ESSAI DE PHASE III RANDOMISE EVALUANT LE FOLFOX AVEC OU SANS DOCETAXEL (TFOX) EN 1ère LIGNE DE CHIMIOTHERAPIE DES ADENOCARCINOMES OESO-GASTRIQUES LOCALEMENT AVANCES OU METASTATIQUES

Gastric cancer is the fourth commonest cancer and the second largest cause of mortality from cancer. Surgical resection of localised forms of gastric cancer offers the only chance of a cure. The vast majority of patients, however, present with advanced disease from the outset (locally advanced or metastatic) or recurrent after resection of a localised form.

For metastatic or locally advanced stages of gastric or gastro-oesophageal junction adenocarcinoma, the combination of 2 chemotherapy drugs (dual therapy) as compared with monotherapy or no chemotherapy, makes it possible to improve the tumour response and patient survival. Dual therapy comprising cisplatin + fluoropyrimidine (CF protocol) is considered as one of the first-line chemotherapy treatment standards.

The addition of docetaxel to the CF regime (referred to as the DCF protocol) has made it possible to improve the tumour response rate, the time to tumour progression and overall survival in a randomised phase III trial. This improvement in treatment efficacy was achieved, however, at the expense of a significant increase in grade 3-4 toxicity, including diarrhoea , neutropenia, and neutropenia with complications. Although DCF is considered as a therapeutic standard for advanced forms of gastric cancer, its use is limited in clinical practice due to its high toxicity.

Oxaliplatin has shown its usefulness in treatment of oesophagogastric cancer, with an efficacy at least equal to that of cisplatin. Peripheral sensory neuropathy was less common in the 5FU-cisplatin arm. In terms of treatment efficacy, 5FU-oxaliplatin versus 5FU-cisplatin was associated with a non-significant improvement in median progression free survival rates, and overall survival.

All these data thus suggest that 5FU-oxaliplatin is at least as efficacious and is better tolerated than 5FU-cisplatin, and also that docetaxel-5FU-cisplatin is more efficacious than 5FU-cisplatin, with limited use due to its high toxicity. In the logical continuation of development of chemotherapy protocols for metastatic gastric cancer, the question therefore arises of the usefulness of adding docetaxel to 5FU-oxaliplatin, in terms of efficacy and also tolerance.

In France, chemotherapy with FOLFOX is used extensively as a first line of treatment in advanced gastric cancer, but with progression-free survival and median survival rates that are still too low, and a poor response rate. The use of docetaxel at a dose of 50 mg/m2 every 2 weeks in combination with FOLFOX (TFOX protocol) has shown very interesting results in phase II studies in terms of efficacy and tolerability, and these are worth confirming through a phase III randomised trial. In fact, if these results are confirmed in phase III, TFOX could become the new first-line therapeutic standard for advanced gastric cancer, while limiting toxicity and preserving patients' quality of life, and could become the reference treatment to accompany the targeted therapies currently being developed for this disease.

The primary objective of this randomised phase III trial is to compare the progression-free survival on dual therapy with 5FU-oxaliplatin (FOLFOX protocol) with triple therapy with 5FU-oxaliplatin-docetaxel (TFOX protocol) in treatment of advanced forms of gastric or oesophagogastric junction adenocarcinoma. The secondary objectives are overall survival, the tumour response rate, toxicity, quality of life and the therapeutic index, defined as the ratio between the median progression-free survival and the febrile neutropenia rate.