CXD101 and nivolumab in patients with metastatic microsatellite-stable colorectal cancer (CAROSELL): a multicentre, open-label, single-arm, phase II trial

BACKGROUND

Patients with microsatellite stable (MSS) colorectal carcinoma (CRC) do not respond to immune checkpoint inhibitors. Preclinical models suggested synergistic anti-tumour activity combining CXD101 and anti-programmed cell death protein 1 treatment; therefore, we assessed the clinical combination of CXD101 and nivolumab in heavily pre-treated patients with MSS metastatic CRC (mCRC).

PATIENTS AND METHODS

This single-arm, open-label study enrolled patients aged 18 years or older with biopsy-confirmed MSS CRC; at least two lines of systemic anticancer therapies (including oxaliplatin and irinotecan); at least one measurable lesion; Eastern Cooperative Oncology Group performance status of 0, 1 or 2; predicted life expectancy above 3 months; and adequate organ and bone marrow function. Nine patients were enrolled in a safety run-in study to define a tolerable combination schedule of CXD101 and nivolumab, followed by 46 patients in the efficacy assessment phase. Patients in the efficacy assessment cohort were treated orally with 20 mg CXD101 twice daily for 5 consecutive days every 3 weeks, and intravenously with 240 mg nivolumab every 2 weeks. The primary endpoint was immune disease control rate (iDCR).

RESULTS

Between 2018 and 2020, 55 patients were treated with CXD101 and nivolumab. The combination therapy was well tolerated with the most frequent grade 3 or 4 adverse events being neutropenia (18%) and anaemia (7%). Immune-related adverse reactions commonly ascribed to checkpoint inhibitors were surprisingly rare although we did see single cases of pneumonitis, hypothyroidism and hypopituitarism. There were no treatment-related deaths. Of 46 patients assessable for efficacy, 4 (9%) achieved partial response and 18 (39%) achieved stable disease, translating to an immune disease control rate of 48%. The median overall survival (OS) was 7.0 months (95% confidence interval 5.13-10.22 months).

CONCLUSIONS

The primary endpoint was met in this phase II study, which showed that the combination of CXD101 and nivolumab, at full individual doses in the treatment of advanced or metastatic MSS CRC, was both well tolerated and efficacious.

A phase II study of retifanlimab (INCMGA00012) in patients with squamous carcinoma of the anal canal who have progressed following platinum-based chemotherapy (POD1UM-202)

Background

Locally advanced or metastatic squamous carcinoma of the anal canal (SCAC) has poor prognosis following platinum-based chemotherapy. Retifanlimab (INCMGA00012), a humanized monoclonal antibody targeting programmed death protein-1 (PD-1), demonstrated clinical activity across a range of solid tumors in clinical trials. We present results from POD1UM-202 (NCT03597295), an open-label, single-arm, multicenter, phase II study evaluating retifanlimab in patients with previously treated advanced or metastatic SCAC.

Patients and methods

Patients ≥18 years of age had measurable disease and had progressed following, or were ineligible for, platinum-based therapy. Retifanlimab 500 mg was administered intravenously every 4 weeks. The primary endpoint was overall response rate (ORR) by independent central review. Secondary endpoints were duration of response (DOR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

Overall, 94 patients were enrolled. At a median follow-up of 7.1 months (range, 0.9-19.4 months), ORR was 13.8% [95% confidence interval (CI) 7.6% to 22.5%], with one complete response (1.1%) and 12 partial responses (12.8%). Responses were observed regardless of human immunodeficiency virus or human papillomavirus status, programmed death ligand 1 (PD-L1) expression, or liver metastases. Stable disease was observed in 33 patients (35.1%) for a DCR of 48.9% (95% CI 38.5% to 59.5%). Median DOR was 9.5 months (range, 5.6 months-not estimable). Median (95% CI) PFS and OS were 2.3 (1.9-3.6) and 10.1 (7.9-not estimable) months, respectively. Retifanlimab safety in this population was consistent with previous experience for the PD-(L)1 inhibitor class.

Conclusions

Retifanlimab demonstrated clinically meaningful and durable antitumor activity, and an acceptable safety profile in patients with previously treated locally advanced or metastatic SCAC who have progressed on or are intolerant to platinum-based chemotherapy.

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Retifanlimab (PD-1 inhibitor) monotherapy demonstrated encouraging results in patients with platinum-refractory SCAC.

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Clinically meaningful antitumor activity was reported with ORR of 13.8% and stable disease in 35.1%, for a DCR of 48.9%.

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Observed responses in advanced SCAC were durable (median 9.5 months).

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Acceptable safety profile consistent with that reported for the PD-(L)1 inhibitor class.

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Promising results warrant further investigation of retifanlimab in advanced SCAC as well as earlier stages of disease.

Clinico-pathological predictors of clinical complete response in rectal cancer

PURPOSE

Prediction of clinical complete response in rectal cancer before neoadjuvant chemo-radiotherapy treatment enables treatment selection. Patients predicted to have complete response could have chemo-radiotherapy, and others could have additional doublet chemotherapy at this stage of their treatment to improve their overall outcome. This work investigates the role of clinical variables in predicting clinical complete response.

METHOD

Using the UK-based OnCoRe database (2008 to 2019), we performed a propensity-score matched study of 322 patients who received neoadjuvant chemoradiotherapy. We collected pre-treatment clinic-pathological, inflammatory and radiotherapy-related characteristics. We determined the odds for the occurrence of cCR using conditional logistic regression models. We derived the post-model Area under the Curve (AUC) as an indicator of discrimination performance and stated a priori that an AUC of 0.75 or greater was required for potential clinical utility.

RESULTS

Pre-treatment tumour diameter, mrT-stage, haemoglobin, alkaline phosphate and total radiotherapy depths were associated with cCR on univariable and multivariable analysis. Additionally, neutrophil to lymphocyte ratio (NLR), neutrophil-monocyte to lymphocyte ratio (NMLR), lymphocyte count and albumin were all significantly associated with cCR on multivariable analysis. A nomogram using the above parameters was developed with a resulting ROC AUC of 0.75.

CONCLUSION

We identified routine clinic-pathological, inflammatory and radiotherapy-related variables which are independently associated with cCR. A nomogram was developed to predict cCR. The performance characteristics from this model were on the prior clinical utility threshold. Additional research is required to develop more associated variables to better select patients with rectal cancer undergoing chemoradiotherapy who may benefit from pursuing a W&W strategy.

Trifluridine/tipiracil in combination with oxaliplatin and either bevacizumab or nivolumab in metastatic colorectal cancer: a dose-expansion, phase I study

Background

In preclinical studies trifluridine/tipiracil (FTD/TPI) plus oxaliplatin (Industriestrasse, Holzkirchen, Germany) sensitised microsatellite stable (MSS) metastatic colorectal cancer (mCRC) to anti-programmed cell death protein-1; the addition of oxaliplatin or bevacizumab (F Hoffmann- la ROCHE AG, Kaiseraugst, Switzerland) enhanced the antitumour effects of FTD/TPI. This study aimed to investigate the safety and efficacy of FTD/TPI plus oxaliplatin and either bevacizumab or nivolumab (Uxbridge business Park, Uxbridge, United Kingdom) in patients with mCRC who had progressed after at least one prior line of treatment.

Patients and methods

In 14-day cycles, patients received FTD/TPI 35 mg/m² (twice daily, days 1-5) plus oxaliplatin 85 mg/m² (day 1), and, on day 1, either bevacizumab 5 mg/kg (cohort A) or nivolumab 3 mg/kg (cohort B). Patients in Cohort B had confirmed MSS status.

