On October 31, 2025 (Friday), Dr. Lee Yu-chung, a clinical oncologist at the Hong Kong United Oncology Centre (HKUOC), was invited to share the latest understanding and breakthroughs in early breast cancer treatment at a patient education seminar organized by the Global Chinese Breast Cancer Coalition (GCBC).The lecture's theme is "Embracing Hope – New Insights into Early Breast Cancer," focusing on new trends in the treatment of hormone receptor-positive (HR+/HER2-) breast cancer, managing recurrence risk, and how innovative therapies such as CDK4/6 inhibitors can help patients reduce recurrence and extend survival.
Lecture Background
- Date:October 31, 2025 (Friday)
- Time:2:30 pm–3:30 pm
- Location:Shop 29C, Wing Yee Plaza, 609 Tai Nan West Street, Lai Chi Kok (near Exit B1 of Lai Chi Kok MTR Station)
- Organized by:Global Alliance of Chinese Breast Cancer Organizations (GCBC)
- Speaker:Dr. Li Yu Chung, Jacky (Specialist in Clinical Oncology, Hong Kong United Cancer Centre, HKUOC)
- Topic:Embracing Hope–A New understanding of Early Breast Cancer
Speaker Introduction: Dr. Li Yu Chung, Jacky (Hong Kong United Cancer Centre, HKUOC)
Qualifications and expertise
- Clinical Oncology Specialist
- Bachelor of Medicine and Surgeon General Practice (MBBS) from the University of Hong Kong
- Fellow of The Royal College of Radiologists (UK) FRCR (UK)
- Fellow of the Hong Kong College of Radiologists FHKCR
- Fellow of the Hong Kong Academy of Medicine (Radiology) FHKAM (Radiology)
Clinical focus and scope of concern
- Evidence-based personalized treatment planning and multidisciplinary team collaboration.
Clinical concepts
- Emphasis should be placed on patient education and risk-benefit communication, and treatment plans should be developed under the premise of safety and clinical needs.
- Respecting patient preferences and life goals, emphasizing continuous follow-up and interdisciplinary coordination
Brief Highlights
- Breast cancer in Hong Kong has the highest incidence of cancer among women (accounting for 28.6%), and more than 85% of patients are diagnosed at an early stage.
- Hormone receptor positive (HR+/HER2-) breast cancer accounts for about two-thirds of the total number of breast cancer in Hong Kong and is the most common subtype.
- The goal of early breast cancer treatment is to achieve a cure and reduce the risk of recurrence; even in patients without lymph node metastasis, there is still a 13% to 19% risk of recurrence within 5 to 20 years.
- CDK4/6 inhibitors combined with hormone therapy have been listed as an international first-level treatment recommendation, which can reduce the risk of relapse by 25% at 3 years and by 28.4% at 5 years.
- Treatment should be individualized, combining multiple approaches such as surgery、radiation therapy, and targeted therapy.
Overview and Statistics of breast cancer in Hong Kong
Breast cancer has the highest incidence rate among all cancers in women.
- According to local data from 2022, breast cancer accounts for 28.6% of all new cancer cases among women in Hong Kong, making it the most common type of cancer.
- One in every 14 women has a chance of developing invasive breast cancer in her lifetime.
- It ranks third in mortality rate (12.5%), after lung cancer and colorectal cancer.
More than 80% of patients were diagnosed with breast cancer at an early stage
- Thanks to the improvement of the breast cancer screening system, most patients in Hong Kong can be diagnosed at an early stage of cancer.
- 85.3%of patients were diagnosed at an early stage (stages I, II, and III).
- If breast cancer can be detected and diagnosed early, the patient's prognosis is usually better.
- The survival rates differ significantly among patients at different stages: the five-year survival rate for stage three is 76.2%, while for stage one it is as high as 99.3%.
Four major biological subtypes of breast cancer
Breast cancer can be divided into four main types based on receptor performance：
- Lumen type A (Luminal A)：HR+/HER2-, the tumor has a lower degree of malignancy, slower growth, and a better prognosis.
- Lumen type B (Luminal B)：Mainly HR+, some HER2+ or HER2-, the degree of malignancy is higher than that of lumen type A, the growth is faster, and the prognosis is poor.
