Phase II study of CPT-11, a new camptothecin derivative, in metastatic colorectal cancer. CPT-11 Gastrointestinal Cancer Study Group

Kampo medicine "Dai-kenchu-to" prevents CPT-11-induced small-intestinal injury in rats

PURPOSE

The key anticancer agent, CPT-11 (irinotecan hydrochloride), induces severe diarrhea clinically. We investigated the effect of a Kampo medicine, Dai-kenchu-to (DKT), on CPT-11-induced intestinal injuries in rats.

METHODS

Twenty-four male Wistar rats were divided into three groups: a control group; a CPT-11 group, given CPT-11 150 mg/kg intraperitoneally for 2 days; and a DKT group, given DKT 300 mg/kg orally for 5 days with CPT-11 150 mg/kg intraperitoneally on days 4 and 5. The rats were killed on day 6.

RESULTS

Interleukin (IL)-1β, IL-12, interferon (IFN)-γ, and tumor necrosis factor-α expression in the small intestine of the CPT-11 group was significantly higher than that of the control group. Interleukin-1β and IFN-γ expression was improved significantly by DKT (P < 0.05). The number and height of jejuna villi, injury score, and apoptosis index in the CPT-11 group were improved significantly by DKT (P < 0.05).

CONCLUSIONS

DKT suppressed CPT-11 induced inflammatory cytokines and apoptosis in the intestinal mucosa and maintained the mucosal integrity.

Sensitivity to previous irinotecan treatment does not predict the efficacy of combination chemotherapy with cetuximab plus irinotecan for wild-type KRAS metastatic colorectal cancer

The aim of this study was to evaluate the association of sensitivity to previous irinotecan-based chemotherapy with efficacy of cetuximab plus irinotecan therapy in metastatic colorectal cancer (MCRC) patients with wild-type KRAS. We analysed a pooled data set consisting of data from 87 MCRC patients from two previous phase II studies (n=60) and a group given off-protocol treatment (n=27) following irinotecan-, oxaliplatin-, and fluoropyrimidine-based chemotherapy. Overall objective response rate to cetuximab plus irinotecan was 28.7%, median progression-free survival (PFS) was 5.3 months, and median overall survival was 12.2 months. Objective response rate did not significantly differ between patients with a favourable response to previous irinotecan (n=23), stable disease (n=38), or progressive disease (n=26), with observed rates of 29.2%, 31.6%, and 23.1%, respectively. Additionally, the non-parametric Spearman rank correlation coefficients (ρ) between the PFS of previous irinotecan-based chemotherapy and that of cetuximab plus irinotecan were quite low (ρ=0.067 and 0.057 in patients with previous irinotecan as first- and second-line therapies, respectively). Although exploratory nature and small sample size may be limitations of this study, these findings indicate that the efficacy of irinotecan plus cetuximab in MCRC patients with wild-type KRAS did not differ by previous sensitivity to irinotecan.

Circulating endothelial progenitor cells in metronomic chemotherapy using irinotecan and/or bevacizumab for colon carcinoma: Study of their clinical significance

The aim of the present study was to clarify the antitumor efficacy of metronomic chemotherapy using irinotecan (CPT-11) combined with or without bevacizumab against colon cancer, and the significance of circulating endothelial cell (CECs) and endothelial progenitor cells (CEPs) as a surrogate marker for metronomic chemotherapy. KM12SM cells were implanted into the subcutis of nude mouse. After confirming that the implanted tumors had grown 5 mm in size, group A received an intraperitoneal injection of 40 mg/kg CPT-11 every two weeks for 4 weeks [conventional maximum-tolerated dose (MTD)], group B received 10 mg/kg twice weekly (metronomic), group C received 10 mg/kg twice weekly combined with 5 mg/kg bevacizumab twice weekly (metronomic + anti-angiogenic), and the control group received 0.2 ml of PBS every week. Serial changes of CECs and CEPs in peripheral blood and microvessel density (MVD) in the tumor tissues were evaluated. The results showed that the antitumor activity in group B and in group C was significantly higher than that in group A. A significant inhibition in CEPs on day 15 in the metronomic therapy groups B and C was noted when compared to that in the control group, while there was no significant difference in CECs and CEPs between the groups on days 4 and 8. The MVD on day 15 in metronomic groups was significantly lower than that in group A. In conclusion, metronomic chemotherapy of CPT-11 with or without bevacizumab for colon cancer was more effective than the MTD therapy via anti-angiogenic effects. Sequential measurement of CEPs may be a predictive factor for the efficacy and a decisive factor for the optimal dose of metronomic therapy in colon cancer.

A randomized phase III trial of adjuvant chemotherapy with irinotecan, leucovorin and fluorouracil versus leucovorin and fluorouracil for stage II and III colon cancer: a Hellenic Cooperative Oncology Group study

BACKGROUND

Colon cancer is a public health problem worldwide. Adjuvant chemotherapy after surgical resection for stage III colon cancer has been shown to improve both progression-free and overall survival, and is currently recommended as standard therapy. However, its value for patients with stage II disease remains controversial. When this study was designed 5-fluorouracil (5FU) plus leucovorin (LV) was standard adjuvant treatment for colon cancer. Irinotecan (CPT-11) is a topoisomerase I inhibitor with activity in metastatic disease. In this multicenter adjuvant phase III trial, we evaluated the addition of irinotecan to weekly 5FU plus LV in patients with stage II or III colon cancer.

METHODS

The study included 873 eligible patients. The treatment consisted of weekly administration of irinotecan 80 mg/m2 intravenously (i.v.), LV 200 mg/m2 and 5FU 450 mg/m2 bolus (Arm A) versus LV 200 mg/m2 and 5FU 500 mg/m2 i.v. bolus (Arm B). In Arm A, treatments were administered weekly for four consecutive weeks, followed by a two-week rest, for a total of six cycles, while in Arm B treatments were administered weekly for six consecutive weeks, followed by a two-week rest, for a total of four cycles. The primary end-point was disease-free survival (DFS) at three years.

RESULTS

The probability of overall survival (OS) at three years was 0.88 for patients in Arm A and 0.86 for those in Arm B, while the five-year OS probability was 0.78 and 0.76 for patients in Arm A and Arm B, respectively (P = 0.436). Furthermore, the probability of DFS at three years was 0.78 and 0.76 for patients in Arm A and Arm B, respectively (P = 0.334). With the exception of leucopenia and neutropenia, which were higher in patients in Arm A, there were no significant differences in Grades 3 and 4 toxicities between the two regimens. The most frequently recorded Grade 3/4 toxicity was diarrhea in both treatment arms.

CONCLUSIONS

Irinotecan added to weekly bolus 5FU plus LV did not result in improvement in disease-free or overall survival in stage II or III colon cancer, but did increase toxicity.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12610000148077.

