OVERVIEW
Mesenteric liposarcoma mostly occurs in the retroperitoneum and less commonly originates in the mesentery. The tumor tends to grow into a huge mass, irregular in shape, lobulated, clearly demarcated, and encapsulated. The cut surface is grayish-yellow, like lipoma; some are grayish-white or brownish-red, soft and fish-like; some cut surface is moist and jelly-like translucent. It is easy to recur after surgical excision. It is slightly more common in males than females, and the most common age is 40~70 years old.
Etiology
The etiology and pathogenesis of mesenteric liposarcoma have not been clearly defined, and it is currently believed that chemical stimulation, viral infection, trauma, radiation and endocrine factors can lead to the development of the disease. According to the different cell components, liposarcoma can be divided into well-differentiated type, mucinous-like type, round cell type, undifferentiated type and pleomorphic type, among which the first two types have good prognosis.
Symptoms
Abdominal mass is the most common, followed by abdominal and gastrointestinal compression symptoms, such as abdominal pain, abdominal distension, loss of appetite. There may also be low-grade fever, malaise, anemia, and increased white blood cell count. Weight loss can be seen in advanced stage. Tumor invasion of sacral nerve root can cause pain in the lower back and lower limbs, and compression of femoral nerve can cause limitation of lower limb movement. If the tumor is highly malignant, it can metastasize to lung, liver, bone marrow and brain through blood line, with lung metastasis being the most common, and symptoms such as cough and chest tightness are often seen.
Examination
1. Physical examination
Abdominal mass is often palpable and hard.
2 B-mode ultrasound
It can be seen as irregular mass-like shadow, internal hypoechoic, uneven texture, combined with hemorrhage and necrosis, there may be anechoic or weak echogenic area, and there may be peritoneum.
3. Computed tomography (CT) scanning
Soft tissue density shadow can be seen, generally larger, irregular shape, uneven density, may have envelope, uneven enhancement or non-enhancement after enhancement.
Diagnosis
Clinical symptoms are atypical and may include abdominal pain, abdominal distension, loss of appetite, low-grade fever, malaise, anemia, and increased white blood cell count. Abdominal mass is often palpable and hard. Ultrasound and CT examination can clearly locate and diagnose, but the performance varies greatly due to different pathological types and differentiation degrees of liposarcoma, and lacks specificity, which can help early diagnosis. Preoperative diagnosis is difficult, and surgical exploration is often needed to confirm the diagnosis with pathologic examination.
Treatment
Once diagnosed, the disease should be treated with surgery as early as possible. Localized extensive resection is an effective measure to reduce recurrence and metastasis. Since metastasis of liposarcoma through lymphatic system is rare, except for enlarged lymph nodes around the tumor, lymph node dissection is not necessary. Postoperative radiation therapy is supplemented, especially mucinous liposarcoma is more sensitive to radiation therapy. The effect of chemotherapy is uncertain.
Prognosis
The prognosis of well-differentiated and mucinous liposarcoma is good. Other types are prone to recurrence and metastasis, characterized by in situ recurrence and multiple recurrences, and have a poorer prognosis.