Should we Treat the Anemia of Retinopathy and Cancer?
Anemia is a deficiency of red blood cells in the body. The Red Blood Cells (RBCs) carry oxygen throughout the body. Symptoms of anemia are, most notably, fatigue. Other symptoms are feelings of discomfort or uneasiness, shortness of breath, palpitations of the heart and lack of concentration. Nails may become flat or concave and skin pallor may be present. Anemia prevalence depends on many factors in cancer, but runs as high as 80-100% in patients treated with chemotherapy.
Retinopathy is an inflammatory condition affected frequently by circulatory problems. New blood vessels may grow on the surface of the eye. These blood vessels may cause vision to be spotty or blurry. This type of retinopathy is called “proliferative”.
Having anemia or retinopathy decreases quality of life but treatments are available. However, do we want to treat anemia of cancer and proliferative retinopathy? A recent study published by Dr. L.Smith in the February issue of the Journal of Clinical Investigation indicates that treatment of anemia with erythropoietin, a hormone known to stimulate red blood cell production, which in turn, helps the anemia, may cause more harm than good. The findings by Lois Smith, MD, PhD, an ophthalmologist, concluded that the administration of erythropoietin may cause abnormal blood-vessel growth, thus complicating the treatment of anemia caused by cancer and retinopathy in mice.
Given at the wrong time, erythropoietin may make blood vessels grow and develop in the wrong manner. So, you might cure the anemia, but worsen the retinopathy. Erythropoietin when injected into mice, for example, caused numerous blood vessels to develop, but because the vessels were deformed, the retina was pulled to the back of the eye and the mice went blind. However, timing of the administration of erythropoietin introduced a study variable. When administered early, the disease process was slowed down. Administered later in the treatment the mice went blind.
This creates a dilemma in treating anemia. Now the question can be raised as to whether treating anemic conditions of abnormal cellular grown, such as cancer and retinopathy, with erythropoietin may yield anemic patients a worse fate. Will it make the tumors grow faster? Will it increase the rates of blindness? Clearly more research is needed with human subjects. Such treatment should now be followed to determine if abnormal cellular trends escalate with the erythropoietin treatments in human anemic patients.
Bottom line: This study does not yield enough evidence to say “stop treatments of the anemias of cancer and retinopathy with erythropoietin”, but watch the literature, follow those patients more closely on a case study basis, conduct more studies in humans and introduce this study as a thought provoking variable when looking for evidence based research to back your treatment of anemia in these conditions.
About the Author
Kathy Shattler received her Master of Science degree from Michigan State University in E. Lansing Michigan in Human Nutrition. Her twenty-two years of practice includes holding positions as a Lecturer, Chief Clinical Dietitian and Program Manager. Kathy is the Founder of Nutri-Care Consulting and is currently the Nutrition Director of www.CEU4U.COM, an online continuing education management company for Registered Dietitians and Dietetic Technicians.
