Survival effect of systemic therapy on patients developing metastatic breast carcinoma

Abstract

A multivariate analysis was performed to assess the effect of post-relapse systemic therapy on a series of patients with metastatic breast cancer who at initial presentation had no detectable metastases (M_∘), were ≤ 70 years of age, presented with unilateral localized disease and no other associated malignancy, and were treated between 1965 and 1984 with successive protocols for primary disease and subsequently developed distant metastasis. All 760 patients analyzed relapsed with at least one metastasis, and were studied retrospectively with no selection criteria according to any specific protocol. All had recorded clinical data on menopause, stage, clinical tumor aggressiveness (PEV), initial chemo or hormonal therapy, and time to relapse, and had ongoing follow up at our Center, with salvage chemotherapy and/or hormonal therapy having been given to some but not all patients.

A brief metastasis-free survival (p < 0.000001), and factors associated with electing pre-relapse chemotherapy (p < 0.000001) were associated with shortened post-relapse survival, while post-relapse therapy (chemo p < 0.0001, and hormonal p < 0.00001, replacing chemotherapy in the model) apparently increased post-relapse survival in the group overall. This result was similar in the inoperable patient group [with inflammatory breast carcinoma an additional risk factor (p < 0.0005)], as well as the operable group. However, in the operable group, when the pathologic criteria of histologic grade and nodal status were introduced into the analysis, post-relapse therapy was not seen to be an important factor for survival in any subgroup. Histograde (p < 0.000001), nodal status (p < 0.0001), metastasis-free survival (p < 0.001), and menopausal status (p = 0.03) were the only significant factors for post-relapse survival.