Phase I/II study of a 3-week cycle of irinotecan and S-1 in patients with advanced colorectal cancer

The combination of an oral fluoropyrimidine derivative, S-1, and irinotecan is expected to be a promising regimen for advanced colorectal cancer. This study was performed to determine the maximum tolerated dose (MTD) and recommended dose (RD) of irinotecan combined with S-1 in a 3-week cycle regimen and to observe the safety and efficacy for patients with previously untreated advanced colorectal cancer. Eighty milligrams per m(2) of S-1 was given orally for 14 consecutive days and escalated doses of irinotecan were administered on days 1 and 8 every 3 weeks in the phase I trial. Forty patients were treated at the RD during the phase II trial. Forty-three patients were enrolled between February 2005 and March 2007. The dose-limiting toxicity was diarrhea and abdominal pain. The MTD of irinotecan was 100 mg/m(2) and the RD was determined to be 80 mg/m(2) of irinotecan combined with 80 mg/m(2) of S-1. The phase II trial showed that 22 of 40 patients achieved a complete or partial response and eight had stable disease. The overall response rate was 55.0%. The median progression-free survival time and median survival time were 6.7 and 21 months, respectively. There were no treatment-related deaths. The main toxicities were leukopenia, neutropenia, anorexia and diarrhea. This study suggests the combination of irinotecan and S-1 repeated every 3 weeks is tolerable and effective for patients with previously untreated advanced colorectal cancer.

Phase 1/2 clinical study of irinotecan and oral S-1 (IRIS) in patients with advanced gastric cancer

BACKGROUND

Irinotecan and S-1, an oral fluoropyrimidine composed of tegafur, gimeracil, and oteracil potassium, have demonstrated antitumor activity against advanced gastric cancer. We performed a phase 1/2 study to determine the recommended dose, antitumor activity, and safety of a combination of S-1 and irinotecan in patients with advanced gastric cancer.

METHODS

Patients with previously untreated advanced gastric cancer were enrolled. Patients received irinotecan intravenously on days 1 and 15 plus oral S-1 twice daily on days 1-14 of a 28-day cycle. In the phase 1 part, the dose of irinotecan was escalated from 100 mg/m(2) to 125 mg/m(2) and then to 150 mg/m(2).

RESULTS

A total of 24 patients were enrolled. Overall, the median number of treatment cycles per patient was 5.9, and 92% of the patients completed at least two cycles. The overall response rate was 54.2% (13 of 24). The response rates in differentiated and undifferentiated cancer were 56.3% (nine of 16) and 50.0% (four of eight), respectively. Median survival time was 581 days. The maximum tolerated dose of irinotecan was not reached at the highest level. However, grade 4 neutropenia occurred at 125 mg/m(2). We concluded that the recommended dose of irinotecan for the present regimen was 125 mg/m(2).

CONCLUSION

Treatment with S-1+irinotecan is considered effective in patients with advanced gastric cancer who have not previously received chemotherapy. A combination of irinotecan and S-1 was well tolerated in patients with advanced gastric cancer and could be given on an outpatient basis.

Streptomycin alleviates irinotecan-induced delayed-onset diarrhea in rats by a mechanism other than inhibition of β-glucuronidase activity in intestinal lumen

Irinotecan hydrochloride (CPT-11) is a useful drug for cancer chemotherapy but sometimes induces severe diarrhea clinically. CPT-11 is mainly activated to SN-38 by carboxylesterase (CES) and then detoxified to SN-38 glucuronide (SN-38G) by UDP-glucuronosyltransferase (UGT) in the liver. SN-38G is excreted via bile and de-conjugated to SN-38 by β-glucuronidase (β-GLU) in the intestinal content. In order to clarify the alleviative effect of antibiotics on CPT-11-induced diarrhea, we examined whether penicillin G and streptomycin (SM) alleviate CPT-11-induced delayed-onset diarrhea using three diarrheal models, i.e., Wistar rats with repeated dosing of CPT-11 (60 mg/kg/day i.v. for 4 consecutive days) and Wistar and Gunn rats with a single dosing of CPT-11 (200 and 20 mg/kg i.v., respectively). Gunn rats have an inherited deficiency of UGT1A and cannot conjugate SN-38 to SN-38G. Therefore, onset of CPT-11-induced diarrhea in Gunn rats is not affected by β-GLU activity. SM alleviated diarrhea in all three diarrheal models. The alleviation of diarrhea by SM in Gunn rats indicated that the effect of SM occurred by a mechanism other than the inhibition of β-GLU activity. SM decreased CPT-11 and/or SN-38 concentrations in intestinal tissues and alleviated epithelial damage from the ileum to colon. SM did not inhibit β-GLU activity in the cecal content. SM also inhibited the intestinal absorption of CPT-11 and decreased CES activity and increased UGT activity in the intestinal epithelium. These findings indicated that SM decreased the exposure of CPT-11 and SN-38 to the intestinal epithelium by inhibiting the absorption of CPT-11 from the intestinal lumen and the change of CES and UGT activities in the intestinal epithelium and alleviated delayed-onset diarrhea.

Dosage escalation study of S-1 and irinotecan in metronomic chemotherapy against advanced colorectal cancer

The anti-angiogenic efficacy of chemotherapy would seem to be optimized by administering comparatively lower doses of drugs on a more frequent (daily, several times a week, or weekly) or continuous schedule, with no extended interruptions - sometimes referred to as 'metronomic' chemotherapy. This phase I study was performed to determine the recommended dosage (RD) of metronomic chemotherapy using oral fluoropyrimidine S-1 plus weekly irinotecan (CPT-11) in patients with previously untreated advanced or recurrent colorectal cancer. Patients received first-line chemotherapy consisting of 80 mg/m(2) of S-1 given on days 3 to 7, 10 to 14, and 17 to 21 with escalating dosages of CPT-11 (from 40 mg/m(2)) administered intravenously on day 1, 8, and 15 of a 28-day cycle. Standard patient eligibility criteria were used. Based on the concept of metronomic chemotherapy, dose limiting toxicity (DLT) was defined any toxicity that resulted in skipping of CPT-11 administration, or more than 5 days suspension in S-1 administration, in addition to the conventional criteria. If the maximum tolerated dosage (MTD) was defined as the maximum dosage at which no suspension of CPT-11 or S-1 administration occurred, the RD was considered to be the dosage one rank lower than the MTD. On the other hand, in the present study the MTD was defined as the dosage at which at least one suspension of CPT-11 or S-1 administration occurred, the MTD was considered to be the RD. Two of the first 3 patients at level 4 received 60 mg/m(2) of CPT-11 and 80 mg/m(2) of S-1 experienced a suspension in CPT-11 administration, thus level 4 was defined as the MTD and RD. Sixty mg/m(2) of CPT-11 and 80 mg/m(2) of S-1 were the indicated RD for the following phase II study of metronomic chemotherapy.

Irinotecan and its active metabolite, SN-38: review of bioanalytical methods and recent update from clinical pharmacology perspectives

The introduction of irinotecan has revolutionized the applicability of camptothecins as predominant topoisomerase I inhibitor for anti-cancer therapy. The potent anti-tumor activity of irinotecan is due to rapid formation of an in vivo active metabolite, SN-38. Therefore, irinotecan is considered as a pro-drug to generate SN-38. Over the past decade, side-by-side with the clinical advancement of the use of irinotecan in the oncology field, a plethora of bioanalytical methods have been published to quantify irinotecan, SN-38 and other metabolites. Because of the availability of HPLC, LC-MS and LC-MS/MS methods, the pharmacokinetic profiling of irinotecan and its metabolites has been accomplished in multiple species, including cancer patients. The developed assays continue to find use in the optimization of newly designed delivery systems with regard to pharmacokinetics to promote safe and effective use of either irinotecan or SN-38. This review intends to: firstly, provide an exhaustive compilation of the published assays for irinotecan, SN-38 and other metabolite(s) of irinotecan, as applicable; secondly, to enumerate the validation parameters and applicable conclusions; and thirdly, provide some recent perspectives in the clinical pharmacology arena pertaining to efflux transporters, pediatric profiling, role of kidney function in defining toxicity, drug-drug interaction potential of irinotecan, etc.

