Possible forms of cancer associated with unexplained weight loss are stomach, pancreas, or liver cancer (affects digestion and metabolism), lung or esophageal cancer (which interferes with swallowing and appetite), and blood cancers such as leukemia and lymphoma (which affect metabolism and immune function).
Constant fatigue and weakness
Unlike fatigue that is a result of lack of sleep and tiredness, fatigue that may indicate some more serious conditions, including cancer, is persistent.
