Can anemia at diagnosis predict the course of the treatment and survival in patients with rectal cancer?

This study investigated the association between hemoglobin or Hb (a protein found in the blood that carries oxygen to the tissues of the body) levels at the time of cancer diagnosis, response to treatment and long-term outcomes in patients with rectal cancer.

Rectal cancer is caused by an uncontrolled cell growth in tissues of the rectum (the lowest part of the large bowel). Some rectal cancers can be more difficult to remove with surgery alone. These patients often need additional treatments such as chemotherapy and/or radiotherapy. Additional treatment before surgery to remove the cancer is called neoadjuvant therapy. Patients with rectal cancer often have blood loss in the stool. This leads to anemia, which is a defined by a low number of red blood cells or Hb in the blood. Anemia makes the patient feel tired, weaker or dizzy because the organs of the body do not get enough oxygen. Treatment for rectal cancer can also cause anemia, adding to the patients’ condition. Previous studies have found that anemia can also influence the prognosis in patients with rectal cancer. The aim of this study was to evaluate whether Hb levels before treatment for rectal cancer was associated with stage of the cancer, response to treatment, cancer recurrence (return of the cancer) or survival. 

This analysis included 463 patients with rectal cancer. Hb levels were measured before treatment for all patients included in the study. Patients were treated with either radiotherapy alone or together with chemotherapy before surgery to remove the cancer. Results showed that patients with Hb levels of less than 12g/dl showed less response to neoadjuvant treatment. In contrast, there was a strong association between Hb levels of above 12g/dl and a complete response to treatment. Also, cancer recurrence was more common in patients with Hb levels of less than 12g/dl over a follow up period of 2 years. However, there was no relationship between Hb levels and metastases (cancer that has spread to distant organs or tissues) or survival. The authors of the study also found that lower Hb levels were associated with larger cancers. 

In summary, Hb levels before beginning treatment predicted the size of the cancer, the response to treatment and risk of recurrence in patients with rectal cancer.

A possible drawback for this study could be that the authors did not accurately determine the size of the cancer. This depended on the experience of the doctor. 

Visit your doctor for regular check-up on Hb levels.