Breast cancer is a major killer world wide. In USA it is the most common non-skin cancer and the second leading cause of cancer-related deaths in women. Approximately 500,000 deaths worldwide are related directly or indirectly to breast cancer. Presently mammography is used extensively for breast screening and is effective in picking up breast cancer at an earlier stage, thus, decreasing the mortality rates from breast cancer. While mammography is highly effective in detecting breast cancer, it is not foolproof. With the advent of MRI, instead of using mammography, some patients are requesting MRI to screen for breast cancer. Is this wise?

While MRI has a high sensitivity in detecting breast abnormality, it has a low specificity. In other words, MRI can over diagnose and give you more reading of ‘cancer’ when the actual abnormal appearance on the scan is not due to cancer. In high-risk groups, such as women with breast cancer gene (BRCA) mutations, MRI is likely to be more sensitive than mammography, ultrasound and clinical breast examination in detecting breast cancer earlier. The reasons for this are that BRCA1-associated breast cancers are more likely to have round, pushing margins and rare calcifications and other benign mammographic appearances. Childhood cancer survivors are another group of high-risk individuals who might benefit from MRI because these individuals have dense breast tissue which makes mammographic assessment more difficult. It is a challenge for doctors to detect early breast cancer in breasts augmented with silicone because cancerous changes may be misinterpreted as silicone-induced mastopathy. MRI is good for differentiating between cancerous changes and silicone induced nodularity.

In patients with axillary lymphadenopathy (swollen lymph glands in the armpit) due to an occult breast cancer (non-palpable and non-mammographically visible), MRI can help to detect a suspicious breast lesion. Sixty percent of patients with ductal carcinoma in situ (DCIS) may develop invasive breast cancer over a period of 10 years. In a German study involving 7000 women who were subjected to mammography and MRI over a 5-year period, MRI detected significantly more cases (92%) of any grade of DCIS than mammography (56%). The study found that MRI is better in diagnosing DCIS, especially those with high-grade DCIS (Lancet 2007; 370: 485 – 492). However, it must be emphasized that the role of MRI in DCIS is not fully established.

At the recent 92^nd Clinical Congress of the American College of Surgeons, it was stated that breast MRI is an essential tool in screening high-risk groups, assessing the extent of disease and follow-up. MRI also has a role in cases of unknown primary tumour and in assessing the response to chemotherapy. The American Cancer Society recommends a screening MRI for women who have 20 – 25% or greater lifetime risk of breast cancer, including those with a strong family history of breast or ovarian cancer and those treated for Hodgkin’s disease (CA Cancer J Clin 2007; 57: 75 – 89).

Like all high tech medical tools, MRI of the breast is not applicable to everyone. It has limitations and requires clear guidelines as to when it should be used. When used judiciously, MRI is invaluable in guiding the doctors in managing a case of breast cancer. When used inappropriately, MRI can over-diagnose breast cancer in someone without breast cancer, giving rise to unnecessary anxiety and worse still causing someone to undergo an unnecessary and potentially disfiguring operation. 

(For those interested in reading a recent review article on the role of MRI in screening, diagnosis and management of breast cancer, please consult Expert Rev Anticancer Ther 2008; 8: 811 – 817)

Hepatocellular carcinoma (HCC or primary liver cancer) is common in Asia because of the high incidence of hepatitis B virus (HBV) chronic infection in the population. However, in some countries such as Japan and southern part of Taiwan, hepatitis C virus (HCV) infection has become more prominent than HBV as a causative agent for HCC. Chronic HBV and HCV infection can lead to cirrhosis (hardening of the liver) and HCC. HBV carriers have a 100-fold increased risk of HCC relative to those without HBV infection. About 2.1% of HBV carriers develop cirrhosis each year. The annual incidence of HCC in patients with cirrhosis is 3 – 10% (J Gastroenterol Hepatol 2000; 15 Suppl: E25 – E30). Immunisation will help prevent HBV but not HCV infection. Its effectiveness in reducing the incidence of HCC has been well proven in Taiwanese children. In 1984, a mass neonatal vaccination programme against HBV was launched in Taiwan in order to control the incidence of perinatal HBV infection. The HBV carrier rate decreased from the historical 15 – 20% to < 1% after vaccination and the annual incidence of childhood HCC has decreased from 0.67 to 0.19 / 100,000 children (Hepatol Res 2007; 37 Suppl 2: S101 – S105). What happens if you are already an HBV / HCV carrier and you happen to be obese and/or suffer from diabetes? Is your risk of HCC lower or higher?