Results

In total, 54 patients were enrolled: 37 in cohort A and 17 in cohort B. Recruitment in cohort B was stopped early due to the low response rate (RR) observed at interim analyses of efficacy. The most common adverse events (AEs) in cohort A were neutropenia/decreased neutrophils (75.7%), nausea (59.5%), vomiting (40.5%), diarrhoea (37.8%), peripheral sensory neuropathy (37.8%), fatigue (35.1%) and decreased appetite (35.1%). In cohort B, the most common AEs were neutropenia/decreased neutrophils (70.6%), diarrhoea (58.8%), nausea (47.1%), vomiting (47.1%), fatigue (47.1%), asthenia (41.2%), paraesthesia (41.2%), thrombocytopenia/decreased platelets (35.3%) and decreased appetite (35.3%). Confirmed objective RR was 17.1% in cohort A and 7.1% in cohort B; the corresponding values for median progression-free survival in the two cohorts were 6.3 and 6.0 months.

Conclusion

FTD/TPI plus oxaliplatin and bevacizumab or nivolumab had an acceptable safety profile and demonstrated antitumour activity in previously treated patients with mCRC.

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This study evaluated the safety and efficacy of FTD/TPI plus oxaliplatin and either bevacizumab or nivolumab in mCRC patients.

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FTD/TPI plus oxaliplatin in combination with bevacizumab or nivolumab had an acceptable and manageable safety profile.

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Antitumour activity was observed following treatment with FTD/TPI plus oxaliplatin and bevacizumab.

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Despite a modest RR with the addition of nivolumab, survival data were promising in these poor-prognosis patients.

Trifluridine/tipiracil plus bevacizumab in patients with untreated metastatic colorectal cancer ineligible for intensive therapy: the randomized TASCO1 study

BACKGROUND

We designed an open-label, noncomparative phase II study to assess the safety and efficacy of first-line treatment with trifluridine/tipiracil plus bevacizumab (TT-B) and capecitabine plus bevacizumab (C-B) in untreated patients with unresectable metastatic colorectal cancer (mCRC) who were not candidates for combination with cytotoxic chemotherapies.

PATIENTS AND METHODS

From 29 April 2016 to 29 March 2017, 153 patients were randomly assigned (1:1) to either TT-B (N = 77) or C-B (N = 76). The primary end point was progression-free survival (PFS). The primary PFS analysis was performed after 100 events (radiological progression or death) were observed. Secondary end points included overall survival (OS), quality of life (QoL; QLQ-C30 and QLQ-CR29 questionnaires), and safety.

RESULTS

Median (range) duration of treatment was 7.8 (6.0-9.7) months and 6.2 (4.1-9.1) months in the TT-B and C-B groups, respectively. Median (range) PFS was 9.2 (7.6-11.6) and 7.8 (5.5-10.1) months, respectively. Median (range) OS was 18 (15.2 to NA) and 16.2 (12.5 to NA) months, respectively. QoL questionnaires showed no relevant changes over time for either treatment. Therapies were well tolerated. Patients receiving TT-B had more grade ≥3 neutropenia (47% versus 5% with C-B). Patients receiving C-B had more grade ≥3 hand-foot syndrome (12% versus 0% with TT-B) and grade ≥3 diarrhea (8% versus 1% with TT-B), consistent with the known safety profiles of these agents.

CONCLUSION

TT-B treatment showed promising clinical activity in untreated patients with unresectable mCRC ineligible for intensive therapy, with an acceptable safety profile and no clinically relevant changes in QoL.

CLINICAL TRIAL INFORMATION

NCT02743221 (ClinicalTrials.gov).

Novel phase I trial design to evaluate the addition of cediranib or selumetinib to preoperative chemoradiotherapy for locally advanced rectal cancer: the DREAMtherapy trial

BACKGROUND

The DREAMtherapy (Dual REctal Angiogenesis MEK inhibition radiotherapy) trial is a novel intertwined design whereby two tyrosine kinase inhibitors (cediranib and selumetinib) were independently evaluated with rectal chemoradiotherapy (CRT) in an efficient manner to limit the extended follow-up period often required for radiotherapy studies.

PATIENTS AND METHODS

Cediranib or selumetinib was commenced 10 days before and then continued with RT (45 Gy/25#/5 wks) and capecitabine (825 mg/m2 twice a day (BID)). When three patients in the cediranib 15-mg once daily (OD) cohort were in the surveillance period, recruitment to the selumetinib cohort commenced. This alternating schedule was followed throughout. Three cediranib (15, 20 and 30 mg OD) and two selumetinib cohorts (50 and 75 mg BID) were planned. Circulating and imaging biomarkers of inflammation/angiogenesis were evaluated.

RESULTS

In case of cediranib, dose-limiting diarrhoea, fatigue and skin reactions were seen in the 30-mg OD cohort, and therefore, 20 mg OD was defined as the maximum tolerated dose. Forty-one percent patients achieved a clinical or pathological complete response (7/17), and 53% (9/17) had an excellent clinical or pathological response (ECPR). Significantly lower level of pre-treatment plasma tumour necrosis factor alpha (TNFα) was found in patients who had an ECPR. In case of selumetinib, the 50-mg BID cohort was poorly tolerated (fatigue and diarrhoea); a reduced dose cohort of 75-mg OD was opened which was also poorly tolerated, and further recruitment was abandoned. Of the 12 patients treated, two attained an ECPR (17%).

CONCLUSIONS

This novel intertwined trial design is an effective way to independently investigate multiple agents with radiotherapy. The combination of cediranib with CRT was well tolerated with encouraging efficacy. TNFα emerged as a potential predictive biomarker of response and warrants further evaluation.

Biomarker concordance between primary colorectal cancer and its metastases

Background

The use of biomarkers to target anti-EGFR treatments for metastatic colorectal cancer (CRC) is well-established, requiring molecular analysis of primary or metastatic biopsies. We aim to review concordance between primary CRC and its metastatic sites.

Methods

A systematic review and meta-analysis of all published studies (1991–2018) reporting on biomarker concordance between primary CRC and its metastatic site(s) was undertaken according to PRISMA guidelines using several medical databases. Studies without matched samples or using peripheral blood for biomarker analysis were excluded.

Findings

61 studies including 3565 patient samples were included. Median biomarker concordance for KRAS (n = 50) was 93.7% [[67], [68], [69], [70], [71], [72], [73], [74], [75], [76], [77], [78], [79], [80], [81], [82], [83], [84], [85], [86], [87], [88], [89], [90], [91], [92], [93], [94], [95], [96], [97], [98], [99], [100]], NRAS (n = 11) was 100% [[90], [91], [92], [93], [94], [95], [96], [97], [98], [99], [100]], BRAF (n = 22) was 99.4% [[80], [81], [82], [83], [84], [85], [86], [87], [88], [89], [90], [91], [92], [93], [94], [95], [96], [97], [98], [99], [100]], and PIK3CA (n = 17) was 93% [[42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54], [55], [56], [57], [58], [59], [60], [61], [62], [63], [64], [65], [66], [67], [68], [69], [70], [71], [72], [73], [74], [75], [76], [77], [78], [79], [80], [81], [82], [83], [84], [85], [86], [87], [88], [89], [90], [91], [92], [93], [94], [95], [96], [97], [98], [99], [100]]. Meta-analytic pooled discordance was 8% for KRAS (95% CI = 5–10%), 8% for BRAF (95% CI = 5–10%), 7% for PIK3CA (95% CI = 2–13%), and 28% overall (95% CI = 14–44%). The liver was the most commonly biopsied metastatic site (n = 2276), followed by lung (n = 438), lymph nodes (n = 1123), and peritoneum (n = 132). Median absolute concordance in multiple biomarkers was 81% (5–95%).

Interpretation

Metastatic CRC demonstrates high concordance across multiple biomarkers, suggesting that molecular testing of either the primary or liver and lung metastasis is adequate. More research on colorectal peritoneal metastases is required.

