PRINCIPLES OF MONITORING METASTATIC DISEASEMonitoring of patient symptoms and cancer burden during treatment of metastatic breast cancer is
PRINCIPLES OF MONITORING METASTATIC DISEASE
Monitoring of patient symptoms and cancer burden during treatment of metastatic breast cancer is important to determine whether the treatment is providing benefit and that the patient does not have toxicity from an ineffective therapy.
Components of Monitoring:
Monitoring includes periodic assessment of varied combinations of symptoms, physical examination, routine laboratory tests, imaging studies, and blood biomarkers where appropriate.
Results of monitoring are classified as response/continued response to treatment, stable disease, uncertainty regarding disease status, or progression of disease.
The clinician typically must assess and balance multiple different forms of information to make a determination regarding whether disease is being controlled and the toxicity of treatment is acceptable.
Sometimes, this information may be contradictory.
Definition of Disease Progression:
Unequivocal evidence of progression of disease by one or more of these factors is required to establish progression of disease, either because of ineffective therapy or acquired resistance of disease to an applied therapy.
Progression of disease may be identified through evidence of growth or worsening of disease at previously known sites of disease and/or of the occurrence of new sites of metastatic disease.
●Findings concerning for progression of disease include:
▲Worsening symptoms such as pain or dyspnea
▲Evidence of worsening or new disease on physical examination
▲Declining performance status
▲Unexplained weight loss
▲Increasing alkaline phosphatase, ALT, AST, or bilirubin
▲New radiographic abnormality or increase in the size of pre-existing radiographic abnormality
▲New areas of abnormality on functional imaging (eg, bone scan, PET/CT scan)
▲Increasing tumor markers (eg, CEA, CA15-3, CA27.29)
Rising tumor markers (eg, CEA, CA15-3, CA27.29) are concerning for tumor progression, but may also be seen in the setting of responding disease.
An isolated increase in tumor markers should rarely be used to declare progression of disease.
Changes in bone lesions are often difficult to assess on plain or cross-sectional radiology or on bone scan.
For these reasons, patient symptoms and serum tumor markers may be more helpful in patients with bone-dominant metastatic disease.
Use of Objective Criteria for Response/Stability/Progression:
●The most accurate assessments of disease activity typically occur when previously abnormal studies are repeated on a serial and regular basis.
Generally, the same method of assessment should be used over time (eg, an abnormality found on chest CT scan should generally be monitored with repeat chest CT scans).
●Some non-clinically important variation in measurement of abnormalities by all serial studies is common and expected. Therefore, the use of objective and widely accepted criteria for response, stability, and progression of disease are encouraged.
Such systems include the Response Evaluation Criteria In Solid Tumors (RECIST) guidelines (Eisenhauer EA, Therasse P, Bogaerts J, et al. New response evaluation criteria in solid tumours: revised RECIST guideline (version 1.1). Eur J Cancer 2009;45:228-247) and the WHO criteria (Miller AB, Hoogstraten B, Staquet M, and Winkler A. Reporting results of cancer treatment. Cancer 1981;47:207-214).
●Studies of functional imaging, such as radionuclide bone scans and PET imaging, are particularly challenging when used to assess response. In the case of bone scans, responding disease may result in a flare or increased activity on the scan that may be misinterpreted as disease progression, especially on the first follow-up bone scan after initiating a new therapy. PET imaging is challenging because of the absence of a reproducible, validated, and widely accepted set of standards for disease activity assessment.
Frequency of Monitoring:
The optimal frequency of repeat testing is uncertain, and is primarily based upon the monitoring strategies utilized in breast cancer clinical trials. The frequency of monitoring must balance the need to detect progressive disease, avoid unnecessary toxicity of any ineffective therapy, resource utilization, and determine cost. The following table is to provide guidance, and should be Modified for the individual patient based upon sites of disease, biology of disease, and length of time on treatment. Reassessment of disease activity should be performed in patients with new or worsening signs or symptoms of disease, regardless of the time interval from previous studies.
Eisenhauer EA, Therasse P, Bogaerts J, 等。新的实体瘤疗效反应评价标准：修订的RECIST指南(1.1版)。Eur J Cancer 2009;45:228-247) 以及 WHO标准(Miller AB, Hoogstraten B, Staquet M, and Winkler A. 癌症治疗结果记录。 Cancer 1981;47:207-214.