Weekly paclitaxel improves pathologic complete remission in operable breast cancer when compared with paclitaxel once every 3 weeks.
OBJECTIVE
To determine the impact a change in schedule of paclitaxel administration from once every 3 weeks to frequent administration would have on the pathologic complete response (pCR) rate in the breast and lymph nodes for patients with invasive breast cancer treated with primary systemic chemotherapy (PST).


METHODS
Patients with clinical stage I-IIIA breast cancer were randomly assigned to receive PST of paclitaxel doses administered either weekly (for a total of 12 doses of paclitaxel) or once every 3 weeks (four cycles), followed by four cycles of fluorouracil/doxorubicin/cyclophosphamide (FAC) in standard doses every 3 weeks. Two different doses of paclitaxel were used based on lymph node status defined by ultrasound and fine needle aspiration. Clinical response and extent of residual disease in the breast and lymph nodes was assessed after completion of all chemotherapy.


RESULTS
A total of 258 patients were randomly assigned to receive doses of paclitaxel administered either weekly or once every 3 weeks, followed by FAC. Of these 258 patients, 110 patients had histologic lymph node involvement and 148 patients had clinical N0 disease. Weekly paclitaxel followed by FAC was administered to 127 patients and once-every-3-weeks paclitaxel followed by FAC was administered to 131 patients. Clinical response to treatment was similar between groups (P = .25). Patients receiving weekly paclitaxel had a higher pCR rate (28.2%) than patients treated with once-every-3-weeks paclitaxel (15.7%; P = .02), with improved breast conservation rates (P = .05).


CONCLUSIONS
The change in schedule of paclitaxel from once every 3 weeks to a more frequent administration significantly improved the ability to eradicate invasive cancer in the breast and lymph nodes.
Green
Marjorie C
MC
The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd, Box 424, Houston, TX 77030, USA. mgreen@mdanderson.org
Buzdar
Aman U
AU
Smith
Terry
T
Ibrahim
Nuhad K
NK
Valero
Vicente
V
Rosales
Marguerite F
MF
Cristofanilli
Massimo
M
Booser
Daniel J
DJ
Pusztai
Lajos
L
Rivera
Edgardo
E
Theriault
Richard L
RL
Carter
Cynthia
C
Frye
Debra
D
Hunt
Kelly K
KK
Symmans
W Fraser
WF
Strom
Eric A
EA
Sahin
Aysegul A
AA
Sikov
William
W
Hortobagyi
Gabriel N
GN
D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage* / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery; D003520:Cyclophosphamide / Q000008:administration & dosage; D004317:Doxorubicin / Q000008:administration & dosage; D004334:Drug Administration Schedule; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D017239:Paclitaxel / Q000008:administration & dosage* / Q000627:therapeutic use*; D016896:Treatment Outcome
D018931:Antineoplastic Agents, Hormonal; D004317:Doxorubicin; D003520:Cyclophosphamide; D017239:Paclitaxel; D005472:Fluorouracil