A phase II study on metastatic breast cancer patients treated with weekly vinorelbine with or without trastuzumab according to HER2 expression: changing the natural history of HER2-positive disease.
OBJECTIVE
To observe whether in pretreated metastatic breast cancer patients with HER2-positive disease vinorelbine plus trastuzumab can produce different overall response rate (ORR), time to progression (TTP), and overall survival (OS) from women with HER2-negative tumors treated with vinorelbine alone.


METHODS
Between June 2000 and January 2004, 68 consecutive women were enrolled: 33 patients received vinorelbine (V) alone, while 35 patients were given trastuzumab plus vinorelbine (T+V) according to HER2 expression determined by immunohistochemistry. In tumors scored +2, HER2 gene amplification was determined by fluorescence in situ hybridization.


RESULTS
In patients treated with V (HER2-negative tumors) the ORR was 27.3%, while in those given T+V (HER2 positive tumors) the ORR was 51.4%. The median duration of response was 8 months for women treated with V and 10 months for those who received T+V. Patients given T+V had a longer TTP (9 months) and OS (27 months) than those receiving V alone (6 months and 22 months respectively). Toxicity was mild in both groups. Concerning cardiotoxicity in T+V group, 7 patients (20%) had left ventricular systolic disfunction.


CONCLUSIONS
Our data suggest that trastuzumab can change the natural history of HER2-positive metastatic breast cancer. In fact, when treated with trastuzumab, women with HER2-positive disease had better prognosis than patients with HER2-negative tumors. Conducting a formal phase III trial comparing vinorelbine alone vs vinorelbine plus trastuzumab in HER2-positive metastatic breast cancer women could be debatable.
Papaldo
P
P
Division of Medical Oncology A, Regina Elena Cancer Institute, Rome, Italy.
Fabi
A
A
Ferretti
G
G
Mottolese
M
M
Cianciulli
A M
AM
Di Cocco
B
B
Pino
M S
MS
Carlini
P
P
Di Cosimo
S
S
Sacchi
I
I
Sperduti
I
I
Nardoni
C
C
Cognetti
F
F
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D061067:Antibodies, Monoclonal, Humanized; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy*; D004334:Drug Administration Schedule; D005260:Female; D018734:Genes, erbB-2; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D000068878:Trastuzumab; D014747:Vinblastine / Q000008:administration & dosage / Q000031:analogs & derivatives; D000077235:Vinorelbine
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D014747:Vinblastine; D000068878:Trastuzumab; D000077235:Vinorelbine