An 80 year old man with a past medical history significant for depression presents with fatigue. About 5 months ago, his wife passed away from colon cancer, and since then, he has had a dramatic change in diet. He doesn't cook for himself and eats mainly fast food. He has also started drinking more alcohol. His exam, including neurologic and psychiatric exam, is completely normal. Labs show anemia, elevated serum bilirubin, elevated LDH, and a low-to-normal absolute reticulocyte count. WBC and platelets are low. The blood smear is shown below.
Challenge: What's the most likely diagnosis? Second most likely diagnosis?
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