Complete decongestive therapy (CDT; alternatively known as complete decongestive physiotherapy) is a treatment program for patients diagnosed with primary or secondary lymphedema. CDT incorporates manual lymphatic drainage (MLD), a technique involving therapeutic manipulation of the affected limb. There are several contraindications to performing CDT. Relative contraindications include hypertension, paralysis, diabetes, and bronchial asthma. General contraindications include acute infections of any kind and congestive heart failure. Malignant disease is also widely considered a general contraindication; a current vogue concept is that MLD will lead to dissemination and acceleration of cancer. However, cancer research supports the contention that this therapy does not contribute to spread of disease and should not be withheld from patients with metastasis. The intent of this article is to review these data.