Detailed Sub-study Analysis of the SECRAB Trial: Quality of Life, Cosmesis and Chemotherapy Dose Intensity.

AIMS: SECRAB was a prospective, open-label, multicentre, randomised phase III trial comparing synchronous to sequential chemoradiotherapy (CRT). Conducted in 48 UK centres, it recruited 2297 patients (1150 synchronous and 1146 sequential) between 2 July 1998 and 25 March 2004. SECRAB reported a positive therapeutic benefit of using adjuvant synchronous CRT in the management of breast cancer; 10-year local recurrence rates reduced from 7.1% to 4.6% (P = 0.012). The greatest benefit was seen in patients treated with anthracycline-cyclophosphamide, methotrexate, 5-fluorouracil (CMF) rather than CMF. The aim of its sub-studies reported here was to assess whether quality of life (QoL), cosmesis or chemotherapy dose intensity differed between the two CRT regimens. MATERIALS AND METHODS: The QoL sub-study used EORTC QLQ-C30, EORTC QLQ-BR23 and the Women's Health Questionnaire. Cosmesis was assessed: (i) by the treating clinician, (ii) by a validated independent consensus scoring method and (iii) from the patients' perspective by analysing four cosmesis-related QoL questions within the QLQ-BR23. Chemotherapy doses were captured from pharmacy records. The sub-studies were not formally powered; rather, the aim was that at least 300 patients (150 in each arm) were recruited and differences in QoL, cosmesis and dose intensity of chemotherapy assessed. The analysis, therefore, is exploratory in nature. RESULTS: No differences were observed in the change from baseline in QoL between the two arms assessed up to 2 years post-surgery (Global Health Status: -0.05; 95% confidence interval -2.16, 2.06; P = 0.963). No differences in cosmesis were observed (via independent and patient assessment) up to 5 years post-surgery. The percentage of patients receiving the optimal course-delivered dose intensity (≥85%) was not significantly different between the arms (synchronous 88% versus sequential 90%; P = 0.503). CONCLUSIONS: Synchronous CRT is tolerable, deliverable and significantly more effective than sequential, with no serious disadvantages identified when assessing 2-year QoL or 5-year cosmetic differences.

Breast Cancer Index and prediction of benefit from extended endocrine therapy in breast cancer patients treated in the Adjuvant Tamoxifen-To Offer More? (aTTom) trial.

BACKGROUND: Extending the duration of adjuvant endocrine therapy reduces the risk of recurrence in a subset of women with early-stage hormone receptor-positive (HR+) breast cancer. Validated predictive biomarkers of endocrine response could significantly improve patient selection for extended therapy. Breast cancer index (BCI) [HOXB13/IL17BR ratio (H/I)] was evaluated for its ability to predict benefit from extended endocrine therapy in patients previously randomized in the Adjuvant Tamoxifen-To Offer More? (aTTom) trial. PATIENTS AND METHODS: Trans-aTTom is a multi-institutional, prospective-retrospective study in patients with available formalin-fixed paraffin-embedded primary tumor blocks. BCI testing and central determination of estrogen receptor (ER) and progesterone receptor (PR) status by immunohistochemistry were carried out blinded to clinical outcome. Survival endpoints were evaluated using Kaplan-Meier analysis and Cox regression with recurrence-free interval (RFI) as the primary endpoint. Interaction between extended endocrine therapy and BCI (H/I) was assessed using the likelihood ratio test. RESULTS: Of 583 HR+, N+ patients analyzed, 49% classified as BCI (H/I)-High derived a significant benefit from 10 versus 5 years of tamoxifen treatment [hazard ratio (HR): 0.35; 95% confidence interval (CI) 0.15-0.86; 10.2% absolute risk reduction based on RFI, P = 0.027]. BCI (H/I)-low patients showed no significant benefit from extended endocrine therapy (HR: 1.07; 95% CI 0.69-1.65; -0.2% absolute risk reduction; P = 0.768). Continuous BCI (H/I) levels predicted the magnitude of benefit from extended tamoxifen, whereas centralized ER and PR did not. Interaction between extended tamoxifen treatment and BCI (H/I) was statistically significant (P = 0.012), adjusting for clinicopathological factors. CONCLUSION: BCI by high H/I expression was predictive of endocrine response and identified a subset of HR+, N+ patients with significant benefit from 10 versus 5 years of tamoxifen therapy. These data provide further validation, consistent with previous MA.17 data, establishing level 1B evidence for BCI as a predictive biomarker of benefit from extended endocrine therapy. TRIAL REGISTRATION: ISRCTN17222211; NCT00003678.

