Fat Tissue Disorders and Lipomas
By Leopoldo M. Cobos, M.D., Yanira Sanchez-De La Torre, M.D., Karen L. Herbst, M.D., Ph.D. Institution: TREAT Program, College of Medicine, University of Arizona, Tucson, Arizona
Many people have a benign (not cancerous) rubbery-feeling roundish mass of fat cells on their body called a lipoma. These fatty benign tumors are found under the skin in the fat tissue layer anywhere on the body, but most commonly on the upper back, shoulders and abdomen.1,2 Lipomas tend to be an inch (~2 cm) or so in size but can grow larger. Single lipomas are usually encapsulated (inside a membrane) and are not painful; these lipomas can be quickly and easily removed with a small surgical incision, so this can be a first easy “operation” for medical students. A different but common lipomatous condition can be found in increased fat on the abdomen, hips and low back where multiple non-encapsulated, pea to marble-sized, mildly firm lipomas form as a result of poor diet, excess food and/or too little exercise. These lipomas are a marker of unhealthy fat and resolve with weight loss, a phenomenon called Ander’s disease.
Genetic conditions involving fat tissue cause nodular fat areas to form making it difficult to lose weight, called persistent fat. This persistent fat can be painful when touched. Persistent fat on the upper body is called Madelung’s disease; when present on the lower body but not the trunk, it is called lipedema and affects mostly women. Painful lipomas, large and small, all over the body is called Dercum disease. In people with hypermobile (very flexible) joints, persistent fat can grow on the abdomen of a thin person. Persistent fat is highly resistant to extreme dieting, exercise, and even bariatric surgery.
People tend to worry when they find a lipoma; however, generally lipomas can be left alone unless there is a reason to suspect cancer, there is a suspicion that the lipoma is one aspect of a genetic disorder, the lipoma grows large enough to be deforming, or it causes significant discomfort or pain. Painful lipomas signal a need to search the remainder of the body fat to look for lipedema or Dercum disease. Fat exams are not taught in medical schools (yet) so by the time patients are diagnosed with a fat disorder they may have suffered with this condition for years. Despite trying a myriad of diets or under-eating and/or over-exercising, they are told by health practitioners “they are just fat” and to “diet and exercise.” This can result in significant psychological distress such as anxiety, depression and eating disorders. Fat disorders can occur in people who are obese and people who are non-obese, and usually in more women than men.
If a lipoma is to be treated, it is usually by surgical excision, which can be done as an outpatient office procedure, although deeper or larger lipomas, lipomas near crucial body structures, or multiple lipomas may require general anesthesia and experts such as hand, oncological and neurological surgeons. Once lipomas are removed, they tend not to recur, though other lipomas and fat can move into the evacuated area. Indications for removal typically include cosmetic concern, inhibition of mobility of a body part or significant pain.
Fat disorders require a different treatment approach when compared to conventional lipomas.
Although most lipomas tend to occur during the ages of 40-60 years and are more common in men3, persistent fat disorders can occur at younger ages and more commonly in women.
Dercum disease, a rare disorder also known as adiposis dolorosa (meaning painful fat), which occurs primarily in women and on average manifests at age 35 years4 and is characterized by the development of painful lipomas which tend to appear in the arms, legs, chest, back and abdomen, generally sparing the head, hands and feet. About 75% of people with Dercum disease tend to be obese (but 25% are not) and usually have other symptoms such as fatigue, gastrointestinal symptoms, muscle aches, joint pain and brain fog in addition to issues with emotions, memory and depression. Patients with Dercum disease usually suffer with symptoms for some time before receiving a diagnosis of Dercum disease, and many are diagnosed with fibromyalgia. Adequate palpation of lipomas or small fatty nodules the size of a pearl in non-obese and obese people can be difficult due to the body habitus. Ultrasound is the best imaging modality to find lipomas, but lipomas can also be seen by magnetic resonance imaging (MRI) that uses magnets for imaging (no radiation).7
Women and men with Dercum disease can feel isolated and disbelieved due to being told by healthcare providers that their lipomas should not be painful; after diagnosis, there is an emotional release in the majority of cases. Things that worsen lipoma pain in Dercum disease include stress, overactivity and extreme temperatures.
If you notice multiple painful lipomas on your body, a dermatologist along with other physicians can determine if you have Dercum disease.
Lipedema, from “lipos” meaning fat and “oedema” meaning fluid, is as its origin states, increased fluid in fatty tissue. Lipedema is a disorder of abnormal fat distribution that is characteristically found in women, and rarely in men with hypogonadism (low testosterone and relatively higher estrogen).6 Women with lipedema have different types of increased symmetrical fat deposition from the ankles or knees up to the waist; the trunk is spared producing a dramatic small waist and depositions of fat on hips/thighs/buttock, sparing the hands and feet (this is different from LYMPHedema that causes fluid to pool on the hands and/or feet). The fat can cover the lower legs in a stovepipe configuration where the tissue balloons out in a cuff at the ankle (Figure). Breasts can be any size. Arms can be less affected but have abnormal tissue in 80% of cases. Lipedema is also classified in stages, depending on the severity of the disease (Figure); Stage 1 being the earliest manifestation and Stage 3 being a late manifestation of the disease. LYMPHedema (fluid in the tissue from damage to the lymphatic system) can occur with any stage but especially Stage 3. Lipedema usually develops during periods of hormonal imbalance such as during menarche (1st menstrual cycle), after pregnancy, and during menopause; hence it is thought to be influenced by changes in female hormones (estrogen/progesterone).