Waiting Times for Treatment of Rectal Cancer in North West England

An interim goal of the NHS National Cancer Plan is that, by 2005, patients with cancer should be treated within one month of diagnosis and within two months from urgent general practitioner referral. Preoperative radiotherapy for rectal cancer reduces the risk of local recurrence and may translate into improved patient survival. We conducted a prospective audit of existing waiting times for preoperative radiotherapy experienced by 65 patients with rectal cancer referred to the Christie Cancer Centre, Manchester, UK, between May and November 2002. The median time between referral from the surgeon to the start of radiotherapy was 40 days (range 11-85). Only 4 patients (6%) received radiotherapy within 28 days of referral by the surgeon. 62 patients (95%) underwent surgery within 14 days of completing radiotherapy. Delays in the provision of preoperative radiotherapy were primarily due to shortages of radiography staff and equipment. Lack of such infrastructure will prove a major stumbling block to achieving the targets of the NHS Cancer Plan.

Oxaliplatin and 5-FU/folinic acid (modified FOLFOX6) with or without aflibercept in first-line treatment of patients with metastatic colorectal cancer: the AFFIRM study

BACKGROUND

The combination of aflibercept with FOLFIRI has been shown to significantly prolong overall survival in patients with metastatic colorectal cancer (mCRC) after progression on oxaliplatin-based therapy. This trial evaluated the addition of aflibercept to oxaliplatin-based first-line treatment of patients with mCRC.

PATIENTS AND METHODS

Patients with mCRC were randomized to receive first-line therapy with mFOLFOX6 plus aflibercept (4 mg/kg) or mFOLFOX6 alone. The primary end point of this phase II study was the progression-free survival (PFS) rate at 12 months in each arm. The analysis of efficacy between the arms was a pre-planned secondary analysis.

RESULTS

Of 236 randomized patients, 227 and 235 patients were evaluable for the primary efficacy analysis and safety, respectively. The probabilities of being progression-free at 12 months were 25.8% [95% confidence interval (CI) 17.2-34.4] for the aflibercept/mFOLFOX6 arm and 21.2% (95% CI 12.2-30.3) for the mFOLFOX6 arm. The median PFS was 8.48 months (95% CI 7.89-9.92) for the aflibercept/mFOLFOX6 arm and 8.77 months (95% CI 7.62-9.27) for the mFOLFOX6 arm; the hazard ratio of aflibercept/mFOLFOX6 versus mFOLFOX6 was 1.00 (95% CI 0.74-1.36). The response rates were 49.1% (95% CI 39.7-58.6) and 45.9% (95% CI 36.4-55.7) for patients treated with and without aflibercept, respectively. The most frequent treatment-emergent grade 3/4 adverse events (AEs) excluding laboratory abnormalities reported for aflibercept/mFOLFOX6 versus mFOLFOX6 were neuropathy (16.8% versus 17.2%) and diarrhea (13.4% versus 5.2%). Neutropenia grade 3/4 occurred in 36.1% versus 29.3%. The most common vascular endothelial growth factor inhibition class-effect grade 3/4 AEs for aflibercept/mFOLFOX6 versus mFOLFOX6 were hypertension (35.3% versus 1.7%), proteinuria (9.2% versus 0%), deep vein thrombosis (5.9% versus 0.9%) and pulmonary embolism (5.9% versus 5.2%).

CONCLUSION

No difference in PFS rate was observed between treatment groups. Adding aflibercept to first-line mFOLFOX6 did not increase efficacy but was associated with higher toxicity.

CLINICAL TRIAL NUMBER

NCT00851084, www.clinicaltrials.gov, EudraCT 2008-004178-41.

A phase I study of sunitinib in combination with FOLFIRI in patients with untreated metastatic colorectal cancer

BACKGROUND

This study evaluated the maximum tolerated dose (MTD) of sunitinib, a multitargeted tyrosine kinase inhibitor, combined with FOLFIRI (irinotecan 180 mg/m2 given over 90 min i.v. and l-leucovorin 200 mg/m2 given over 120 min on day 1, followed by 5-FU 400 mg/m2 bolus and then 2400 mg/m2 infused over 46 h) in untreated metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

In this multicentre, phase I, open-label, dose-finding trial, FOLFIRI was administered every 2 weeks. Two sunitinib regimens were explored: Schedule 4/2 (4 weeks on, 2 weeks off; 37.5 and 50 mg/day) and continuous daily dosing (CDD; 37.5 and 25 mg/day). Dose-limiting toxic toxicities (DLTs) were evaluated during weeks 1-6. Efficacy was a secondary objective.

RESULTS

Thirty-seven patients were enrolled. The 37.5 mg/day Schedule 4/2 cohort had zero of six DLTs, was expanded by 15 patients and declared the MTD. The MTD was exceeded at all other sunitinib doses and schedules; DLTs included febrile neutropenia (n=1), grade 4 neutropenia (n=4) and grade 3 deep vein thrombosis with grade 4 neutropenia (n=1). At the MTD, non-haematologic grade 3/4 adverse events with a frequency of >10% were diarrhoea, vomiting and lethargy, and the objective response rate was 57.9% (95% confidence interval 33.5-79.7).

CONCLUSIONS

The MTD of sunitinib combined with FOLFIRI in chemotherapy-naive mCRC was 37.5 mg/day on Schedule 4/2. CDD of sunitinib at 37.5 or 25 mg/day plus FOLFIRI was not feasible.

Adipose progenitor cells increase fibronectin matrix strain and unfolding in breast tumors

Increased stiffness represents a hallmark of breast cancer that has been attributed to the altered physicochemical properties of the extracellular matrix (ECM). However, the role of fibronectin (Fn) in modulating the composition and mechanical properties of the tumor-associated ECM remains unclear. We have utilized a combination of biochemical and physical science tools to evaluate whether paracrine signaling between breast cancer cells and adipose progenitor cells regulates Fn matrix assembly and stiffness enhancement in the tumor stroma. In particular, we utilized fluorescence resonance energy transfer imaging to map the molecular conformation and stiffness of Fn that has been assembled by 3T3-L1 preadipocytes in response to conditioned media from MDA-MB231 breast cancer cells. Our results reveal that soluble factors secreted by tumor cells promote Fn expression, unfolding, and stiffening by adipose progenitor cells and that transforming growth factor-β serves as a soluble cue underlying these changes. In vivo experiments using orthotopic co-transplantation of primary human adipose-derived stem cells and MDA-MB231 into SCID mice support the pathological relevance of our results. Insights gained by these studies advance our understanding of the role of Fn in mammary tumorigenesis and may ultimately lead to improved anti-cancer therapies.

Treatments and outcomes of peritoneal surface tumors through a centralized national service (United kingdom)

PURPOSE

Treatment of peritoneal surface malignancies with combined cytoreductive surgery and heated intraperitoneal chemotherapy may improve oncologic outcome. To better define treatment pathways, five-year results in patients referred to one of two centralized national treatment centers in the United Kingdom were analyzed.

METHODS

A prospective database of patients referred to the Manchester Peritoneal Tumor Service, established in 2002, was analyzed. Outcomes were evaluated using Kaplan-Meier life tables and Cox models.

RESULTS

Two hundred seventy-eight patients (median age, 56.9 (range, 16-86) years) were considered by a dedicated multidisciplinary team and tracked on seven clinical pathways. Among the 118 surgically treated, the most common diagnosis was pseudomyxoma peritonei (101 patients, 86%). Major complications occurred in 11 patients (9%); there was no 30-day mortality. Where complete cytoreduction was achieved, three-year and five-year tumor-related survival rates were 94% and 86%, respectively. In the Cox model, incompleteness of cytoreduction (P = 0.001) and high-grade tumor (P < 0.0001) were independent prognosticators of poor outcome.

CONCLUSION

The establishment of a national treatment center has allowed refinement of techniques to achieve internationally recognized results. Having achieved low levels of morbidity and mortality in the treatment of mainly pseudomyxoma peritonei of appendiceal origin, the technique of cytoreductive surgery and heated intraperitoneal chemotherapy may be considered for peritoneal carcinomatosis of colorectal origin.

