Systemic therapy in patients with node-negative breast cancer. A commentary based on two National Surgical Adjuvant Breast and Bowel Project (NSABP) clinical trials.
OBJECTIVE
To determine whether in the previous National Surgical Adjuvant Breast and Bowel Project (NSABP) studies of node-negative breast cancer there were either cohorts of patients with a prognosis favorable enough to preclude using systemic therapy or subsets of patients who failed to benefit from the treatments.


METHODS
Randomized clinical trials with stratification after surgery.


METHODS
NSABP trials at institutions in the United States and Canada.


METHODS
Data were collected on 731 eligible patients (Protocol B-13) with estrogen-receptor-negative tumors who randomly received either no therapy after surgery or sequential methotrexate and fluorouracil (M----F) followed by leucovorin. Data were also collected on 2834 patients (Protocol B-14) with estrogen-receptor-positive tumors who randomly received either placebo or tamoxifen treatment. The percentage of patients surviving disease-free was determined through 4 years of follow-up using life-table estimates.


METHODS
Protocol B-13 patients received 12 courses of M----F given intravenously on days 1 and 8 every 4 weeks. Leucovorin therapy was begun 24 hours after M----F administration. Protocol B-14 patients received 5-year treatment with either tamoxifen (10 mg twice daily by mouth) or placebo.


RESULTS
When the outcome of untreated patients in either trial was related to the stratification variables, women were found to have a disease-free survival of less than 80% through 4 years of follow-up. This percentage is apt to decrease because the probability of treatment failure increases with time. In both trials, all subsets of women benefited from M----F or tamoxifen therapy.


CONCLUSIONS
The disease-free survival of all cohorts of node-negative patients with estrogen-receptor-negative or estrogen-receptor-positive tumors was poor enough to justify systemic treatment. The benefits of the therapies used are insufficient to eliminate the need for assessing putatively better regimens.
Fisher
B
B
National Surgical Adjuvant Breast and Bowel Project Headquarters, Pittsburgh, Pennsylvania.
Redmond
C
C
Wickerham
D L
DL
Wolmark
N
N
Bowman
D
D
Couture
J
J
Dimitrov
N V
NV
Margolese
R
R
Legault-Poisson
S
S
Robidoux
A
A
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy* / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D005500:Follow-Up Studies; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008727:Methotrexate / Q000008:administration & dosage; D016032:Randomized Controlled Trials as Topic; D011960:Receptors, Estrogen / Q000032:analysis; D016019:Survival Analysis; D013629:Tamoxifen / Q000627:therapeutic use*
D011960:Receptors, Estrogen; D013629:Tamoxifen; D002955:Leucovorin; D005472:Fluorouracil; D008727:Methotrexate