Herceptin plus docetaxel/cyclophosphamide (HER TC) adjuvant therapy—a non-anthracycline-containing regimen—was tolerable with acceptable safety for lower risk patients with HER2-positive early breast cancer, according to a large Phase II study.
Herceptin plus docetaxel/cyclophosphamide (HER TC) adjuvant therapy—a non-anthracycline-containing regimen—was tolerable with acceptable safety for lower risk patients with HER2-positive early breast cancer, according to a large Phase II study that found no cases of congestive heart failure and only four discontinuations for cardiac reasons among 262 patients enrolled in the trial.
HER TC builds on the TC regimen, a non-anthracycline-containing regimen previously shown by Dr. Jones and colleagues to be superior to standard doxorubicin/cyclophosphamide (AC) for disease-free and overall survival in early breast cancer. At last year’s SABCS, Dr. Jones also reported that TC was superior to AC in cancers that overexpress HER2.
“We chose to study our TC regimen coupled with Herceptin as a potential effective and shorter regimen—only four cycles—for lower risk patients with HER2-positive early breast cancer,” Dr. Jones commented.
The study enrolled 262 patients with a median age of 55 years (range, 30-75 yeas). More than 80% were Caucasian, 89% were ECOG Performance Status 0, and 76.7% were node-negative. Among the 23.3% of node-positive patients, most had one or two positive nodes. About 44% were both estrogen receptor and progesterone receptor positive (ER+/PgR+), 19.8% were ER+/PgR-, 33.1% were negative for both hormone receptors, and 3% were ER-/PgR+.
Dr. Jones noted that 22.9% of tumors were < 1cm, and 47.3% were 1-2cm. Unlike many trials of early breast cancer, the trial also included women with bigger tumors (29.4%, tumors 2.1-5.0cm).
Grade 4 neutropenia was 37%, and the rate of all grades of febrile neutropenia of all grades was 6%; six of these patients received prophylactic white blood cell growth factors. An additional 145 patients were given white blood cell growth factors at some time during treatment. Rates of Grade 3 and 4 hematologic adverse events were low, with the exception of neutropenia (49.4%) and leukopenia (15.8%). Rates on grade 3 and 4 non-hematologic adverse events were very low (under 2%), except for fatigue (3.5%) and diarrhea (3.5%). Sixteen patients discontinued treatment due to adverse events (four for cardiac reasons, as stated above. Two patients died—one with neutropenia and one with respiratory distress syndrome (cause unknown).