Vascular Endothelial Growth Factor plus Epidermal Growth Factor Receptor Dual Targeted Therapy in Metastatic Colorectal Cancer: Synergy or Antagonism?

There has been an intensive effort to develop novel therapies for the treatment of metastatic colorectal cancer (mCRC). The anti-epidermal growth factor receptor (EGFR) antibodies panitumumab and cetuximab and the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab have demonstrated clinical efficacy and acceptable toxicity in the treatment of mCRC as single agents or in combination with chemotherapy. Recent clinical trials have explored the efficacy and safety of treatment regimens incorporating chemotherapy in combination with bevacizumab and either panitumumab or cetuximab in patients with mCRC. Results from the BOND-2 trial, which investigated cetuximab, bevacizumab, and chemotherapy in mCRC, provided support for this therapeutic approach. Two large randomized phase 3 trials were initiated to evaluate firstline treatment of mCRC. The Panitumumab Advanced Colorectal Cancer Evaluation (PACCE) study investigated the efficacy and safety of oxaliplatin- or irinotecan-based chemotherapy and bevacizumab with or without panitumumab; CAIRO2 assessed the efficacy and safety of capecitabine/oxaliplatin and bevacizumab with or without cetuximab. In both trials, the combination of bevacizumab, an EGFR-specific antibody, and chemotherapy in first-line treatment of mCRC was associated with increased toxicity and no improvement in patient outcome. These results suggest that these specific combinations should not be used in first-line mCRC outside investigational studies.

Target Practice: Figuring Out Which, When, and Why to Use Systemic Therapies for Metastatic Colon Cancer

There have been many recent advances in the field of systemic chemotherapy for metastatic colorectal cancer. Each treatment affects a different target, including thymidylate synthase, topoisomerase, DNA, the epidermal growth factor receptor, and vascular endothelial growth factor. These treatments have been used in multiple combinations, schedules, and as first-line, second-line, and third-line therapies. The current clinical trials reported can help guide the clinician to determine the appropriate timing, combination, and schedule of chemotherapy agents. Although the decision regarding colorectal cancer chemotherapy is now more complicated, our patients have certainly benefited from better response rates and most importantly, longer survival times.

Salvage therapy for liver-dominant colorectal metastatic adenocarcinoma: comparison between transcatheter arterial chemoembolization versus yttrium-90 radioembolization

PURPOSE

To compare transarterial chemoembolization (CE) versus yttrium-90 ((90)Y) radioembolization (RE) for liver-dominant metastatic colorectal adenocarcinoma as salvage therapy.

MATERIALS AND METHODS

Of 36 patients, 21 underwent CE (37 procedures; 11 men; mean age, 67 years; 16 with Child-Pugh class A disease) and 15 underwent (90)Y RE (19 procedures; 11 men; mean age, 64 years; 13 with Child-Pugh class A disease) for liver-dominant colorectal adenocarcinoma. Mean index dominant lesion sizes were 9.3 cm and 8.2 cm in the CE and RE groups, respectively. Multilobar disease was seen in 67% and 87% of the respective groups, and extrahepatic metastases were seen in 43% and 33%, respectively. Mean times from diagnosis of liver metastasis to CE or RE were 17.6 months and 22.6 months, respectively.

RESULTS

A total of 37 CE procedures with cisplatin, doxorubicin, and mitomycin were performed, and 19 RE procedures with (90)Y were performed; 43% of patients in the CE group and 20% in the RE group received multiple treatment sessions, and 100% of procedures were technically successful. Median survival times were 7.7 months for the CE group and 6.9 months for the RE group (P = .27). The 1-, 2-, and 5-year survival rates were 43%, 10%, and 0%, respectively, in the CE group; and 34%, 18%, and 0%, respectively, in the RE group. There was one major complication (2.7%) in the CE group (pulmonary embolism), with a 30-day mortality rate of 5.4% (n = 2). There were no major complications in the RE group, with a 30-day mortality rate of 5.2% (n = 1).

CONCLUSIONS

Patients with unresectable liver colorectal metastases that progress despite systemic chemotherapy can undergo palliative treatment with CE or RE with similar survival benefit.

Effects of breast cancer resistance protein inhibitors and pharmaceutical excipients on decreasing gastrointestinal toxicity of camptothecin analogs

AIM

To investigate the effect of breast cancer resistance protein (BCRP) inhibitors and pharmaceutical excipients on reducing the biliary excretion of camptothecins (CPT), ameliorating delayed-type diarrhea and intestinal mucosa damage induced by CPT.

METHODS

The cumulative biliary excretion of irinotecan (CPT-11) and hydroxycamptothecin (HCPT) with or without BCRP inhibitors and excipients was investigated in rats. The gastrointestinal toxicity, assessed as the diarrheal score, body weight change and microscopic pathological damage was also determined in rats.

RESULTS

Breast cancer resistance protein (BCRP) exhibited important effects on the biliary excretion of CPT. Coadministration of BCRP inhibitors such as GF120918 and cyclosporin A reduced the biliary excretion of CPT-11 and HCPT. Pharmaceutical excipients such as Pluronic F68 and PEG 2000 stearate also showed inhibitory effects on BCRP and similarly reduced CPT biliary excretion. The observed gastrointestinal toxicity was ameliorated by coadministration of BCRP inhibitors and excipients compared with injection of CPT-11 and HCPT alone.

CONCLUSION

The use of excipients as inhibitors of BCRP is safe and relatively non-toxic, and may lead to important pharmacotherapeutic benefits by decreasing the gastrointestinal toxicity of CPT.

Dose escalation study of amrubicin in combination with fixed-dose irinotecan in patients with extensive small-cell lung cancer

BACKGROUND

The combination of amrubicin (Am) and irinotecan (CPT) shows appreciable activity against small-cell lung cancer (SCLC) in vitro.

PATIENTS AND METHODS

We conducted a dose escalation study of Am in combination with CPT to determine the qualitative and quantitative toxicities and efficacy against extensive (ED) SCLC.

RESULTS

Thirteen previously untreated patients with ED-SCLC were treated with CPT at 60 mg/m(2) on day 1 and dose-escalated Am on days 1-3 with prophylactic granulocyte colony-stimulating factor subcutaneously on days 5-9 every 2-3 weeks. At level 3 (40 mg/m(2)/day Am), 3 of 4 registered patients experienced dose-limiting toxicity such as grade 4 neutropenic fever, and therefore, this was defined as the maximum tolerated dose. A total of 31 courses was administered at dose level 2 (35 mg/m(2)/day) in 6 patients, and grade 4 neutropenia was observed during 5 courses (16.1%). Non-hematological toxicities, except 1 course of grade 3 transfusion of red blood cells and 1 course of grade 3 transaminase elevation, were mild. Thus, dose level 2 of Am was recommended for further study. One patient achieved complete remission and 12 achieved partial remission, and the overall response rate was 100%. The median survival time was 17.4 months, and the 1-year survival rate was 76.9%.

CONCLUSIONS

CPT at 60 mg/m(2) on day 1 and Am at 35 mg/m(2)/day on days 1-3 with granulocyte colony-stimulating factor support every 3 weeks is recommended for Japanese patients with ED-SCLC.

