National Surgical Adjuvant Study of Breast Cancer(N-SAS BC) 07 [RESPECT]

To investigate clinical positioning between trastuzumab (Herceptin) monotherapy (H group) and combination therapy of trastuzumab and chemotherapy (H+CT group) based on a randomized controlled trial in women over 70 years with human epidermal growth factor receptor type-2 (HER2) positive primary breast cancer.

Sex

Female

Minimum age

70 Years

Maximum age

80 Years

Inclusion Criteria:

1. Histologically diagnosed as invasive breast cancer and received curative operation for primary breast cancer.
2. Stage: 1 (tumor size \[pT\] \> 0.5 cm), 2A, 2B or 3A/ M0
3. Female between 70 and 80 years old
4. Primary region is HER 2 positive: either 3+ overexpression by IHC or positive by FISH
5. Baseline left ventricular ejection fraction (LVEF) is ≥55% measured by echocardiography or MUGA scan within 4 weeks before registration.
6. PS: 0-1 (ECOG)
7. Sufficient organ function meeting following criteria within 4 weeks before registration:

   * Leukocyte ≥2500 mm3
   * Neutrophil ≥1500 mm3
   * Platelet ≥100 000 mm3
   * Serum total bilirubin ≤2.0 x upper limit of normal (ULN)
   * ALT (GPT) or AST (GOT) ≤2.5 x ULN
   * Serum creatinine ≤2.0 x ULN
   * ALP ≤2.5 x ULN
8. No previous endocrine therapy or chemotherapy for breast cancer
9. Signed written informed consent

Exclusion Criteria:

1. Active multiple primary cancer (synchronous multiple primary cancer and invasive cancer of other organs)
2. Postoperative histological axillary lymph node metastasis ≥4
3. Axillary lymph node is not histologically evaluated
4. Histologically confirmed positive margin in breast conservation surgery (evaluation of margin status is based on policy of site)
5. History of drug-related allergy which could hinder planned treatment
6. Any history or complication of following cardiac disorders

   * History of congestive heart failure, cardiac infarction
   * Complication requires treatment such as: ischemic cardiac disorder, arrhythmia, valvular heart disease
7. Poorly controlled hypertension (ex. Systolic arterial pressure ≥180 mmHg or diastolic blood pressure ≥100 mmHg)
8. Poorly controlled diabetes
9. Continuous visit to a medial institution is considered difficult due to deterioration of activity of daily living (ADL)
10. Difficult to participate in the trial because of psychiatric disorder or psychiatric symptoms
11. Ineligible to the trial based on decision of an investigator

• DERIVEDNozawa K, Sawaki M, Uemura Y, Tsuneizumi M, Takano T, Gondo N, Hara F, Harao M, Toyama T, Taira N, Vivancos A, Perou CM, Sanfeliu E, Braso-Maristany F, Parker JS, Buckingham W, Pare L, Villacampa G, Marin-Aguilera M, Villagrasa P, Prat A, Iwata H. HER2DX in older patients with HER2-positive early breast cancer: extended follow-up from the RESPECT trial of trastuzumab +/- chemotherapy. Nat Commun. 2025 Nov 4;16(1):9585. doi: 10.1038/s41467-025-65599-x. PMID 41188218
• DERIVEDHagiwara Y, Sawaki M, Uemura Y, Kawahara T, Shimozuma K, Ohashi Y, Takahashi M, Saito T, Baba S, Kobayashi K, Mukai H, Taira N. Impact of chemotherapy on cognitive functioning in older patients with HER2-positive breast cancer: a sub-study in the RESPECT trial. Breast Cancer Res Treat. 2021 Aug;188(3):675-683. doi: 10.1007/s10549-021-06253-0. Epub 2021 Jun 2. PMID 34080094
• DERIVEDTaira N, Sawaki M, Uemura Y, Saito T, Baba S, Kobayashi K, Kawashima H, Tsuneizumi M, Sagawa N, Bando H, Takahashi M, Yamaguchi M, Takashima T, Nakayama T, Kashiwaba M, Mizuno T, Yamamoto Y, Iwata H, Ohashi Y, Mukai H, Kawahara T; RESPECT Study Group. Health-Related Quality of Life With Trastuzumab Monotherapy Versus Trastuzumab Plus Standard Chemotherapy as Adjuvant Therapy in Older Patients With HER2-Positive Breast Cancer. J Clin Oncol. 2021 Aug 1;39(22):2452-2462. doi: 10.1200/JCO.20.02751. Epub 2021 Apr 9. PMID 33835842
• DERIVEDSawaki M, Taira N, Uemura Y, Saito T, Baba S, Kobayashi K, Kawashima H, Tsuneizumi M, Sagawa N, Bando H, Takahashi M, Yamaguchi M, Takashima T, Nakayama T, Kashiwaba M, Mizuno T, Yamamoto Y, Iwata H, Kawahara T, Ohashi Y, Mukai H; RESPECT study group. Randomized Controlled Trial of Trastuzumab With or Without Chemotherapy for HER2-Positive Early Breast Cancer in Older Patients. J Clin Oncol. 2020 Nov 10;38(32):3743-3752. doi: 10.1200/JCO.20.00184. Epub 2020 Sep 16. PMID 32936713