Alternating irinotecan with oxaliplatin combined with UFT plus leucovorin (SCOUT) in metastatic colorectal cancer

Tegafur-uracil (UFT) plus leucovorin (LV, folinic acid) with alternating irinotecan and oxaliplatin were effective and well tolerated in patients with metastatic colorectal cancer (mCRC) in a phase I study. This study expanded the maximum tolerated dose group. Patients aged >or=18 years had histologically confirmed, inoperable, previously untreated, measurable mCRC. Patients received irinotecan 180 mg m(-2) on day 1, oxaliplatin 100 mg m(-2) on day 15 and UFT 250 mg m(-2) plus LV 90 mg on days 1-21 every 28 days. The phase I/II study comprised 45 patients, 29 at the maximum tolerated dose (MTD). The response rate in 38 evaluable patients was 63% (95% confidence interval (CI): 49-80). Median time to progression and overall survival were 8.7 months (95% CI: 7.9-10.4) and 16.8 months (95% CI: 9.6-25.3), respectively. In the MTD group, one patient had grade 3 leucopenia; one had grade 3 neutropaenia; three had grade 3 diarrhoea; and one had grade 3 neurotoxicity. No hand-foot syndrome grade >1 was seen. In total, 67% of eligible patients received second-line therapy. UFT plus LV with alternating irinotecan and oxaliplatin is an efficacious first-line treatment for mCRC, with minimal neurotoxicity and hand-foot syndrome.

A phase II study evaluating the use of concurrent mitomycin C and capecitabine in patients with advanced unresectable pseudomyxoma peritonei

Pseudomyxoma peritonei (PMP) is a rare neoplastic process characterised by progressive intra-abdominal dissemination of mucinous tumour, and generally considered resistant to systemic chemotherapy. A phase II study in patients with advanced unresectable PMP was undertaken to evaluate the combination of systemic concurrent mitomycin C (7 mg m(-2) i.v. on day 1) and capecitabine (1250 mg m(-2) b.d. on days 1-14) in a 3-weekly cycle (MCap). Response was determined by semiquantitative assessment of disease volume on serial computed tomographic (CT) scans and serum tumour marker (CEA, CA125, CA19-9) changes at 12 weeks. Between 2003 and 2006, 40 patients were recruited through a national centre for the treatment of peritoneal surface tumours. At baseline, 23 patients had progressive disease and 17 had stable disease. Of 39 assessable patients, 15 (38%, 95% confidence intervals (CIs): 25, 54%) benefited from chemotherapy in the form of either reductions in mucinous deposition or stabilisation of progressive pretreatment disease determined on CT scan. Notably, two patients, originally considered unresectable, following MCap and re-staging underwent potentially curative cytoreductive surgery. Grade 3/4 toxicity rates were low (6%, 95% CIs: 4, 9%). Twenty out of 29 assessed patients (69%, 95% CIs: 51, 83%) felt that their Global Health Status improved during chemotherapy. This is the first trial to demonstrate an apparent benefit of systemic chemotherapy in patients with advanced unresectable PMP.

Alternating irinotecan with oxaliplatin combined with UFT plus leucovorin (LV) (SCOUT) in patients with advanced colorectal cancer (ACRC): A phase I/II study

4084

Background: The feasibility of UFT (tegafur-uracil) plus LV with alternating irinotecan and oxaliplatin was investigated in a two-stage, phase I/II, open-label, dose-finding trial in patients with ACRC. The study is now closed. Here we present results from the phase II cohort and overall results from the phase I/II study. Methods: Eligible patients aged =18 years had histologically confirmed, advanced, inoperable, measurable metastatic disease, no prior chemotherapy other than adjuvant bolus 5-FU administered =6 months previously, and adequate hematologic, hepatobiliary, and renal function. Patients in the phase I study received irinotecan 180 mg/m2 on d1, oxaliplatin 85–100 mg/m2 on d15 plus UFT 200–300 mg/m2/d with LV 90 mg/d on d1–21 of a 28-d cycle. Diarrhea, lethargy, and vomiting were dose limiting. The maximum tolerated dose (MTD) established was irinotecan 180 mg/m2, oxaliplatin 100 mg/m2, UFT 250 mg/m2/d, and LV 90 mg/day. Patients were treated at the MTD in the phase II study. Primary endpoints in the phase II study were objective response rate (ORR) and time to progression (TTP). Results: Forty-five patients (median age 62 [range 24–79] years, median 4 marker lesions) were entered, 16 and 29 patients in the phase I and II studies, respectively. The ORR in all 38 evaluable patients was 66% (95% CI 49–80%), with clinical benefit (CB) in 89% (95% CI 75–97%). At a median follow-up of 10.3 months, median TTP was 8.5 months (95% CI -7.6 to 10.4 months) in 40 evaluable patients and median OS (ITT population; n=45) was 16.8 months (95% CI -11.3 to 28.3 months). In the phase II study (n=29) median TTP was 8.1 months (95% CI -6.7 to 11.3 months) and median OS was 19.6 months (95% CI -7.7 to >25.6 months); ORR in 25 evaluable patients was 68% (95% CI -46.5 to 85.1%) with CB in 100% (95% CI -86.3 to 100%). Of 30 patients with confirmed radiologic progression, 21 (70%) had second-line therapy. At the MTD, 3 patients (10%) had grade 3 diarrhea, 1 patient (3%) had grade 3 neurotoxicity, and 2 patients (7%) had grade 2 alopecia. No hand-foot syndrome (HFS) was seen. Conclusions: UFT plus LV with alternating irinotecan and oxaliplatin is an efficacious first-line treatment for patients with ACRC, with minimal alopecia and neurotoxicity and no HFS.

No significant financial relationships to disclose.

Adjuvant chemoradiotherapy for gastric carcinoma: dosimetric implications of conventional gastric bed irradiation and toxicity

AIMS

Recently, a survival advantage has been shown using adjuvant chemoradiotherapy after complete resection of gastric cancer. If survival advantages are to be maintained, treatment-related complications must be minimised. In this study, we explored the dosimetric implications and toxicity of conventional large field gastric bed irradiation.

MATERIALS AND METHODS

Between 2000 and 2002, 16 patients received adjuvant 5-fluorouracil (5-FU) chemoradiotherapy after complete resection of gastric cancer. Radiotherapy was simulator planned using anterior-posterior parallel opposed fields to 45 Gy in 25 daily fractions over 5 weeks.

RESULTS

Thirteen patients (81%) completed radiotherapy and eight patients (50%) completed chemotherapy as planned. Toxicity was the main factor for discontinuation. Substantial dose inhomogeneities were shown using retrospective computed tomography recreation of dose-volume histograms (DVHs) of the organs at risk.

CONCLUSIONS

Although the delivery of chemoradiotherapy using conventional two-dimensional simulator planning is a feasible technique, significant under-appreciation of dose inhomogeneity exists. Conformal computed tomography planning is vital to document doses received by organs at risk, especially the spinal cord and kidneys, which may receive high doses, and prospectively correlate these with acute and long-term toxicity in order to redefine organ at risk tolerances in the setting of chemoradiation.

Concurrent irinotecan, oxaliplatin and UFT in first-line treatment of metastatic colorectal cancer: a phase I study

The feasibility of combining UFT plus leucovorin (LV) with alternating irinotecan and oxaliplatin was investigated in the first-line treatment of patients with advanced colorectal cancer. Twenty-five patients, median age 63 (range 24–79) years, World Health Organisation performance status 0–2 and median four marker lesions, received irinotecan 180 mg m⁻² on day 1, oxaliplatin 85–100 mg m⁻² on day 15 and UFT 200–300 mg m⁻² day⁻¹ with LV 90 mg day⁻¹, days 1–21 of a 28-day cycle. Patients were treated in cohorts of three. At the highest dose (irinotecan 180 mg m⁻², oxaliplatin 100 mg m⁻² and UFT 300 mg m⁻² day⁻¹), three of four patients experienced grade 3 toxicity. Diarrhoea, lethargy and vomiting were dose-limiting. Three of nine patients had grade 2 toxicities at the maximum tolerated dose (irinotecan 180 mg m⁻², oxaliplatin 100 mg m⁻² and UFT 250 mg m⁻² day⁻¹). There were no grade 3 toxicities in the first month of therapy. The overall response rate was 71% in 21 evaluable patients; progression-free survival was 8.8 months. Alternating irinotecan and oxaliplatin plus UFT is an effective and well-tolerated first-line treatment for patients with advanced colorectal cancer. We recommend a dose of irinotecan 180 mg m⁻² on day 1, oxaliplatin 100 mg m⁻² on day 15 and UFT 250 mg m⁻² day⁻¹ with LV 90 mg day⁻¹ on days 1–21 of a 28-day cycle for future studies.

