Tamoxifen Citrate in Treating Patients With Metastatic or Recurrent Breast Cancer

DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the breast

  • Stage III (locally advanced), metastatic, or recurrent disease
  • Deemed not resectable

• Estrogen-receptor and/or progesterone-receptor positive disease

  • Receptor status is based on most recent results
  • Receptor testing on metastatic disease is not required
• Measurable or non-measurable disease

• History of CNS metastasis allowed provided it has been treated (surgery, radiotherapy, or radiosurgery) within the past 4 weeks and does not require medications to control symptoms

  • No known leptomeningeal disease allowed

PATIENT CHARACTERISTICS:

• ECOG performance status 0-2
• Menopausal status not specified
• Total bilirubin ≤ 1.5 times upper limit of normal (ULN)
• ALT and AST ≤ 2.5 times ULN (≤ 5 times ULN if liver metastases present)
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective nonhormonal contraception
• No medical or psychiatric conditions that would interfere with protocol compliance, the ability to provide informed consent, assessment of response, or anticipated toxicities
• More than 5 years since prior invasive malignancies except curatively treated basal cell or squamous cell carcinoma of the skin or carcinoma in situ of the cervix

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics

• No prior investigational agents in the metastatic setting

  • Other prior investigational agents in any setting must have been completed at least 6 weeks prior to study registration and should be discussed with the study PI

• Prior tamoxifen as adjuvant treatment is allowed as long as the patient did not have disease relapse or progression while on adjuvant tamoxifen or within 4 weeks of last dose

  • Prior tamoxifen for advanced disease is not allowed

• No prior chemotherapy or trastuzumab (Herceptin) for metastatic disease

  • Prior chemotherapy, trastuzumab, or bevacizumab in the adjuvant setting allowed provided it has been completed ≥ 4 weeks before study therapy

• Patients must not have had more than 2 lines of non-hormonal treatment in the locally advanced or metastatic setting, including trastuzumab (Herceptin), bevacizumab, or other biologics

  • Treatment in the advanced setting must have been completed at least 2 weeks prior to study initiation
• Prior aromatase inhibitors (e.g., anastrozole, letrozole, exemestane, aminoglutethamide) are allowed in the adjuvant or metastatic setting

• At least 2 weeks since prior and no concurrent medications that are strong to moderate inhibitors of CYP2D6 and may alter tamoxifen citrate metabolism including, but not limited to, any of the following:

  • Paroxetine (Paxil)
  • Fluoxetine (Prozac)
  • Bupropion (Wellbutrin)
  • Quinidine (Cardioquin)

• Patients may not initiate bisphosphonate therapy while receiving treatment on this study

  • Patients who have begun receiving bisphosphonate therapy prior to registration may continue at the same intervals used prior to study registration

• Concurrent radiotherapy to painful sites of bone disease or areas of impending fractures allowed provided the following criteria are met:

  • Radiotherapy was initiated before study entry
  • Sites of measurable or non-measurable disease are outside the radiotherapy port
  • Recovered from prior radiotherapy
• No other concurrent hormonal therapy
• No concurrent chemotherapy