Combination chemotherapy of biweekly irinotecan (CPT-11) plus tegafur/uracil (UFT) and leucovorin (LV) for patients with metastatic colorectal cancer: phase I/II study in Japanese patients

PURPOSE

We aimed to evaluate the safety and efficacy of combination chemotherapy with biweekly irinotecan (CPT-11) plus oral tegafur/uracil (UFT) and leucovorin (LV) in patients with previously untreated metastatic colorectal adenocarcinoma in phase I/II setting.

PATIENTS AND METHODS

We recruited 37 patients with histologically proven metastatic colorectal adenocarcinoma. UFT (300 mg/m(2) per day) and LV (75 mg/day) were administered orally on days 1-21. CPT-11 was administered intravenously on day 1 and 15, at an initial dose of 60 mg/m(2), stepping up to 150 mg/m(2) in a traditional phase I fashion. The treatment was repeated every 4 weeks. After patients enrolled into a phase II portion, the efficacy and toxicity of this regimen were also assessed.

RESULTS

The recommended dose of CPT-11 was determined to be 150 mg/m(2). Although one patient had a pulmonary embolism after 60 mg/m(2) of CPT-11, the treatment was well tolerated in general. The overall objective response rate was 37.8% (14/37; 95% CI, 22.5-55.2) in all patients. Median progression-free survival was 226 days (95% CI, 133-276).

CONCLUSIONS

Biweekly CPT-11 plus UFT and LV had a reasonable safety profile with manageable toxicity, and had a promising activity in patients with metastatic colorectal cancer. Further trials are indicated based on the promising results observed in this study.

A general review of the role of irinotecan (CPT11) in the treatment of gastric cancer

BACKGROUND

The prognosis of gastric tumor is generally poor because most tumors are diagnosed at an advanced stage. Chemotherapy has a proven palliative role in advanced gastric cancer and several combination regimens were explored in the last 10 yr. Nevertheless, none of them showed a convincing improvement resulting in an enhancement of response rate and overall survival without discrimination of the quality of life. Irinotecan (CPT11) has been evaluated in multiple trials alone or in combined therapy with promising results and good tolerance. Thus, a review of the importance and impact of CPT11 in this indication is detailed.

METHODS

This article reviews the evidence for the use of CPT11 in the treatment of gastric cancer based on a computerized MEDLINE search of literature published until August 2006 leading to a total of 91 publications.

RESULTS

CPT11 was frequently used and showed a good response rate varying from 14% to 23% as single agent and 45% to 70% in combination with a median time to progression of 3 mo in single agent and 4-6 mo in combination, and median overall survival of approx 7 mo in single agent and up to 10.58 mo in combination.

CONCLUSION

The overall response of irinotecan-based chemotherapy in advanced gastric cancer was shown to be as effective as other combined chemotherapy. The hematological and digestive toxicity were tolerable and mild, especially in weekly regimen. Thus, irinotecan-based chemotherapy should be considered as one of the preferred choices in front line chemotherapy in advanced gastric cancer.

Phase I study of S-1 combined with irinotecan (CPT-11) in patients with advanced colorectal cancer

PURPOSE

To determine the maximum tolerated dose, recommended dose and dose-limiting toxicities of irinotecan plus S-1 in advanced colorectal cancer.

PATIENTS AND METHODS

S-1 was administered orally at 80 mg/m2/day for 21 consecutive days followed by a 2-week rest. CPT-11 was given intravenously on days 1 and 15 of each course, at an initial dose of 60 mg/m2/day, stepping up to 80, 100, 120 or 140 mg/m2/day. Courses were repeated every 5 weeks, unless disease progression or severe toxicities were observed.

RESULTS

A total of 20 patients were entered in this study. The maximum tolerated dose of CPT-11 was considered to be 100 mg/m2, because 2 of 3 patients developed dose-limiting toxicities, such as anorexia, fatigue and diarrhea. Therefore, the recommended dose of CPT-11 was set at 80 mg/m2. Tumor responses were seen in 8 of 14 patients with measurable lesions.

CONCLUSION

A combination of S-1 with CPT-11 is safe and can be recommended for further phase II studies in patients with advanced colorectal cancer.

Irinotecan fluorouracil plus leucovorin is not superior to fluorouracil plus leucovorin alone as adjuvant treatment for stage III colon cancer: results of CALGB 89803

PURPOSE

Randomized studies have shown that irinotecan (CPT-11) extends survival in metastatic colorectal cancer patients when administered in second-line and when added to fluorouracil (FU) plus leucovorin (LV) in first-line therapy of metastatic colorectal cancer. When this study was initiated, FU plus LV was standard adjuvant treatment for stage III colon cancer. We evaluated the efficacy and safety of weekly bolus CPT-11 plus FU plus LV in the treatment of patients with completely resected stage III colon cancer.

METHODS

A total of 1,264 patients were randomly assigned to receive either standard weekly bolus FU plus LV regimen or weekly bolus CPT-11 plus FU plus LV. The primary end points of the study were overall survival (OS) and disease-free survival (DFS).

RESULTS

Treatment arms were well-balanced for patient characteristics and prognostic variables. There were no differences in either DFS or OS between the two treatment arms. Toxicity, including lethal toxicity, was significantly higher on the CPT-11 plus FU plus LV arm.

CONCLUSION

The addition of CPT-11 to weekly bolus FU plus LV did not result in improvement in DFS or OS in stage III disease, but did increase both lethal and nonlethal toxicity. This trial demonstrates that advances in the treatment of metastatic disease do not necessarily translate into advances in adjuvant treatment, and it reinforces the need for randomized controlled adjuvant studies.

Lopinavir–Ritonavir Dramatically Affects the Pharmacokinetics of Irinotecan in HIV Patients With Kaposi’s Sarcoma

The coadministration of protease inhibitors with anticancer drugs in the management of human immunodeficiency virus-related malignancies can cause potential drug-drug interactions. The effect of lopinavir/ritonavir (LPV/RTV) on the pharmacokinetics of irinotecan (CPT11) has been investigated in seven patients with Kaposi's sarcoma. Coadministration of LPV/RTV reduces the clearance of CPT11 by 47% (11.3+/-3.5 vs 21.3+/-6.3 l/h/m(2), P=0.0008). This effect was associated with an 81% reduction (P=0.02) of the AUC (area under the curve) of the oxidized metabolite APC (7-ethyl-10-[4-N-(5-aminopentanoic-acid)-1-piperidino]-carbonyloxycamptothecin). The LPV/RTV treatment also inhibited the formation of SN38 glucuronide (SN38G), as shown by the 36% decrease in the SN38G/SN38 AUCs ratio (5.9+/-1.6 vs 9.2+/-2.6, P=0.002) consistent with UGT1A1 inhibition by LPV/RTV. This dual effect resulted in increased availability of CPT11 for SN38 conversion and reduced inactivation on SN38, leading to a 204% increase (P=0.0001) in SN38 AUC in the presence of LPV/RTV. The clinical consequences of these substantial pharmacokinetic changes should be investigated.