Preoperative radiotherapy for operable rectal cancer--is a lower dose to a reduced volume acceptable?

AIMS

A retrospective audit was carried out to determine the rate of local recurrence (recurrent tumour within the lesser pelvis or the perineal wound) in 88 rectal cancer patients treated with 20 Gy/four fractions of adjuvant preoperative radiotherapy and curative surgery.

MATERIALS AND METHODS

All patients were followed-up by clinical examination with rigid sigmoidoscopy at 6 monthly intervals if the rectum was intact, and computed tomography of the pelvis at 1, 2 and 5 years after surgery. In total, 171 patients with rectal cancer were identified under the care of one surgeon over a period of 11 years from May 1992 to April 2003. We excluded patients with rectal cancer from preoperative adjuvant radiotherapy if they had evidence at presentation of distant metastases, if they had fixed rectal tumours, were treated by local excision and had previous radiotherapy to the pelvis. On this basis, only 88 were considered for preoperative radiotherapy and curative resection with a median follow-up of 5.16 years.

RESULTS

The 5-year survival by stage was Dukes A 96%, Dukes B 65% and Dukes C 36%. Overall, four patients (of 88) developed a recurrence within the lesser pelvis or the perineal wound, giving a local recurrence of 4.2% at 3 years (from a Kaplan-Meier graph).

CONCLUSIONS

This single-centre audit suggests that a lower dose of radiotherapy to a smaller volume provides an acceptable local recurrence rate that compares very favourably with the well-publicised Swedish and Dutch trials of 25 Gy/five fractions. It was not the intention of this audit to suggest that this dose should be widely adopted. However, given the long-term gastrointestinal morbidity and risk of second malignancies, we advise caution when formulating even more intensive radiotherapy and chemoradiotherapy regimens for rectal cancer.

A specific cadherin phenotype may characterise the disseminating yet non-metastatic behaviour of pseudomyxoma peritonei

Pseudomyxoma peritonei (PMP) is a rare neoplasm of mainly appendiceal origin, characterised by excess intra-abdominal mucin production leading to high morbidity and mortality. While histological features are frequently indolent, this tumour disseminates aggressively throughout the abdominal cavity, yet seldom metastasises. This study determined the expression of several markers of colorectal differentiation (carcinoembryonic antigen (CEA), cytokeratins (CK20 and CK7), epithelial membrane antigen), mucin production (MUC-2, interleukin-9 (IL-9), IL-9 receptor (IL-9Rα)), and cell adhesion (N- and E-cadherin, vimentin) in PMP tissue (n=26) compared with expressions in normal colonic mucosa (n=19) and colorectal adenocarcinoma (n=26). Expressions of CEA and cytokeratins were similar for PMP as those in colorectal adenocarcinomas with the exception that the CK20−/CK7− pattern was rare in PMP (Fisher's exact test: P=0.001). Similarly, expressions of mucin-related proteins were comparable for adenocarcinoma and PMP, with the exception that IL-9 expression was uncommon in adenocarcinoma (P=0.009). Pseudomyxoma peritonei demonstrated a specific pattern of adhesion-related protein expressions of increased N-cadherin, reduced E-cadherin, and increased vimentin (P=0.004), a phenotype suggesting a possible epithelial–mesenchymal transition state. Primary PMP cell cultures were successfully maintained and demonstrated marker expressions similar to those seen in in vivo tissues. These early characterisation studies demonstrate similarities between PMP and colorectal adenocarcinoma, but also reveal a specific cadherin phenotype that may characterise the distinct non-metastasising behaviour of PMP, and form the basis for future mechanistic and therapy-targeting research.

Mechanisms of improved survival from intensive followup in colorectal cancer: a hypothesis

A meta-analysis of six randomised trials demonstrated that intensive followup in colorectal cancer was associated with an absolute reduction in all-cause 5-year mortality of 10% (95% confidence interval (CI): 4–16) – however, only two percent (95% CI: 0–5) was attributable to cure from salvage re-operations. We postulate that other factors, such as increased psychological well-being and/or altered lifestyle, and/or improved treatment of coincidental disease may contribute to the remaining lives saved, and form important future research questions.

Patterns of local disease failure and outcome after salvage surgery in patients with anal cancer

Background

Salvage surgery for anal cancer is usually reserved for local disease failure, but issues relating to the prediction of local failure and surgical outcome are ill defined.

Methods

Between 1988 and 2000, 254 patients with non-metastatic anal epidermoid carcinoma were treated at a regional cancer centre with radiotherapy (n = 127) or chemoradiotherapy (n = 127).

Results

There were 99 local disease failures (39·0 per cent), all but five occurring within 3 years of initial treatment. Increasing age (P &lt; 0·001, Cox model), total radiation dose (P = 0·004) and tumour stage (P = 0·010) were independent predictors of local failure. The overall 3- and 5-year survival rates after local disease failure were 46 and 29 per cent; the corresponding rates after salvage surgery (73 patients) were 55 and 40 per cent. A positive resection margin was the strongest negative predictor of survival after salvage surgery (P = 0·008, log rank test). Of 52 patients treated before the routine consideration of primary plastic reconstruction, delayed perineal wound healing occurred in 22 (42 per cent).

Conclusion

In the management of anal cancer, local disease failure is a major clinical problem requiring early detection followed by radical surgery, often accompanied by plastic reconstruction. By implication, these factors favour the centralization of treatment for this uncommon cancer to a multidisciplinary oncology team.

Phase I dose-escalation trial of irinotecan with continuous infusion 5-FU first line, in metastatic colorectal cancer

This single-centre phase I trial was designed to determine the maximum tolerated dose of irinotecan and the recommended dose to use in combination with a fixed dose of 5-fluorouracil (5-FU) administered as a protracted venous infusion, for the first-line treatment of metastatic colorectal cancer (CRC). Tolerability and efficacy were secondary end points. In all, 22 patients, median age 57 years, were treated with escalating, weekly doses of irinotecan (50, 75, 100 and 85 mg m⁻²) in combination with 250 mg m⁻² 5-FU administered as a continuous infusion. All patients had measurable disease. The combination was well tolerated up to an irinotecan dose of 75 mg m⁻². However, three out of five patients at the 100 mg m⁻² irinotecan dose level had their dose reduced due to multiple grade 2 toxicities, and eventually one patient stopped treatment due to grade 3 diarrhoea and multiple grade 2 toxicities. Subsequent patients were recruited at an irinotecan dose level of 85 mg m⁻². The overall response rate was 55%, comprising one complete and 11 partial responses (PRs). Six patients also achieved sustained stable disease (SD), giving a clinical benefit (complete response/PR/SD) response of 82%. The median duration of response was 238 days (8.5 months) and median time to progression was 224 days (8.0 months). Two patients who achieved PRs underwent partial hepatectomies. Thus, irinotecan (85 mg m⁻²) combined with a continuous infusion of 5-FU (250 mg m⁻²) is an active and well-tolerated regimen for the treatment of metastatic CRC. It represents an effective treatment for patients who require close supervision and support, throughout their initial exposure to chemotherapy for this disease, and this dose combination was recommended for an ongoing phase II study.

Waiting times for treatment of rectal cancer in North West England

An interim goal of the NHS National Cancer Plan is that, by 2005, patients with cancer should be treated within one month of diagnosis and within two months from urgent general practitioner referral. Preoperative radiotherapy for rectal cancer reduces the risk of local recurrence and may translate into improved patient survival. We conducted a prospective audit of existing waiting times for preoperative radiotherapy experienced by 65 patients with rectal cancer referred to the Christie Cancer Centre, Manchester, UK, between May and November 2002. The median time between referral from the surgeon to the start of radiotherapy was 40 days (range 11-85). Only 4 patients (6%) received radiotherapy within 28 days of referral by the surgeon. 62 patients (95%) underwent surgery within 14 days of completing radiotherapy. Delays in the provision of preoperative radiotherapy were primarily due to shortages of radiography staff and equipment. Lack of such infrastructure will prove a major stumbling block to achieving the targets of the NHS Cancer Plan.

