Effect of Endocrine Therapy Duration on Clinical Outcome of Patients With HR+ Intraductal Carcinoma of the Breast

Study Overview
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Brief Summary
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This study will investigate the relationship between the endocrine therapy and the survival of patients with hormone receptor positive intraductal carcinoma of the breast, and the optimal duration of medication. This study will also analyze the risk factors of recurrence and metastasis of hormone receptor positive intraductal carcinoma of the breast and establish a prognosis model to further clarify the specific reasons for recurrence and metastasis, adverse reactions, and drug withdrawal in patients with hormone receptor positive intraductal carcinoma of the breast after endocrine therapy.

Detailed Description
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Intraductal carcinoma of the breast accounts for 20% of newly diagnosed breast cancer. In addition to necessary surgical treatment, 5-year endocrine therapy is also essential for patients with hormone receptor positive ductal carcinoma of the breast. Commonly used drugs include selective estrogen receptor modulators (Tamoxifen, Toremifene) and aromatase inhibitors (Exemestane, Anastrozole, Letrozole). Although these drugs can effectively reduce the recurrence and metastasis of ductal carcinoma of the breast, the adverse reactions of the above drugs significantly reduce the quality of life and treatment compliance of the patients. Therefore, the choice of endocrine therapy for intraductal carcinoma of the breast has been widely discussed. Is it possible for de-escalation of endocrine treatment intensity to reduce adverse reactions and improve patient compliance? Recently, a phase 3 clinical trial found that compared with placebo group, the adverse reactions of Tamoxifen group treated with 5 mg/d (conventional dose 20 mg/d) Tamoxifen for 3 years had less adverse reactions and achieved significant efficacy. This study revealed the reliable efficacy and safety of Tamoxifen, a low-dose drug for treatment of hormone receptor positive intraductal carcinoma of the breast. However, little is reported on the reasonable duration of Aromatase inhibitors for endocrine therapy in patients with intraductal carcinoma of the breast. This study will investigate the relationship between the endocrine therapy and the survival of patients with hormone receptor positive intraductal carcinoma of the breast, and the optimal duration of medication. This study will also analyze the risk factors of recurrence and metastasis of hormone receptor positive intraductal carcinoma of the breast and establish a prognosis model to further clarify the specific reasons for recurrence and metastasis, adverse reactions, and drug withdrawal in patients with hormone receptor positive intraductal carcinoma of the breast after endocrine therapy.

Official Title
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Effect of Endocrine Therapy Duration on Clinical Outcome of Patients With Hormone Receptor-positive Intraductal Carcinoma of the Breast: A Multicenter, Retrospective, Real-world Study

Conditions
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Breast Cancer

Intervention / Treatment
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* Drug: Tamoxifen
* Drug: Toremifene
* Drug: Anastrozole
* Drug: Letrozole
* Drug: Exemestane


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: (1)Female patients aged ≥ 18 years and ≤ 85 years (2)The primary lesions and lymph nodes of the breast must meet all of the following conditions: Histologically confirmed intraductal carcinoma of the breast, accompanied by microinvasion, with the infiltration range ≤ 1 mm; Have received radical resection or breast conserving surgery; Patients who have received breast conserving surgery must undergo pathological examination to confirm there is no residual cancer tissue on the cutting edge and receive postoperative radiotherapy within the prescribed dose and range; No lymph node metastasis (including micrometastasis) is detected by postoperative pathological examination; Immuno Immunohistochemical staining results are positive for estrogen receptor (ER) or progesterone receptor (PR), which is defined as ER or PR immunoreactivity intensity ≥1+ or expression percentage ≥ 1%. (3)A volunteer to participate in the study and willing to cooperate with follow-up Exclusion Criteria: (1)Patients with newly diagnosed metastatic breast cancer or other malignant tumors without breast intraductal carcinoma; (2) Patients who have other malignant tumors before the initial diagnosis of intraductal carcinoma of the breast (3) Patients who have received endocrine therapy with drugs including Toremifene, Tamoxifen, Anastrozole, Letrozole or Exemestane before the initial diagnosis of intraductal carcinoma of the breast (4) Patients who have a serious comorbidity or other comorbidities that interfere with the conduct of the study, or those who are considered not suitable for participation in this study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Drug Group<br>Endocrine therapy drugs include selective estrogen receptor modulators (Tamoxifen, Toremifene) and aromatase inhibitors (Anastrozole, Letrozole, Exemestane), which have been widely used in the adjuvant treatment of hormone receptor positive breast cancer. | Drug: Tamoxifen<br>* 20 mg/d, oral administration<br>Drug: Toremifene<br>* 60 mg/d, oral administration<br>Drug: Anastrozole<br>* 1 tablet (1 mg) per day, oral administration<br>Drug: Letrozole<br>* Adjuvant therapy with letrozole for 5 years or until the disease relapses. Patients who have received tamoxifen adjuvant therapy for 5 years should continue to take Letrozole until the disease relapses. The recommended dose of Letrozole tablets is one 2.5 mg tablet administered once a day, without regard to meals. For patients with advanced breast cancer, treatment with Letrozole should continue until tumor progression is confirmed. Patients with liver and/or renal dysfunction (creatinine clearance rate ≥ 10 mL/min) do not need to adjust the dosage.<br>Drug: Exemestane<br>* The recommended dose of Exemestane for adult and older patients with early and advanced breast cancer is one 25 mg tablet administered orally once a day after a meal. After 2-3 years of tamoxifen treatment, patients with early breast cancer should continue to use Tamoxifen in the case of no recurrence or contralateral breast cancer, until the completion of 5-year sequential adjuvant therapy with tamoxifen and exemestane. Patients with advanced breast cancer should continue to take Exemestane until the tumor progresses.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Disease-free survival up to 16 years | Disease-free survival refers to the time from the first disease-free day (i.e. the operation day) to the day at which relevant event occurs. | Time from the first disease-free day to the end of the last follow-up, assessed up to 16 years | 
| Invasive disease-free survival up to 16 years | Invasive disease-free survival refers to the time from the first disease-free day (i.e. the operation day) to the day at which intraductal carcinoma of the breast recurs. The recurrent diseases include ipsilateral or contralateral breast cancer, local and distant recurrence of breast cancer, and death due to any reason. | Time from the first disease-free day to the end of the last follow-up, assessed up to 16 years | 
| Distant disease-free survival up to 16 years | Distant disease-free survival refers to the time from the first disease-free day (i.e. the operation day) to the day at which distant metastasis occurs. | Time from the first disease-free day to the end of the last follow-up, assessed up to 16 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival up to 16 years | Overall survival refers to the first disease-free day to the time of death caused by any reason. | Time from the first disease-free day to the end of the last follow-up, assessed up to 16 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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breast cancer, hormone receptor, aromatase inhibitor, recurrence, metastasis