Differences between sarcoma and lipoma

Whenever sarcoma-like diseases are mentioned, everyone's faces become extremely ugly, after all, it is a tumor-like disease that is difficult to treat. However, sarcoma diseases also have many classifications, such as myosoma and lipoma. Due to their different growth locations, the harm they cause to the human body and the treatment methods are also different. Let us take a look at the differences between myosoma and lipoma.

( I ) Myoma

Myosoma (fibroma) is also called muscle fibroma. It is often found under the skin, grows slowly, is generally small, has clear edges, a smooth surface, a hard texture, and can be pushed. If mixed with other ingredients, it becomes fibromyoma, fibroadenoma, fibrolipoma, etc. Fibroids, especially desmoids within the abdominal wall muscles, can become malignant and should be completely removed surgically as soon as possible.

Myosoma Introduction

Myofibroma is a collagen-rich fibrous tissue tumor derived from muscle, aponeurosis, and fascia. It is a benign tumor composed of fibrous connective tissue. It is often seen under the skin, grows slowly, is usually small, has clear edges, a smooth surface, a hard texture, and can be pushed. If mixed with other components, it becomes a fibromyoma, fibroadenoma, fibrolipoma, etc. The incidence rate is 1.37% of benign soft tissue tumors. Tumors can occur in large muscles anywhere in the body, most commonly the rectus abdominis muscle of the abdominal wall and the aponeurosis of its adjacent muscles, and are more common during pregnancy and late pregnancy. Those outside the abdominal wall are more common in men, and are prone to occur in the scapula, thigh and buttocks. The age of onset is mostly between 30 and 50 years old, and it is also common in children and adolescents. The cause of this disease is still unclear, but it may be related to trauma, hormones and genetic factors.

Symptoms of sarcoma

The tumor grows slowly and generally does not metastasize much. Other symptoms are very poor. It is often found under the skin, has no adhesion to the skin, and has a certain degree of mobility. It grows slowly and is generally small. The surface of the skin is normal and a smooth, movable, round tumor can be felt under the skin. No tenderness, clear texture, hard. A few have malignant biological behavior, stubbornly relapse multiple times, but rarely metastasize to distant sites. The recurrence rate is 25% to 57%. The recurrence time is usually 1 month to 1 year after surgery, and can even be more than 10 years, so this type of tumor is also called aggressive fibromatosis. Multiple recurrences may cause the disease to spread to a wider range and lead to uncontrollable growth, invading important organs and endangering life.

Myosoma pathology

Microscopically, the tumor contains abundant collagen fibers. The lesion has no capsule and no boundary with the surrounding tissue. Sometimes the surrounding tissue is included in the lesion. Nuclear division is rare, and capillaries and fat cells are relatively rare. A small number of recurrent cases may show morphological changes of fibrosarcoma.

The tumor is located in deep tissue, has no obvious symptoms or only slight discomfort, and grows slowly. The shape is irregular or oval, and its long diameter is consistent with the direction of the affected muscle fibers. The size of the tumor is related to the duration of the disease, and its diameter ranges from a few centimeters to more than ten centimeters. The tumor has unclear boundaries, a smooth surface, no tenderness, and is tough like rubber. It is relatively fixed longitudinally to the invaded muscle, but can move slightly laterally and has no adhesion to the skin. Large tumors can affect movement and compress nerves.

Myosoma treatment and prevention

There are several types of myoma.

a. Xanthofibroma: It is common in the dermis or subcutaneous tissue of the trunk and proximal upper arms. It often arises from small papules after trauma or itching. The lumps are hard with unclear edges. Because of internal bleeding, they contain hemosiderin and are dark brown. If the tumor is larger than 1 cm and grows rapidly, it should be suspected to be a fibrosarcoma and must be completely removed surgically.

b. Dermatofibrosarcoma protuberans: located in the dermis, protruding from the body surface, with smooth surface skin, shaped like keloid, prone to occur on the trunk, low-grade malignancy, with pseudocapsule, prone to recurrence after resection, multiple recurrences increase the malignancy, and can metastasize through the blood. The tumor focus containing enough normal skin and deep adjacent fascia should be removed as soon as possible.

c. Band-like fibroma: It is caused by the reparative hyperplasia of the abdominal wall muscles after trauma or birth injury. It has no obvious capsule and is suitable for surgical removal.

( ii ) Lipoma

Lipoma is a common benign soft tissue tumor composed of mature fat cells and can occur in any fat part of the body. It is more common on the shoulders, back, neck, breasts and abdomen, followed by the proximal extremities (such as upper arms, thighs, and buttocks). It is mainly found under the skin, which is called superficial lipoma. It can also be found deep in the limbs and between the muscle bellies, which is called deep lipoma. The patients are mostly older, mostly middle-aged people between 40 and 60 years old, and less common in children. Deep lipomas often grow along the muscles and can reach deep into the periosteum, but rarely invade adjacent bones. Lipomas rarely become malignant and are easily removed surgically.

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 tumorigenic factors 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.

diagnosis

The diagnosis of this disease is mainly based on clinical manifestations and related examinations. Superficial lipomas can usually be diagnosed through physical examination, while deep lipomas require a combination of imaging and pathological examinations to be diagnosed.

treat