Recently, the wife of a patient with a pancreatic cancer asked “Why were there no symptoms?” A good question and very often asked by many. The pancreas is an organ that sits right at the back of your abdomen. It is very deep and therefore is very difficult to feel on examination. Ultrasound scan of the upper abdomen, though frequently done for health screening, can find it difficult to visualise the entire pancreas because the air in the over-lying intestine obscures the view of the pancreas. When you do develop symptoms such as jaundice or intractable back pain, the pancreatic cancer is usually quite large or advanced. Hence many patients with pancreatic cancer would have inoperable cancer when they first present to the doctor or surgeon. However, there will be a group of patients who, at presentation, will have a borderline resectable pancreatic cancer. In most instances they would be offered chemotherapy or symptomatic treatment only. But should that be the case?

Researchers from the Texas MD Anderson Cancer Center reported their experience with treating patients with borderline resectable pancreatic cancer (J Am Coll Surg 2008 206: 833 - 846). These patients were: patients with tumour abutting on the visceral arteries or short-segment occlusion of the superior mesenteric vein, patients with findings suggestive but not diagnostic of metastasis and patients with marginal performance status. All these patients were treated initially with chemotherapy, chemoradiation or both and then reassessed for surgery. Between October 1999 and August 2006, they had 160 patients with borderline resectable pancreatic cancer. One hundred and twenty patients completed therapy and were restaged. Of these 125 patients, 66 (41% of the original 160 patients) underwent surgery to remove the pancreatic cancer. The study showed that the median survival for these 66 patients was 40 months. For the 94 patients who had chemotherapy / chemoradiation but did not have surgery to remove the pancreatic cancer, the median survival was only 13 months.

While many pancreatic cancers at diagnosis are clearly not operable, there are some patients who are clearly operable and some who are borderline operable. Operability or borderline operability can only be decided upon by a pancreatic surgeon. Once the surgeon has determined that it is borderline operability, the medical oncologist and surgeon will need to work closely together so that a proportion of patients will be able to undergo surgery to remove the pancreatic cancer, thus giving these patients a chance to survive much longer.

It’s that time of the year again. Around this time, the annual haze from Kalimantan and Sumatra drifts over Singapore and gives it a hazy blanket. This annual air pollution is due to the clearing of forest by burning so that citizens living on the two islands can use the land to plant crops for the next season. This annual event has been taking place for more than 10 years now. Apart from the occasional cough, sore throat, itchy eyes and hazy sunshine, most people just view the haze as a ‘normal’ occurrence and a necessary evil for living in Singapore.

Air pollution is essentially a complex mixture of gaseous compounds (ozone, carbon monoxide, nitrogen dioxide) and particulate matter (PM). The PM is a heterogenous mixture of solids and liquids varying in chemical constituents (organic and elemental carbon, nitrates, sulphates and metals) and sizes (from a few nanometers to 10 μm in aerodynamic diameter). In the modern urban world, fossil fuel combustion (as used in automobiles and industry) is the major source of anthropogenic (manmade) pollution. In Singapore, there is an additional seasonal anthropogenic pollution – the haze. The PM in haze is typically < 10 μm in diameter.

A recent study from the Harvard School of Public Health looked at whether particulate air pollution exposure is related to venous thrombosis (Arch Intern Med 2008; 168: 920 – 927). The researchers examined the association of exposure to PM of < 10 μm in aerodynamic diameter (PM10) with deep vein thrombosis (DVT) risk in 870 patients and 1210 controls from the Lombardy region in Italy. (DVT is the formation of clots in the deep veins of the calf. It is also called the economy class syndrome.) The study found that a higher mean PM10 level in the preceding year was associated with a shortened prothrombin time (PT) in the DVT cases. (PT is a measure of how well the blood clots. The shorter the PT, the quicker the blood clots.) Every increase of 10 μg/m3 in PM10 was associated with a 70% increase in DVT risk. Thus, particulate air pollution is associated with altered coagulation function and DVT risk.

Researchers from Edinburgh University exposed 20 men with prior myocardial infarction (heart attack) to dilute diesel exhaust or filtered air for 1 hour during periods of rest and moderate exercise in a controlled-exposure facility (N Engl J Med 2007; 357: 1147 – 1149). During both exposure sessions, ST-segment depression (an indication of myocardial ischaemia) was present but the depression was greater (meaning greater extent of oxygen deprivation to the heart muscles) during the period of diesel exhaust exposure. Furthermore, the acute release of endothelial tissue plasminogen activator (a mechanism for dissolving any clots in the blood vessels) was also reduced by diesel exhaust exposure.

With the oil price now at US$125 per barrel, it might not be a bad time to think about reducing ‘car power’ and increasing ‘foot power’. This will not only save on fuel cost but also save on pollution induced health costs.