Prof. Dr Rohaizak Muhammad, Breast & Endocrine Consultant, UKMMC
Introduction: Breast cancer is one the most common cancer among female worldwide. It is also the most common cancer among female in Malaysia with reported incidence to National Cancer Registry of new cases in 2006 to be 3525, giving an Age-standardized Incidence ratio of 39.3 per 100,000 populations. According to the ethnicity, the Chinese has the highest incidence, followed by Indian and Malay but this might not reflect the true racial distribution as many new cases are not reported. In many developed country, the disease is most prevalent among the older women but unfortunately, in Malaysia, the peak age specific incidence was at 50-59 years for Malays and Chinese and 60-69 years in Indian.
Figure 1 Figure 2
Figure 1. Ten most frequent cancer in Peninsular Malaysia 2006
Figure 2. Ten most frequent cancer in female in Peninsular Malaysia 2006
Definition : When we talk about breast cancer, we are referring to the common types of breast cancer which are infiltrating ductal carcinoma and infiltrating lobular carcinoma. There are also cancer of the breast, not arising from lactiferous duct or lobules such as Cystosarcoma phylloides (Phylloides tumour), angiosarcoma of the breast or malignant metastasis to the breast.
Investigation : The most important is “Tripple Assessment” which includes Clinical Examination, Cytology/Histology and Radiology (Mammogram and/or Ultrasound). Mammogram is performed mainly for symptomatic patients who are more than 35 years of age as the younger patient tend to have dense breasts. For these group of patients, ultrasound will be more sensitive in picking up lesion in the breast. For asymptomatic patients, the recommendation is to start screening at the age of 40, to be done 1-2 yearly.
Treatment : Primary treatment for early breast cancer is surgery either in form of breast conserving surgery(BCS), or mastectomy with axillary clearance or sentinel lymph node biopsy. For those who underwent BCS, this has to be followed by external beam radiotherapy to the chest. Premenopausal patients with high grade, large tumour or lymph nodes involvement will be recommended for adjuvant chemotherapy. In some patients with locally advanced tumour, a neoadjuvant chemotherapy is recommended to downsize the tumour, making them more amenable for surgery. Hormonal therapy in form of Tamoxifen is recommended for Estrogen receptor positive patient regardless of the menopausal status. Aromatase inhibitors such as Anastrazole, Letrozole or Exemestane can only be used in ER positive, menopause patient or pre-menopause patient with ovarian ablation (medical or radiotherapy) or oophorectomy. Patients with over-expression of c-erbB2 / Her2/neu have a poorer prognosis but will benefit from immunotherapy using Tratsuzumab or Lapatinib. Threatment for metastatic breast cancer is mainly palliative. This may include systemic chemotherapy, cranial irradiation, hormonal therapy, radiotherapy to the ulcerated lesion or bone metastasis, or the the use biphosphonate