Involvement of UDP-glucuronosyltransferase activity in irinotecan-induced delayed-onset diarrhea in rats

We assessed the involvement of UDP-glucuronosyltransferase (UGT) activity in episodes of irinotecan hydrochloride (CPT-11)-induced delayed-onset diarrhea using a mutant rat strain with an inherited deficiency of UGT1A (Gunn rats). Gunn rats exhibited severe diarrhea after the intravenous administration of CPT-11 at a dose of 20 mg/kg, whereas Wistar rats did not. In the epithelium of the small intestine and cecum in Gunn rats, the shortening of villi, degeneration of crypts, and destruction of the nucleus were observed. The AUC, MRT, and t (1/2) of CPT-11, and the AUC of 7-ethyl-10-hydroxycamptothecin (SN-38) in plasma were, respectively, 1.6-fold, 1.5-fold, 1.7-fold, and 6.5-fold higher, and the cumulative biliary excretion rate of SN-38 was 2.3-fold higher, in Gunn rats than Wistar rats. SN-38 glucuronide excreted via bile in Wistar rats was not de-conjugated in the small intestinal lumen. The SN-38 AUC values in small intestinal tissues were also 5.0 to 5.8-fold higher in Gunn rats than Wistar rats. In conclusion, Gunn rats developed severe delayed-onset diarrhea after i.v. administration of CPT-11 at a much lower dose. Severe intestinal impairments would be induced in Gunn rats through exposure to SN-38 at high levels for a long period mainly via the intestinal lumen and partially via the bloodstream. These results clarified that the deficiency of UGT activity contributed greatly to the induction of the CPT-11-induced delayed-onset diarrhea and epithelial impairment in the intestine. In the clinic, great care is needed when using chemotherapy with CPT-11 in patients with poor UGT activity.

A phase II study of irinotecan in combination with doxifluridine, an intermediate form of capecitabine, in patients with metastatic colorectal cancer

The purpose of this study was to examine the efficacy of a combination treatment of sequential irinotecan and doxifluridine, an intermediate of capecitabine, evaluated by the response rate and safety in patients with metastatic colorectal cancer. In all, 60 metastatic colorectal cancer patients with measurable disease were enrolled. The schedule of the treatment consisted of a 90 min intravenous (IV) infusion of irinotecan 150 mg/m2 for on days 1 and 15, and 600-1,000 mg/body of oral doxifluridine on days 3-14 and 17-28. Cycles were repeated every 35 days. A median of three cycles of the combination therapy (range 1-14 cycles) was administered. A total of 57 patients (95%) completed at least two cycles of the therapy without any dose reductions. There was one complete response and 23 partial responses with an overall response rate of 40% [95% confidence interval (CI): 28-53%]. A total of 19 patients had stable disease, 43(72%) achieved disease control. The median time to progression was 5.9 months and the median overall survival was 20.5 months. Ten (17%) and 17 (28%) patients developed Grade 3-4 leukopenia and neutropenia, respectively. Grade 3-4 fatigue was observed in 7(12%) patients, nausea in five (8%), vomiting in four (7%), and diarrhea,in three (5%) patients. No treatment-related deaths were noted during the study. From these results, the combination of sequential irinotecan and doxifluridine is considered to be an effective, easy-to-administer regimen with acceptable tolerability.

Preliminary results of phase I trial of oral uracil/tegafur (UFT), leucovorin plus irinotecan and radiation therapy for patients with locally recurrent rectal cancer

BACKGROUND

Surgical attempts for locally recurrent rectal cancer often fail due to local re-recurrence and distant metastasis. Preoperative chemoradiation may enhance better local control and survival. The aim of this study was to assess the safety of oral uracil and tegafur (UFT) plus leucovorin (LV), and irinotecan combined with radiation and determine the maximum-tolerated dose (MTD) and dose limiting toxicity (DLT) of the triple drug regimen.

PATIENTS AND METHODS

Patients with locally recurrent rectal cancer received escalating doses of irinotecan on days 1, 8, 15, and 22 (starting at 30 mg/m2, with 10 mg increments between consecutive cohorts) and fixed doses of UFT (300 mg/m2) plus LV (75 mg/day) on days 3 to 7, 10 to 14, 17 to 21, and 24 to 28. Radiation was given 5 days per week totaling 40 to 50 Gy (2Gy/day).

RESULTS

Six patients were treated at the starting dose, and 2 received the full scheduled chemoradiotherapy. The other 4 patients had grade 3 diarrhea and diarrhea was the DLT. One patient had partial response and he had subsequently radical surgical resection. Median progression free survival for local recurrence was 320 days.

CONCLUSION

Irinotecan plus UFT/LV with concomitant radiotherapy in patients with locally recurrent rectal cancer was not feasible due to diarrhea in this setting. Modification of the treatment is needed.

The synergism between Belotecan and cisplatin in gastric cancer

PURPOSE

We wanted to demonstrate the anti-cancer effect and interaction between belotecan and cisplatin on gastric cancer cell line and we evaluated the mechanisms of this synergistic effect in vitro.

MATERIALS AND METHODS

The growth inhibitory effect of belotocan and cisplatin against several gastric cancer cell lines (SNU-5, SNU-16 and SNU-601) was estimated by tetrazolium dye assay. The effect of a combination treatment was evaluated by the isobologram method. The biochemical mechanisms for the interaction between the drugs were analyzed by measuring the formation of DNA interstrand cross-links (ICLs) and DNA topo-I activity.

RESULTS

Belotecan showed synergism with cisplatin for growth inhibitory effect on the gastric cancer cell lines SNU-5, and SNU-16, but this was subadditive on the SNU-601 cell line. The formation of DNA ICLs in SNU-16 cells by cisplatin was increased by combination with belotecan, but this was not affected in SNU-601 cells. The topo-I inhibition by belotecan was enhanced at high concentrations of cisplatin in SNU-16, but not in SNU-601 cells.

CONCLUSION

Belotecan and cisplatin show various combination effect against gastric cancer cells. The synergism between cisplatin and belotecan could be the result of one of the following mechanisms: the modulating effect of belotecan on the repair of cisplatin-induced DNA adducts and the enhancing effect of cisplatin on the belotecan-induced topo-I inhibitory effect.

A phase II study of weekly irinotecan as first-line therapy for patients with metastatic pancreatic cancer

PURPOSE

The aim of this study was to assess the efficacy and toxicity of weekly irinotecan in patients with metastatic pancreatic cancer.

PATIENTS AND METHODS

Patients with histologically proven pancreatic adenocarcinoma, at least one bidimensionally measurable metastatic lesion, and no prior chemotherapy were selected. Irinotecan at a dose of 100 mg/m2 was administered intravenously for 90 min on days 1, 8, and 15 every 4 weeks until disease progression or unacceptable toxicity. Pharmacokinetics was examined on day 1 of the first cycle of treatment.

RESULTS

Thirty-seven of 40 enrolled patients were assessable for efficacy and toxicity. A partial response was obtained in 10 patients, giving an overall response rate of 27.0% (95% confidence interval 13.8-44.1%). The median overall survival was 7.3 months with a 1-year survival rate of 29.5%. Although toxicities were generally tolerated, one patient died of disseminated intravascular coagulation syndrome induced by neutropenia with watery diarrhea. Pharmacokinetic study showed that patients with biliary drainage seemed to have higher area under the concentration versus time curve for irinotecan and its metabolites compared with patients without biliary drainage.

CONCLUSION

Single-agent irinotecan has significant efficacy for metastatic pancreatic cancer. The toxicity with this schedule appears manageable, though it must be monitored carefully.

90Y microsphere (TheraSphere) treatment for unresectable colorectal cancer metastases of the liver: response to treatment at targeted doses of 135-150 Gy as measured by [18F]fluorodeoxyglucose positron emission tomography and computed tomographic imaging

PURPOSE

The purpose of this phase II study was to determine the safety and efficacy of TheraSphere treatment (90Y microspheres) in patients with liver-dominant colorectal metastases in whom standard therapies had failed or were judged to be inappropriate.

