Continuing vs Intermittent Trabectedin in Patients With Advanced Soft Tissue Sarcoma

Inclusion Criteria (for the selection part):

* Inoperable or metastatic soft tissue sarcoma and/or uterine sarcoma
* Measurable lesions (RECIST 1.1)
* Performance status ≤ 2
* Age ≥ 18
* Normal hematological parameters (polynuclear neutrophils ≥ 1500, hemoglobin level ≥ 9 g/dl, platelets counts ≥ 100,000)
* Adequate biological parameters :
* Adequate hepatic function (bilirubin ≤ ULN , SGPT/ALT and SGOT/AST ≤ 2.5 x ULN)
* Alkaline phosphatases ≤ 2.5 x ULN, If Alkaline phosphatases ≥ 2.5 ULN, hepatic isoenzymes 5-nucleotidases or GGT tests must be performed; hepatic isoenzymes 5- nucleotidases and/or GGT must be within the normal range
* Albumin ≥ 25 g/L
* Adequate renal function : Serum creatinine ≤ 1.5 x ULN
* Creatine phosphokinase ≤ 2.5 x ULN
* Adequate central venous access
* Pregnant or lactating women or men of reproductive potential must use effective contraceptive methods
* Patient covered by government health insurance
* Information sheet given to the patient (Patient information sheet 1)

Exclusion Criteria (for the selection part):

* Patients that have received more than one regimen of chemotherapy for metastatic or inoperable soft tissue or uterine sarcoma, after the failure/intolerance of doxorubicin and ifosfamide. Maintenance treatment does not count as treatment line
* The following histological subtypes : GIST, rhabdomyosarcoma, aggressive fibromatosis, desmoïd tumour, PNET, carcinosarcoma, and all bone sarcomas
* Single tumour in an irradiated region
* Other malignant tumour over the past five years (except basal cell carcinoma or cervical carcinoma in situ adequately treated)
* Currently active bacterial or fungus infection (\> grade 2 CTC \[CTCAE\] Version 4.02). Known HIV1, HIV2, hepatitis B or hepatitis C infections
* Presence of known leptomeningeal or brain metastasis
* Patients unable to receive corticotherapy
* Any circumstance that could jeopardise compliance or proper follow-up during the trial
* Pregnant or nursing women

Inclusion Criteria (for the randomized part):

* Patient registered in the selection part
* Stable tumour or objective response (CR + PR) after 6 Trabectedin (Yondelis®) cycles, according to local assessment
* Available copies of thoraco-abdominal and pelvic scan performed prior to the first cycle and after the sixth cycle
* Performance status ≤ 2
* Patients receiving at least 1 mg/m²/3 weeks of Trabectedin at the time of the sixth cycle
* Normal hematological parameters (polynuclear neutrophils ≥ 1500, hemoglobin level ≥ 9 g/dl, platelets counts ≥ 100,000)
* Adequate biological parameters :
* Adequate hepatic function (bilirubin ≤ ULN , SGPT/ALT and SGOT/AST ≤ 2.5 x ULN)
* Alkaline phosphatases ≤ 2.5 x ULN, If Alkaline phosphatases ≥ 2.5 ULN, hepatic isoenzymes 5-nucleotidases or GGT tests must be performed; hepatic isoenzymes 5- nucleotidases and/or GGT must be within the normal range
* Albumin ≥ 25 g/L
* Adequate renal function : Serum creatinine ≤ 1.5 x ULN
* Creatine phosphokinase (CPK) ≤ 2.5 x ULN
* Adequate central venous access
* Pregnant or lactating women or men of reproductive potential must use effective contraceptive methods
* Informed consent form signed by the patient or the patient's legal representative (patient information sheet 2 and informed consent)

Exclusion Criteria (for the randomized part):

* Tumour progression (according to RECIST 1.1) during the first six Yondelis cycles
* Non-availability of baseline scans prior to the first cycle and following the sixth cycle
* Currently active bacterial or fungus infection (\> grade 2 CTC \[CTCAE\] Version 4.02). Known HIV1, HIV2, hepatitis B or hepatitis C infections
* Presence of known leptomeningeal or brain metastasis
* Creatinine clearance less than 30 ml/min
* Patients unable to receive corticotherapy
* Any circumstance that could jeopardise compliance or proper follow-up during the trial
* Pregnant or nursing women
* Hypersensitivity to Trabectedin or any excipient in prior cycles