Lipoma/painless palpable mass/soft-tissue tumor

ipoma is the most common soft-tissue tumor. It is composed of adipose (fat) cells and enclosed by a thin, fibrous capsule. Lipomas can originate in any part of the body where normal fat is present, and microscopically, it is impossible to distinguish these benign masses from the normal adipose tissue. Most commonly, lipomas occur in the upper part of the body, specifically under patients' skin on the head, neck, shoulders, arms, and backs. Occasionally they may present in a deep location or originate within a muscle or an organ. They may be solitary or multiple.Lipomas can occur at any age. However, they are commonly found in adults aged 40–60 yearsand are more prevalent in men than in women. Most lipomas are small ovoid tumors weighing only a few grams and measuring less than 5 cm. They typically present as a localized subcutaneous soft mass that causes cosmetic concerns for the patient. Lipomas are generally asymptomatic unless they encroach joints, blood vessels, or nerves. It has been theorized thatlipomas may rarely undergo malignant transformation into a liposarcoma; however, this event has never been convincingly documented. RT POSTERIOR SHOULDER AREA OF PALP SAG20

 

Lipomas typically grow very slow. These adipose tissue lesions tend to increase in size with body weight gain, but interestingly, do not decrease in size with weight loss. Rarely lipomas can grow to an exceptionally large size. Such masses are referred to as giant lipomas. A lipoma is considered giant if it measures at least 10cm in one dimension or weighs at least 1000g.The largest lipoma reported in the English-language literature was removed in 1894 from the left scapula of a 26-year-old male. It weighed an astonishing 22.7kg (which is a little over 50 pounds). The precise etiology of lipoma is unknown. Some studies have demonstrated a genetic link associated with the condition. Lipomas are also associated with certain disorders such as Gardner syndrome, multiple hereditary lipomatosis, adiposis dolorosa, and Madelung disease. Another theory presents the idea that trauma is a possible etiologic factor in lipoma development. According to research, trauma to soft tissue causes rupture of the fibrous septae, which induces adipose tissue migration and proliferation, leading to lipoma formation. Research also links the condition with glucose intolerance, obesity, alcohol abuse, and liver disease

 

ipoma usually presents as a painless palpable mass. It is often diagnosed based on the patient's clinical history and the palpation of a well-demarcated, soft, mobile superficial lesion. When a physical examination is inconclusive, ultrasound is the first-line imaging tool used to evaluate the area of concern. Most lipomas have characteristic sonographic features and do not require additional imaging or biopsy.On ultrasound, lipoma commonly appears as a homogeneous, well-defined, ovoid, echogenic tumor without posterior acoustic enhancement measuring less than 5 cm. In large lipomas, fine linear striations may be seen coursing parallel to the skin. Deep lipomas are often isoechoic or hyperechoic to the adjacent muscle and may also present with posterior acoustic enhancement due to the greater acoustic transmission within fat compared to muscle. On color Doppler mode, lipomas typically exhibit no or minimal internal vascularity. Large size (over 5 cm), heterogeneous echotexture, excessive vascularity, and rapid growth are worrisome features for liposarcoma. As a precaution, lesions presenting with these features are often subjected to further imaging or a biopsy.RT POSTERIOR SHOULDER AREA OF PALP TRVLipoma in the posterior aspect of the right shoulder.22

 

 

 

On computed tomography (CT), the classic appearance of a lipoma is a well-circumscribed, homogeneously low density mass. Lipomas can be easily diagnosed by magnetic resonance imaging (MRI). On all pulse sequences, lipomas present with typical signal intensity similar to the subcutaneous fat. MRI is an excellent imaging tool to assess for atypical features suggesting liposarcoma and demonstrate the surrounding anatomy.Lipomas are benign masses that do not require treatment unless they become symptomatic due to their location or if they compress an organ or impact an organ's function. Some patients may also seek treatment for cosmetic reasons, as larger subcutaneous lipomas may appear esthetically unpleasing. The treatment options typically include steroid injections or surgical excision of the tumor. The latter is considered the most effective method to prevent lipoma from reoccurring. The prognosis for lipomas is very good, and recurrence after surgical removal of the tumor is very low.21-30MRIFatty mass along the posterior aspect of the right shoulder abutting deltoid muscle belly without enhancement represents a lipoma.23