Anal Canal Cancer and Chemoradiation Treatment in Two Patients with Systemic Lupus Erythematosus treated by Chronic Therapeutic Immunosuppression

Two case reports of anal cancer developing during chronic therapeutic immunosuppression for systemic lupus erythematosus (SLE) and their cancer management are presented. The complex issues of delivery of curative chemoradiation treatment for anal cancer in the context of co-existing autoimmune connective tissue disease (AICD) are discussed. These two cases show that combined chemotherapy and radiation regimens are possible in patients with SLE. However, frequent, careful assessment with judicious and prompt management of haematological and other complications during treatment is important.

Modified de Gramont with oxaliplatin in the first-line treatment of advanced colorectal cancer

We previously reported high activity for oxaliplatin and a modified de Gramont regimen (OxMdG) in a single centre study of patients with metastatic colorectal cancer. We now report results with a further 56 patients treated at 14 centres. Low rates of grade 3 and 4 toxicity were seen, with no toxic deaths. Objective response rates were CR/PR=53%; NC=34.7%; PD=12.2%. Median time to progression was 8.3 months and overall survival was 14.5 months. This regimen is more convenient than those based around the conventional de Gramont regimen but is highly active and well tolerated; it forms part of a current UK MRC phase 3 trial.

Vascular endothelial growth factors C and D and lymphangiogenesis in gastrointestinal tract malignancy

Vascular endothelial growth factor-C (VEGF-C) and VEGF-D are members of the VEGF family of cytokines and have angiogenic and lymphangiogenic actions. In gastric adenocarcinoma, VEGF-C mRNA and tissue protein expression correlate with lymphatic invasion, lymph node metastasis and in some reports, venous invasion and reduced 5-year survival. Patients with gastric adenocarcinomas containing high levels of VEGF-C expression have significantly reduced 5-year survival rates, and VEGF-C expression is an independent prognostic risk factor for death. The role of VEGF-C in oesophageal squamous and colorectal cancer and VEGF-D in colorectal cancer is not clear, with conflicting reports in the published literature. In order to exploit potential therapeutic applications, further research is necessary to define the precise roles of these cytokines in health and disease.

Use of the Bard Memotherm self-expanding metal stent in the palliation of colonic obstruction

BACKGROUND

Self-expanding metal stents (SEMS) are a recognized means of palliating large bowel obstruction due to colonic neoplasia. The literature mainly relates to the use of modified esophageal stents (expanded diameter, 18-22 mm) in the colorectum. Stent migration has been a common complication and may be related to expanded stent diameter. This series reports our experience with the Memotherm Colorectal SEMS (expanded diameter, 25-30 mm).

METHODS

Prospective data were collected from February 1999 to September 2000. Sixteen patients (age range = 61-99 years) were considered for the Memotherm Colorectal SEMS. Stents were inserted radiologically under fluoroscopic control. Outcome was classified as a technical success (stent in correct position and expanded) and a clinical success (colon decompressed, symptoms relieved, and bowels working).

RESULTS

Thirteen cases (81%) underwent successful SEMS placement. These were technically and clinically successful. Two cases required insertion of two overlapping stents to traverse long strictures. Three unsuccessful cases were emergency presentations in which a guidewire could not be passed across the lesion. Two of these were due to benign strictures and the third to extrinsic compression by ovarian carcinoma.

CONCLUSION

In our experience, the Memotherm Colorectal SEMS was easy to use, was effective in the palliation of obstructing colorectal carcinoma, and appeared to reduce the risk of stent migration.

Why hasn't the National Institute been 'NICE' to patients with colorectal cancer? National Institute of Clinical Excellence

British Journal of Cancer (2002) 86, 1667–1669. doi:10.1038/sj.bjc.6600369www.bjcancer.com

© 2002 Cancer Research UK

The relative importance of NADPH: cytochrome c (P450) reductase for determining the sensitivity of human tumour cells to the indolequinone EO9 and related analogues lacking functionality at the C-2 and C-3 positions

Analogues of EO9 (3-hydroxymethyl-5-aziridinyl-1-methyl-2[1H-indole-4-7-dione]prop-2-e n-1-ol) which lack functionality at either the C-2 or C-3 position were synthesised. The aim was to establish the importance of each group towards toxicity and to give an indication as to whether substitution at either position altered activation and toxicity after metabolism by cellular NADPH: cytochrome c (P450) reductase (P450R). MDA231 breast cancer cells were transfected with the cDNA for human P450R and stable clones were isolated. These high P450R-expressing clones were used to determine the aerobic and hypoxic toxicity of EO9 and the two analogues that lacked functionality at either C-2 or C-3. The results showed that P450R was strongly implicated in the bioactivation of EO9 and its analogues under both of these conditions. This data also showed that the C-3 functionality was primarily implicated in hypoxic toxicity.

NADPH:cytochrome c (P450) reductase activates tirapazamine (SR4233) to restore hypoxic and oxic cytotoxicity in an aerobic resistant derivative of the A549 lung cancer cell line

Tirapazamine (TPZ, SR4233, WIN 59075) is a bioreductive drug that is activated in regions of low oxygen tension to a cytotoxic radical intermediate. This labile metabolite shows high selective toxicity towards hypoxic cells, such as those found in solid tumours. Under aerobic conditions, redox cycling occurs with subsequent generation of superoxide radicals, which are also cytotoxic. NADPH:cytochrome c (P450) reductase (P450R) is a one-electron reducing enzyme that efficiently activates TPZ. Recently a derivative of the A549 non-small cell lung cancer cell line (A549c50) was generated that showed substantially reduced P450R activity compared to its parental line (Elwell et al (1997) Biochem Pharmacol 54: 249-257). Here, it is demonstrated that the A549c50 cells are markedly more resistant to TPZ under both aerobic and hypoxic conditions. In addition, these cells have a dramatically impaired ability to metabolize TPZ to its two-electron reduction product, SR4317, under hypoxic conditions when compared to wild-type cells. P450R activity in the A549c50 cells was reintroduced to similar levels as that seen in the parental A549 cells by transfection of the full-length cDNA for human P450R. These P450R over-expressing cells exhibit restored sensitivity to TPZ under both aerobic and hypoxic conditions, comparable to that found in the original parental A549 cells. Further, the ability of the transfected cells to metabolize TPZ to SR4317 under hypoxic conditions is also shown to be restored. This provides further evidence that P450R can play an important role in the activation, metabolism and toxicity of this lead bioreductive drug.

Does reductive metabolism predict response to tirapazamine (SR 4233) in human non-small-cell lung cancer cell lines?

The bioreductive drug tirapazamine (TPZ, SR 4233, WIN 59075) is a lead compound in a series of potent cytotoxins that selectively kill hypoxic rodent and human solid tumour cells in vitro and in vivo. Phases II and III trials have demonstrated its efficacy in combination with both fractionated radiotherapy and some chemotherapy. We have evaluated the generality of an enzyme-directed approach to TPZ toxicity by examining the importance of the one-electron reducing enzyme NADPH:cytochrome P450 reductase (P450R) in the metabolism and toxicity of this lead prodrug in a panel of seven human non-small-cell lung cancer cell lines. We relate our findings on TPZ sensitivity in these lung lines with our previously published results on TPZ sensitivity in six human breast cancer cell lines (Patterson et al (1995) Br J Cancer 72: 1144-1150) and with the sensitivity of all these cell types to eight unrelated cancer chemotherapeutic agents with diverse modes of action. Our results demonstrate that P450R plays a significant role in the activation of TPZ in this panel of lung lines, which is consistent with previous observations in a panel of breast cancer cell lines (Patterson et al (1995) Br J Cancer 72: 1144-1150; Patterson et al (1997) Br J Cancer 76: 1338-1347). However, in the lung lines it is likely that it is the inherent ability of these cells to respond to multiple forms of DNA damage, including that arising from P450R-dependent TPZ metabolism, that underlies the ultimate expression of toxicity.