- HER2 Overexpression Type: Tumors grow rapidly and are highly malignant, requiring targeted therapy.
- Triple negative type (TNBC)：Tumors that are negative for both hormone receptors (ER/PR) and HER2 are fast-growing and highly aggressive, with limited treatment options and a poor prognosis.
HR+/HER2-is the most common type of breast cancer in Hong Kong, accounting for about two-thirds of the total number of breast cancer.
In Hong Kong, 60% of breast cancer cases are hormone receptor-positive.
- According to figures from the Hong Kong Cancer Registry as of September 2024, of the 5,182 new cases diagnosed in 2022, 3,379 were classified as luminal A or luminal B type, with early-stage cases accounting for over 60%.
- The type and risk of breast cancer depend on its stage and a variety of other factors.
Early breast cancer: Risk factors for recurrence
Even in patients with early breast cancer, there is still a risk of recurrence. Factors that increase breast cancer recurrence include：
- Tumor size：Those with tumors larger than 2 cm are at high risk of recurrence
- Lymphatic metastasis：When the cancer spreads to the lymph nodes, the risk of recurrence is also higher
- Age：Young patients (less than 35 years old) have a higher risk of recurrence
- Tumor grading and proliferation index (Ki-67):High tumor grade and high Ki-67 index increase the risk of recurrence.
- BRCA gene mutation：HR+/HER2-patients with BRCA gene mutations have a higher risk of recurrence
What is a breast cancer patient with a high risk of recurrence?
According to the clinical definition, patients with a high risk of breast cancer recurrence include:
- There is 1 or more lymph node metastasis.
- Another situation，there are no lymph node metastases, and one of the following conditions is met:
- T4 (Tumor has invaded the skin or chest wall)
- T3 (Tumor size is 5 cm or larger)
- T2 (Tumor size is 2 to 5 cm) + other high-risk factors (including tumor grade and proliferation index (Ki-67), BRCA gene mutation, etc.)
Patients without lymph node metastasis are also at risk of recurrence
- About 1 in every 5 patients without lymph node metastasis relapse.
- Large-scale medical studies have indicated that even breast cancer patients in stages I and II without lymph node metastasis have a 13% to 19% risk of recurrence within 5 to 20 years.
- Patients without lymph node metastasis are also at risk of recurrence. Early patients should not take it lightly.
- Regardless of whether it is a high- or low-risk patient, any patient is at risk of recurrence.
- Even within 20 years after breast cancer treatment, patients still have a chance of recurrence.
Nearly half of HR+/HER2- early breast cancer patients still have a risk of recurrence within 20 years of diagnosis.
- Since there is currently no cure for metastatic breast cancer, it is crucial to prevent recurrence.
- Although early breast cancer treatment aims at cure, the risk of recurrence is still a major challenge.
- HR+/HER2-Recurrence of breast cancer occurs in about half of cases within five years, and the risk of recurrence can last for more than 20 years.
Early-stage breast cancer treatment: surgery and adjuvant therap
Treatment goals for early-stage hormone-positive breast cancer
- The main goal is to cure and reduce the risk of recurrence.
- Combining multiple options such as surgery, radiation therapy, hormone therapy and targeted therapy
Surgical treatment options for breast cancer
- Breast-conserving surgery: This involves removing the tumor and a portion of the surrounding normal tissue, while preserving most of the breast. For most patients with early-stage breast cancer, breast-conserving surgery combined with radiotherapy is the preferred standard treatment.
- Total mastectomy：Remove the entire breast, suitable for patients with larger tumors.
Non-surgical treatment options for breast cancer
- Radiation therapy：Commonly used after breast retention surgery to kill residual cancer cells
- Hormone therapy：Suitable for HR+ patients, inhibits estrogen and stimulates the growth of cancer cells
- Targeted therapy:Suitable for patients with specific biomarkers, such as HER2+ patients, targeted drugs for HER2 can be used
- Adjuvant chemotherapy：Used to eliminate cancer cells that may remain in the body
Postoperative treatment required by different breast cancer patients
The tumor size and lymph node involvement of patients with early breast cancer are important factors in determining adjuvant treatment after surgery.：
- Hormone receptor-positive (HR+) patients:Postoperative hormone therapy is required
- HER2-positive patients:Post-operative targeted therapy is required.