Comparison of quadrant-specific breast cancer incidence trends in the United States and England between 1975 and 2013.

BACKGROUND: UK breast cancer incidence rates suggest that upper outer quadrant (UOQ) cancers have risen disproportionately compared with other areas over time. We aimed to provide a comparison of the trend in quadrant-specific breast cancer incidence between the United States (US) and England, and determine whether a disproportionate UOQ increase is present. METHODS: Surveillance Epidemiology and End Results (SEER) cancer registry data were obtained on 630,007 female breast cancers from 1975 to 2013. English cancer registry data were obtained on 1,121,134 female breast cancers from 1979 to 2013. Temporal incidence changes were analysed using negative binomial regression. Interaction terms determined whether incidence changes were similar between sites. RESULTS: English breast cancer incidence in the UOQ rose significantly from 13% to 28% from 1979 to 2013 whereas no significant increase was observed among SEER data. The significant interaction between quadrant and year of diagnosis (p<0.001) in both SEER and English data indicates that breast cancer incidence in each quadrant changed at a different rate. Incidence in the UOQ rose disproportionately compared to the nipple (SEER IRR=0.81, p<0.001; England IRR=0.78, p<0.001) and axillary tail (SEER IRR=0.87, p=0.018; England IRR=0.69, p<0.001) in both SEER and England. In addition, incidence rose disproportionately in the UOQ compared to non-site-specific tumours in England (Overlapping lesions IRR=0.81, p=0.002; NOS IRR=0.78, p<0.001). The proportion of non-site-specific tumours was substantially higher in England than SEER throughout the study period (62% in England; 39% in SEER). CONCLUSIONS: Breast cancer incidence in the UOQ increased disproportionately compared to non-site-specific tumours in England but not in SEER, likely due to the decrease in non-site-specific tumours observed in England over time. There may be real differences in incidence between the two countries, possibly due to differences in aetiology, but is much more likely to be an artefact of changing data collection methods and improvements in site coding in either country.

Time dependence of biomarkers: non-proportional effects of immunohistochemical panels predicting relapse risk in early breast cancer.

BACKGROUND: We investigated the impact of follow-up duration to determine whether two immunohistochemical prognostic panels, IHC4 and Mammostrat, provide information on the risk of early or late distant recurrence using the Edinburgh Breast Conservation Series and the Tamoxifen vs Exemestane Adjuvant Multinational (TEAM) trial. METHODS: The multivariable fractional polynomial time (MFPT) algorithm was used to determine which variables had possible non-proportional effects. The performance of the scores was assessed at various lengths of follow-up and Cox regression modelling was performed over the intervals of 0-5 years and >5 years. RESULTS: We observed a strong time dependence of both the IHC4 and Mammostrat scores, with their effects decreasing over time. In the first 5 years of follow-up only, the addition of both scores to clinical factors provided statistically significant information (P<0.05), with increases in R(2) between 5 and 6% and increases in D-statistic between 0.16 and 0.21. CONCLUSIONS: Our analyses confirm that the IHC4 and Mammostrat scores are strong prognostic factors for time to distant recurrence but this is restricted to the first 5 years after diagnosis. This provides evidence for their combined use to predict early recurrence events in order to select those patients who may/will benefit from adjuvant chemotherapy.

Do type 1 receptor tyrosine kinases inform treatment choice? A prospectively planned analysis of the TEAM trial.