MATERIALS AND METHODS

Twenty-seven patients with unresectable hepatic colorectal metastases were treated at a targeted absorbed dose of 135-150 Gy. Safety and toxicity were assessed according to the National Cancer Institute's Common Toxicity Criteria, version 3.0. Response was assessed with use of computed tomography (CT) and was correlated with response on [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET). Survival from first treatment was estimated with use of the Kaplan-Meier method.

RESULTS

Tumor response measured by FDG PET imaging exceeded that measured by CT imaging for the first (88% vs 35%) and second (73% vs 36%) treated lobes. Tumor replacement of 25% or less (vs >25%) was associated with a statistically significant increase in median survival (339 days vs 162 days; P = .002). Treatment-related toxicities included mild fatigue (n = 13; 48%), nausea (n = 4; 15%), and vague abdominal pain (n = 5; 19%). There was one case of radiation-induced gastritis from inadvertent deposition of microspheres to the gastrointestinal tract (n = 1; 4%). Three patients (11%) experienced ascites/pleural effusion after treatment with TheraSphere as a consequence of liver failure in advanced-stage metastatic disease. With the exception of these three patients whose sequelae were not considered to be related to treatment, all observed toxicities were transient and resolved without medical intervention.

CONCLUSION

TheraSphere administration appears to provide stabilization of liver disease with minimal toxicity in patients in whom standard systemic chemotherapy regimens have failed.

A phase I dose-finding clinical pharmacokinetic study of an oral formulation of irinotecan (CPT-11) administered for 5 days every 3 weeks in patients with advanced solid tumours

BACKGROUND

Oral administration of irinotecan (CPT-11) should allow sustained exposure to the drug without the inconvenience of intravenous delivery and with fewer side-effects.

PATIENTS AND METHODS

The present phase I trial of CPT-11, administered orally as a powder-filled capsule for 5 consecutive days every 3 weeks at doses ranging from 30 to 90 mg/m(2)/day, was conducted in 47 patients for whom a satisfactory standard treatment option was no longer available (24 males/23 females; median age 51 years, range 26-85). Tumour types included melanoma (11), colorectal (4), urinary tract (3), lung/pleura (4), thyroid (3), liver (3), gallbladder (2), cervix/uterus (3), breast (2), pancreas (2), carcinoma and other cancer types (10).

RESULTS

A total of 171 cycles were administered (median 3, range 1-11). Dose limiting toxicities (DLTs) occurred during the first cycle in five of 31 patients in the dose-escalation part of the study: one patient at the 50 mg/m(2)/day dose level (diarrhoea grade 4); one patient at the 80 mg/m(2)/day dose level (prolonged neutropenia grade 4 and diarrhoea grade 3); and three patients at the 90 mg/m(2)/day dose level (diarrhoea, vomiting and neutropenia). The 80 mg/m(2)/day dose level was expanded, as a feasibility study, to include 16 additional patients, five of whom had received extensive prior pelvic irradiation. A further three patients in this cohort experienced DLTs, two of whom had received extensive prior pelvic irradiation. One patient died on study day 15 during the first cycle of oral CPT-11 following grade 3 diarrhoea, febrile neutropenia and a necrotic enterocolitis. Overall the grade 3/4 toxicities in 47 patients were asthenia (19%), anorexia (17%), neutropenia (14.9 %), diarrhoea (13%), nausea (12.7%), vomiting (8.5%) and thrombocytopenia (8.5%). Partial responses were observed in two melanoma patients and disease stabilisation was noted in 17 (36.1%) patients. Pharmacokinetic parameters were recorded for 46 patients.

CONCLUSIONS

At the maximum tolerated dose, defined as 80 mg/m(2)/day for 5 days every 3 weeks, oral CPT-11 was shown to be well tolerated and safe with few of the haematological toxicities associated with the intravenous formulation.

Phase II Trial of Gemcitabine Plus Irinotecan In Patients With Esophageal Cancer

OBJECTIVES

Metastatic esophageal carcinoma is an incurable disease with median survival duration of 6 to 8 months. Based on preclinical data suggesting a dose-dependent synergy between gemcitabine and irinotecan we have conducted a phase II trial in patients with advanced or metastatic esophageal carcinoma.

METHODS

Patient eligibility included a diagnosis of squamous cell or adenocarcinoma of the esophagus/gastroesophageal (GE) junction, metastatic or recurrent disease, no CNS metastasis, no prior chemotherapy, prior adjuvant/neoadjuvant chemotherapy was allowed, no prior gemcitabine or irinotecan, performance status of 0 to 2 and adequate organ function. Patients received gemcitabine 1000 mg/m2 and irinotecan 100 mg/m2 given day 1 and day 8, every 3 weeks. The primary end point was the 6-month survival rate. The secondary end point was to assess qualitative and quantitative toxicities.

RESULTS

Fifty-seven eligible patients were accrued. There were 4 treatment-related deaths. The primary grade 3 to 4 toxic events were diarrhea, dehydration, neutropenia, thrombocytopenia, anemia, and anorexia; and 4 episodes of grade 3 to 5 febrile neutropenia, 1 fatal. The study was designed to detect a difference between the null hypothesis of 30% 6-month survival and the alternative hypothesis of 50% 6-month survival. The Kaplan-Meier estimate of 6-month survival is 56% (95% CI: 43-69%), with a median of 6.3 months. The median time to progression was 3.7 months. The 6-month progression-free survival estimate is 25% (95% CI: 13-36%).

CONCLUSIONS

The length of survival suggests that this combination has benefit similar to platinum containing regimens, however, the toxicity is substantial and is unlikely to prove superior to platinum containing regimens.

Irinotecan for children with relapsed solid tumors

Irinotecan is expected to become a new drug for childhood solid tumors. Sixteen children with relapsed solid tumors received irinotecan 180 mg/m2/day for 3 consecutive days, repeated once after 25 days off. Their original tumors were neuroblastoma in 7, rhabdomyosarcoma in 3, nephroblastoma and undifferentiated sarcoma in 2 each, and primitive neuroectodermal tumor and leiomyosarcoma in 1 each. The average age at trials was 6 years. Partial response was achieved in 5 (31.3%) (neuro-blastoma, rhabdomyosarcoma, nephroblastoma, undifferentiated sarcoma, and leiomyosarcoma), and decrease in tumor marker in the other 2. Irinotecan appears promising, and could become included in the first-line treatment.

Prognostic factors after potentially curative resection in stage II or III colon cancer

It is important to identify factors that are predictive of outcome after a curative resection in colon cancer in order to optimize adjuvant therapy. To investigate these prognostic factors we conducted a retrospective analysis of our clinicopathological data. A total of 190 patients with a pathological stage II or III colon cancer underwent potentially curative resection with lymphadenectomy at our hospital between 1990 and 1998. These patients received no preoperative chemotherapy, immunotherapy or radiotherapy. Postoperative adjuvant chemotherapy using oral fluoropyrimidines was performed in 127 patients, and the other 63 patients underwent surgery alone. Univariate and multivariate analyses for prognostic factors were carried out. The univariate analysis revealed that invasion to adjacent organs, N1-2, positive mesenteric lymph node metastasis (MLN+), lymphatic permeation (ly)1-3, venous invasion (v)1-3, and v2-3 were each significant factors indicating worse disease-free survival, and that N1-2, MLN+, ly1-3, v1-3 and v2-3 were each significant factors for worse overall survival. In the multivariate analysis, MLN+ and vl-3 were significant factors for worse disease-free survival, and for worse overall survival. In conclusion, stage II or III colon cancer patients positive for mesenteric lymph node metastasis or for venous invasion have a greater risk of recurrence and death after potentially curative resection. Postoperative adjuvant chemotherapy using oral fluoropyrimidines did not significantly reduce the risk of recurrence and death in these patients. More effective adjuvant chemotherapy than oral fluoropyrimidine should be considered, especially in such high-risk patients.