- Patients at high risk of recurrence (e.g., those with high tumor grade, high Ki-67 index, or lymph node involvement):Post-operative chemotherapy and comprehensive treatment are required.
- Those whose physical condition allows treatment：Adjust the treatment plan according to personal physique and health status
Hormone therapy: the most traditional adjuvant therapy option
At present, the types of hormone therapy are roughly divided into three categories：
- Anti-estrogen drugs：Blocking estrogen from binding to estrogen receptors on breast cancer cells to slow down the growth of breast cancer tumors is the oldest hormonal cancer treatment drug. It is suitable for patients before and after menstruation.
- Aromatase Inhibitors (Aromatase Inhibitors)：After menopause, the ovaries stop producing estrogen, but the adrenal glands first produce androgens, which are then converted into estrogen by an enzyme called aromatase. Therefore, taking medication to inhibit aromatase can block the conversion process of estrogen, lowering estrogen levels and thus reducing the binding of estrogen to its receptors on breast cancer cells, thereby inhibiting tumor growth. This treatment is suitable for postmenopausal patients (premenopausal patients require concurrent ovarian suppression therapy).
- Ovarian targeted therapy：Drug treatment, surgical resection or electrotherapy are performed on the ovaries to block their production of estrogen. Only suitable for patients who have not received menstruation.
CDK4/6 Inhibitors: A major breakthrough in early breast cancer treatment.
What are CDK4/6 inhibitors?
- CDK4/6 inhibitors are a new type of targeted drug that can suppress cyclin-dependent kinases.
- In hormone receptor-positive breast cancer, cancer cell division is particularly dependent on the CDK4/6 signaling pathway.
- Therefore, blocking the CDK4/6 cell signaling pathway is particularly crucial in the treatment of these types of cancers.
CDK4/6 inhibitors have been confirmed to be used as adjuvant therapy for early HR+/HER2-breast cancer
Studies have shown that combined use of CDK4/6 inhibitors + hormone therapy：
- 25% reduction in risk of recurrence after 3 years%
- The risk of recurrence decreased by 28.4% after 5 years.
- Significantly improved invasive disease-free survival index (IDFS)
International treatment guidelines also recommend CDK4/6 inhibitors as adjuvant therapy for early HR+/HER2-breast cancer
- American Oncology Clinical Practice Guidelines (NCCN)：The combination of CDK4/6 inhibitors and hormone therapy is included as a Category 1 treatment recommendation, applicable to patients with and without lymph node metastasis (tumor size greater than 5 cm; or tumor size between 2 and 5 cm with specific risk factors).
- American Society of Clinical Oncology (ASCO)：It is recommended to use "combined use of CDK4/6 inhibitors and hormone therapy" as adjuvant therapy.
- U.S. Food and Drug Administration (FDA)：Approved "combined use of CDK4/6 inhibitors and hormone therapy".
- The European Medicines Agency (EMA), the British National Institute for Health and Clinical Excellence (NICE)：It is recommended to use "combined use of CDK4/6 inhibitors and hormone therapy" as an adjuvant treatment for early HR+/HER2-breast cancer with a high risk of recurrence.
Adjuvant therapy is added after the initial treatment to help remove residual cancer cells and reduce the risk of recurrence.
Adjuvant CDK4/6 inhibitor treatment
CDK4/6 inhibitors currently used in early breast cancer mainly include：
- Adjuvant Abemaciclib treatment：
- Indications：Lymph node-positive HR+/HER2- early breast cancer (EBC); with 4 or more lymph node metastases; or with 1 to 3 lymph node metastases and tumor grade G3, or tumor size 5 cm or larger, or Ki-67 index 20% or higher.
- Treatment time：2 years
- Main side effects：Gastrointestinal toxicity (such as diarrhea)
- Adjuvant Ribociclib treatment：
- Indications：HR+/HER2- early breast cancer (EBC); with one or more lymph node metastases; or without lymph node metastasis but with high-risk features (T3 or T4; or T2 with tumor grade G3; or T2 with tumor grade G2 and high risk [Ki-67 index of 20% or higher, or Oncotype DX breast cancer recurrence risk score of 26 or higher, or other high-risk genetic features]).