BACKGROUND: Epidermal growth factor receptors contribute to breast cancer relapse during endocrine therapy. Substitution of aromatase inhibitors (AIs) may improve outcomes in HER-positive cancers. METHODS: Tissue microarrays were constructed. Quantitative analysis of HER1, HER2, and HER3 was performed. Data were analysed relative to disease-free survival and treatment using outcomes at 2.75 and 6.5 years. RESULTS: Among 4541 eligible samples, 4225 (93%) had complete HER1-3 data. Overall, 5% were HER1-positive, 13% HER2-positive, and 21% HER3-positive; 32% (n=1351) overexpressed at least one HER receptor. In the HER1-3-negative subgroup, the hazard ratio (HR) for upfront exemestane vs tamoxifen at 2.75 years was 0.67 (95% confidence interval (CI), 0.52-0.87), in the HER1-3-positive subgroup, the HR was 1.15 (95% CI, 0.85-1.56). A prospectively planned treatment-by-marker analysis demonstrated a significant interaction between HER1-3 and treatment at 2.75 years (HR=0.58; 95% CI, 0.39-0.87; P=0.008), as confirmed by multivariate regression analysis adjusting for prognostic factors (HR=0.55; 95% CI, 0.36-0.85; P=0.005). This effect was time dependent. CONCLUSION: In the 2.75 years prior to switching patients initially treated with tamoxifen to exemestane, a significant treatment-by-marker effect exists between AI/tamoxifen treatment and HER1-3 expression, suggesting HER expression could be used to select appropriate endocrine treatment at diagnosis to prevent or delay early relapses.

Adjuvant epirubicin followed by cyclophosphamide, methotrexate and fluorouracil (CMF) vs CMF in early breast cancer: results with over 7 years median follow-up from the randomised phase III NEAT/BR9601 trials.

BACKGROUND: The National Epirubicin Adjuvant Trial (NEAT) and BR9601 trials tested the benefit of epirubicin when added to cyclophosphamide, methotrexate and 5-fluorouracil (E-CMF) compared with standard CMF in adjuvant chemotherapy for women with early breast cancer. This report details longer follow-up with interesting additional time-dependent analyses. METHODS: National Epirubicin Adjuvant Trial used epirubicin (E) 3-weekly for four cycles followed by classical (c) CMF for four cycles (E-CMF) compared with cCMF for six cycles. BR9601 used E 3-weekly for four cycles followed by CMF 3-weekly for four cycles, compared with CMF 3-weekly for eight cycles. RESULTS: In all, 2391 eligible patients were randomised and with a median 7.4-year follow-up, E-CMF confirmed a significant benefit over CMF in both relapse-free survival (RFS) (78% vs 71% 5 years RFS, respectively, hazard ratio (HR)=0.75 (95% CI: 0.65-0.86), P<0.0001) and overall survival (OS) (84% vs 78% 5 years OS, respectively, HR=0.76 (95% CI: 0.65-0.89), P=0.0007). Interaction of treatment effect and prognostic factors was demonstrated for duplication of chromosome 17 centromeric enumeration (Ch17CEP) as previously reported. Poor prognostic factors at diagnosis (ER and PR negative and HER2 positive) showed time-dependent annual hazard rates for RFS and OS. In univariate analysis, these factors demonstrated more favourable HRs for RFS after 5 years. Treatment effects also suggested a differential benefit for E-CMF within the first 5 years for poor prognosis tumours. CONCLUSION: Longer follow-up has confirmed E-CMF as significantly superior to CMF for all patients. Ch17CEP duplication was the only biomarker that demonstrated significant treatment interaction. Standard poor prognostic factors at diagnosis were time-dependent, and after 5 years disease-free, poor prognosis patients demonstrated favourable HRs for survival.

Physical activity and breast cancer outcome: a brief review of evidence, current practice and future direction.

There have been several publications of large scale studies with long-term follow up addressing the role of physical activity in the management of breast cancer. Of the twelve studies specifically addressing the effect of physical activity on breast cancer survival, eight showed a statistically significant 50% risk reduction in breast cancer mortality in women who engaged in moderate intensity physical activity before and after their diagnosis of breast cancer. Four smaller studies demonstrated no benefit. Almost all of these observational studies predominantly involved white, professional women from North America and Europe. The positive effects of physical activity were seen for all stages of cancer, with the greatest benefit in steroid receptor positive breast tumours. These studies relied on self-reported questionnaires for recording the levels of physical activity. Despite including thousands of patients, published studies offer no data related to the optimum type, duration and timing of physical activity. Only a few studies provided objective data on physical activity, cardio-respiratory and general fitness. Thus, potential role of physical activity in the management of breast cancer remains far from established. If the beneficial effect of physical activity as demonstrated in the observational studies can be replicated in robust, well designed and well-executed prospective randomised controlled trials, this would provide a tremendous opportunity to enhance adjuvant treatment of breast cancer. By adding physical activity to the spectrum of adjuvant therapies offered to women survival from breast cancer may be enhanced.