A recent study from the National Taiwan University followed 23,820 Taiwanese residents for 14 years to see if obesity, diabetes and other metabolic factors were independently associated with HCC (Gastroenterology 2008; 135: 111 – 121). The HBV and HCV status of all these residents were determined at enrollment. Extreme obesity (BMI ≥ 30 kg / m2) was independently associated with a 4 – fold increased risk of HCC in those with HCV infection but not in HBV infected individuals. If you are neither HBV nor HCV infected but you are extremely obese, you have a 2-fold increased risk of developing HCC. If you are HCV infected and suffer from diabetes, your risk of developing HCC is increased by 3.52 times. In the case of HBV, the risk is increased by 2.27 times. If you are both obese and diabetic, the risk is increased > 100 fold for both HBV and HCV carriers. This finding implies synergistic effects of metabolic factors and hepatitis infection.

Obese individuals have a higher risk of developing diabetes mellitus. If you are an HBV / HCV carrier, you have a very strong incentive not to get overweight and increase the risk of developing diabetes mellitus. At present, we are not able to cure a significant number of HBV or HCV carriers with medication; thus, it is important for all carriers to reduce their risk of developing HCC on top of their hepatitis infection. Staying trim and healthy will certainly help!

Most people would associate chronic kidney disease (CKD) with kidney failure requiring dialysis or kidney transplantation. However, CKD is not just about kidney failure. There are 5 stages of CKD, namely, stage 1 – glomerular filtration rate (GFR) ≥ 90 ml/min/1.73 m2 with proteinuria (protein in the urine), stage 2 – GFR 60 – 89 ml/min/1.73 m2 with proteinuria, stage 3 – GFR 30 – 59 ml/min/1.73 m2, stage 4 – GFR 15 – 29 ml/min/1.73 m2 and stage 5 – GFR < 15 ml/min/1.73 m2. Patients with stage 4 or 5 CKD are having end stage kidney disease. Most patients with CKD would have died from other causes before they reached the dialysis state. While there are ample information on the prevalence of end-stage renal disease in the general population, information on national prevalence of CKD is not widely available.

A recent study from the National Health Research Institutes of Taiwan looked at the prevalence of CKD in a cohort of 462, 293 individuals older than 20 years who participated in a standard medical screening programme since 1994 (Lancet 2008; 371: 2173 – 2182). They were observed for 13 years with a median follow-up of 7.5 years. CKD in this cohort was determined by GFR (estimated from a formula based on serum creatinine) and urinary protein. From this cohort of participants, the national prevalence of CKD was determined. The national prevalence of CKD in Taiwan was 11.93%. The prevalence of CKD differs according to the socioeconomic status of the individual. In the low socioeconomic status population, the prevalence of CKD was 19.87% as compared to 7.33% in the high status group. Cohort participants with CKD had an 83% higher risk of dying from all causes of death compared to those without CKD. The risk of dying from cardiovascular diseases was 100% higher for those with CKD. In the whole study population, 10.3% of deaths were attributable to CKD but in the low socioeconomic status population, 17.5% of deaths were attributable to CKD. Thirty nine percent of people with CKD who died did so before the age of 65. Another interesting fact that came out of this study was that regular users of Chinese herbal medicines had a 20% increased risk of developing CKD.

People with stage 1 to stage 3 CKD are usually asymptomatic. Unless you measure the GFR (either by actual measurement or from estimation with a formula based on serum creatinine), you will not know there is a problem with your kidneys. Unless you test your urine for protein, you will not know you have proteinuria. Testing urine for the presence of protein is not a laborious or difficult task. All it involves is dipping a test strip into some urine and comparing the colour changes on the strip against a chart. The test strip will not only tell you whether you have protein in the urine but also if you have blood, white cells and bacteria in the urine.

The use of Chinese herbal medicines by the Chinese population is unavoidable. However one should be mindful that injudicious use can damage your internal organs such as the kidneys or the liver. If CKD does not kill you immediately, it will certainly increase your risk of dying from other causes at a relatively young age of below 65.

For those who could not afford a full medical health check, just having a simple urine dip stick test can give your doctor very valuable information on the status of your kidneys. The good thing about urine dip stick is – its very cheap!