One of the weirdest aspects of cancer diagnoses is that there’s no consistency in symptoms. For example, some people may experience weight loss and malnutrition through an inability to eat. However, others may have the opposite problem as they gain weight for several reasons.
Water retention is one of the main causes of weight gain but constipation can also be a factor. The brain fails to send messages to the digestion symptom and causes problems with passing waste. It’s very uncomfortable and can also be emotionally challenging for the patient to deal with. (via Maggies.org)