Letrozole in the Treatment of Advanced or Recurrent Hormone Receptor Positive Endometrial Cancer (deFEND)

Inclusion Criteria: Signed informed consent Age > 18 years Presence of histologically proven adenocarcinoma or adenosquamous carcinoma of the endometrium Presence of advanced or recurrent endometrial cancer, FIGO stage I-IV, incurable with surgery and/or radiation therapy Documented ER and/or PgR positive endometrial cancer. Hormone receptor positivity is defined according to routine practice at each participating laboratory. Patient must be postmenopausal defined as Age ≥55 years. Age <55 but no spontaneous menses for at least 1 year. Age <55 and spontaneous menses within the past 1 year, but currently amenorrheic (e.g., spontaneous or secondary to hysterectomy), and with postmenopausal gonadotrophin levels (luteinizing hormone and follicle stimulating hormone levels >40 IU/L) or postmenopausal estradiol levels (<5 ng/dL) or according to the definition of "postmenopausal range" for the laboratory involved. Bilateral oophorectomy Radiation menopause Presence of measurable disease (by clinical/radiological examination - according to RECIST criteria : minimum indicator lesion size : 20 mm (unless spiral CT scan in which case > 10 mm) ECOG performance status of 0, 1 or 2 Adequate bone marrow function (WBC ≥ 3.5 x 1'000'000'000/L and platelets ≥ 100.0 x 1'000'000'000/L) and hemoglobin > 10.0 g/dl Adequate renal function (creatinine < 120 µmol/L) and hepatic function (bilirubin < 25 µmol/L, AST (SGOT < 60 U/L) Minimum life expectancy of at least 6 months Patients who are accessible for treatment and follow-up Exclusion Criteria: Presence of non-measurable disease only Other concomitant anti-cancer treatment (except external radiation treatment [XRT] for symptomatic metastatic lesions if other assessable untreated lesions are present) Prior treatment with aromatase inhibitors or anti-estrogens (up to one previous progestational hormone therapy regimen for recurrent disease is permitted) Clear cell or papillary serous histology, uterine sarcomas, mixed Mullerian tumors (MMT) and/or adenosarcomas Other concurrent malignant disease with the exception of cone-biopsied in situ carcinoma of the cervix uteri, or adequately treated basal or squamous cell carcinoma of the skin, or other curable cancers e.g. Hodgkin's disease or non-Hodgkin lymphoma (NHL), provided 5 years have elapsed from completion of therapy, and there has been no recurrence Known central nervous system (CNS) metastases, bilateral diffuse lymphangiosis carcinoma of the lung (>50 % of lung involvement, or dyspnea at rest requiring supplemental oxygen therapy), evidence of metastases estimated as more than a third of the liver as defined by sonogram and/or CT scan Uncontrolled endocrine disorders such as diabetes mellitus, confirmed hypo- or hyperthyroidism, Cushing's Syndrome, Addison's disease (treated or untreated) Unstable angina and uncontrolled cardiac disease Treatment with other investigational drugs (drugs not marketed for any indication) within the past 30 days and/or the concomitant use of investigational drugs A history of non-compliance to medical regimens and patients who, in the opinion of the investigator, are unlikely to cooperate fully during the study Inability to swallow pills Additional protocol-defined inclusion/exclusion criteria may apply.