Appendix D. Southwest Oncology Group (SWOG) criteria for assessing tumour response

Appendix D. Southwest Oncology Group (SWOG) criteria for assessing tumour response

SWOG criteria

Definition

Complete response (CR)

Complete disappearance of all measurable and evaluable disease. No new lesions. No disease-related symptoms. No evidence of non-evaluable disease, including normalisation of markers and other relevant abnormal lab values. All measurable, evaluable and non-evaluable lesions and sites must be assessed using the same technique as baseline.

Partial response (PR)

Greater than or equal to 50% decrease under baseline in the sum of products of perpendicular diameters of all measurable lesions. No progression of evaluable disease. No new lesions. All measurable and evaluable lesions and sites must be assessed using the same techniques as baseline.

Stable disease (SD)

Does not qualify for CR, PR, progression or unknown. All measurable and evaluable sites must be assessed using the same technique used at baseline.

Progressive disease (PD)

50% increase or an increase of 10 cm² (whichever is smaller) in the sum of products of all measurable lesions over smallest sum observed (over baseline if no decrease) using the same techniques as baseline, or clear worsening from previous assessment of any evaluable disease, or reappearance of any lesion which had disappeared, or appearance of any new lesion/site, or failure to return for evaluation due to death or deteriorating condition (unless clearly unrelated to this cancer). For 'scan-only' bone disease, increased uptake does not constitute clear worsening. Worsening of existing non-evaluable disease does not constitute progression.

Exceptions: (1) In cases for which initial tumour flare reaction is possible (hypercalcaemia, increased bone pain, erythema of skin lesions), either symptoms must persist beyond 4 weeks or there must be additional evidence of progression. (2) Lesions that appear to increase in size due to presence of necrotic tissue will not be considered to have progressed.

Unknown

Progression has not been documented and one or more measurable or evaluable sites have not been assessed.