One interesting and important fact seen on examination of patients with lipedema is that they tend to be “metabolically healthy,” meaning that although they tend to be classified as “obese,” they do not have the conditions often associated with overeating such as diabetes, insulin resistance, high blood pressure, and increased cholesterol5 despite the fact that the fat has inflammatory cells similar to obesity. Women with lipedema are frequently misdiagnosed as simply obese and are frustrated in not being able to lose fat with diets and/or extreme exercise routines. Obesity can, however, occur along with lipedema causing dramatic growths in heavy fluid-filled fat tissue with accentuation of the lower body shape that impedes walking, which in turn promotes more obesity.
Maintaining weight with diet and exercise is key in lipedema to keep fat growth low to reduce the burden of excess fluid on the lymphatic system, the drainage "pipes" of fat tissue. An overflow of fluid from the smallest blood vessels in the body (venules and capillaries) into fat tissue is thought to be one important factor in the development of lipedema. Producing too much fluid and its contents in fat can result in fluid buildup around fat cells, blood vessels, nerves, muscles and other structures, and blood vessels as well as lymphatics begin to function poorly and leak. Growth factors, cell growth and waste products, fatty acids and cholesterol, and other nutrients, especially sugar, cause more fat to grow. If the amount of fluid produced overwhelms the fluid pumped out by the lymphatic system, the fluid stays in the tissue causing it to swell. Early on this swelling typically resolves during sleep but eventually the swelling does not resolve because the lymphatic system has become damaged.
Worsening of lipedema contributes to a constant inflammatory state which can be seen on blood tests such as one called C-reactive protein, a lab test that measures the signal from the liver to repair areas of inflammation. The clotting system is also involved and many times a marker of the complement system is elevated, called CH50.
If a woman has or develops vein problems such as varicose veins or chronic venous insufficiency, this in turn can worsen lipedema and lymphedema and make it harder to treat. It is important to point out that lipedema can cause LYMPHedema, but LYMPHedema can also be seen in patients who have an injury to lymphatics, commonly in women who have multiple lymph nodes removed during surgery for breast or uterine cancer or who have had radiation to lymph node areas.
Women with lipedema can also have significant psychological distress due to their inability to lose weight. Acceptance of persistent fat in the academic setting and in the community is now enabling more research into this area.
WHEN TO CONSIDER BEING EVALUATED FOR FAT TISSUE DISORDER?
Fat tissue disorders should be taken into consideration if you develop significant fat deposition after a major hormonal change in life such as puberty, pregnancy or menopause and the fat has not reduced compared to reduction of fat on the trunk despite strict diet and exercise, or if you have multiple lipomas or any painful fat. If you have been told you are obese and have improved your diet and exercise routine for at least 6 months without improvement, then evaluation for a fat disorder should be considered. If you have lumpy or painful fat, you may have lipedema or Dercum disease. You may also have lipedema if you became “hippy” or develop “thunder thighs” or “cankles” around puberty.
WHAT TREATMENT IS AVAILABLE FOR LIPEDEMA/DERCUM DISEASE?
Standard treatments include manual (hands-on) therapies such as manual lymphatic drainage by trained physical or occupational therapists and licensed massage practitioners, compression garments to manage fluid in the tissue, specialized garments connected to a pump that mimics manual lymphatic drainage and maintaining healthy eating and exercise to prevent obesity. Deep fat tissue therapy, manual or by a machine, can be painful but it changes the structure of the tissue allowing better blood flow in and lymphatic flow out of the fat tissue. Other therapies can include the use of tools to reduce fibrosis and improve flow and function of tissue such as gua sha, Astym, Sastm or Graston. Patients with lipedema have found benefit after liposuction through surgeons who specialize in treating fat disorders. There are supplements and medications that can help decrease inflammation and improve lymphatic flow. We recommend to first talk to your healthcare provider before trying anything new. There is active research to find genes associated with lipedema and Dercum disease and several other therapies are currently undergoing trials. Further research and attention needs to be placed on fat disorders, although Dercum disease appears to be rare, lipedema likely affects millions of women worldwide, yet is frequently undiagnosed. Women need to be empowered to find out if they have a fat disorder. Joining a support group can help as well as finding counselors, and healthcare providers to help you live healthy productive lives without stigma. We hope this article helps in that empowerment.
Resources on fat disorders
About Dr Herbst:
Karen L. Herbst PhD, MD is a board-certified endocrinologist, Associate Professor and Director of the Treatment, Research, Education of Adipose Tissue (TREAT) program in the College of Medicine at the University of Arizona and Banner University Medical Center, Tucson, funded by the Lipedema Foundation. Dr. Herbst has been working in the area of fat disorders since 2003, and currently has a clinic dedicated to patients with these disorders. In her clinic she is training future pharmacy students and residents, medical residents and endocrinology fellows to recognize and treat fat disorders. She is a founding and current member of the not-for-profit Fat Disorders Resource Society which is dedicated to education, awareness and promotion of research for fat disorders.
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