Systematic review of aromatase inhibitors in the first-line treatment for hormone sensitive advanced or metastatic breast cancer.

To undertake a systematic review of three first-line treatments (letrozole, anastrozole and exemestane) for hormone sensitive advanced or metastatic breast cancer (MBC) in post-menopausal women. We searched six databases from inception up to January 2009 for relevant trials regardless of language or publication status. Randomised controlled clinical trials assessing the safety and efficacy of first-line AIs for post-menopausal women with hormone receptor-positive (HR+, i.e. ER+ and/or PgR+) with or without ErbB2 (HER2)-positive MBC, who have not received prior therapy for advanced or metastatic disease were included. Where meta-analysis using direct or indirect comparisons was considered unsuitable for some or all of the data, we employed a narrative synthesis method. Four studies (25 papers) met the inclusion criteria. From the available evidence, it was possible to directly compare the three AIs with tamoxifen. In addition, by using a network meta-analysis it was possible to compare the three AIs with each other. Based on direct evidence, letrozole seemed to be significantly better than tamoxifen in terms of time-to-progression (TTP) (HR = 0.70 (95% CI: 0.60, 0.82)), objective response rate (RR = 0.65 (95% CI: 0.52, 0.82)) and quality-adjusted time without symptoms or toxicity (Q-Twist difference = 1.5; P < 0.001). Exemestane seemed significantly superior to tamoxifen in terms of objective response rate (RR = 0.68 (95% CI: 0.53, 0.89)). Anastrozole seemed significantly superior to tamoxifen in terms of TTP in one trial (HR = 1.42 (95% CI: 1.15, NR)), but not in the other (HR = 1.01 (95% CI: 0.87, NR)). In terms of adverse events, no significant differences were found between letrozole and tamoxifen. Tamoxifen was associated with significantly more serious adverse events in comparison with exemestane (OR = 0.61 (95% CI: 0.38, 0.97)); while exemestane was associated with significantly more arthralgia in comparison with tamoxifen (OR = 2.33 (95% CI: 1.07, 5.11)). Anastrozole was associated with significantly more total adverse events (OR = 1.04 (95% CI: 1.00, 1.09)) and hot flushes (OR = 1.39 (95% CI: 1.03, 1.89)) in comparison with tamoxifen in one trial; however, the other trial showed no significant differences in adverse events between anastrozole and tamoxifen. The indirect comparison of AIs with each other in women with post-menopausal, hormone sensitive advanced or MBC showed that letrozole and exemestane were better in terms of objective response rate than anastrozole; while the more clinically relevant outcomes overall survival (OS) and progression-free survival (PFS) showed no significant differences between AIs. OS and PFS showed no significant differences between AIs and hence based on these results a class effect for all AIs is possible. However, these results are based on indirect comparisons and a network analysis for which the basic assumptions of homogeneity, similarity and consistency were not fulfilled. Therefore, despite the fact that these are the best available data, the results need to be interpreted with appropriate caution. Head-to-head comparisons between letrozole, anastrozole and exemestane in the first-line MBC setting are warranted.

Variations in locoregional therapy in postmenopausal patients with early breast cancer treated in different countries.