- Treatment time：3 years
- Main side effects：Neutropenia, liver-related adverse reactions, and QT interval prolongation.
Advanced breast cancer: Treatment goals and Options
Treatment goals for advanced hormone-positive breast cancer
- Extend overall survival time
- Control disease progress
- Improve quality of life
Treatment of advanced breast cancer
- Hormone therapy
- Targeted therapy
- Chemotherapy
- Radiotherapy
Application of CDK4/6 inhibitors in advanced breast cancer
- CDK4/6 inhibitors combined with hormone therapy have become the standard treatment for advanced HR+/HER2-breast cancer, which can significantly extend the overall survival period.
- Clinical data show that Ribociclib (MONALEESA series studies), Abemaciclib (MONARCH series studies), and Palbociclib (PALOMA series studies) in combination with endocrine therapy all significantly improve overall survival compared to the control group. Clinical data show that Ribociclib (MONALEESA series studies), Abemaciclib (MONARCH series studies), and Palbociclib (PALOMA series studies) in combination with endocrine therapy all significantly improve overall survival compared to the control group.
- Among them, Ribociclib had a median total survival of 63.9 months in the MONALEESA-2 study.
- International treatment guidelines such as those from NCCN and ESMO explicitly recommend the combination of CDK4/6 inhibitors with hormone therapy as standard treatment for HR+/HER2- advanced breast cancer.
Patient notes and treatment recommendations
- Patients should actively receive treatment, maintain good living habits, follow the doctor's instructions to actively receive treatment, and follow up regularly to keep abreast of the progress of treatment to help reduce the risk of recurrence.
- There are different treatment options for breast cancer. Patients should discuss with the attending doctor to choose the most suitable treatment plan.
- Early-stage treatment focuses on the prevention of recurrence, while late-stage treatment aims to prolong survival.
- International treatment guidelines recommend the combination of CDK4/6 inhibitors and hormone therapy as the standard treatment option for HR+/HER2-early or advanced breast cancer.
- Patients must take the initiative to participate in treatment decisions, discuss with their doctors, and choose a plan according to their physical condition, condition, and personal needs.
FAQ
- What are CDK4/6 inhibitors?
- CDK4/6 inhibitors are a new type of targeted drug that inhibits cyclin-dependent kinases, blocking cancer cell division, and are particularly effective against hormone receptor-positive (HR+) breast cancer.
- Am I suitable for CDK4/6 inhibitor treatment for everyone?
- It is primarily applicable to HR+/HER2- breast cancer patients, especially early-stage patients or late-stage metastatic patients with a high risk of recurrence. Specific applicability needs to be assessed by a physician based on tumor stage, receptor status, recurrence risk, and physical condition.
- What are the side effects of CDK4/6 inhibitors?
- Common side effects vary depending on the medication. Abemaciclib primarily causes gastrointestinal toxicity (such as diarrhea); Ribociclib mainly causes neutropenia, liver function abnormalities, and QT interval prolongation. Doctors will regularly monitor blood counts and liver function and adjust the dosage as needed.
- Is there still a risk of recurrence in early-stage breast cancer patients without lymph node metastasis?
- Yes. Studies show that even early-stage patients without lymph node metastasis still have a 13% to 19% risk of recurrence within 5 to 20 years. The risk of recurrence is even higher if the tumor is large, high-grade, has a high Ki-67 index, or has a BRCA gene mutation.
- What is hormone receptor positive (HR+) breast cancer?
- HR+/HER2- refers to breast cancer cells that are positive for estrogen receptors (ER) or progesterone receptors (PR). These cancer cells grow in response to stimulation by estrogen or progesterone. HR+/HER2- is the most common type of breast cancer in Hong Kong, accounting for about two-thirds of all cases.
- What is the difference between Abemaciclib and Ribociclib?
- Both are CDK4/6 inhibitors, but they differ in indications, treatment duration, and side effects. Abemaciclib has a treatment duration of two years, with diarrhea as the main side effect; Ribociclib has a treatment duration of three years, with leukopenia and liver function abnormalities as the main side effects. Doctors will choose the appropriate medication based on the patient's specific condition.
