Oncology | GileadPro

TNBC accounts for approximately 15% of all breast cancers and is diagnosed more often in young and premenopausal women.

TNBC is considered particularly aggressive: approximately 40% of patients develop metastases (metastatic TNBC, mTNBC) after initial treatment. The long-term survival rate for mTNBC patients is low. Amongst the factors to which this poor prognosis is attributable is the fact that the targeted therapies which are helpful against other types of breast cancer are ineffective in TNBC. Although TNBC and mTNBC do respond to chemotherapy, they also tend to become resistant or refractory to it. TNBC/mTNBC recurs approximately twice as quickly as other breast cancer types.⁵ In recent years, the use of novel antibody drug conjugates (ADCs) for mTNBC treatment has shown promising results, providing more treatment options and giving hope to mTNBC patients.⁶

HR+/HER2- BC accounts for approximately 70% of all breast cancers, making it the most common breast cancer subtype. HR+/HER2- BC generally has a more favorable prognosis than other BC subtypes.^7,8

The median 5-year survival rate of patients with metastatic BC (mBC) is 34%.⁹ The overexpression of hormone receptors in this subtype allows estrogen and progesterone to promote tumor growth and proliferation. Therefore, endocrine therapy (ET) is usually used as standard treatment in patients with HR+/HER2- mBC, combined with CDK4/6 inhibitors or targeted therapy when appropriate.^10-12 After progressing on ET, treatment for HR+/HER2- mBC gets increasingly challenging. Treatment options are largely limited to different single-agent chemotherapy regimens.¹³ However, median overall survival with chemotherapy after ET resistance is only about 1 year and decreases with each additional chemotherapy regimen. Therefore, patients with endocrine-resistant HR+/HER2- mBC need alternative treatment options that prolong survival and maintain quality of life.^13-14

In recent years, the use of novel antibody drug conjugates (ADCs) for HR+/HER2- mBC treatment has shown promising results, providing more treatment options and giving hope to HR+/HER2- mBC patients.¹⁴

HER2+ BC accounts for approximately 15% of all breast cancers.⁹ It is characterized by an overexpression of the HER2 gene. HER2+ BC is known to be an aggressive type of breast cancer and used to be associated with a very poor prognosis. HER2 targeting treatment options, however, have greatly improved the prognosis of this BC subtype. Consequently, the HER2+ BC 5-year survival rate is now close to 90% for early BC and up to 45% for metastatic BC. Treatments vary from chemotherapy to different targeted agents, if applicable.^9,15