BACKGROUND: The Tamoxifen and Exemestane Adjuvant Multinational (TEAM) trial is an international randomized trial evaluating the efficacy and safety of exemestane, alone or following tamoxifen. The large number of patients already recruited offered the opportunity to explore locoregional treatment practices between countries. METHODS: Patients were enrolled in Belgium, France, Germany, Greece, Ireland, Japan, the Netherlands, the UK and the USA. The core protocol had minor differences in eligibility criteria between countries, reflecting variations in national guidelines and practice regarding adjuvant endocrine therapy. RESULTS: Between 2001 and 2006, 9779 patients of mean(s.d.) age 64(9) years were randomized. Some 58.4 per cent had T1 tumours (range between countries 36.8-75.9 per cent; P < 0.001) and 47.3 per cent were axillary node positive (range 25.9-84.6 per cent; P < 0.001). Independent factors for type of breast surgery were country, age, tumour status and calendar year of surgery. After breast-conserving surgery, radiotherapy was given to 93.2 per cent of patients, 86.0 per cent in the USA and 100 per cent in France. Axillary lymph node dissection was performed in 82.0 (range 74.6-99.1) per cent. CONCLUSION: Despite international consensus guidelines, wide global variations were observed in treatment practices of early breast cancer. There should be further efforts to optimize locoregional treatment for breast cancer worldwide.

Role of tyrosine kinase inhibitors in lung cancer.

Protein tyrosine kinases are enzymes which catalyze the phosphorylation of tyrosine residues and activate a downstream cascade of cellular signalling pathways which regulate cell proliferation, differentiation and apoptosis and a wide variety of cellular functions. Clinical developments over the past decade have identified several novel therapeutic agents which inhibit tyrosine kinase activity, either by direct receptor inhibition or indirect inhibition of tyrosine kinase controlled pathways. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKI), such as gefitinib and erlotinib have been studied extensively in patients with refractory non-small cell lung cancer (NSCLC). Early studies with gefitinib showed undoubted clinical activity but failed to show a survival benefit, whereas studies with erlotinib showed a small but statistically significant benefit in overall survival. Subsequent studies explored the possibility of synergistic activity between targeted agents (gefitinib or erlotinib) and conventional chemotherapy drugs reporting disappointing results. Clinical trial results with gefitinib and erlotinib, either as monotherapy or in combination with chemotherapy, have failed to match the encouraging results noted in the pre-clinical setting. It is now increasingly recognised that clinical exploration of molecular targeted agents may not conform well to traditional phase I/II/III drug trial designs. Therapeutic responses may be limited to a small subpopulation of patients, therefore diluting the overall therapeutic effect. Hypothesising a genetic basis for the heterogeneity in trial results, biomarkers (such as EGFR gene mutation analysis, EGFR protein expression, and increased EGFR gene copy number) have been studied with a view to identifying a target population most likely to benefit from these drugs. Future clinical trials with targeted agents need to be carefully designed to incorporate correlative translational research elements that will allow selection of appropriate treatment strategies for individual patients. For assessment of phase III trial results in advanced disease, progression free survival may serve as a more appropriate end-point than response rate in an adequately designed trial in the appropriately selected population, although there should be no substitute for the overall survival and quality of life end points. The role of EFGR TKI in NSCLC will be discussed in detail and data from these studies will be used to illustrate the challenges in designing clinical trials and interpreting outcomes.

NEAT: National Epirubicin Adjuvant Trial--toxicity, delivered dose intensity and quality of life.

The NEAT trial reported considerable benefit for ECMF (epirubicin followed by cyclophosphamide, methotrexate and 5-fluorouracil) of 28% for relapse-free survival (RFS) and 30% for overall survival (OS), when compared with classical CMF in early breast cancer. To assess tolerability, toxicity, dose intensity and quality of life (QoL) analyses were undertaken. All 2021 eligible patients had common toxicity criteria (CTC), delivered chemotherapy and supportive treatments details and long-term morbidities recorded. The QoL substudy used multiple validated measures. ECMF produced low CTC scores, although higher than CMF for nausea, vomiting, alopecia, constipation, stomatitis (P<0.001), infection (P=0.001) and fatigue (P=0.03). Supportive treatments required, however, were similar across randomised treatments. On-treatment deaths were more common with CMF (13) than ECMF(5). Optimal course-delivered dose intensity (CDDI > or =85%) was received more often by ECMF patients (83 vs 76%: P=0.0002), and was associated with better RFS (P=0.0006). QoL over 2 years was equivalent across treatments, despite minimally worse side effects for ECMF during treatment. ECMF benefit spanned all levels of toxicity, CDDI and QoL. There are no reported acute myeloid leukaemias or cardiac dysfunctions. ECMF is tolerable, deliverable, and significantly more effective than CMF, with no serious long-term toxicity or QoL detriment.