Optimal antidiarrhea treatment for antitumor agent irinotecan hydrochloride (CPT-11)-induced delayed diarrhea

PURPOSE

An antitumor camptothecin derivative CPT-11 has proven a broad spectrum of solid tumor malignancy, but its severe diarrhea has often limited its more widespread use. We have demonstrated from a rat model that intestinal beta-glucuronidase may play a key role in the development of CPT-11-induced delayed diarrhea by the deconjugation of the luminal SN-38 glucuronide, and the elimination of the intestinal microflora by antibiotics or dosing of TJ-14, a Kampo medicine that contains beta-glucuronidase inhibitor baicalin, exerted a protective effect. In the present study, we assessed the efficacy of several potential treatments in our rat model to clarify which is the most promising treatment for CPT-11-induced delayed diarrhea.

METHODS AND RESULTS

Oral dosing (twice daily from days -1 to 4) of streptomycin 20 mg/kg and penicillin 10 mg/kg (Str/Pen), neomycin 20 mg/kg and bacitracin 10 mg/kg (Neo/Bac), both of which inhibited almost completely the fecal beta-glucuronidase activity, or TJ-14 1,000 mg/kg improved the decrease in body weight and the delayed diarrhea symptoms induced by CPT-11 (60 mg/kg i.v. from days 1 to 4) to a similar extent. The efficacy was less but significant in activated charcoal (1,000 mg/kg p.o. twice daily from days -1 to 4). In a separate experiment using rats bearing breast cancer (Walker 256-TC), TJ-14, Neo/Bac, and charcoal at the same dose regimen improved CPT-11-induced intestinal toxicity without reducing CPT-11's antitumor activity. In contrast, oral dosing (twice a day) of cyclosporin A (50 mg/kg), a P-glycoprotein and cMOAT/MRP2 inhibitor or valproic acid (200 mg/kg), a UDP-glucuronosyltranferase inhibitor, exacerbated the intestinal toxicity without modifying CPT-11's antitumor activity.

CONCLUSIONS

The result clearly demonstrated the ability of Neo/Bac, Str/Pen, and TJ-14, less but significant ability of activated charcoal, to ameliorate CPT-11-induced delayed-onset diarrhea, suggesting the treatments decreasing the exposure of the intestines to the luminal SN-38 are valuable for improvement of CPT-11-induced intestinal toxicity. In contrast, the treatments affecting the biliary excretion of CPT-11 and its metabolites might have undesirable results.

Single-agent irinotecan for recurrent/metastatic colorectal cancer: a retrospective analysis

OBJECTIVE

To evaluate the efficacy, toxicity and factors affecting the survival rate of patients treated with irinotecan.

SUBJECTS AND METHODS

Data from the medical records of 74 patients who had recurrent/metastatic colorectal cancer treated with single-agent irinotecan were analyzed.

RESULTS

The mean age for all the patients was 56 years (range 19-77). Forty-one (55%) and 33 (45%) patients had recurrent and/or metastatic colon cancer, respectively. All the patients were treated with irinotecan 350 mg/m(2) every 21 days. Grade 3-4 emesis, grade 3-4 diarrhea, grade 3-4 neutropenia and severe early cholinergic events developed in 7, 15, 7 and 1.3% of patients, respectively. One patient died due to acute renal failure. The overall response rate was 14% (complete response 5%, partial response 9%); 61% had stable response while another 25% had progressive disease. Patients with multiple metastatic foci, patients < or =50 years of age and patients with peritonitis carcinomatosa were shown to have worse outcomes than others. The median duration of response was 16.7 months. The median progression-free survival and overall survival were 4 and 14 months, respectively.

CONCLUSION

The data show that irinotecan was useful in the treatment of recurrent/metastatic colorectal cancer with acceptable toxicity.

Novel Single Nucleotide Polymorphism of UGT1A7 Gene in Japanese

We sequenced exon 1 of the UDP-glucuronosyltransferase (UGT) 1A7 gene from 52 Japanese cancer patients. Four single nucleotide polymorphisms (SNPs) were found. Three of them caused UGT1A7*2 and UGT1A7*3. A novel SNP (98973G>C) causing amino acid substitution (Ser141Cys) was found. The sequence is as follows: SNP, 050824FujitaK002; Gene Name, UGT1A7; Accession Number, AF297093; Length, 25 bases; 5'-TAAAGGAGAGTTG/CTTTTGATGCAGT-3'. One out of 52 cancer patients was heterozygous for the variant allele, resulting in the allele frequency of 0.96%. The patient did not possess UGT1A7*2 or UGT1A7*3.

A Multicenter Phase II Study of “Adjuvant” Irinotecan Following Resection of Colorectal Hepatic Metastases

OBJECTIVES

This study evaluates the efficacy and toxicity of single-agent irinotecan following hepatectomy for metachronous colorectal metastases, and examines the predictive value of p27 and p53 expression and of microsatellite instability (MSI) status.

METHODS

Twenty-nine patients, previously treated with 5-fluorouracil, with operable hepatic colorectal metastases underwent hepatectomy and received adjuvant irinotecan (thrice weekly) for 6 planned cycles. Metastases were examined for p53 and p27 expression by immunohistochemistry and for MSI using mono- and dinucleotide markers.

RESULTS

The starting dose of irinotecan was 350 mg/m2 (in 3 patients), 300 mg/m2 (n = 14), and 250 mg/m2 (n = 12). Four patients failed to complete 6 cycles (2 progressive disease and 2 toxicity). Grade > or =3 toxicity was experienced in 8% of cycles (13 of 165). The estimated median relapse-free survival (RFS) was 45.2 months. RFS at 18 months was estimated to be 59% (95% confidence interval [CI], 43-80), 2-year overall survival (OS) was 85% (95% CI, 72-99.8), and the median follow-up was 27.9 months. Six patients (21%) have died; median OS has not been reached. In univariate analyses, p27 and MSI status were not predictive for RFS while p53 approached statistical significance (P = 0.051). Duration of chemotherapy was the only significant predictive factor (P = 0.006).

CONCLUSION

The tolerability of this regimen after major liver resection supports further evaluation of irinotecan-based adjuvant chemotherapy in this group of patients.

