MULTIPLE LIPOMAS
fat cells in the subcu grow into masses that can be moved underneath the skin
the most common benign tumor
lumps range from pea sized to egg or MUCH bigger
familial
dt mitochondrial DNA mutation???
vast majority are painless
mc locations: arms, forearms, legs, trunk
also occurs: neck, face, buttocks
may reach hundreds
most appear during 40's and 50's
lipomas themselves seldom become malignant but lipoma pts have more cancer
INCIDENCE
about 1/3 of cases with large numbers are familial
43% of b9 mesenchymal tumors in Scandinavians were lipomas in one study
solitary more in women
multiple more in men
rare in children and infants
TYPES OF LIPOMAS
(including solitary lipomas, composite from many sources, many overlap)
--adiposis dolorosa (Dercum Disease): multiple painful subcutaneous lipomas, may not be circumscribed, usu on legs, pelvis or trunk, freq assoc with obesity or alcoholism? (this whole sx picture may be incorrect)
--angiolipoleiomyoma: solitary, acquired, asx, acral, incl sm muscle, BVs, CT and fat
--angiolipoma: painful, tender, soft, subcutaneous nodules, frequently multiple, occasionally familial, often present in adolescence, mb multilobulated and firm, vaguely painful w/ pressure or spontaneously
--Bannayan-Riley-Ruvalcaba / Bannayan-Zonana: multiple congenital lipomas, macrocephaly, hemangiomas, mental retardation
--benign symmetric lipomatosis (Madelung disease), men 4x more, head, neck, shoulders, and proximal upper extremities, pt hx often incl excessive alcohol or DM, see Madelung
--chondroid: deep, firm, yellow, on legs of women
--corpus callosum lipoma: rare, congenital, 1-3cm-->larger and sounds like a very bad location
--Cowden syndrome: multiple lipomas, GI hamartomatous polyps, trichilemmomas (sebaceous cysts), incr breast, endometrial and thyroid carcinoma
--Dercum's disease (adiposis dolorosa): rare, lipomas are multiple, large and painful, mc on extremities of obese postmenopausal women, present on upper extremities, mb assoc w/ alcoholism? (A commenter told me this association is bunk and I should remove this factoid), emotional instability?, depression? (also disputed: "Research dating back to 1910 began to cast doubt on psychiatric being a cardinal symptom and modern papers discuss removing it for (sic) diagnosis.)
--diffuse congenital lipomatosis: usu on trunk or large area of extremity, usu occurs before age 2, overgrowth of mature fat, involves muscle and subcutaneous tissue but not nerves, recurrent
--encephalocraniocutaneous lipomatosis (Haberland syndrome): lipomatous hamartomas of the head and face, usu unilateral, congenital, cranial asymmetry and mental retardation
--familial multiple lipomatosis: few to many small encapsulated lipomas usu on extremities, usu appears during or after adolescence, neck and shoulders usu spared (opp: b9 symmetric), autosomal dominant inheritance
--fibrolipomatous hamartoma of nerve/neural fibrolipoma: mature adipose tissue with a fibrous component, infiltrating/surrounding a major nerve mc: median n, loc: epineural and perineural, metaplastic bone has been reported-->macrodactyly, usu under age 30, s/sx assoc with nerve impingment
--hibernoma: brown fat lipoma, usu asx, solitary well-circumscribed nodules, loc: interscapular, axillae, neck, or mediastinum, histol: embryonic brown lipoblasts termed mulberry cells
--intradermal spindle cell lipoma: in women, distrib around body
--lumbosacral lipoma/lipomatosis: diffuse incr in mature fat over lumboscral spine, always occurring with spina bifida or laminar defect, possible meningocele or myelocele, infants and children, may have associated skin tags, hemangioma or hair overgrowth
--Madelung’s Disease (Launois-Bensaude syndrome): multiple subcutaneous lumps AND others that impinge on larynx, esophagus, intestine, lungs, heart, usu not painful, associated with malig tumors of upper airways, hyperuricemia, obesity, renal tubular acidosis, peripheral neuropathy, and liver disease, see b9 symmetric, usu neck, shoulders, upper arms, described as pseudoathletic or horse collar, frequently associated with diabetes and alcohol abuse, mc in men of Mediterranean origin
--MERRF / Ekbom syndrome: myoclonus, epilelpsy and ragged-red fibersm lipomas, skeletal deformities, cerebellar ataxia, photomyoclonus, mtDNA tRNA mutation, multiple endocrine neoplasia type 1: lipomas and pancreatic, parathyroid, pitutitary tumors
--neural fibrolipoma: fibro-fatty tissue along nerve trunk-->nerve compression
--pelvic lipomatosis: usu in black males age 9-80, perivesical and perirectal overgrowth, rarely involves retroperitoneum and mesentery, frequent cystitis glandularis, may develop adenocarcinoma (see proteus synd)
--pleomorphic lipomas: mostly on backs/necks of elderly men, floret giant cells with overlapping nuclei
--Proteus syndrome: congenital pelvic lipomatosis, macrodactyly, exostoses, hemangiomas, linear sebaceous nevi
--solitary lipomas: mc, superficial, small, develops with weight gain but doesn't shrink with weigh loss
--spindle-cell lipoma: asx, slow growing, same loc as pleomorphic
--superficial subcutaneous lipoma: mc type, usu on trunk, thighs, forearms
TREATMENT
excision or liposuction
most will grow back and must be removed repeatedly
tumors may infiltrate muscle and be harder to remove
multilobular harder to remove
PATHOPHYSIOLOGY of SOLITARY
increased levels of lipoprotein lipase
presence of a larger number of precursor cells
~60% of solitary cutaneous lipomas display clonal alterations
mc: breakpoint on bands 12q13-15
also: karyotype aberrations on arms 6p and 13q
SOURCES and RESOURCES
http://surgpathcriteria.stanford.edu/softfat/lipoma/multiple_lipomas.html
Robert V Rouse MD rouse@stanford.edu
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
(This was the source that suggested Dercums was linked to psych sx and alcohol: open question)
http://www.ahealthyme.com/topic/sublipomas
http://en.wikipedia.org/wiki/Lipoma
HOPI WOMAN WITH DERCUM'S
http://azdailysun.com/news/local/article_e54fc832-3e9b-11e0-aed9-001cc4c002e0.html
MEDICAL ADVOCACY GROUP FOR FAT DISORDERS
https://www.fatdisorders.org/
REVIEW OF DERCUM'S DISEASE
https://ojrd.biomedcentral.com/articles/10.1186/1750-1172-7-23
MEDSCAPE ON ADIPOSUS DOLOROSA
https://emedicine.medscape.com/article/1082083-overview
STILL NEED TO HARVEST INFO FROM
http://www.lipomadoc.org/3501.html