A phase II study of the modulation of 5-fluorouracil and folinic acid with high-dose infusional hydroxyurea in metastatic colorectal carcinoma

BACKGROUND

Hydroxyurea (HU), an inhibitor of ribonucleotide reductase, may potentiate the activity of 5-fluorouracil (5-FU) and folinic acid (FA) by reducing the deoxyribonucleotide pool available for DNA synthesis and repair. However as HU may inhibit the formation of 5-fluoro-2-deoxyuridine-5-monophosphate (FdUMP), one of the principal active metabolites of 5-FU, the scheduling of HU may be critical. In vitro experiments suggest that administration of HU following 5-FU, maintaining the concentration in the region of 1 mM for six or more hours, significantly enhances the efficacy of 5-FU.

PATIENTS AND METHODS

5-FU/FA was given as follows: days 1 and 2-FA 250 mg/m2 (max. 350 mg) over two hours followed by 5-FU 400 mg/m2 by intravenous bolus (i.v.b.) over 15 minutes and subsequently 5-FU 400 mg/m2 infusion (ivi) over 22 hours. HU was administered on day 3 immediately after the 5-FU with 3 g i.v.b. over 15 minutes followed by 12 g ivi over 12 hours.

RESULTS

Thirty patients were entered into the study. Median survival was nine months (range 1-51+ months). There were eight partial responses (28%, 95% CI: 13%-47%). The median duration of response was 6.5 (range 4-9 months). Grade 3-4 toxicities included neutropenia (grade 3 in eight patients and grade 4 in five), anaemia (grade 3 in one patient) and diarrhoea (grade 3 in two patients). Neutropenia was associated with pyrexia in two patients. Phlebitis at the infusion site occurred in five patients. The treatment was complicated by pulmonary embolism in one patient and deep venous thrombosis in another.

CONCLUSION

HU administered in this schedule is well tolerated. Based on these results and those of other phase II studies, a randomised phase III study of 5-FU, FA and HU versus 5-FU and FA using the standard de Gramont schedule is recommended.

Phase I study of the novel cyclic AMP (cAMP) analogue 8-chloro-cAMP in patients with cancer: toxicity, hormonal, and immunological effects

The cyclic AMP (cAMP)-dependent protein kinase regulatory subunit RI is overexpressed in cancer cells. 8-Chloro-cAMP (8-Cl-cAMP) is an RII site-specific analogue that down-regulates RI and inhibits the growth of a wide range of cancer cells in vitro and in vivo. We performed a Phase I trial of 8-Cl-cAMP in 32 patients with malignancies that were refractory to standard treatments. 8-Cl-cAMP was initially given in a 1-month cycle by constant infusion at 0.005 mg/kg/h for 21 days, followed by 1 week of rest. The dose was escalated to 0.045 mg/kg/h, but hypercalcemia became the dose-limiting toxicity. The length of drug administration was, therefore, reduced to 5 days per week for the first 3 weeks of the cycle, but it was not possible to increase the drug dose without producing hypercalcemia. Hence, the length of drug administration was reduced to 3 days per week for the first 3 weeks of the cycle. The maximum tolerated dose for this regimen was 0.15 mg/kg/h, and the dose-limiting toxicities were reversible hypercalcemia and hepatotoxicity. Stable disease for > or =4 months was observed in two patients treated at > or =0.045 mg/kg. cAMP-dependent protein kinase is involved in hormone- and cytokine-mediated signaling, and so representative hormone, cytokine, and peripheral lymphocyte subsets were measured. The drug had a parathyroid hormone-like effect on calcium homeostasis and significantly increased circulating luteinizing hormone and 17-hydoxyprogesterone levels (P < 0.02 and P < 0.0006, respectively). We conclude that 8-Cl-cAMP is well tolerated without attendant myelotoxicity, and in this study, it was associated with biological effects. In Phase II studies, a dose of 0.11 mg/kg/h for 3 days per week would be appropriate.

Phase I study of intrapleural batimastat (BB-94), a matrix metalloproteinase inhibitor, in the treatment of malignant pleural effusions

Tumor cells and associated stromal cells secrete matrix metalloproteinases (MMPs), contributing to invasion, angiogenesis, and metastasis. Batimastat (BB-94) is a broad-spectrum MMP inhibitor that causes resolution of ascites and/or tumor growth delay in animal models of breast, ovarian, and colorectal cancer. We recruited 18 patients with cytologically positive malignant pleural effusions into a Phase I study of intrapleural BB-94. Three patients received single doses of BB-94 at each dose level: 15, 30, 60, 105, 135, and 300 mg/m2. Two patients were retreated with a second course at 60 and 105 mg/m2. BB-94 was detectable in plasma 1 h after intrapleural administration, and peak levels of 20-200 ng/ml occurred after 4 h to 1 week. BB-94 persisted in the plasma for up to 12 weeks, at levels exceeding the IC50s for target MMPs. Peak values were higher, and persistence in the plasma was longer after higher doses of BB-94. The treatment was well tolerated. Toxic effects included low-grade fever for 24-48 h (6 of 18 patients, 33%) and reversible asymptomatic elevation of liver enzymes (8 patients, 44%). Toxicity seemed unrelated to BB-94 dose or plasma levels. Sixteen patients evaluable for response required significantly fewer pleural aspirations in the 3 months after BB-94 compared with the 3 months before. Seven patients (44%) required no further pleural aspiration until death/last follow-up. After 1 month, patients treated with 60-300 mg/m2 BB-94 had significantly better dyspnea scores, indicating improved exercise tolerance, compared with baseline scores the day after BB-94. The maximum tolerated intrapleural dose remains to be defined, but it is clear that intrapleural BB-94 is well tolerated, with evidence of local activity.

Enzymology of tirapazamine metabolism: a review

The enzymology of triapazamine (TPZ, SR 4233, WIN 59075, 3-amino-1,2,4-benzotriazene 1,4-dioxide, Tirazone) has been extensively studied in rodents and to a lesser extent in human systems. While it is clear that the initial reductive step in TPZ activation is enzyme-mediated, there is limited consensus in the published literature as to the relative contributions of the cellular reductases involved. Moreover, not only is the importance of subcellular localization for these putative activating reductase(s) far from clear, but their activity profiles in vivo are poorly defined. The same might also be said of the potential detoxifying enzymes. This review will attempt to establish what common ground exists regarding the enzymology of TPZ metabolism, and will relate the available evidence to the enzyme profiles found in human cell lines in vitro, as well as in xenograft models and human solid tumours.

Cyclophosphamide, methotrexate and infusional 5-fluorouracil (infusional CMF) in metastatic breast cancer

Bolus 5-fluorouracil (5-FU) is a phase-specific drug with a short plasma half-life that is used in combination with bolus cyclophosphamide and methotrexate in the treatment of breast cancer. The efficacy of 5-FU can be improved by continuous intravenous infusion using portable infusion pumps (infusional 5-FU). Infusional 5-FU, 200 mg m(-2) day(-1), in combination with standard doses of bolus cyclophosphamide and methotrexate, was evaluated in a phase I/II dose-finding study. The cyclophosphamide and methotrexate were administered in 28-day cycles as follows: cohort 1, cyclophosphamide 600 mg m(-2), days 1 and 8, and methotrexate 40 mg m(-2), day 1; cohort 2, cyclophosphamide 400 mg m(-2), days 1 and 8, and methotrexate 40 mg m(-2), day 1; cohort 3, cyclophosphamide 480 mg (m-2), days 1 and 8, and methotrexate 40 mg m(-2), day 1; cohort 4, cyclophosphamide 480 mg m(-2), days 1 and 8, and methotrexate 40 mg m(-2), days 1 and 8. Median overall survival was 10 months (range 3-21 months). Objective tumour responses were seen in 9 of 25 patients (36%, 95% CI 18-58%), including 3 of 13 patients (23%) previously treated for metastatic disease. Cohorts 1 and 4 proved to be too toxic, with five of six patients in cohort 1 and three of four in cohort 4 developing grade III/IV neutropenia. The dose intensity of cyclophosphamide achieved was as follows: cohort 1, 82%; cohort 2, 86%; cohort 3, 97%; cohort 4, 90%. Infusional 5-FU can be administered safely and is effective in combination with cyclophosphamide 480 mg m(-2), days 1 and 8, and methotrexate 40 mg m(-2), day 1, in the treatment of metastatic breast cancer.

