A phase II trial of weekly fractionated irinotecan and cisplatin for advanced gastric cancer

The UGT1A9*22 genotype identifies a high-risk group for irinotecan toxicity among gastric cancer patients

Several studies have shown associations between irinotecan toxicity and UGT1A genetic variations in colorectal and lung cancer, but only limited data are available for gastric cancer patients. We evaluated the frequencies of UGT1A polymorphisms and their relationship with clinicopathologic parameters in 382 Korean gastric cancer patients. Polymorphisms of UGT1A1*6, UGT1A1*27, UGT1A1*28, UGT1A1*60, UGT1A7*2, UGT1A7*3, and UGT1A9*22 were genotyped by direct sequencing. In 98 patients treated with irinotecan-containing regimens, toxicity and response were compared according to the genotype. The UGT1A1*6 and UGT1A9*22 genotypes showed a higher prevalence in Korean gastric cancer patients, while the prevalence of the UG1A1*28 polymorphism was lower than in normal Koreans, as has been found in other studies of Asian populations. The incidence of severe diarrhea after irinotecan-containing treatment was more common in patients with the UGT1A1*6, UGT1A7*3 and UGT1A9*22 polymorphisms than in controls. The presence of the UGT1A1*6 allele also showed a significant association with grade III–IV neutropenia. Upon haplotype and diplotype analyses, almost every patient bearing the UGT1A1*6 or UGT1A7*3 variant also had the UGT1A9*22 polymorphism, and all severe manifestations of UGT1A polymorphism-associated toxicity were related to the UGT1A9*22 polymorphism. By genotyping UGT1A9*22 polymorphisms, we could identify high-risk gastric cancer patients receiving irinotecan-containing chemotherapy, who would experience severe toxicity. When treating high-risk patients with the UGT1A9*22 polymorphism, clinicians should closely monitor them for signs of toxicity such as severe diarrhea or neutropenia.

Phase II and UGT1A1 Polymorphism Study of Two Different Irinotecan Dosages Combined with Cisplatin as First-Line Therapy for Advanced Gastric Cancer

BACKGROUND

We investigated the efficacy and safety of biweekly irinotecan and cisplatin (IP) as first-line treatment in advanced gastric cancer patients.

METHODS

Irinotecan 125 mg/m2 on day 1 and cisplatin 60 mg/m2 on day 2 were administrated every 14 days. UGT1A1*28/*6 and toxicities were analyzed.

RESULTS

Forty-one eligible patients were enrolled. Fifteen patients, who were defined as the high-dose group, received starting doses of irinotecan 125 mg/m2. Twenty-six patients, who were defined as the low-dose group, received starting doses of irinotecan 80 mg/m2 and cisplatin 50 mg/m2. The response rate was 53.3% in the irinotecan high-dose group and 53.8% in the irinotecan low-dose group. The most common grade 3/4 toxicity was neutropenia (68.3%). No significant difference in grade 3/4 neutropenia was found between patients with the wild-type genotype and those with variant genotypes for UGT1A1*28 or UGT1A1*6.

CONCLUSIONS

The combination of biweekly irinotecan 80 mg/m2 and cisplatin 50 mg/m2 was active and tolerable. The role of the UGT1A1 genotype in clinical toxicity of an IP regimen requires further investigation.

A phase II study of a combined biweekly irinotecan and monthly cisplatin treatment for metastatic or recurrent gastric cancer

BACKGROUND

There is no universally confirmed standard chemotherapeutic regimen for advanced gastric cancer (AGC). The aim of this study was to investigate the efficacy and safety of combined biweekly irinotecan and monthly cisplatin treatments of patients with AGC. The primary end point was progression-free survival.

MATERIAL AND METHODS

AGC patients with or without measurable lesions received 70 mg/m2 irinotecan on days 1 and 15, and 80 mg/m2 cisplatin on day 1 every 4 weeks.

RESULTS

Of 40 enrolled patients, 21 patients had measurable disease. With a median follow-up duration of 35 weeks, the median progression-free survival and overall survival were 2.2 months and 8.0 months, respectively. The progression-free survival rate at 6 months was 30.0%. The most common adverse event of grade 3 to 4 was neutropenia (32.5%). Grade 3 diarrhea was observed in 2 patients (5.0%). There was no treatment-related death.

CONCLUSION

Current combined biweekly irinotecan and monthly cisplatin treatment did not show activity comparable with other active regimens in AGC.

