Question: In a patient with confirmed cancer, our oncologist documented fatigue. How can we report this symptom in a cancer patient? Is this same as asthenia? Alabama Subscriber Answer: You have a specific code for fatigue related to neoplastic conditions. For fatigue in cancer patients, you submit ICD-10-CM code R53.0 (Neoplastic [malignant] related fatigue). Remember! Always check for the cause of fatigue and confirm it to be cancer related before you submit code R53.0. Fatigue and asthenia are not the same. When you find documentation of asthenia, you submit code R53.1 (Weakness).