A phase II clinical trial of gemcitabine and split dose cisplatin in advanced non-small cell lung cancer in an outpatient setting.

In response to increasing pressure on inpatient services and a meta-analysis indicating that cisplatin (C) is superior to carboplatin, we report a phase II trial of gemcitabine (G) and split-dose C in advanced non-small cell lung cancer (NSCLC) in an outpatient setting. Patients with stage IIIB/IV NSCLC received: G/C 1250/40 mg/m(2); G and C were given on day (d) 1 and d8 in a 21d cycle. Patients with performance status 0-2, adequate bone marrow function and calculated glomerular filtration rate (GFR) >50 ml/min were eligible. Forty-two patients were enrolled: 25 male; median age 62 (range 37-78) years. There were 26 patients (62%) with stage IV disease. One hundred and thirty-eight cycles of chemotherapy were delivered. Chemotherapy was well tolerated, allowing maintenance of planned dose intensity (DI) with mean dose delivered of 780.1 mg/m(2) (93%) and 25.6 mg/m(2) (96%) for G and C, respectively. The overall response rate was 43%. Median survival was 12.5 months with a median follow-up of 13.5 months. One year survival rate was 51%. G plus C both given on d1 and d8 (q21d) is a very active, well tolerated and convenient outpatient schedule, which maintains DI.

Hypoxia-regulated carbonic anhydrase IX expression is associated with poor survival in patients with invasive breast cancer.

Tumour hypoxia is a microenvironmental factor related to poor response to radiation, chemotherapy, genetic instability, selection for resistance to apoptosis, and increased risk of invasion and metastasis. Hypoxia-regulated carbonic anhydrase IX (CA IX) has been studied in various tumour sites and its expression has been correlated with the clinical outcome. The purpose of this study was to investigate the correlation of CA IX expression with outcome in patients with invasive breast cancer. We conducted a retrospective study examining the effects of carbonic anhydrase IX (CA IX) on survival in patients with breast cancer. To facilitate the screening of multiple tissue blocks from each patient, tissue microarrays were prepared containing between two and five representative samples of tumour per patient. Immunohistochemistry was used to examine expression of CA IX in patients with breast cancer. The study includes a cohort of 144 unselected patients with early invasive breast cancer who underwent surgery, and had CA IX expression and follow-up data available for analysis. At the time of analysis, there were 28 deaths and median follow-up of 48 months with 96% of patients having at least 2 years of follow-up. CA IX was negative for 107 patients (17 deaths) and positive for 37 patients (11 deaths). Kaplan-Meier survival curves show that survival was superior in the CA IX-negative group with a 2-year survival of 97% for negatives and 83% for positives (log-rank test P=0.01). Allowing for potential prognostic variables in a Cox regression analysis, CA IX remained a significant independent predictor of survival (P=0.035). This study showed in both univariate and multivariate analysis that survival is significantly inferior in patients with tumour expressing CA IX. Prospective studies are underway to investigate this correlation in clinical trial setting.

Monitoring the introduction of new drugs--Herceptin to cardiotoxicity.

Trastuzumab (Herceptin), currently prescribed for metastatic breast cancer, has recently been shown to be effective as adjuvant therapy in early receptor 2 (HER2)-positive breast cancer. Cardiotoxicity is a serious adverse effect. A decrease in left ventricular ejection fraction (LVEF) occurs in as many as 27% of women treated with trastuzumab when combined with standard chemotherapy. The pathophysiology of this effect, which differs from the cardiotoxicity of anthracyclines, remains poorly understood. While overt heart failure is reversed with standard therapy, the longer-term consequences of asymptomatic declines in LVEF remain unknown. Monitoring 3-monthly for 5-10% changes in LVEF, the criteria for cessation of trastuzumab therapy in the clinical trials, is not possible for the population of women who might benefit from trastuzumab for early breast cancer. Extension of this therapy to an older and less fit population than those enrolled in the trials, with less rigorous cardiac screening, may result in significantly more cardiotoxicity.