A novel cyclic adenosine monophosphate analog induces hypercalcemia via production of 1,25-dihydroxyvitamin D in patients with solid tumors

The treatment of cancer patients with conventional chemotherapy is sometimes associated with severe systemic toxicity and only a minimal survival benefit. Because of this, new less toxic and more efficacious treatments have been sought. 8-Chloro-cAMP (8-Cl-cAMP) is one of a new generation of anticancer drugs that act at the level of signal transduction. In preclinical models, 8-Cl-cAMP modulates protein kinase A (PKA) leading to growth inhibition and increased differentiation of cancer cells. 8-Cl-cAMP was given to 16 patients with advanced cancer as an infusion via an indwelling subclavian venous catheter. We showed that 8-Cl-cAMP had a parathyroid hormone-like effect leading to increased synthesis of renal 1,25-dihydroxyvitamin D [up to 14 times the baseline value, median 3.6 times; P = 0.00001 (Student's paired t test)]. This produced the dose-limiting toxicity of reversible hypercalcemia that could not be controlled by the administration of either pamidronate or dexamethasone. The treatment was otherwise well tolerated, and other cAMP-dependent pathways (cortisol and TSH) were not affected, emphasizing the marked differences between organs in their sensitivity to this cAMP analog. Our results have shown that 8-Cl-cAMP is biologically active, and it is feasible that if the hypercalcemia can be controlled, then this drug may have a role as a single agent, or as a short infusion between cycles of chemotherapy.

A phase II study evaluating the effect of tamoxifen on DNA repair in melanoma patients treated with dacarbazine

The addition of tamoxifen to dacarbazine containing chemotherapy regimens used in the treatment of melanoma, has been shown to increase response rates, but the mechanism of any interaction is uncertain. The object of this study was to determine whether the addition of tamoxifen to dacarbazine, would modify DNA repair in-vivo and cause an increase in O6-meG adducts in peripheral blood leucocytes. This would provide some insight into the nature of the interaction between these two drugs. Twenty three patients with metastatic malignant melanoma received dacarbazine (DTIC) 1 g/m2 every three weeks for a maximum of six cycles. Tamoxifen 20 mg daily, was started after the first cycle of chemotherapy and then taken continuously during the treatment. Adduct levels after the second cycle of treatment were significantly higher than those after the first cycle (p = 0.0001). A similar rise however, was also produced when a cohort of patients were given dacarbazine without tamoxifen during the second cycle of treatment. This study did not show an additional increase of O6-meG adducts when tamoxifen was administered and therefore this mechanism does not support a postulated interaction between tamoxifen and dacarbazine. This is in agreement with the recent randomised study which did not show any significant increase in response rate with the addition of tamoxifen.

A phase II study of mitomycin C and oral etoposide for advanced adenocarcinoma of the upper gastrointestinal tract

BACKGROUND

Mitomycin C and etoposide have both demonstrated activity against gastric carcinoma. Etoposide is a topoisomerase II inhibitor with evidence for phase-specific and schedule-dependent activity.

PATIENTS AND METHOD

Twenty-eight consecutive patients with advanced upper gastrointestinal adenocarcinoma were treated with intravenous (i.v.) bolus mitomycin C 6 mg/m2 on day 1 every 21 days to a maximum of four courses. Oral etoposide capsules 50 mg b.i.d. (or 35 mg b.i.d. liquid) were administered days 1 to 10 extending to 14 days in subsequent courses if absolute neutrophil count > 1.5 x 10(9)/l on day 14 of first course, for up to six courses.

RESULTS

Twenty-six patients were assessed for response of whom 12 had measurable disease and 14 evaluable disease. Four patients had a documented response (one complete remission, three partial remissions) with an objective response rate of 15% (95% confidence interval (95% CI) 4%-35%). Eight patients had stable disease and 14 progressive disease. The median survival was six months. The schedule was well tolerated with no treatment-related deaths. Nine patients experienced leucopenia (seven grade II and two grade III). Nausea and vomiting (eight grade II, one grade III), fatigue (eight grade II, two grade III) and anaemia (seven grade II, two grade III) were the predominant toxicities.

CONCLUSION

This out-patient schedule is well tolerated and shows modest activity in the treatment of advanced upper gastrointestinal adenocarcinoma. Further studies using protracted schedules of etoposide both orally and as infusional treatment should be developed.

Palliation of inoperable esophageal carcinoma: a prospective randomized trial of laser therapy and stent placement

PURPOSE

A prospective, randomized comparison of the result of endoscopic laser therapy and that of placement of self-expandable metallic endoprostheses was performed to determine which method provides the best palliation of dysphagia in patients with inoperable esophageal carcinoma.

MATERIALS AND METHODS

Sixty patients participated in the study. Twenty-three were randomly assigned to undergo plastic-covered stent placement, 19 to undergo uncovered stent placement, and 18 to undergo laser therapy. The quality of swallowing was assessed with the dysphagia score, which ranged from 0 for normal swallowing to 4 for complete dysphagia.

RESULTS

The mean improvement in dysphagia score was 2 and ranged from -1 to 3 in patients who underwent placement of plastic-covered stents, was 2 and ranged from 0 to 4 in those who underwent placement of uncovered stents, and was 1 and ranged from 0 to 2 in those who underwent laser therapy. Six of 23 (26%) plastic-covered stents migrated, whereas none of the uncovered stents did so (P < .02). Tumor ingrowth through uncovered stents occurred in five of 19 patients (26%).

CONCLUSION

Placement of metallic esophageal endoprostheses is substantially better than endoscopic laser therapy for palliation of dysphagia in patients with inoperable esophageal carcinoma. Use of uncovered and plastic-covered metallic stents provides equal palliation in patients with dysphagia.

Overexpression of human NADPH:cytochrome c (P450) reductase confers enhanced sensitivity to both tirapazamine (SR 4233) and RSU 1069

P450 reductase (NADPH: cytochrome c (P450) reductase, EC 1.6.2.4) plays an important role in the reductive activation of the bioreductive drug tirapazamine (SR4233). Thus, in a panel of human breast cancer cell lines, expression of P450 reductase correlated with both the hypoxic toxicity and the metabolism of tirapazamine [Patterson et al (1995) Br J Cancer 72: 1144-1150]. To examine this dependence in more detail, the MDA231 cell line, which has the lowest activity of P450 reductase in our breast cell line panel, was transfected with the human P450 reductase cDNA. Isolated clones expressed a 78-kDa protein, which was detected with anti-P450 reductase antibody, and were shown to have up to a 53-fold increase in activity of the enzyme. Using six stable transfected clones covering the 53-fold range of activity of P450 reductase, it was shown that the enzyme activity correlated directly with both hypoxic and aerobic toxicity of tirapazamine, and metabolism of the drug under hypoxic conditions. No metabolism was detected under aerobic conditions. For RSU1069, toxicity was also correlated with P450 reductase activity, but only under hypoxic conditions. Measurable activity of P450 reductase was found in a selection of 14 primary human breast tumours. Activity covered an 18-fold range, which was generally higher than that seen in cell lines but within the range of activity measured in the transfected clones. These results suggest that if breast tumours have significant areas of low oxygen tension, then they are likely to be highly sensitive to the cytotoxic action of tirapazamine and RSU 1069.