two (33%) of six patients, one (20%) of five patients, and four (57%) of seven patients. Administration of the two highest MMPR dose levels appeared to result in a greater increase in tumor PRPP levels. However, toxicity was greater at the 225 mg/m2 dose level; therefore, the 150 mg/m2 dose level was favored. Tumor levels of PRPP decreased between 12 hours and 24 hours in nine (56%) of 16 patients. This time course indicates that MMPR should be administered at the beginning of the 24-hour infusion of 5-FU.

Pharmacokinetic study of trimetrexate in combination with cisplatin

The addition of the antifol methotrexate to cisplatin (DDP) produces supraadditive antitumor effects in preclinical studies, but in the clinic this combination of two nephrotoxic drugs is limited by excessive toxicity. Trimetrexate (TMTX) is a second generation antifol with predominantly nonrenal elimination and antitumor activity superior to that of methotrexate in preclinical models. In early clinical trials TMTX demonstrated promising activity in non-small cell lung cancer, and nephrotoxicity was rare. We performed a Phase I clinical and pharmacological study of TMTX (escalating doses) in combination with DDP (20 mg/m2), both administered i.v. for 5 consecutive days, every 4 wk. The pharmacokinetics of TMTX was determined in 15 patients after administration of the single agent (baseline study) and following the Day 1 and Day 5 doses in the TMTX-DDP combination. The recommended Phase II single-agent dose of TMTX on this schedule, 8 mg/m2, did not produce excessive toxicity when given concurrently with DDP. Significant drug-related nephrotoxicity was not observed, even in patients receiving multiple courses of TMTX-DDP. The mean renal clearance of TMTX increased 1.4-fold and 2.8-fold over baseline on Days 1 and 5, respectively, of TMTX-DDP. Urinary flow was similarly greater on days of TMTX-DDP treatment. The nonrenal clearance of TMTX was unaffected by concurrent DDP. The steady-state volume of distribution, Vdss, and terminal elimination half-life were significantly greater on Day 5 of TMTX-DDP compared to baseline. The plasma protein-binding of TMTX in vitro was not altered by DDP, and the disappearance of ultrafilterable DDP from normal plasma in vitro was unchanged by TMTX. Although a protein-binding interaction of TMTX and DDP was not detected in normal plasma in vitro, the changes in renal clearance, Vdss, and the terminal half-life were consistent with a greater fraction of unbound TMTX in plasma following Day 5 of TMTX-DDP. Effects of DDP on the binding of TMTX to extravascular tissue components, or on the renal handling of TMTX, cannot be excluded. The increase in TMTX renal clearance correlated with increased urinary flow, which may improve the therapeutic index of TMTX as both an antineoplastic and antiparasitic agent.

Phase II study of amonafide (nafidamide, NSC 308847) in advanced colorectal cancer

Amonafide, a benzisoquinoline-1,3-dione with anti-tumor activity in preclinical screens, was administered to patients with recurrent or metastatic bidimensionally measurable colorectal cancer. Fourteen patients with no prior chemotherapy for advanced disease, performance status 0-1, and normal bone marrow, renal, and hepatic function were entered. Amonafide 300 mg/m2 was administered intravenously over 1 hour daily for five consecutive days; courses were repeated every three weeks. The major side effect was neutropenia: Grade 3 or 4 toxicity occurred in 5/14 patients. Other toxicities included nausea and vomiting, flulike symptoms, fever, rash and alopecia. Three patients had stable disease, but there were no responses observed. Amonafide at this dose and schedule has no activity in the treatment of colorectal cancer.

Phase II study of biochemical modulation of fluorouracil by low-dose PALA in patients with colorectal cancer

Higher response rates in colorectal cancer have been observed with regimens that increase the cytotoxicity of fluorouracil (5-FU) by altering the biochemical milieu at its site(s) of action. Phosphonacetyl-L-aspartate (PALA), which inhibits aspartate transcarbamylase and depletes uridine nucleotide pools in vitro and in vivo, selectively potentiates the antitumor activity of 5-FU in preclinical models. In a phase I/II study in patients with advanced colorectal cancer, PALA 250 mg/m2 was given on day 1, followed 24 hours later by 5-FU 2,600 mg/m2 by 24-hour infusion repeated weekly. Through the use of subcutaneous ports and portable infusion pumps, all patients were treated outside the hospital setting. Thirty-nine patients without prior chemotherapy received 884 courses of treatment. The primary site was colon in 31, rectum in eight. Toxicity was generally mild to moderate except among four patients who were escalated to 5-FU 3,250 mg/m2: two developed severe gastrointestinal toxicity and myelosuppression. Among the remaining 35 patients, gastrointestinal and neurologic toxicities predominated, but usually did not develop until the third or fourth month of treatment. Two patients were inevaluable for response. Among the 37 evaluable patients there were three complete and 13 partial remissions for a total response rate of 43% (95% confidence interval [Cl], 27% to 59%). The median duration of response was 5 months (range, 1.5 to 15 months). The projected mean survival is in excess of 17 months. This high response rate is comparable to the best results obtained with other means of modulation of 5-FU. Demonstration of a survival benefit will require larger phase III studies.