Drug ratio-dependent antitumor activity of irinotecan and cisplatin combinations in vitro and in vivo

Irinotecan and cisplatin are two established anticancer drugs, which together constitute an effective combination for treating small-cell lung cancer. We investigated whether the efficacy of this combination could be improved by controlling drug ratios following in vivo administration. Irinotecan and cisplatin combinations were evaluated systematically for drug ratio-dependent synergy in vitro using a panel of 20 tumor cell lines. In vitro screening informatics on drug ratio-dependent cytotoxicity identified a consistently antagonistic region between irinotecan/cisplatin molar ratios of 1:2 to 4:1, which was bordered by two synergistic regions. Liposomal co-formulations of these two agents were developed that exhibited plasma drug half-lives of approximately 6 hours and maintained a fixed drug ratio for more than 24 hours. Drug ratio-dependent antitumor activity was shown in vivo for these liposome formulations, and irinotecan/cisplatin ratios between 5:1 and 10:1 were identified as therapeutically optimal. The relationship between irinotecan/cisplatin ratio and in vivo efficacy was consistent with in vitro drug ratio dependency results. Superior antitumor activity was observed for the liposome-encapsulated 7:1 molar ratio of irinotecan/cisplatin (designated CPX-571) compared with the free-drug cocktail in all models tested. Further efficacy studies in a range of human tumor xenografts, including an irinotecan-resistant model, showed that both liposomal agents contributed to the overall efficacy in a manner consistent with in vivo synergy. These results show the ability of drug delivery technology to enhance the therapeutic activity of irinotecan/cisplatin combination treatment by maintaining synergistic ratios in vivo. CPX-571, a fixed-ratio formulation of irinotecan and cisplatin, is a promising candidate for clinical development.

The new credo: induction chemotherapy in locally advanced gastric cancer: consequences for surgical strategies

Perioperative chemotherapy in stage II and stage III gastric cancer is now accepted as a standard of care in the Western world. Two randomized phase III studies have shown improved survival for patients with induction chemotherapy followed by surgery compared with surgery alone. It is generally accepted that patients who respond to induction therapy have a significantly improved survival compared with that in nonresponding patients. Unfortunately no prospectively tested markers predicting response and/or prognosis are available for clinical practice. In adenocarcinomas of the esophagogastric junction (AEG), fluorodeoxyglucose-positron emission tomography (FDG-PET) prospectively was established as a surrogate predicting response and prognosis. The MUNICON (Metabolic response evalUatioN for Individualisation of neoadjuvant Chemotherapy in oesOphageal and oesophagogastric adeNocarcinoma) I study confirmed prospectively the usefulness of early metabolic response evaluation and showed the feasibility of a PET-guided treatment algorithm. These findings are an important step forward in the tailoring of multimodal treatment in accordance with tumor biology. In gastric cancer, we have analyzed FDG-PET in a prospective study. In gastric cancer the issue is more complicated, because about 30% of gastric cancers cannot be visualized with sufficient contrast for quantification. Insufficient FDG uptake is mostly associated with diffuse-type gastric cancer with signet ring cells and mucinous content. In FDG-avid patients, FDG-PET can be used for response evaluation, comparable to that in AEG. The prognosis of FDG-nonavid patients is similar to that in metabolic nonresponders. The addition of new tracers such as fluorothymidine may increase the sensitivity of PET in the future. Treatment concepts such as immediate resection after only 2 weeks of induction therapy with or without adjuvant treatment could be considered in metabolic nonresponders, or modified chemotherapy regimens, possibly including biologically targeted drugs, could be considered in those with FDG-nonavid tumors.

Mitomycin C plus Infusional 5-Fluorouracil in Platinum-Refractory Gastric Adenocarcinoma: An Extended Multicenter Phase II Study

OBJECTIVE

To assess the toxicity and activity of bolus mitomycin C (MMC) in combination with a 24-hour continuous infusion of 5-fluorouracil (5-FU) in gastric cancer patients who had received at least one prior chemotherapy regimen.

PATIENTS AND METHODS

Patients were treated with MMC (10 mg/m(2)) on days 1 and 22, 5-FU (2.6 g/m(2)) as a 24-hour infusion, and folinic acid 500 mg/m(2) weekly for 6 weeks.

RESULTS

Thirty-four patients with gastric cancer, 16 after failure of first-line chemotherapy and 18 after failure of at least two prior chemotherapies, were included. In the intent-to-treat analysis, 9 (26.5%) of the 34 patients had a partial response and 10 (29.4%) a disease stabilization (disease control rate 56%). The median time to progression was 3.3 months (CI95: 2.8-3.7), and the median overall survival was 7.2 months (CI95: 5.9-8.4). Grade III/IV thrombocytopenia occurred in 14.7% of patients (n = 5), while the most frequent nonhematological grade III/IV toxicities were mucositis and diarrhea, each affecting 9% of patients.

CONCLUSIONS

As the tested regimen was generally safe and well tolerated by the patients, MMC plus infusional 5-FU/folinic acid may be a potential second-line regimen for patients with advanced gastric cancer.