Page 76 - HA Convention 2015

Masterclasses

MC1.1 Personalised Medicine on Cancer Treatment 13:15 Convention Hall A

Monday, 18 May How Molecular Diagnostics and Targeting Therapies Have Revolutionised Treatments for Breast Cancer
Ngan RKC
Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong

Despite a rising age-standardised incidence of breast cancer, the commonest female cancer in Hong Kong with more
than 3,500 new cases in 2012, the age-standardised mortality has remained steady over the past decade. Traditionally the
pathological tumour grade (differentiation of cancer cells) and clinical stage of breast cancers (size of primary tumour and
evidence of spread to regional lymph nodes or distant organs) are the only key prognostic factors of survival, and hormone
receptor status the predictive factor for treatment benefit to adjuvant hormone therapy.

In the era of molecular medicine, the advent in molecular diagnostics has helped to delineate specific types of breast
cancers such as Human Epidermal Growth Factor Receptor 2 (HER2) positive or triple negative cancers, better characterise
their biological behaviour, and predict their susceptibility to specific targeted therapy or chemotherapy regimens. Use of
genomic tests has also refined the algorithm for triaging patients to receive potentially toxic chemotherapy by predicting their
risk of recurrence with or without receiving chemotherapy. Young patients with breast cancer (BRCA) gene, when confirmed
by genetic test, will be managed with specific surgical strategy and surveillance policy due to their propensity to develop
second cancers in the same or contralateral breast, and in the ovaries. While most of the existing targeting agents have been
successfully engineered for and improved survival of patients with HER2 positive breast cancers, other targeting agents
capitalising on other cellular pathways cross-talking with the hormone receptor-related pathways, such as phosphoinositide
3-kinase (PI3K) inhibitors and cyclin-dependent kinase (CDK) 4/6 inhibitors, have been shown to benefit metastatic hormone
receptor positive breast cancers when they are given together with hormones. Although most of such emerging targeting
agents are now mainly tested in patients with incurable metastatic cancers, such agents may closely follow the footsteps
of anti-HER2 targeting agents and make their way to the adjuvant setting when they can be used to supplement the current
adjuvant systemic therapies to reduce recurrences and ultimately improve survival.

MC1.2 Personalised Medicine on Cancer Treatment 13:15 Convention Hall A

HOSPITAL AUTHORITY CONVENTION 2015 A Generic Tumour Marker for All Cancers
Chan AKC
Department of Chemical Pathology, The Chinese University of Hong Kong, Hong Kong

Tumour-derived DNA is present in the plasma of cancer patients. Detection of cancer-associated molecular changes in
plasma DNA represents an attractive way for the detection and monitoring of cancers. Using massively parallel sequencing,
cancer-associated copy number aberrations (CNAs), single nucleotide mutations and aberrant methylation can be detected
in the plasma DNA of cancer patients. As these genetic and epigenetic changes are present in all types of cancers, this
approach can be used as a generic tumour marker for all types of cancer. Furthermore, we have also characterised the
physical properties of plasma DNA in cancer patients and show that the DNA molecules derived from the tumour tissues are
shorter than those derived from non-malignant tissues. In addition, using plasma Epstein-Barr virus DNA in nasopharyngeal
carcinoma as a model, we have also explored the potential application of plasma DNA tumour marker for screening of early
cancers in asymptomatic individuals.

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