Three questions to prepare before seeing a doctor
- What type of breast cancer does my breast cancer belong to (receptor status, stage, grade, Ki-67 index, etc.)?
- Is my risk of recurrence high risk or low risk? Is it suitable for CDK4/6 inhibitor treatment?
- The benefits, common side effects and follow-up arrangements of various feasible treatment options (hormone therapy, CDK4/6 inhibitors, chemotherapy, etc.)?
Personalized treatment approach of Hong Kong United Cancer Centre (HKUOC)
- Patient-centered approach:Maintain appropriate communication with the attending physician, provided that clinical needs and safety are met (e.g., by creating a separate WhatsApp group for non-urgent matters).
- Personalized plans:plans are developed based on pathological and molecular results, staging, comorbidities, and personal preferences.
- Financial support:Provide medication assistance and clinical research information (if applicable) on a case-by-case basis, without compromising the physician's independent professional judgment.
Inquiries and Appointments (Hong Kong United Cancer Centre HKUOC)
- Telephone：+852 2386 8002
- WhatsApp：+852 5518 2992
- Website:www.hkuoc.hk
- Email：Enquiry@hkuoc.hk
- Address：Rooms 01–06, 20th Floor, 238 Nathan Road, Jordan, Kowloon (Jordan MTR Station Exit E)
Early breast cancer: New trends in treatment
- Staging and prognosis：The five-year survival rate of the first phase was 99.3%, and the third phase was 76.2%; early detection is essential.
- Recurrence risk management：The risk of recurrence of HR+/HER2-breast cancer can last for 20 years and requires long-term monitoring.
- CDK4/6 inhibitors：Ribociclib and Abemaciclib have been included in the NCCN's first-line treatment recommendations, reducing the risk of recurrence by 25% at 3 years and 28.4% at 5 years.
- Surgery and radiotherapy：Breast-conserving surgery followed by radiotherapy is the preferred treatment for early-stage breast cancer; total mastectomy is suitable for larger tumors or multiple lesions.
- Adjuvant therapy integration：Formulate personalized plans based on receptor status and recurrence risk, combining hormonal therapy, targeted therapy, chemotherapy, etc.
Advanced breast cancer: Classification and New Trends
- Treatment goals：Prolong the overall survival period, control the progress of the disease, and improve the quality of life.
- First-line treatment:CDK4/6 inhibitors combined with hormone therapy are the standard regimen for HR+/HER2-advanced breast cancer; Ribociclib (MONALEESA-2 study) has a median total survival of 63.9 months.
- Second-line treatment:Treatment strategies can be adjusted based on drug resistance mechanism and medical history, and chemotherapy, other targeted drugs, or clinical studies can be considered.
- Other targeted therapies：Including mTOR inhibitors, PIK3CA inhibitors, etc., suitable for patients with specific gene mutations.
Reference (excerpt)
- NCCN Clinical Practice Guidelines 2024–2025：Breast Cancer
- ESMO Guidelines 2023–2024：Breast Cancer
- Johnston SR, et al. N Engl J Med. 2024;390:1080-1091
- Crown J, et al. ESMO 2025. Oral LBA14
- Pan H, et al. N Engl J Med. 2017;377:1836-1846
- Foldi J, et al. J Clin Oncol. 2019;37:1365-1369
- Pedersen RN, et al. J Natl Cancer Inst. 2022;114:391-399
- Hong Kong Hospital Authority Cancer Registry. Breast cancer factsheet 2022
- Centre for Health Protection, Department of Health, HKSAR. Common cancer-breast cancer
- Hortobagyi GN, et al. N Engl J Med. 2016;375:1738-1748
- Goetz MP, et al. J Clin Oncol. 2017;35:3638-3646
- Tripathy D, et al. Lancet Oncol. 2018;19:904-915
For more up-to-date information on breast cancer treatment in Hong Kong, please refer to the following authoritative resources：
- Hong Kong Breast Cancer Foundation: Free support services and patient education materials.
- Hong Kong Cancer Fund: Cancer patient support service and information platform.
