Man presents with weight loss, fatigue, nausea

A 42-year-old man presented to the emergency department with complaints of difficulty ambulating, fatigue, unintentional weight loss and progressively worsening near vision.
His medical history was notable only for Bell’s palsy. He denied any surgical history and reported no current medication use. A self-reported allergy to acetaminophen was documented. Social history was significant for occasional cigarette and cannabis use, but he denied alcohol consumption. There was no contributory family history to report.
The patient reported an approximate 60-pound unintentional weight loss over the