A phase I/II and pharmacokinetic study of irinotecan in combination with capecitabine as first-line therapy for advanced colorectal cancer.

PURPOSE: The aim of this study was to determine in patients with previously untreated advanced colorectal cancer the maximum tolerated dose (MTD) and safety profile of irinotecan in combination with capecitabine, to identify a recommended dose and to determine the response rate and time to disease progression. In addition, we aimed to explore the pharmacokinetic parameters of irinotecan and capecitabine when used in different sequences of administration, with irinotecan infusion either prior to or after the first intake of capecitabine. PATIENTS AND METHODS: One hundred patients were included: 43 patients were recruited into an extended phase I trial of alternating escalation in dose of both drugs where irinotecan was administered intravenously (i.v) on day 1 after first intake of capecitabine taken from days 1-14 twice daily, with cycles repeated every 3 weeks. After the determination of recommended dose a further 57 patients were treated in a phase II evaluation with the reverse sequence of drugs on day 1. Pharmacokinetic analysis was performed in patients treated at the recommended dose in two cohorts of patients in which the sequence of the first administration of each drug was reversed. RESULTS: The MTD of the combination was determined as irinotecan 300 mg/m2, with capecitabine 2000 mg/m2/day. Dose limiting toxicities were neutropenia and diarrhoea. The recommended dose is irinotecan intravenous (i.v.) 250 mg/m2 day 1 and capecitabine 2000 mg/m2/day days 1-14, every 3 weeks. Treatment was well tolerated, with diarrhoea the most common serious toxicity. Response rate in the phase II cohort was 42% [95% confidence interval (CI) 29% to 56%]. Median duration of response was 7.7 months (95% CI 7.5-8.9). Median time to progression was 8.3 months (95% CI 5.8-10). No significant effect on irinotecan pharmacokinetics was observed whatever the intake of capecitabine before or after irinotecan infusion. An effect of irinotecan on capecitabine and some capecitabine metabolites was observed, but irinotecan did not effect 5-fluorouracil (5-FU) pharmacokinetics. CONCLUSIONS: Irinotecan in combination with capecitabine is a well tolerated regimen with an activity comparable to, but more convenient than, irinotecan-5-FU i.v. combinations in patients with previously untreated advanced colorectal cancer. The pharmacokinetic data suggest that the sequence of administration does not impact significantly on the metabolism of the two drugs.

Metastatic breast cancer response after Exemestane withdrawal: a case report.

A forty-three year old female patient with right sided breast cancer was treated with adjuvant radiotherapy and Tamoxifen. She had a relapse in the right supraclavicular fossa after a disease free period of 12 years. She progressed, after a short period of disease stabilization on Idoxifene followed by a further stable period on Anastrazole. At further disease relapse, she was commenced on Exemestane. After a period of disease stabilization and subsequent disease progression in the right supraclavicular fossa, Exemestane was discontinued. Six weeks later there was a marked regression of the right supraclavicular mass. Withdrawal response to Tamoxifen is well documented. To our knowledge a similar response after Exemestane withdrawal has not been reported in the literature.

A cancer research (UK) randomized phase II study of idoxifene in patients with locally advanced/metastatic breast cancer resistant to tamoxifen.

