Cancer, Hodgkins disease (adult): A type of lymphoma (cancer of the lymphatic system). The most common symptom of Hodgkins disease is a painless swelling in the lymph nodes in the neck, underarm, or groin. Hodgkins disease is diagnosed when abnormal tissue is detected by a pathologist after a biopsy of an enlarged lymph node. Treatment usually includes radiation therapy or chemotherapy. Regular follow-up examinations are important after treatment for Hodgkins disease. Patients treated for Hodgkins disease have an increased risk of developing other types of cancer later in life, especially leukemia.