Vulvar leiomyosarcoma

Introduction to vulvar leiomyosarcoma Vulvar leiomyosarcoma is rare, but leiomyosarcoma is the most common in vulvar sarcoma. The disease is a low-grade malignant tumor originating from smooth muscle, which grows fast and mitotic figures are more common. Lymphatic metastasis is rare. basic knowledge The proportion of illness: 0.005% - 0.009% Susceptible people: women Mode of infection: non-infectious Complications: bacterial infection

Causes of vulvar leiomyosarcoma

(1) Causes of the disease

It is mainly from the smooth muscle cells of the vulvar muscle layer or the smooth muscle fibers of the vulvar blood vessel wall, and a few are caused by malignant transformation of vulvar leiomyomas.

(two) pathogenesis

The tumor is an unclear gray-white mass, which is invasively growing, and some may have a pseudo-envelope. The cut surface is gray-red or gray-brown, delicate as a fish-like, often with focal or flaky hemorrhagic necrosis.

Under light microscopy, smooth muscle cell proliferation, cell size, shape, disorder, nuclear, deep staining, nucleoli, nuclear membrane is unclear, visible tumor giant cells, some can be expressed as epithelial or mucinous, The tumor cells of poorly differentiated leiomyosarcoma have obvious atypia, common pathological mitotic figures, tumor cells or pleomorphic tumor cells, or round cells, tumor cells can infiltrate the surrounding muscle layer, blood vessels, etc., but high Differentiated leiomyosarcoma lacks obvious malignant histological features, similar to atypical leiomyomas, so Tavassoli et al (1979) proposed that the diagnosis of vulvar leiomyosarcoma must have: a tumor diameter 5 cm, a mitotic image 5/10 HPF, an invasive margin, Nielsen et al (1996) increased nuclear to severe atypia in these three conditions, and considered that if 3 or more of the 4 conditions were consistent with leiomyosarcoma, if only 2 conditions were met, it was atypical smooth muscle. Tumor, one or none of the normal leiomyomas, Nucci et al (2000) suggest that coagulative necrosis should also be placed in the diagnostic conditions.

Since mitotic figures play an important role in the diagnosis of malignant leiomyomas, it is necessary to make at least 10 to 15 sections from different planes, and count at least 4 to 5 groups of 10 consecutive high power fields at the most active part of the mitotic figures. The highest count group determines the number of split images of the tumor, and at the same time, it is necessary to distinguish the mitotic figures from the nuclear atrophy, folding, strange or deep-stained chromatin.

Electron microscopy shows the medial filaments arranged in a longitudinal direction, dense spots, many swallowing vesicles and a partial or intact basement membrane surrounding each cell.

Masson stained intracytoplasmic myofibrils were red, PTAH stained purple, smooth muscle-specific actin SMA, muscle-specific actin MSA, vimentin were positive, most desmin, estrogen Receptor ER, progesterone receptor PR positive, can also be expressed as calponin (calponinhl), calcium binding protein (hcaldesmin) positive.

It has been reported that tumor recurrence is related to the following factors: tumor > 5 cm; incision in the incision margin; 5 split image / HP in the microscope.

Vulvar leiomyosarcoma prevention

Regular physical examination, early detection, early treatment, and good follow-up.

Vulvar leiomyosarcoma complications Complications bacterial infection

Easy to combine infection and bleeding.

Vulvar leiomyosarcoma symptoms Common symptoms Nodular skin involvement in the shame area Tumor congestion abnormal uterine bleeding vulvar pain

Symptom

At the beginning, the mass is small, located under the skin, without any symptoms, often manifested as slow growth and painless mass, some symptoms are not obvious, because they accidentally touched the tumor and see a doctor, but also no change within a few years, patients often Seek for a lump, bleeding and pain.

2. Signs

Most of the vulvar masses are found in the deep soft tissue around the vestibular gland, the labial ligament, occasionally in the clitoris, pubic lice and perineum. The size of the mass ranges from 2 to 16 cm, usually 5 to 10 cm, round or oval, isolated or multiple Sexual nodular mass, the surface of the tumor in the early stage is intact. As the tumor develops, the skin becomes congested and ulcerated. The advanced tumor may invade the deep tissue and be fixed on the shame, the ischium, or the distant metastasis.

Examination of vulvar leiomyosarcoma

Secretory examination, tumor marker examination, tumor molecular marker P53 tumor suppressor gene detection.

For patients with infiltrated skin or skin ulcers, tissue biopsy can be clamped; for intact skin, needle biopsy or needle biopsy can be performed, or biopsy or biopsy can be performed.

Diagnosis and differentiation of vulvar leiomyosarcoma

diagnosis

Where the subcutaneous lumps of the vulva gradually increase, especially in the short-term, the soft tissue malignant tumor should be suspected. According to the clinical manifestations and histopathological examination and the above characteristics, the sarcoma can be diagnosed.

Differential diagnosis

Clinically often misdiagnosed as vestibular gland cysts, abscesses or other benign tumors, especially young patients, need to pay attention to the following diseases:

1. Atypical vulvar leiomyomas: In addition to the conditions described above, Orii et al. suggested that the mast cell count in the tumor can be used to identify the two, and the number of mast cells in each high power field is <16 as a standard for the diagnosis of leiomyosarcoma. It has a sensitivity of 100% and a specificity of 96%.

2. Postoperative spindle cell nodules: Histologically proliferating spindle cells are similar to malignant smooth muscle cells, and many mitotic figures can reach up to 25/10HPF and marginal infiltration, but the cell atypia is not obvious and there is no pathological mitosis. Like, there is inflammatory cell infiltration, usually occurring weeks to months after vulvar surgery (usually within 3 months), and more importantly, a benign clinical course.

3. Nodular fasciitis: also known as pseudosarcoma fasciitis, a mucin-like mass formed by the proliferation of reactive fibroblasts growing near the subcutaneous tissue of the deep fascia, generally 1.5 to 3.5 cm, very Less than 4cm, characterized by a large number of chronic inflammatory cell infiltration and angiogenesis around the lesion, fibroblasts, collagen fibers and reticular fibers mixed, similar to granulation tissue, sometimes osteoclast-like multinucleated giant cells, no recurrence after resection, And there is a certain degree of self-limiting.

4. Mucinous leiomyosarcoma needs to be differentiated from mucinous degenerative malignant schwannomas, mucinous liposarcoma, mucinous fibrosarcoma, and invasive angiomyxoma.

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