There is a hard lump on the top of my head

The hard bump on the top of the head may be a lipoma. It is a common benign tumor composed of fat cells and can grow anywhere there is fat in the body. The most common areas are shoulders, neck, and abdomen, followed by limbs. It often occurs under the skin, and most people who suffer from the disease are between 40 and 60 years old. It is rarely seen in teenagers. What are the causes and clinical manifestations of lipoma? Let’s take a closer look below.

Causes

The cause of lipoma is not yet fully understood. It may be related to factors such as inflammatory stimulation of connective tissue degeneration, abnormal and disordered adipose tissue metabolism, abnormal secretion of anterior pituitary gonadal hormone levels, congenital dysplasia, and intestinal malnutrition. About 1/3 of patients with multiple lipomas may have a family history.

There is a "lipoma tumorigenic factor" in the human body. Under normal circumstances, this tumorigenic factor is in an inactivated state (inactive state) and will not cause disease under normal circumstances. However, under the influence of various internal and external environmental factors, this lipoma tumorigenic factor is in an active state and has a certain activity. When the body's resistance decreases, the body's lymphocytes, mononuclear macrophages and other immune cells' ability to monitor the tumorigenic factor decreases. Coupled with changes in the body's internal environment, chronic inflammatory stimulation, abnormal systemic fat metabolism and other inducing conditions, the activity of the lipoma tumorigenic factor is further enhanced and combined with certain gene fragments in the body's normal cells to form abnormal gene mutations, causing an abnormal proliferation of normal fat cells and surrounding tissue cells, leading to the deposition of adipose tissue and the formation of lumps protruding from the body surface or various internal organs, namely lipomas.

Clinical manifestations

Superficial lipomas cause few symptoms other than a localized lump. It can be single or multiple, and the size can range from a few millimeters to tens of centimeters. The tumor grows slowly, has a soft texture, clear boundaries, is lobed, has good mobility when pushed, and can cause skin depression when moved. It rarely causes pain, and pain that does occur is often a late symptom caused by large lipomas compressing peripheral nerves.

Deep or subfascial lipomas can cause a variety of symptoms, depending on their location and size. If a lipoma is operated on, it may cause a feeling of stagnation or limitation of movement. Larger mediastinal lipomas may cause dyspnea or palpitations.

Lipomas are common in obese people, and their size increases when weight increases rapidly, but on the contrary, lipomas do not shrink when weight decreases severely.

examine

1. Imaging examination

Depending on the location of the lipoma, ultrasound examination, CT examination, magnetic resonance imaging, etc. can be selected. Ultrasound examination is very helpful for diagnosis. Lipoma appears as a round, translucent mass that can be clearly displayed due to the high density of surrounding tissue. The location, size, texture and blood supply of the mass can be determined. CT showed a mass with characteristics of subcutaneous adipose tissue. In T1-weighted MRI images, it appears as a high signal.

2. Pathological examination

Pathological examination showed that the cut surface was light yellow with a complete thin layer of fibrous capsule and fat lobules separated by trabeculae. The tumor cells are mainly mature adipocytes, with a few lipoblasts occasionally seen. There are generally few blood vessels in the tumor, and focal myxoid degeneration, calcification, or ossification may sometimes be seen.