Table 1 Inclusion and exclusion criteria for participation in the study

Inclusion

Postmenopausal women (no menstrual period for >12 months)

Histological proven adenocarcinoma of the breast treated primarily by modified radical or partial mastectomy and axillary dissection followed by radiotherapy of the residual breast

No more than four ipsilateral lymph nodes with metastases, not extending into the surrounding tissue and surgical margin free from disease

Tumor tissue positive for oestrogen receptor

Tamoxifen 20 mg/day commencing within 3 months of breast surgery and to continue for 5 years (provided by A. Dervos – G Dimitrakopoulos &Co OE)

Adequate bone marrow function (white blood cell count >4.0 × 10⁹/l, haemogoblin >100 g/l, platelet count >100 × 10⁹/l)

Adequate liver function (billirubin <60 μmol/l [that is, under three times the upper limit of normal)

Adequate renal function (creatinine <140 μmol/l)

Life expectancy >12 weeks

ECOG (Eastern Cooperative Oncology Group) status between 0 and 2 (In bed <50% of daytime)

Written informed consent by the patient.

Exclusion criteria

Known metastatic breast cancer

Radiotherapy, chemotherapy, immunotherapy, or investigation therapy within the preceding four weeks

Previous splenectomy or radiotherapy to spleen

Coexisting or previous other malignancies except in situ carcinoma of the cervix or basal cell carcinoma of the skin

Active uncontrolled infection

Psychiatric, addictive, or any disorder that compromises ability to give truly informed consent for participation in or to comply with the requirements of the study

Concurrent systematic corticosteroid treatment

Autoimmune disease (that is, rheumatoid arthritis, systematic lupus erythematosus; except autoimmune thyroiditis)