A complete blood count is one of the most fundamental preventive exams, and its results might raise the possibility of a variety of health problems, including cancer. Hemoglobin (Hb) is one of the most crucial metrics to pay close attention to.
Low hemoglobin and cancer
Low levels of hemoglobin (Hb), the oxygen-carrying protein present in red blood cells, are a sign of anemia. Anemia is a typical symptom of cancer development in the body and can occur as a side effect of cancer treatment. It is estimated that more than 40% of patients will experience it.
Of course, there are many other possible reasons for anemia (such as a poor diet or pregnancy), so additional diagnosis is required if blood test results are unsatisfactory. Adult men should have hemoglobin levels above 14 g/dl, while women should have levels above 12 g/dl.
What cancers can low hemoglobin indicate?
Low hemoglobin, indicative of anemia, is most common in cancers such as:
- colorectal cancer ,
- cervical cancer ,
- stomach cancer ,
- lung cancer ,
- kidney cancer ,
- ovarian cancer ,
- prostate cancer,
- melanoma ,
- leukemias ,
- lymphomas .
It is believed that, in fact, all types of cancer can cause anemia. However, some increase this risk.
Anemia associated with cancer may result from various causes, such as:
- bleeding (e.g. cancer in the reproductive tract, digestive or respiratory system),
- iron, folic acid or vitamin B 12 deficiency , but also protein or vitamin B 6 deficiency – e.g. due to malabsorption or nutritional disorders,
- bone marrow damage during oncological treatment,
- bone marrow infiltration or metastases,
- hemolysis , i.e. the passage of hemoglobin into the blood plasma caused by damage to the erythrocytes (e.g. in lymphoma),
- impaired erythropoiesis , i.e. the formation and multiplication of red blood cells (in various cancers)
Low hemoglobin and cancer. What does the MCV tell us?
Low hemoglobin indicates anemia, and the red blood cell volume (MCV) is an important parameter that can help identify the source of the condition. Microcytosis is typical of iron deficiency anemia, while macrocytosis occurs when there is a lack of folic acid or vitamin B12. Normally sized blood cells are found in chronic diseases.
Low iron levels and cancer
Iron deficiency is the most common cause of anemia, accounting for 80% of all cases. A study published in PLOS ONE suggests that people with iron deficiency anemia have a higher risk of developing cancer, particularly pancreatic, kidney, liver and bladder cancer. Low iron levels can also indicate the presence of cancer. Bleeding can occur from the gastrointestinal tract, reproductive tract, kidneys and lungs.
What cancers cause low iron levels?
Low iron levels can indicate the development of cancers such as:
- gastrointestinal cancers (e.g. colon cancer, stomach cancer, esophageal cancer),
- pancreatic cancer,
- cancers of the genitourinary system (e.g. cervical cancer),
- respiratory cancer (e.g. lung cancer),
- blood cancers.
Oncological treatment may also contribute to iron deficiency, which is often the result of a weakened appetite or damage to the gastrointestinal mucosa.
Anemia and cancer : What tests to do?
To begin, stool tests are performed numerous times to check for the presence of occult blood (which cannot be seen) and endoscopic examinations, which show the anatomy of nearly the whole digestive tract from the inside (except for the small intestine, which fortunately is rarely the site of tumor development).
Urinalysis to detect the presence of red blood cells in the urine is recommended, and a gynecological examination is also recommended in women. Only after diagnosing the cause can suitable treatment, such as iron preparations, be implemented.