Lymphoma is a form of cancer that originates in the lymphocytes, a type of white blood cell, and involves the lymphatic system. Changes in body weight are a common occurrence for many patients. While weight loss is often the symptom most associated with advanced cancer, weight gain is also a recognized phenomenon in the context of lymphoma. Understanding the specific relationship between lymphoma and weight gain requires looking beyond the disease itself to examine the powerful effects of the treatments used to manage the condition.
Weight Gain Versus Weight Loss in Lymphoma Patients
Unintended weight loss is a classic symptom of many cancers, including lymphoma, often categorized as a “B-symptom” when it involves losing more than 10% of body weight within six months. This loss results from a hypermetabolic state where cancer cells consume significant energy, and the body’s inflammatory response breaks down fat and muscle. In contrast to this pre-diagnosis weight loss, weight gain is a common experience for many individuals during and after lymphoma treatment.
Studies focusing on non-Hodgkin lymphoma patients have observed that a significant portion of individuals gain weight following diagnosis or treatment. This shift from a catabolic (breaking down) state to an anabolic (building up) state often reflects a positive response to treatment, which reduces the cancer’s metabolic drain and may restore appetite. Weight gain is frequently linked to the side effects of therapy rather than the disease itself.
Treatment-Induced Weight Changes
The primary driver of weight gain for lymphoma patients is the use of corticosteroids, such as prednisone or dexamethasone, routinely included in chemotherapy regimens. These steroids serve multiple purposes, including destroying lymphoma cells, reducing inflammation, and preventing nausea and allergic reactions related to chemotherapy. The physiological effects of these drugs, even when taken for only a few days during each cycle, directly promote weight gain.
Corticosteroids dramatically increase appetite, leading patients to consume more calories. Simultaneously, these medications influence metabolism and cause the body to retain salt and water, known as fluid retention or edema. This fluid accumulation can manifest as swelling, especially in the ankles and feet, and contributes directly to the number seen on the scale.
Steroid use can lead to fat redistribution, causing an increase in abdominal fat and a puffy appearance in the face, sometimes termed “moon face.” These medications also disrupt blood sugar balance, potentially leading to high glucose levels that encourage fat storage. Reduced physical activity due to chemotherapy fatigue is another contributing factor, as lower energy expenditure combined with increased appetite creates a calorie surplus.
Physiological Mechanisms Independent of Treatment
While treatment is the most common cause of weight gain, the lymphoma itself can cause an increase in measured weight through mechanisms unrelated to steroid use. This weight gain is often not due to fat or muscle tissue but is instead a reflection of abnormal fluid accumulation. This condition, known as edema, occurs when fluid builds up in the body’s tissues.
Lymphoma is a cancer of the lymphatic system, and a growing tumor can physically block lymph vessels or press on major blood vessels, impairing the body’s ability to drain fluid effectively. When this obstruction occurs, fluid can collect in the limbs, causing swelling, or in the abdomen, leading to ascites. Ascites is an abnormal buildup of fluid in the peritoneal cavity, which causes significant abdominal distention and an increase in total body weight.
In rare instances, lymphoma can affect or produce substances that interfere with endocrine organs, potentially shifting the body’s metabolism to favor fat storage. For example, some long-term survivors of lymphoma treatment may develop thyroid dysfunction, such as hypothyroidism, which can slow metabolism and contribute to weight gain. These physiological changes contribute to the complexity of weight fluctuations observed in patients.
Monitoring Weight and Communicating with the Care Team
Consistent monitoring of body weight is an important step for any patient undergoing lymphoma treatment. Patients should weigh themselves regularly and note any rapid or significant changes, reporting them to the oncology team. A sudden weight gain of three pounds or more within a week could signal excessive fluid retention, which requires prompt medical attention.
Managing treatment-related weight gain often involves focusing on the quality of nutrition and maintaining gentle activity levels, provided the care team approves. Working with a registered dietitian can help create a balanced eating plan that accounts for increased appetite without resorting to high-calorie, low-nutrient foods. For fluid retention, the care team may offer specific advice on managing hydration and potentially using diuretics to control swelling. It is important not to attempt to lose weight without first consulting the care team, as maintaining adequate nutrition and strength is paramount during therapy.