Irinotecan plus cisplatin combination against metastatic gastric cancer: phase II study

In this phase II study, we aimed to detect efficacy and toxicity of the combination of CPT-11 and cisplatin administered to patients with metastatic gastric carcinoma. On d 1, CPT-11, 100 mg/m2, was administered by intravenous infusion for 90 min, followed by a 2 h infusion of cisplatin, at 70 mg/m2 every 3 wk. Forty-one patients were enrolled into the study. Twenty-eight patients were chemotherapy naive. The total number of chemotherapy cycles administered was 165, and the median number of cycles received was 4 (range, 1-8 cycles). The median follow-up time was 12 mo (range, 4-34 mo). There were 4 complete responses (9.7%) and 14 partial responses (34.2%), which result in a response rate of 43.9% (18 of 41 patients). The median time to progression was 8.0 +/- 0.8 mo with 56% and 13% of patients progression free at 6 and 12 mo, respectively. The median overall survival was 9.0 +/- 1.1 mo, with 68 % and 32% of patients alive at 6 and 12 mo, respectively. Grade 3-4 nausea and vomiting was observed in five patients (12%) and grade 3-4 neutropenia in five patients (12%). Grade 3 infection was observed in only one patient (2%). Grade 2 transient liver dysfunction related to chemotherapy was observed in one patient (2%). Chemotherapy was stopped due to nephrotoxicity in one patient (2%). There was no treatment-related death. In conclusion, administration of CPT-11 and cisplatin in this particular dose every 3 wk is effective and well-tolerated treatment regimen.

Phase I/II Dose-Escalation Study of Pemetrexed plus Irinotecan in Patients with Advanced Colorectal Cancer

BACKGROUND

Pemetrexed and irinotecan have demonstrated antitumor activity as single agents in lung, pancreatic, breast, and colorectal cancer (CRC). The distinct mechanisms of action and patterns of resistance displayed by pemetrexed and irinotecan make them attractive agents for combination therapy.

PATIENTS AND METHODS

This phase I/II, nonrandomized, open-labeled, single-arm study was composed of 3 segments. The initial phase II portion of the study enrolled 23 patients with advanced CRC who had received 1 previous dose of 5-fluorouracil (5-FU)-based chemotherapy for advanced disease. Because of poorer than anticipated efficacy, a phase I dose-escalation study using vitamin supplementation (n = 12) was added to the original protocol. The phase II dose-escalation portion of the study enrolled 36 patients (64% with previous oxaliplatin-based therapy) who received pemetrexed 500 mg/m2 followed by irinotecan 300 mg/m2 on day 1, every 21 days.

RESULTS

For the 35 evaluable patients in the phase II dose-escalation study, the objective response rate was 11.4% (95% confidence interval, 3.2%-26.7%); there was 1 patient with a complete response, 3 with partial responses, and 17 with stable disease. Three of four responders had received previous oxaliplatin-based combination therapy. Grade 3/4 hematologic toxicities included leukopenia (5.6%), anemia (2.8%), and thrombocytopenia (2.8%). Grade 3/4 nonhematologic toxicities included diarrhea (11.1%), increased aminotransferase levels (8.3%), nausea (8.3%), febrile neutropenia (5.6%), vomiting (5.6%), and reduced creatinine clearance (2.8%).

CONCLUSION

Pemetrexed plus irinotecan appears to be at least as active as FOLFIRI (leucovorin/5-FU/irinotecan) for second-line therapy of CRC following 5-FU-based combination chemotherapy. Further studies are warranted.

In vitro and in vivo irinotecan-induced changes in expression profiles of cell cycle and apoptosis-associated genes in acute myeloid leukemia cells

OBJECTIVE

To study irinotecan (CPT-11)-induced changes in expression profiles of genes associated with cell cycle control and apoptosis in myeloid leukemia cells in vitro and in vivo.

METHODS

HL60 cells were exposed to clinically achievable concentrations of 7-ethyl-10-hydroxycamptothecin (SN-38), the active metabolite of CPT-11, and blood sampled from patients with acute myeloid leukemia and chronic myeloid leukemia in myeloid blast transformation treated with CPT-11. Gene expression changes were studied by cDNA microarray and correlated with biological responses by studying DNA distributions by flow cytometry.

RESULTS

cDNA microarray analysis showed down-regulation and up-regulation of specific cell cycle-associated genes, consistent with loss of S-phase cells and temporary delay of G(1)-S-phase transition seen by flow cytometry. Flow cytometry showed that cells in S phase during SN-38 exposure underwent apoptosis, whereas cells in G(2)-M and G(1) were delayed in G(1) and entered S phase only 6 to 8 hours after drug removal, consistent with the observed changes in gene expression. Proapoptotic changes in gene transcription included down-regulation of antiapoptotic genes and up-regulation of proapoptotic genes. Many gene expression changes observed following in vitro SN-38 exposure were also seen following in vivo administration of 10 or 15 mg/m(2) CPT-11; notably, proapoptotic changes included reduced transcription of survivin pathway-associated genes and increased transcription of death receptor 5.

CONCLUSION

CPT-11-induced changes in gene expression profiles in vitro and in vivo are consistent with temporary delay in G(1)-S transition and enhanced responsiveness to apoptosis, both of which may contribute to the synergistic interactions of this drug with antimetabolites.

The MMP-9 expression determined the efficacy of postoperative adjuvant chemotherapy using oral fluoropyrimidines in stage II or III colorectal cancer

BACKGROUND

The aim of this study was to determine any correlation between the efficacy of postoperative adjuvant chemotherapy using oral fluoropyrimidines and the matrix metalloproteinase 9 (MMP-9) expression in primary colorectal cancer tissues.

PATIENTS AND METHODS

The data on 307 patients with colorectal cancer at stage II or III, who underwent potentially curative resection with lymphadenectomy, were reviewed. Of these, 188 received postoperative administration of oral fluoropyrimidines such as UFT and 5'-DFUR (chemotherapy group), while the other 119 patients underwent surgery alone (surgery-alone group). Immunostaining for MMP-9 was performed using surgical specimens of all 307 primary tumors and 18 recurrent tumors.

RESULTS

Overall, MMP-9 was positively expressed in the primary tumor in 44% of patients. Multivariate analysis revealed that the MMP-9 expression was a worse prognostic factor with a second highest hazard ratio for recurrence. The disease-free survival rate in the chemotherapy group was significantly higher than that in the surgery-alone group. However, no significant difference in disease-free survival rate between the two groups was found in patients with a tumor positive for MMP-9. There was a strong positive correlation of MMP-9 expression between the primary tumors and the recurrent liver or lung tumors.

CONCLUSIONS

The efficacy of postoperative adjuvant chemotherapy using oral fluoropyrimidines such as UFT and 5'-DFUR may not be as great for patients with a tumor positive for MMP-9 having a greater risk to postoperative recurrence.

Pharmacokinetic Changes of Irinotecan by Intestinal Alkalinization in an Advanced Colorectal Cancer Patient

The prevention of irinotecan (CPT-11)-induced diarrhea, a well-known adverse reaction to the drug, by treatment with intestinal alkalinization has been carried out in patients with colorectal cancer in Japan. Under acidic conditions, CPT-11 and its active metabolite, SN-38, exists preferably as the lactone form, whereas both exist as the carboxylate form under basic conditions. It has been suggested that the lactone forms of both CPT-11 and SN-38 are diffused passively across the intestinal mucosal membranes, whereas the carboxylate forms are actively transported. The intestinal uptake rate of both forms appears to be pH sensitive under physiological conditions, but it remains unclear whether intestinal alkalinization treatment affects the pharmacokinetics of CPT-11 and SN-38. This study was designed to evaluate the pharmacokinetics of CPT-11 and SN-38 in a colorectal cancer patient with or without alkalinization treatment. We found that intestinal alkalinization significantly decreased the plasma levels of CPT-11 and SN-38. In particular, the AUC of SN-38 was markedly decreased to 56 from 107 ng.h/mL. Intestinal alkalinization was effective in preventing CPT-11-induced diarrhea, but this treatment changed the pharmacokinetics of CPT-11 and SN-38 in the body.