Leiomyosarcoma overview

# Overview
Leiomyosarcoma is a type of sarcoma which is a neoplasm of smooth muscle. (When benign, it is called a leiomyoma.) Most leiomyosarcoma are diagnosed incidentally during hysterectomy of suspected fibroid tumors, it is a very rare cancer, incidence is higher in African-American women and age of diagnosis is usually around after age of 40 years old, it has poor prognosis.  The symptoms of a leiomyosarcoma vary depending upon the exact location, size, and spread of the tumor. A leiomyosarcoma, especially in the early stages, may not be associated with any obvious symptoms. Patients with leiomyosarcoma may present with abnormal vaginal bleeding or growing mass in their abdomen or pelvic. General symptoms associated with cancer may occur including fatigue, fever, weight loss, a general feeling of ill health (malaise), and nausea and vomiting.  The tumors may cause bleeding in the gastrointestinal tract and cause black, tarry, foul-smelling stools (melena), or vomiting of blood (hematemesis) or abdominal discomforts. Surgery is considered the mainstay of treatment for all soft tissue sarcomas, this can be done with hysterectomy and adjuvant chemotherapy or radiation.

# Historical Perspective
Soft tissue sarcoma derived their name from the Greek term for a fleshy lump.  Around 460 B.C, Hippocrates recognized soft tissue tumors in the arm and thigh in older people and recommended the removal by knife as therapy. 
Around 200 C.E., a greek physician named Galen suggested that these lumps were cancerous tumors. 
In 1809, an Edinburg surgeon, Wardrop describes the first illustration of amputation and used the term "soft cancer".
In 1816, Charles Bell, used the term soft tissue sarcoma to differentiate it form carcinoma.
In 1804, Abernethy describes the first classification of the sarcoma.
In 1932, Stout published a litreature on the pathology and treatment of sarcoma.
In 1982, Rosenberg evaluated limb-sparing surgery with adjuvant radiotherapy compared with major amputation.

# Pathophysiology
The pathogenesis of leimyosarcoma is characterized by malignant smooth muscle neoplasm that can appear in any site in the body but most commonly found in the uterus, small intestine and retro peritoneum.

# Causes
Exact cause of leiomyosarcoma is not clearly evident because of rarety of disease nature. It may arise denovo or by genetic instability. Studies revealed that the PI3K/AKT/mTOR, estrogen-mediated S-phase entry and DNA damage response signaling pathways, for which inhibitors have already been developed and approved, frequently harbored genetic changes.

# Differentiating Leiomyosarcoma from other Diseases
Leiomyosarcoma must be differentiated from special subtypes of leiomyoma, othter soft tissue sarcoma, perivascular epitheloid cell neoplasm (PEComa).

# Epidemiology and Demographics
Leiomyosarcoma is one the most common types of soft tissue sarcoma, about 1 person in 100,000 gets diagnosed with LMS each year. Uterine sarcoma are extremely rare, with the incidence of 3 to 7 per 100,000 US population, it is twice more common in African-American women, median age of patients is between 40 to 52 years old.

# Risk Factors:
Clinical data has suggested that the development of leiomyosarcoma is related to radiation exposure. Other risk factors include use of tamoxifen, immunodeficiency, viral infection.

# Natural History, Complications and Prognosis
Leiomyosarcoma most commonly metastasizes to the lungs, abdomen, pelvis, and lymph nodes. Bone and brain metastases are less common sites of involvement. Depending on the extent of the tumor at the time of diagnosis, the prognosis may vary. However, the prognosis is generally regarded as poor. Stage of tumor is the most important prognostic factor.

# Diagnosis
The majority of patients with leiomyosarcoma remain asymptomatic for decades. General symptoms associated with cancer may occur including fatigue, fever, weight loss, and nausea and vomiting. Irregular vaginal bleeding is most common symptom in patients with leiomyosarcoma, other symptoms include feeling pressure in pelvic or abdomen, painless growing mass in abdominal cavity, vaginal discharge.
History and Symptoms | Physical Examination | Laboratory Findings | Chest X Ray | CT | MRI | Ultrasound | Other Imaging Findings | Other Diagnostic Studies

# Treatment
Leiomyosarcoma treatment consist of multidisciplinary approach and is best carried out at the specialized hospital setting. Patients with leiomyosarcoma in early stage of disease can undergo surgery for removal of tumor, this can be done by hysterectomy alone or hysterectomy and chemoradiation. Non surgical treatment options have shown only limited benefit in the treatment of the leiomyosarcoma and are generally considered to be less responsive of chemotherapy and radiotherapy. It has generally noted that only 40% cases responds to the chemotherapeutic regimens. Common drugs used as first line treatment of soft tissue sarcoma include combination of ifosfamide and doxorubicin (Adriamycin).
Medical Therapy | Surgery | Secondary Prevention | Cost-Effectiveness of Therapy | Future or Investigational Therapies

# Case Studies
Case #1

# Related Chapters
Uterine sarcoma