Prostate cancer is recognized as the most common cancer affecting North American males, thus imposing a significant health and economic burden. The disease is generally diagnosed in men with advanced ages and is usually treatable when discovered early on. Patients positively diagnosed with prostate cancer are often discovered with low- to intermediate cancer risk and thus immediate treatment generally prevents cancer cells from further dividing. Common treatment modalities for cancer of the prostate include surgery and radiotherapy.
Early Diagnosis of Prostate Cancer
The improvement in medical technologies have facilitated in the early diagnosis and treatment of prostate cancer, especially in terms of monitoring the condition of the patients through time. These patients are monitored through regular follow-ups with their physicians, even after surgery and radiotherapy, in order to determine their rate of improvement. Unfortunately, an estimated 25% of these treated prostate cancer patients have been reported to progress in their disease, with cancer cells continuing to multiply within the prostate gland or having these cancer cells migrating to other parts of the body such as the lymph nodes. These reports thus indicate that there are certain factors that trigger cancer cells to continue proliferation, despite surgery and the administration of chemotherapeutic drugs. It is also possible that the tools employed in estimating cancer risk in prostate cancer patients are not that precise, thus resulting in its recurrence. These reports on cancer recurrence thus suggest the need to identify effective indicators that can help diagnose, monitor, and predict treatment outcomes.
In a recent medical report published in the journal Clinical Cancer Research, the results of a study showed that oxygen levels within a tumor could be employed in predicting prostate cancer recurrence. The investigation was fueled by earlier reports that low oxygen levels or hypoxia in a tumor showed an inverse correlation with the resistance of cancer cells to treatment. In addition, hypoxia levels were also shown to influence cancer risk or the chances of the cancer cells to migrate to other parts of the body. Based on this factor, the clinical scientists led by Dr. Milosevic thus set out to determine the actual effects of hypoxia on prostate cancer patients that have been earlier subjected to radiotherapy.
Using a study population consisting of 247 prostate cancer patients, hypoxia levels were measured before and after radiotherapy. In addition, these patients were monitored for approximately five years to determine the incidence of prostate cancer recurrence based on the proliferation of cancer cells and increase in cancer risk. The study showed that prostate cancer patients with tumor hypoxia before radiotherapy showed greater cancer risk or recurrence after treatment. In fact, 70 out of the 247 prostate cancer patients showed a predictive relationship with hypoxia levels.
Determining Cancer Risk
The use of hypoxia as another marker in determining cancer risk may facilitate in the improvement of diagnostic and prognostic tests for cancer patients. This study may also help in understanding the biology of the prostate gland in relation to development of cancer cells and increasing cancer risk. Investigations on tumor hypoxia are also timely, especially when the use of other prostate indicators such as prostate-specific antigen (PSA) showed highly variable levels in patients. In the last few years, the interpretation of PSA levels in predicting cancer risk has been performed with extreme caution, based on observations that this indicator might not specifically represent the extent of cancer cells or cancer risk among patients.
The development of new technologies in assessing cancer risk may ultimately result in a significant decrease in cancer mortality. Using hypoxia as a predictive tool for cancer risk in various types of malignancies should thus be fully investigated, with the hope of designing treatment schemes that would ultimately prevent cancer cells from further dividing and spreading to the rest of the body.