Idoxifene is a novel selective oestrogen receptor modulator (SERM) which had greater binding affinity for the oestrogen receptor (ER) and reduced agonist activity compared with tamoxifen in preclinical studies. In a randomized phase II trial in 56 postmenopausal patients with progressive locally advanced/metastatic breast cancer we assessed whether idoxifene showed evidence of activity compared with an increased 40 mg/day dose of tamoxifen in patients who had previously demonstrated resistance to the standard 20 mg/day dose of tamoxifen. Of 47 patients eligible for response (25 idoxifene, 22 tamoxifen), two partial responses and two disease stabilizations (SD) for >6 months were seen with idoxifene (overall clinical benefit rate 16%, 95% CI 4.5-36.1%). The median duration of clinical benefit was 9.8 months. In contrast, no objective responses were seen with the increased 40 mg/day dose of tamoxifen, although two patients had SD for 7 and 14 months (clinical benefit rate 9%, 95% CI 1.1-29.2%). Idoxifene was well tolerated and the reported possible drug-related toxicities were similar in frequency to those with tamoxifen (hot flushes 13% vs 15%, mild nausea 20% vs 15%). Endocrine and lipid analysis in both groups showed a similar significant fall in serum follicle-stimulating hormone and luteinizing hormone after 4 weeks, together with a significant rise in sex hormone binding globulin levels and 11% reduction in serum cholesterol levels. In conclusion, while idoxifene was associated with only modest evidence of clinical activity in patients with tamoxifen-resistant breast cancer, its toxicity profile and effects on endocrine/lipid parameters were similar to those of tamoxifen.

A novel method for controlling the pepsin digestion of antibodies.

We have discovered that 0.5-0.8 M ammonium sulfate has a beneficial effect on the peptic digestion of several antibodies. Initially, the project was begun to address the troublesome precipitation observed when pepsin was used to digest monoclonal antibody CYT-368 (C46), an IgG2a that binds carcinoembryonic antigen. High concentrations of various salts effectively blocked this precipitation, and also accelerated the rate of digestion. Of these, ammonium sulfate had the greatest effect. Therefore, it was tested on the peptic digestion of ten other murine IgG antibodies as well as rabbit, sheep and goat immunoglobulins. Besides preventing precipitation, ammonium sulfate usefully modulated the digestion rate, accelerating the digestion of some antibodies and reducing it for others. Finally, ammonium sulfate altered the specificity of pepsin during the digestion of antibody CYT-099 (B72.3) preventing the enzyme from cleaving in the F(ab')2 region, and thereby preserving the activity of the fragment. With ammonium sulfate we were able for the first time to use pepsin to obtain active F(ab')2 in good yield from this widely used antibody.

Site-specifically radioiodinated antibody for targeting tumors.

Labeling of an antibody site specifically through its carbohydrate regions preserves its antigen-binding activity (Rodwell et al., Proc. Natl. Acad. Sci., 83: 2632, 1986). Previously site-specific labeling studies have conjugated antibodies with metallic radioisotopes or drugs. We now report site-specific labeling with a new radioiodinated compound, 2-hydroxy-5-iodo-3-methylbenzoyl hydrazide, whose synthesis we described earlier (Belinka et al., Biochemistry, 27: 3084, 1988). The compound is reacted with aldehyde groups produced by specific oxidation of the carbohydrate portion of the antibody with sodium m-periodate. Optimized conjugation conditions give good recovery of active antibody containing 10 groups per molecule. The conjugate is stable in solution for at least several weeks at both 4 and -70 degrees C. When injected into nude mice bearing LS174T human cancer xenografts, the conjugate of B72.3 antibody localizes well to tumor tissue, with low uptake by other organs. This biodistribution is similar to that of conjugate prepared by using solid-phase chloramine-T (Iodohead). There are only two significant differences. First, the carbohydrate conjugate is much less susceptible to dehalogenation, and thus shows much less thyroid uptake. Secondly, the biological half-life of the carbohydrate conjugate was about half that of the chloramine-T one. This could be due primarily to lysis of the hydrazine bond through which the antibody is attached to the compound, which would then be excreted rapidly by itself. The new reagent will be especially useful for antibodies which either cannot be labeled by chloramine-T methods, or whose activity is impaired by them.

MATCH-UP/MATRIX: a microcomputer program designed to search for protein primary structure homology.

MATCH-UP/MATRIX is a program designed to aid the investigator interested in determining primary protein structure. It is written in Applesoft BASIC for the Apple IIe microcomputer. MATCH-UP will survey any set of proteinaceous materials for amino acid sequence homology; however, it is primarily intended to compare the structures of newly sequenced peptides with the established structure of a protein with suspected homology. Any peptide-to-protein alignment which shows a homology greater than or equal to the percentage specified by the user will result in output. MATRIX will compare the sequences of two proteins (peptides) in whatever alignment specified by the user and is intended to spot insertions and/or deletions between structures.